7.12 Smoking and mental health

Last updated: August 2020     

Suggested citation: Greenhalgh, EM., Jenkins, S, Stillman, S., & Ford, C. 7.12 Smoking and mental health. In Greenhalgh, EM, Scollo, MM and Winstanley, MH [editors]. Tobacco in Australia: Facts and issues. Melbourne: Cancer Council Victoria; 2018. Available from http://www.tobaccoinaustralia.org.au/chapter-7-cessation/7-12-smoking-and-mental-health 

 

In Australia, while the prevalence of smoking is declining in the general community, it remains high among people with mental illness. 1 Compared with the general population, people with mental illness have higher smoking rates, higher levels of nicotine dependence, and a disproportionate health and financial burden from smoking. 2, 3 Smokers with co-occurring mental illness or substance use disorders have limited access to cessation treatment, longer durations of smoking, and lower rates of quitting. Such smokers are also far more likely to die from their smoking than as a result of their psychiatric condition. 2 Australian men with mental illness live 15.9 years less and women live 12 years less than those without mental illness, 4  and most of the excess morbidity and mortality is attributable to smoking-related illnesses such as cardiovascular disease, respiratory disease, and cancer. 4,  5

The mechanisms underlying the relationship between mental health conditions and smoking are complex, and vary between disorders. 6 Smokers often perceive their smoking to be helpful in relieving or managing psychiatric symptoms, such as feelings of depression, anxiety, and stress. 7 Many mental health workers also believe that smoking cessation will exacerbate mental illness. 8 However, recent evidence suggests that the reverse is true; quitting smoking for at least six weeks actually improves mental health, mood, and quality of life, both among the general population and among people with a psychiatric disorder. 7

Smokers with mental illness are as motivated to quit as the general population, and despite lower overall success rates, can quit successfully. 9 Integrating tobacco cessation interventions into routine mental health treatment, and providing more intensive intervention when required, forms an important part of reducing the large health disparities between those with and without a mental health problem. 6, 7

This section includes information on:

7.12.1 Prevalence of smoking among people with mental health problems

Data from the National Drug Strategy Household Survey show that in Australia in 2019 (refer NDSHS 2019 table 2.60), daily smokers were more than twice as likely to have high/very high levels of psychological distress compared with people who had never smoked (25% compared with 12%, respectively) and were more than twice as likely to have been diagnosed or treated for a mental health condition (29% compared with 14%). 10 Conversely, the same 2019 survey shows (NDSHS 2019, table 8.9) that smoking rates among those with mental illness are roughly double those among people without mental illness. Among those who self-reported any sort of mental illness, 20.2% were daily smokers compared to 9.9% of people who did not report mental illness. 10

Smoking prevalence tends to increase alongside the severity of the psychiatric disorder. 8 For example, two Australian studies conducted 10 years apart both found that among people living with psychotic disorders, about 70% of men and 60% of women are smokers. 1,  11 Figure 7.12.1 shows the prevalence of smoking among people diagnosed and/or treated for mental disorders in Australia in 2016.  (Data for 2019 will be added when the 2019 data file becomes available.)

Figure 7.12.1
Prevalence of daily smoking by mental disorder (diagnosed or treated in past 12 months), Australians aged 14+, 2016 
*Estimate has a relative standard error of 25% to 50% and should be used with caution. 

Note: Diagnosed or treatment for the condition are not mutually exclusive. Respondent may have been diagnosed and treated for the condition in the last 12 months.
Source: Australian Institute of Health and Welfare 12

Results from the 2014–15 National Health Survey show a similarly high prevalence of smoking among people with mental disorders, and also show the extremely high prevalence of smoking among those with harmful use or dependence on alcohol or drugs.

Figure 7.12.2
Prevalence of daily smoking by mental disorder (ICD-10 classification), Australians aged 18+, 2014–5

Sources: Australian Bureau of Statistics Table Builder, 13  using data from the National Health Survey 2014–15 14

International data also show high smoking rates among those with mental illness. Large-scale survey research has found that those with any current psychiatric diagnosis had more than three times greater odds of currently smoking than those with no diagnosis, and were much less likely to quit. 15 Among people with anxiety disorders, smoking rates appear to range from 31.5% for people with social phobia to 54.6% for people with generalised anxiety disorder. 16 Smoking rates are also disproportionately high among people with depression, and conversely, smokers have significantly higher rates of lifetime depression. 6 Another study in the US found that adults with serious psychological distress were more likely to be current smokers and to smoke heavily, and less likely to quit than those without serious psychological distress. 17 US studies 18, 19 have estimated that while nicotine-dependent individuals with a comorbid psychiatric disorder make up only 7.1% of the population, they consume more than one-third of all cigarettes.

A 2014 survey of secure mental health services in the UK found that 64% of mental health patients were smokers, compared with 18% of the general population. 20 A meta-analysis of studies from 20 different countries found that people with schizophrenia have more than five times the odds of current smoking than the general population, and smoking cessation rates are much lower in smokers with schizophrenia compared with the general population. 21 Research in the US and Europe has consistently found that the prevalence of smoking is approximately two to three times higher among people with bipolar disorder than in the general population. 6 Limited data suggest that smoking appears highly prevalent among adolescents with diagnoses of mental illness. 22 Both adults and adolescents with ADHD smoke at significantly higher rates than the general population, 5 and the risk of smoking increases with the number of symptoms. 23

An Australian study of people with psychotic illness found that current smokers smoked on average 21 cigarettes per day, 1 compared with an average of 14 cigarettes per day among smokers in the general Australian population  at that time. 24  Among smokers with severe mental illness, other studies indicate average daily consumption of 30 cigarettes, with a range of 5–80 per day. 25,26 Smokers with schizophrenia smoke more heavily and are more nicotine dependent, 27 and extract more nicotine from each cigarette. 28 Evidence suggests that major depression may be a risk factor for progression of nicotine dependence. 29

7.12.2 Smoking prevalence over time among those with mental health problems

In Australia, while the prevalence of smoking is declining in the general community, it remains high among people with mental illness. For example, the prevalence of smoking among Australians with psychotic disorders remained steady at about 67% between 1997 and 2010, while smoking in the mainstream Australian population declined from 26% to 19%. 1 The gap in life expectancy between those with and without mental illness has also widened over time, largely due to smoking-related diseases. 4 Similarly in the US, several studies have shown growing disparities over time between smoking in the general population and among people with high levels of psychological distress and serious mental illness. 30-33  As overall smoking rates decline, those with serious psychological distress comprise a greater proportion of the remaining smokers. 34  These findings suggest that tobacco control policies and cessation interventions that have effectively reduced smoking in the general population have not been as effective for people with severe mental illness.

Nonetheless, there are some encouraging trends. Several US studies have shown increased quit rates over time among people with psychological distress and some mental disorders. 35, 36  Data from the two most recent ABS Health Surveys show that daily smoking prevalence among those with non-psychotic disorders appears to have declined in line with the general population.

Figure 7.12.3
Prevalence of daily smoking by type of condition (ICD-10 classification), Australians aged 18+, 2011–12 and 2014–5

Sources: Australian Bureau of Statistics Table Builder, 13 using data from the Australian Health Survey 2011–1230 and National Health Survey 2014–15 14

7.12.3 Why those with mental health problems are more likely to smoke

There are a number of potential explanations for why people with mental health problems are more likely to smoke; risk factors for smoking among the general population are experienced to a greater degree, and there are also unique factors that contribute to the higher prevalence of smoking. These include:

  • the historical and environmental context: many mental health institutions have a strong smoking culture and have traditionally condoned and encouraged smoking, with cigarettes used by staff to build rapport, calm, reward, or punish clients. 38-41 Mental health staff may also hold negative attitudes toward patients quitting. 42
  • self-medication, such that smoking is perceived to have a beneficial effect on cognition and mood, and to relieve symptoms of mental illness such as anxiety and stress. 43
  • the psychosocial disadvantage of many people living with mental illness, 44 including lower-than-average education levels and income, 38 and high levels of unemployment. 45
  • social inclusion, such that smoking can be perceived as a way to fit in, cope with exclusion, and alleviate stigma among people with severe mental illness. 46
  • a shared genetic predisposition to smoking and mental illness. 43

The self-medication hypothesis suggests that people with mental illness smoke to ease the symptoms of depression, schizophrenia, substance abuse and other disorders, and is the most common explanation for the very high prevalence of smoking among this group. 38,  47 The hypothesis has also been expanded to suggest that smoking can relieve side effects of antipsychotic medication. 41 Smokers with mental illness frequently cite stress and anxiety relief as reasons for smoking, 45 and young people with mental illness perceive nicotine as protective against the adverse effects of stressful stimuli. 22 However, results from recent studies have led to questioning of the self-medication hypothesis 48, 49  (with the exception of ADHD—see Section 7.12.5.3). The supposed beneficial effects of smoking on stress can be largely attributed to the temporary alleviation of nicotine withdrawal symptoms, which creates the false impression that smoking is relaxing. 50 However, smoking actually increases stress levels overall. 8 A 2014 meta-analysis found that quitting for at least six weeks is associated with reduced depression, anxiety, and stress and improved positive mood and quality of life compared with continuing to smoke among people with psychiatric disorders. 7 Smoking is also associated with suicidal ideation, suicide plan, suicide attempt, and suicide death, 51  but this association is reduced when a person quits. 52 Among people with psychosis, one study estimated that smoking contributed to 21% of suicidal behaviours; 53  reducing consumption may also reduce suicidality in this population. 54  A review of smoking among people with schizophrenia concluded that, despite some enhanced performance for cognitive tasks, smoking appears to be less beneficial on schizophrenic symptomology than generally assumed, while clearly increasing the risk of cancer and other smoking-related diseases responsible for early mortality. 48 A 2015 systematic review and meta-analysis also concluded that daily tobacco use is associated with increased risk of psychosis and an earlier age at onset of psychotic illness. The authors propose that smoking could have a causal role in psychosis, which further brings into question the self-medication hypothesis. 55 Smoking may also increase the risk of anxiety and depression. 8

Another proposed explanation for the higher rates of smoking among people with mental health problems is that once addicted, they find it much more difficult to quit than the general population. Although treating tobacco dependence in people with mental illness is challenging, several randomised treatment trials and systematic reviews have documented that success is possible. 56 Smokers with chronic mental illness are able to quit with standard cessation approaches with minimal effects on psychiatric symptoms. 57 (See  Section 7.12.5) Socio-economic status (SES) is inversely related to smoking, such that the prevalence of smoking is substantially higher among lower socio-economic groups (see  Chapter 1.7). Mental disorders are associated with low incomes and higher levels of debt; 58 thus, there is likely interplay between low socioeconomic status, mental illness, and smoking. In 2011–12, 62% of working age Australians with a mental illness were employed, compared to 80% of those without a mental illness. 59 One study found that smokers with mental illness frequently smoke to combat boredom, and suggested that the higher rates of unemployment among this group may contribute to more frequent experiences of boredom and therefore smoking. 45 (See  Section 7.19.2 and Chapter 9,  Section 9.6.4)

Looking at why and how some people resist smoking despite being at-risk can also shed light on potential protective factors. 60 One small study with people diagnosed with mental illness found that strong, negative attitudes to smoking as children that have persisted into adulthood, lasting associations with smoking, a clear sense of ‘self’ separate from peers from an early age, and developing a range of coping strategies and external supports not related to smoking served as protective factors from taking up smoking. 60

7.12.4 Barriers to be overcome when quitting

People with mental health problems face a number of unique barriers to quitting, including misperceptions regarding the safety of stopping smoking, higher levels of nicotine dependence and withdrawal, lower degree of participation in programs, misperceptions of low motivation to quit, socio-economic factors, and systematic barriers to quitting in mental healthcare settings. A systematic review identified smoking for stress management, lack of support from health and other service providers, the high prevalence and acceptability of smoking in vulnerable communities, and the maintenance of mental health as perceived barriers among those with mental illness. 61 An Australian study of smoking behaviours among institutionalised psychiatric populations found systematic barriers to quitting, including cigarettes being the currency by which economic, social and political exchange took place and complex processes of reinforcement to smoke. Escape from the smoking culture of the settings appeared to be extremely difficult for clients and staff. 62

There is a common false belief within mental health settings that quitting smoking interferes with recovery from mental illness, eliminates a coping strategy, and leads to decompensation in mental health functioning. 56 People with mental illness also report similar concerns, which can hinder quit attempts. 63 However, several major reviews have found that quitting does not lead to deterioration in symptoms of schizophrenia, depression, or severe mental illness, 64, 65 and is in fact associated with improvements in mental health among people with psychiatric disorders. 7 Smoking cessation also does not exacerbate anxiety or PTSD symptoms, or lead to psychiatric hospitalisation or increased use of alcohol or illicit drugs. 39, 66 Indeed, smoking cessation interventions during addictions treatment appear to enhance rather than compromise long-term sobriety. 67  Two studies examining whether the treatment of ADHD can enhance response to smoking cessation intervention found no association overall between abstinence and change in ADHD symptoms, 68, 69 and another found that quitting can reduce anxiety and depressed mood in smokers with ADHD. 70 Quitting is also associated with a decreased likelihood of suicide attempt. 52 Lifetime history of major depression does not appear to be an independent risk factor for failure in smoking cessation treatment. 71

Another common misperception is that people with mental illness do not want to quit, which can lead to a lack of encouragement and support to do so. 72 A study of mental health centres found that the most common barrier to staff implementing smoking cessation treatment was a perceived lack of patient interest in quitting. 73 Although the co-presence of mental illness can make quit attempts more challenging 74 and less successful, 75 smokers with mental health disorders are motivated to quit. 9 Studies involving patients recruited from outpatient and inpatient psychiatric settings suggest that they are just as likely as the general population to want to quit smoking. 39 Further, contrary to common beliefs, greater psychiatric symptoms have been shown to predict greater, not lesser, motivation to quit smoking. 76  In British surveys, about half of smokers with mental illness have expressed an interest in quitting when asked. 77 In the US, 20–25% of smokers with mental illness report that they intend to quit smoking in the next 30 days, and another 40% say they intend to do so in the next six months. 56  Another population-level study in the US found that smokers with mental illness were more likely than those without mental illness to attempt quitting, and just as likely to use cessation treatment. 78 Inpatients with mental health disorders appear to be no less motivated to stop smoking than those without mental health disorders and their use of NRT during hospitalisation is similar. 79 One Victorian study of consumers at a psychiatric disability rehabilitation and support service found that while smoking rates were almost four times higher than the general population, there was high interest in quitting and cutting down. 80 US research found that, among a sample of women with PTSD symptomatology and serious mental illness, readiness and intention to quit smoking was high. 81  Smokers with mental illness cite similar reasons for wanting to quit as the general population. For example, one study found that health concerns (73%), cost (71%), advice from a doctor (54%), and advice from others (64%) prompted a desire to quit, while social support from family and friends (58%), direction from a doctor (46%), use of NRT (31%), and the advice of friend who had quit (23%) were factors that enabled quitting. 82

7.12.5 Interventions for reducing smoking for those with a mental health problem

Smoking has a disproportionate impact on the mental and physical health of people with mental illness, therefore treating nicotine dependence should be a high priority and form part of routine care. 8 However, progress in the development of cessation treatments for people with mental health problems has traditionally been slow, in part because smokers with a current mental disorder have been excluded from most smoking cessation trials. 83 Given the growing body of evidence showing that quitting is typically not detrimental to psychiatric symptoms and, in fact, may lead to improvements in mental health and wellbeing, 7,  84 cessation should be encouraged and supported among smokers with comorbid mental disorders as it is among smokers in the general population. 6 However, as with any other stressor, the stress of cessation could temporarily affect symptoms; 39 therefore, monitoring of patients’ psychiatric status during the quitting process is warranted. 6 Nonetheless, people with a mental illness should be offered the same smoking cessation interventions that have been shown to be effective in the general population, 85 with optimal treatment comprising behavioural and pharmacotherapy interventions, alone or in combination. 86 Smokers with chronic mental illness can successfully quit with standard cessation approaches, and longer maintenance on pharmacotherapy can reduce the typically high rates of relapse without detrimental effects on psychiatric symptoms. 57

An important consideration in treating nicotine dependence is the impact of smoking on psychiatric treatment. Smoking complicates the treatment and course of psychiatric disorders through its profound effect on the metabolism of pharmacotherapies, and is therefore one of the factors that leads to individual differences in drug responses. 6 For example, smoking can interfere with the medications taken for schizophrenia and depression, therefore the doses of some psychotropic medications may need to be decreased following cessation. 85, 87   Patients with mental illness can be offered the same cessation medications as the general population, 88  but should be monitored closely. The typically higher levels of nicotine dependence among smokers with mental illness mean that larger doses of NRT, combination pharmacotherapy, and a longer duration of therapy may be necessary. 8  Australian research found that cessation support after discharge from an inpatient psychiatric facility was effective in encouraging quit attempts and reducing cigarette consumption up to 6 months post-discharge. 89

SANE Victoria and Quit SA, in collaboration with the Tobacco and Mental Illness project in South Australia, have each developed resources to help long-term psychiatric clients to quit, and resources for carers and mental health workers to use as well as a group program for smoking cessation. 90,91  Similar programs have been run in other states. 92 All state and territory Quitline services adhere to protocols for tailoring assistance to callers with mental illness. As well as training Quitline counsellors in the special issues for people with mental illness, they co-ordinate intervention with the person’s healthcare professionals. 93

7.12.5.1 Depression

Compared to people without depression, people with depression are about twice as likely to be smokers, and are less likely to succeed in quit attempts. 94, 95   They are also more nicotine dependent, more likely to suffer from negative mood changes after nicotine withdrawal, more likely to relapse, and experience disproportionate morbidity and mortality from smoking-related disease. 94 Depression is also related to psychosocial characteristics that make it more difficult to stop smoking, for example, lower self-esteem and self-efficacy for quitting, and greater likelihood of unemployment, poorer social support networks and poorer physical health. 96 Recent findings from the Four Country (Canada, US, UK, and Australia) International Tobacco Control Study showed that smokers with depressive symptoms or diagnosis make more quit attempts than people without depression, but they were also more likely to relapse in the first month. 97 Despite this, meta-analyses suggest that a lifetime history of major depressive disorder, in itself, does not predict failure to quit smoking. 71  A 2015 review of depression and smoking concluded that: depressed smokers are motivated to quit; smoking cessation does not exacerbate symptoms of depression; depression does not have a negative impact on smoking cessation outcomes; and the self-medication hypothesis does not account for tobacco dependence and depression co-morbidity. 98 Indeed, a growing body of evidence supports the beneficial role of quitting in reducing depression. 7,  99

A meta-analysis of treatment trials in smokers with depression published in 2010 concluded that NRT was more effective than placebo, and that adding behavioural mood management to cessation counselling improved treatment outcomes. Notably, only three trials included smokers with current depression, therefore the findings were most relevant to smokers with a history of depression. 100  A 2013 Cochrane review evaluated the effectiveness of smoking cessation interventions in smokers with current or past depression. It concluded that adding a psychosocial mood management component to a standard smoking cessation intervention increases long-term cessation rates in smokers with both current and past depression when compared with the standard intervention alone. Bupropion was beneficial for smokers with a history of depression, but there was a lack of evidence regarding its use with smokers with current depression. There was not enough evidence regarding the effectiveness of other antidepressants for quitting in current or past depression, nor for the effectiveness of standard smoking treatments that do not target depression, such as nicotine replacement therapy and psychosocial smoking cessation interventions. 94  A placebo controlled trial published in 2013 examined the effects of varenicline on smoking in people with stable current or past major depression. Findings showed that varenicline significantly increased continuous abstinence during the last month of treatment and up to a year, without exacerbating depression or anxiety; therefore, it appears to be a well-tolerated and effective treatment for smoking cessation in people with depression. 101  A 2017 systematic review and meta-analysis concluded that smoking cessation interventions, particularly pharmacological treatments, appear to increase short-term and long-term smoking abstinence in individuals with current depression, although noted that the evidence is weak. 99

  7.12.5.2 Anxiety

Despite the high rates of smoking among those with anxiety disorders, there is a dearth of evidence regarding effective cessation interventions for this population. 6 A randomised controlled trial published in 2011 found that anxiety diagnoses were common among treatment-seeking smokers and were related to increased motivation to smoke, elevated withdrawal, lack of response to pharmacotherapy, and impaired ability to quit smoking. 102 Another study found that smokers with social anxiety disorder experienced higher levels of craving and urge to smoke during quit attempts, which could explain their worse cessation outcomes. Such smokers would likely benefit from additional treatment aimed at managing or reducing their social anxiety symptoms, and NRT also seemed to help alleviate the relationship between social anxiety and cravings. 103 Overall, further research is needed on how best to support quitting among people with anxiety disorders. 6

7.12.5.3 Attention-deficit/hyperactivity disorder (ADHD)

ADHD is one of the most common psychiatric disorders, and is associated with a wide range of impairments and risks into adulthood. 104 Smoking is one such risk, with young people with ADHD beginning smoking earlier, and being two to three times more likely to smoke, compared to those without ADHD. The substantially higher prevalence of smoking persists into adulthood, and adults with ADHD are also less likely to be successful at quitting. 105-107

There is a growing body of evidence that stimulant medication, which is a front-line treatment of ADHD, may influence smoking-related outcomes. 105 Nicotine and stimulant medications operate on the same pathways in the brain, and both appear to help alleviate some of the symptoms of ADHD, which may help explain the very high rates of smoking among this group. 108   ADHD medication (i.e., stimulant treatment) reduces smoking rates and smoking withdrawal, therefore early and consistent stimulant treatment of ADHD may reduce smoking risk. 105, 109  Bupropion, NRT, and possibly varenicline—approved smoking cessation medications—have also shown efficacy in treating symptoms of ADHD; 109, 110   however, further research is needed to examine its effectiveness in treating comorbid ADHD-smoking. 6 Non-pharmacological interventions, particularly cognitive-behavioural therapy, also show promise for the treatment of ADHD, and warrant further investigation for supporting cessation among this population. 6 Limited evidence also suggests that financial incentives may be a useful approach for promoting short-term cessation in adult smokers with ADHD. 111

7.12.5.4 Substance use disorders

Smoking prevalence among people with substance use disorders is substantially higher than the general population, 36, 112, 113  and many people who successfully overcome their substance use disorder will go on to die from a smoking-related disease. 114  People with substance or alcohol use disorders have: greater lifetime and current smoking, nicotine dependence, and non-cigarette tobacco use; lower quitting; and differences in quit attempts and withdrawal symptoms compared with people without such disorders. 115 Many health risks for dual use of alcohol and tobacco are multiplicative rather than simply additive. For example, the risk of oesophageal cancer is greater among heavy alcohol users as a result of alcohol allowing tobacco toxins to penetrate more deeply to basal layers. 116  Similarly, there is evidence that smoking cannabis is a risk factor for many of the same illnesses as tobacco. 117-119  Cannabis poses unique problems for users since it is often mixed with tobacco, potentially inducing double dependence. In 2016, 32% of smokers in Australia reported recent use of cannabis, compared to 7% of non-smokers.(see Chapter 1,  Section 1.10) Most people who seek treatment for substance use disorders smoke tobacco as well. 120  Smoking rates among people in addiction treatment are more than double those of people with similar demographic characteristics. 113  Australian research in the early 2000s found that smoking prevalence in this population ranged from 68–98% 121, 122  and the 2014–15 National Health Survey also showed extremely high prevalence of smoking among those with harmful use or dependence on alcohol or drugs (see Section 7.12.1). One US review highlights consistently extremely high smoking rates and subsequent comorbid health risk among people with alcohol and drug use disorders, with rates being greatest among those enrolled in methadone maintenance and in-patient addiction treatment. 123

Treatment centres for substance use disorders have traditionally not prioritised treating nicotine addiction due to lack of staff training, lack of integration into usual care, and because of the common misperception that quitting may be detrimental to the treatment of alcohol or other drug use. 124, 126  Substance abuse counsellors often have limited knowledge of the smoking cessation medications available for those trying to quit 127  and their implementation of tobacco cessation guidelines is inconsistent. 128  A study of staff and management attitudes and practices in Australia found smoking received little systematic attention, with concerns about possible negative impact on other treatments, absence of policy, and lack of training being major impediments. 129  Research in the US found that smokers with a substance use disorder who had undergone addiction treatment were less likely to quit smoking than those who had never received such treatment, possibly due to false beliefs about smoking as a coping strategy and staff attitudes that may discourage cessation. 130  Some centres may even endorse occasional smoking by staff with clients 131  or rely on cigarettes to stabilise mood in their patients. 39, 132

Contrary to staff perceptions, smokers with substance use disorders are motivated to quit. 133 However, despite this motivation to quit, there appears to be a wide variation in readiness to seek help to do so, 39, 67, 132, 134  which may be due to a lack of confidence in or wariness of quitting multiple substances at once. 134  Research in the US showed that when provided with a tobacco free treatment environment, patients with substance abuse and mental illness can and do make the decision to quit tobacco and maintain their abstinence, which in turn helps them to remain sober. 135  While negative affect can hinder quit attempts, patients in an addictions treatment setting can successfully quit smoking regardless of current depressive symptoms. 136 In the US, despite being lower than for people without the disorders, the smoking quit rates for people with alcohol use disorders has increased over time. 36

Perhaps most importantly, smoking interventions and cessation during substance use treatment appear to enhance rather than compromise long-term abstinence from other addictive drugs. 9, 137, 139  Including cessation interventions in the course of addiction treatment can increase quit attempts among smokers. 140, 141  A 2015 systematic review of smoking cessation interventions for adults in substance abuse treatment or recovery concluded that NRT, behavioural support, and combination approaches appear to increase smoking abstinence in those treated for substance use disorders. However, the authors note that higher quality studies are needed to strengthen the evidence base. 142  Some research indicates that drug treatment clients can successfully quit smoking at rates similar to the general population when given access to an intensive intervention. 143  Several studies suggest that varenicline may promote smoking changes and concurrently help reduce heavy drinking in people with alcohol use disorders. 144-146 However, use of bupropion by abstinent alcoholic smokers does not appear to increase long-term smoking cessation. 147 For methadone maintenance patients, varenicline 148 and NRT 149  may be effective for promoting tobacco abstinence. 

Several studies have explored the role of contingency management (i.e., financial incentives) in promoting abstinence. One study found that contingency management was associated with more short-term abstinence and lowered nicotine addiction among current and former injecting drug users. 150  Another study found that contingent vouchers had limited effects on long-term smoking abstinence among smokers in residential drug treatment, but the effects were improved when vouchers were combined with motivational interviewing. 151  A randomised trial similarly found that adding contingency management to an evidence-based smoking cessation treatment that included medication and behavioural counselling doubled the quit rate at the end of treatment among smokers with alcohol abuse or dependence. 152  Contingency management may also promote smoking reduction in more severe substance abusers, such as those in residential services and opioid-maintained patients. 153-155  Such interventions appear to increase abstinence self-efficacy among residential substance abuse treatment patients. 156  Increasing tolerance for withdrawal and abstinence discomfort, addressing expectations, and increasing motivation may also be important when implementing incentive programs. 157  Other strategies include brief advice plus NRT, which appears to be a cost-effective way to reduce smoking for smokers in residential alcohol treatment. 158  A small study found that methadone users responded positively to a computer-based education program highlighting the hazards of smoking. 159

As with mental health and correction services, public health experts have identified a need for policy and training initiatives to address past neglect of tobacco-control issues. 160, 161 Systematic intervention around the 5As framework, tailored to the needs of client groups, would provide a good foundation for this work. Factors promoting smoking cessation programs within substance abuse clinics include supportive systems and integration within other treatments, educating providers about the beneficial effects of cessation for their clients, staff training, and encouraging and assisting staff to quit. 132  One study found that an intervention based on organisational change helped to shift the treatment system culture and increase tobacco services in a residential addiction treatment setting. 161

Future clinical research in this area and its translation into practice may be improved by recruiting and retaining a broader range of people with drug dependencies, particularly those who are not currently being reached through mainstream interventions, and by longer-term follow-up. 162  Research as to the role of social bonding around tobacco use and its normalisation in drug treatment settings may be useful in guiding future practice. 134

7.12.5.5 Post-traumatic stress disorder (PTSD)

The prevalence of current smoking in individuals with PTSD is substantially greater than that for the general population, and is estimated to be about 45%. A systematic review concluded that there appears to be a causal relationship between PTSD and smoking that may be bidirectional. PTSD, rather than trauma exposure itself, appears to have a greater influence on a person’s risk of smoking, and specific PTSD symptoms may contribute to smoking and disrupt cessation attempts. 163  Evidence suggests that people with PTSD smoke to cope with negative affect and anxiety, 57  and PTSD is associated with higher levels of consumption (i.e., more cigarettes smoked per day). 164  Despite the higher smoking and lower quit rates, there is relatively little research on effective cessation interventions for this population. 163

To date, there have only been a very small number of randomized clinical trials examining smoking cessation interventions in smokers with PTSD. 57  Two studies focused on integrating cessation treatment into ongoing mental healthcare, and both found that the integrated care group achieved significantly higher long-term abstinence. 165, 166  Such integration also appears to be cost-effective. 167  A pilot study with 15 veterans found that bupropion was well-tolerated and effective in helping the participants to quit, with 40% maintaining abstinence. 168  Another small study (N=22) examined the effects of combining contingency management (i.e., monetary rewards) with counselling sessions, NRT, and bupropion. Abstinence rates were higher among the group that received rewards, however the difference was non-significant. This may have been due to the very small sample size, therefore larger studies may help determine the effectiveness of this intervention. 169  A larger randomised controlled trial concluded that integrating motivational interviewing into a PTSD home telehealth care management program is an effective method to help veterans with PTSD quit smoking. 170  A number of case studies suggest that combining cognitive processing therapy with evidence-based smoking cessation interventions may improve both cessation outcomes and PTSD symptoms. 171

7.12.5.6 Bipolar disorder

People with bipolar disorder are about three and a half times more likely to smoke than the general population, and have much lower quit rates than smokers without a comorbid condition. 172, 173  In addition to contributing to increased morbidity and mortality, smoking has also been implicated in the progression of bipolar disorder. 174  However, despite these high rates of comorbidity and related morbidity, there is only a modest field of research focusing on smoking among individuals with bipolar disorder. 175  To date, there have only been a small number of clinical studies on cessation interventions among smokers with bipolar disorder. Researchers have highlighted challenges in recruitment and low eligibility rates as significant hurdles to such studies, and have noted that many health professionals remain wary of encouraging cessation among people with bipolar disorder. 173  Nonetheless, recent research has attempted to address this gap.

Two very small studies found that buproprion 176  and varenicline 177  were well-tolerated and led to reduced smoking. Subsequent larger studies have also supported the effectiveness of varenicline. The largest study included 247 smokers with schizophrenia or bipolar disorder. Participants received 12-week treatment with both varenicline and cognitive behavioural therapy, and those who had 2 weeks or more of continuous abstinence at week 12 (n=61) were randomly assigned to receive cognitive behavioural therapy and varenicline or placebo from weeks 12 to 52. After a year, those treated with varenicline were more than six times more likely to be abstinent (60%) than those treated with placebo (19%). Importantly, there were no impacts on psychiatric symptoms. 178  Another randomised controlled trial of varenicline included 60 smokers with bipolar disorder. At 3 months (end of treatment), significantly more participants quit smoking with varenicline (48.4%) than with placebo (10.3%). At 6 months, about 19% of those treated with varenicline remained abstinent compared to about 7% assigned to placebo. Psychopathology scores remained stable, although varenicline-treated participants reported significantly more abnormal dreams. The authors call for medication trials of longer duration, and vigilance for neuropsychiatric adverse events. 179

7.12.5.7 Schizophrenia

Schizophrenia is a chronic and severe mental illness that affects about one in 100 people. 180  People with schizophrenia are more than five times more likely to smoke than the general population, 21 and tobacco-related conditions are responsible for about half of total deaths in people with schizophrenia. 181  Rates of cessation for smokers with schizophrenia are half those for the general population, partly because of their lower motivation to quit, fewer cessation attempts, increased level of nicotine dependence, and reduced access to treatments. 182  They may also perceive themselves to be at lower risk of smoking related-disease. 183  Healthcare services have traditionally condoned or encouraged smoking and failed to offer tobacco cessation interventions to patients with schizophrenia, mainly due to beliefs about the benefits of smoking to symptoms, stigma, lack of information, or perceived hopelessness regarding abstinence. 184, 185  However, in recent times there has been considerable interest in developing effective smoking treatment for this population, 6 and guidelines have been published that include cessation interventions for smokers with schizophrenia. 85  Smokers with a psychotic disorder are capable of long-term reduction and abstinence with appropriate intervention and support. 186  Once people with schizophrenia have successfully quit, the use of antipsychotics may need to be reviewed, as tobacco smoke can differentially affect drug metabolism and the effects of antipsychotic medications. 8,  187

A 2013 Cochrane review of interventions for smoking cessation and reduction in individuals with schizophrenia concluded that bupropion increases smoking abstinence rates in smokers, without any deterioration of mental state. Varenicline may also improve smoking cessation rates, but the authors noted a possibility of adverse psychiatric effects, such as increased suicidality. There is some evidence that contingent reinforcement (i.e., monetary rewards) may help people with schizophrenia to quit and reduce smoking in the short term. 185 Building on the Cochrane review, a 2015 systematic review and meta-analysis examined the evidence regarding varenicline for smoking cessation in people with schizophrenia. It concluded that while there did not appear to be any adverse psychiatric outcomes, varenicline was not found to be superior to placebo for quitting. 188  Another 2015 review of smoking cessation in people with schizophrenia concluded that the most promising evidence is for bupropion, and that pharmacological interventions do not appear to increase adverse events. It suggested that the lack of evidence for NRT and varenicline may be due to the paucity of research. Behavioural and psychosocial interventions are also promising, particularly when combined with pharmacotherapy. The authors highlight the importance of carefully monitoring antipsychotic levels, and suggest that encouraging physical activity may help to negate potential weight gain and diabetes risk following cessation. 189  A further review of the evidence recommended that people with schizophrenia should receive varenicline or bupropion with or without nicotine replacement therapy in combination with behavioural treatment. Maintenance pharmacotherapy for 1 year appears to improve sustained abstinence rates. 190

Results from a large randomised controlled trial were published in 2016, which found that varenicline was more effective than bupropion and nicotine patch in smokers both with and without psychiatric disorders (including schizophrenia), whereas bupropion and nicotine patch were similarly effective, and both more so than placebo. The authors also examined the safety of the medications, and concluded that they can be used safely by psychiatrically stable smokers; there was no increase in neuropsychiatric adverse events attributable to varenicline or bupropion relative to nicotine patch or placebo. 88  In September 2016, the FDA released a preliminary review of this trial, suggesting a number of problems with the study. The review supported similar conclusions about the relative rates of events: in patients without prior psychiatric history, events did not seem to be more frequent in varenicline, bupropion, or NRT-treated patients than in placebo-treated patients. The review also found that among patients attempting to quit, events were more common in those with psychiatric history than those without, regardless of which treatment they received. Of concern however, was a possible increased risk of neuropsychiatric events in patients with psychiatric history in the varenicline or bupropion group compared to placebo. This trended toward statistical significance, but was not observed in NRT-treated patients. 191

Additional recent randomised controlled trials 192, 193  and a systematic review and meta-analysis 194  have supported the safety and efficacy of varenicline for reducing smoking in people with schizophrenia. A 2017 review recommends that smokers with schizophrenia should receive varenicline, bupropion with or without NRT, or NRT, all in combination with behavioural treatment for at least 12 weeks. Maintenance pharmacotherapy may reduce relapse and improve sustained abstinence rates. It notes that controlled trials in smokers with schizophrenia consistently show no greater rate of neuropsychiatric adverse events with pharmacotherapies than with placebo. 195

7.12.6 Role of health professionals and health settings

Medical and mental health professionals often overlook the importance of addressing tobacco use with their patients. 38, 196 Smoking is often not asked about or recorded as a standard part of psychiatric assessment, and even when it is, inclusion of smoking cessation in treatment planning is often inconsistent. 38, 197-199 This may be partly due to the erroneous beliefs held by some mental health workers that smoking is one of the few pleasures clients have, that smoking reduces stress and anxiety, 44, 200  that those with mental illness are not motivated to quit, 72  or that there are more pressing concerns for patients with acute psychiatric symptoms. 56

International evidence suggests that cessation support for inpatient smokers by staff is likely to be severely compromised by low levels of knowledge and awareness of tobacco dependence. 201  Several Australian surveys have found strong support for the provision of smoking cessation treatment among mental health service staff; 202, 203 however staff report significant barriers to providing such care. 202 Commonly cited barriers include inadequate resources, cultural norms, client resistance, and lack of training and confidence. 204-206   More experienced staff, and those with tobacco cessation training, are more likely to help their clients quit smoking. 207,  199,   208

Healthcare professionals, including physicians, psychiatrists, and psychologists, have an important role in the recognition and treatment of tobacco use disorders in patients with psychiatric illnesses, and providing cessation treatment for all patients with a co-occurring tobacco use disorder should form part of routine care. 8,  209, 210  A 2015 systematic review and meta-analysis concluded that while there has been progress, offering smoking cessation advice should receive a higher priority in everyday clinical practice for patients with a mental health diagnosis. 211  Encouraging longitudinal research in the US found that smokers who had seen mental health professionals for mental health problems had higher odds of having made attempts to quit in the past year, and were more likely to have used cessation assistance. 212  However, another longitudinal US study looking only at psychiatrists found that they are screening for tobacco use at declining rates, and the proportion of smokers provided with treatment remains low. 213

As in the general population, people with mental illness should be given advice and support to quit using the 5As framework. 214  Given that people with mental illness are often highly nicotine dependent, and are more likely to socialise with smokers, more intensive interventions may have greater success. This might involve NRT or other pharmacotherapies, as well as referral to a specialised individual program, such as the Quitline, or a group program. The integration of cessation treatment into existing care by health professionals results in greater engagement, greater use of cessation pharmacotherapy, and increased likelihood of abstinence. 165  Quit Victoria has suggested a number of strategies that mental health services could implement to reduce smoking-related harms, including:

  • routinely asking clients about their smoking and recording responses
  • referring clients and staff to Quitline, a doctor, or a local quit smoking program
  • establishing or reviewing smokefree policy
  • encouraging staff to complete further training in smoking cessation
  • displaying posters and print resources
  • referring staff and clients to the Quit website for information on services and smoking care medications. 215

An important part of providing smoking cessation support for those with mental health disorders is for mental health services to develop comprehensive policy on smokefree environments, documenting tobacco use, and continuing support on discharge. This requires leadership from management, staff training, and consistency across services. 216,  217  An audit of an Australian psychiatric hospital found that the setting did not conform to current clinical practice guidelines as it often failed to document smoking status, despite nicotine dependence being the most commonly diagnosed psychiatric disorder. 218  Another Australian study of public psychiatric inpatient units found that over one-third of inpatients started smoking during their admission, and that staff often provided cigarettes to patients. Only half of respondents reported that all patients were assessed for smoking status. The study suggests that failure of psychiatric services to provide smoking care is systematic and not related to particular types of services. 219

Some psychiatric services have become smokefree 220  and there is evidence that hospitalisation in a smokefree environment is associated with increases in patients’ expectancies about quitting and staying a non-smoker, 221  and with reduction in cigarette consumption. 222  A systematic review concluded that smokefree psychiatric hospitalisation may have a positive impact on patients' smoking-related behaviours, motivation, and beliefs, both during admission and up to 3 months post discharge. 223  During smokefree psychiatric hospitalisations, offering patients NRT directly on admission, educating patients on the benefits of NRT, and increasing the dosage for more dependent smokers can help with managing nicotine withdrawal. 224  Community support post-discharge may also help smokers to maintain abstinence. 225  Psychiatric hospitals in the US that voluntarily adopted such bans have documented little-to-no disturbance in patients’ behaviour and time savings for staff members. 56  A study in France found that staff members of a psychiatric facility were exposed to substantially lower levels of secondhand smoke post-ban. 226  However, an Australian study published in 2015 found that adherence to smokefree policy in an inpatient psychiatric facility was poor, with more than four in five smokers still smoking, and only about half perceiving staff to be supportive of the policy. 227  Two Australian studies have found that about only about half of psychiatric patients feel positively about bans, 227, 228  while another found that only about one quarter of mental health staff agreed with a total smoking ban. 229  Some patients also perceive the restrictions to be a form of punishment. 230  There have been debates recently regarding the ethics of implementing complete smoking bans in psychiatric hospitals; proponents argue that the ‘smoking culture’ creates disproportionate harm among people with mental illness, while opponents argue that it is unethical to deprive patients of autonomy and impose treatment. 231, 232

Together, evidence suggests that there is a critical need to engage healthcare providers, policy-makers, and mental health advocates in the effort to increase access to:

  • evidence-based tobacco treatment for smokers with mental health disorders
  • smokefree environments for mental health treatment
  • training for clinicians in cessation treatment
  • systems for routinely identifying patients who smoke, advising cessation and providing treatment or referral. 56

Relevant news and research

For recent news items and research on this topic, click  here. ( Last updated March 2021)

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