Gender differences and risk factors for smoking among patients with various psychiatric disorders in Saudi Arabia: a cross-sectional study

Smoking is a global health risk with a well-established serious morbidity and mortality profile. In 2015, the World Health Organization (WHO) estimated that more than 1 billion people smoke tobacco worldwide, resulting in approximately 6 million deaths per year [1]. In Saudi Arabia, the average prevalence of current tobacco smoking among adults was estimated at 22.6%, with a wide range (11.6–52.3%) reported by studies targeting diverse populations [2]. Interestingly, there is a striking difference in the smoking rates between males (26%) and females (3–9%) in Saudi Arabia [2, 3]. This may partially explain the higher smoking rates found in several studies that included only males, for example, 35% in a military population [4] and 34–52% among male patients at primary care centers [5, 6].

Systematic reviews and other types of reviews have found a positive association between smoking and psychiatric disorders [7, 8], especially among females and in younger population [9]. For example, the prevalence of smoking has been reported to be two- to threefold higher among psychiatric patients than in the general population [10‐13]. In addition, smokers have been found to have two- to threefold higher risk of developing psychiatric illness and substance use disorders later in life [14]. Moreover, smoking by psychiatric patients is associated with greater disability and poorer quality of life [15]. The impact of smoking on mortality among psychiatric patients is believed to be even greater than that in the general population, probably because of the excess mortality from cardiovascular diseases, stroke, and respiratory cancers among these patients [16]. The impact on mortality is complicated by the effects of smoking on some psychiatric symptoms, which makes cessation more challenging in these patients [17].

Although a higher smoking prevalence among psychiatric patients is well established, the overall impact is probably affected by several patient factors, including sociodemographic profile, type, and number of psychiatric disorders, pharmacological therapies, and concomitant substance abuse [8, 18‐21]. The complex interplay of these factors in different populations complicates comparisons between studies. The objective of the current study was to estimate the prevalence of current smoking in a mixed psychiatric population in Saudi Arabia and examine the effect of the above factors on smoking rates. Suitable data from Saudi Arabia are very limited and outdated, and they lack adjustment for several confounders [22]. In addition, the impact of gender, which has received little attention in Western research, cannot be ignored in our population because of the substantial gender-specific difference in smoking prevalence. Therefore, we examined gender-specific associations between smoking and psychiatric disorders.

We found a high prevalence of current smoking in a large sample of psychiatric outpatients and inpatients in Saudi Arabia. As in the general Saudi population—although at a higher rate—smoking prevalence was much higher among males than females (58% versus 7%). This was almost double the rate of current smoking recently reported by the WHO for the general Saudi population (26% in males and 3% in females) [3]. However, the prevalence we found was almost identical to the current smoking rates (58%) reported among 505 male outpatients recruited from five hospitals in Saudi Arabia in 1996 and 1997 [22]. Unfortunately, females were not included in the previous study, which reported the only published data regarding smoking by psychiatric patients in Saudi Arabia [22]. Several hypotheses have been suggested to explain the higher smoking rates among psychiatric patients [8, 26]. The most widely accepted hypothesis is self-medication; that is, patients smoke to reduce the impact of specific psychiatric disorders and medications [8, 17, 20, 26]. Other hypotheses include shared genetic factors that control the susceptibility for both smoking and psychiatric disorders and shared environmental factors, such as stress, that can increase the incidence of both smoking and psychiatric illness [8, 26].

Higher rates of current smoking among male psychiatric patients is consistent with the findings of nearly all Western and Eastern studies [20, 27‐32]. For example, male versus female rates have been reported as 66% versus 56% in the US [32], 69% versus 48% in France [20], 32% versus 21% in Japan [29], 59% versus 41% in Brazil [28], and 78.4% versus 36.2% in Iran [30]. However, a very large male–female difference, as found in the current study, has been reported in only a few Eastern countries, such as India (53% versus 9%) [31] and Bahrain (47% versus 4%) [27]. This reflects the variability in gender-specific rates of current smoking in the general population of Western and Eastern countries [33]. Smoking among females in a conservative society such as Saudi Arabia could be perceived as impairing the feminine Islamic image of women [2, 34]. Another explanation is that it is more inconvenient for females to obtain cigarettes and find a place to smoke [34]. However, we cannot exclude the possibility that current smoking by female patients is under-reported as a consequence of its social stigma [2]. Interestingly, the persistence of a marked gender difference in smoking rates among our patients, after stratifying by psychiatric disorder and psychotropic medication, might indicate that the gender effect is independent of the psychiatric impact. In addition, the persistence of sociodemographic risk factors for smoking (such as low education, low income, and being unmarried) in a multivariate analysis, especially in men, is more evidence that the motivations for smoking in the general population [4, 35] are the same as those in psychiatric patients [5, 36, 37]. The disappearance/attenuation of sociodemographic risk factors for smoking in multivariate analysis among females could be related to the low prevalence of smoking among this group rather than real lack of associations.

As found in previous studies, smoking rates in the current study were highest among patients with substance abuse disorder [26, 29]. In addition, current smoking and substance abuse were strongly and independently associated, even after adjusting for psychiatric disorder or psychotropic medication [36, 37]. This may further explain the high smoking prevalence among those with secondary psychiatric disorders in the current and previous studies [20, 22, 28]. A large twin study showed that shared genetic and, to a lesser extent, environmental risk factors predispose individuals to lifetime comorbidity of common psychiatric and substance abuse disorders [38].

Although attenuated in multivariate analyses, smoking in the current study was strongly associated with primary psychotic disorders and/or use of antipsychotic medications. High smoking rates among patients with schizophrenia/schizoaffective disorders have been consistently reported in previous studies: 66–74% in previous studies [12, 18, 20, 22, 32, 36] compared to 64% in the current study. Higher smoking rates were also reported among patients using antipsychotic medications [20]. It has been suggested that smoking reduces the intensity of some psychiatric symptoms and improves cognitive and concentration functions in patients with schizophrenia [8, 39, 40]. However, smoking is also associated with an increased risk of psychosis and an earlier age at onset of psychotic illness [41]. In addition, smoking was reported to reduce the side effects of antipsychotic medications, especially extrapyramidal manifestations [40, 42]. Yet, smoking can have effects on the metabolism of antipsychotic medications, especially clozapine and olanzapine, such as decreasing their blood levels and increasing the clinically effective dose [43]. Therefore, it has been suggested that doses of clozapine and olanzapine be increased by 50 and 30%, respectively, for smokers to attain an equivalent clozapine or olanzapine blood concentration [44]. The complex association between smoking and schizophrenia, as well as antipsychotic medications, can make smoking cessation challenging and cause sudden withdrawal symptoms [17, 43]. Interestingly, the lower smoking rates among patients with primary depressive disorders and/or those using antidepressant medications, which were determined in univariate analysis in the current study, have been previously reported [20, 30, 31, 36]. Although it may be difficult to explain, the fact that the majority of our patients who were not using antidepressants were using antipsychotics may partially explain the relatively lower smoking rates among patients using antidepressant medications. In addition, the apparently beneficial effects of smoking observed in patients treated with antipsychotics are lacking among patients treated with antidepressants. In the other hand, except of bupropion and nortriptyline, evidence suggests that most antidepressants has no antismoking effect [45].

Several clinical guidelines recommend giving higher priority to providing smoking-cessation advice in everyday clinical practice to patients with a mental health diagnosis [46‐48]. A recent systematic review found that people with severe mental illness receive smoking-cessation advice about as often as people without mental illness do, whereas those with non-severe mental illness are slightly more likely to receive smoking-cessation advice compared with people without mental illness [48]. In addition to the benefits of smoking cessation in decreasing morbidity and mortality in people with psychiatric disorders [46], smoking cessation is also associated with reduced depression, anxiety, and stress, and improved positive mood and quality of life to the same extent for those with psychiatric disorders as for those without [49]. The big positive effect-size after smoking cessation in both those with or without psychiatric disorders may indicate the common personal and social motives of smoking in both groups [49]. However, traditional smoking-cessation programs may need to be tailored to fit the neuropsychological profile of psychiatric patients [50]. The European Psychiatric Association provides seven recommendations regarding the core components of the diagnostics and treatment of tobacco dependence in adults with mental illness [46]: (1) the process for recording smoking status, (2) the timing of the intervention, (3) counseling, (4) drug treatment using a first-line product (e.g., nicotine replacement therapy, varenicline, bupropion), (5) contacting the patient soon after cessation, (6) follow-up visits, and (7) relapse prevention and management [46].

The current study makes several important contributions. It is the first study in Saudi Arabia to estimate the gender-specific prevalence of current smoking and to determine its independent risk factors among male and female psychiatric patients. The mixed population and the relatively large sample size enabled us to examine the association of current smoking with a wide variety of psychiatric disorders and psychotropic medications. Previous studies focused primarily on antipsychotics and rarely on the variability of smoking rates among patients taking different groups of psychotropic medications. However, we acknowledge several limitations. First, the use of convenience sampling may limit the generalizability of our findings to psychiatric patients in Saudi Arabia. The cross-sectional design did not enable us to ascertain causality between psychiatric disorders or psychotropic medications and current smoking. Finally, although cigarette smoking is by far the most common type of smoking in Saudi Arabia, the findings of the current study do not reflect other types of tobacco smoking.

We found a high prevalence of current smoking among a large sample of psychiatric patients in Saudi Arabia. As in the general population, there is a striking gender difference in smoking rates. In addition to sociodemographic risk factors for smoking, substance abuse, psychotic disorders, and antipsychotic medications are strong independent associates. The current findings suggest an urgent need for smoking-cessation programs for these vulnerable patients as well as for further studies to test the effectiveness of such programs.