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 Table of Contents  
ORIGINAL RESEARCH REPORT
Year : 2020  |  Volume : 17  |  Issue : 2  |  Page : 24-29

Clinical correlates of tobacco use among hospitalized psychiatric patients


1 Department of Psychiatry, King George’s Medical University, Lucknow, Uttar Pradesh, India
2 Department of Geriatric Mental Health, King George’s Medical University, Lucknow, Uttar Pradesh, India

Date of Submission04-Dec-2018
Date of Acceptance19-Feb-2020
Date of Web Publication14-May-2020

Correspondence Address:
Dr. Sujita Kumar Kar
Department of Psychiatry, King George's Medical University, Lucknow, Uttar Pradesh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jcls.jcls_95_18

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  Abstract 


Introduction: Recently concluded the National Mental Health Survey found the prevalence of tobacco use disorder to be 20.9% in adults (male = 32.8% and female = 9.8%). The burden of tobacco use disorder is higher in patients with mental illnesses, which significantly affects the treatment outcome. The aim of the study was to estimate the prevalence of tobacco use in psychiatry in-patients of a tertiary care hospital in North India and to compare sociodemographic and clinical parameters between tobacco users and nonusers. Methods: This is a cross-sectional, observational study conducted on psychiatric in-patients of a tertiary care hospital in North India. Retrospective chart review of patients with age ≥ 15 years was done. Data were extracted in a semi-structured pro forma. Comparison of sociodemographic and clinical parameters between tobacco users and nonusers was done using an appropriate statistical tool. Results: The study sample consisted of 303 psychiatric in-patients, of which 121 (39.9%) of patients were tobacco users (males = 58.85% and females = 7.21%). Among tobacco users, 52% were primarily suffering from severe mental disorders, 29% from common mental disorders. Tobacco users had a higher number of psychiatric comorbidities and comorbid other substance use disorders than tobacco nonusers. Comorbid alcohol use (38%) and cannabis use (34%) were also high in the tobacco user group. Those using tobacco were significantly less adherent to treatment.Conclusion: Tobacco use is seen in 2/5th of the psychiatric in-patients. High psychiatric comorbidity and poor treatment adherence are more common among tobacco users.

Keywords: Comorbidity, psychiatric illness, tobacco use


How to cite this article:
Kar SK, Roy P, Dalal PK. Clinical correlates of tobacco use among hospitalized psychiatric patients. J Clin Sci 2020;17:24-9

How to cite this URL:
Kar SK, Roy P, Dalal PK. Clinical correlates of tobacco use among hospitalized psychiatric patients. J Clin Sci [serial online] 2020 [cited 2020 May 29];17:24-9. Available from: http://www.jcsjournal.org/text.asp?2020/17/2/24/284281




  Introduction Top


Tobacco use disorder is a global health concern. It is anticipated that by 2025, there will be 1.1 billion current tobacco smokers, globally and tobacco use will take the form of an epidemic in many low- to middle-income countries.[1] As per the global statistics on addictive behaviors (status report 2014), it is projected that approximately 11% of males and 6% of females die every year due to tobacco.[2] Global adult tobacco survey was conducted over 3 billion individuals from 14 low- and middle-income countries, including India, from 2008 to 2010.[3] The prevalence of tobacco use was found to be 48.6% in men and 11.3% in women.[3]

Tobacco use disorder is the most common form of substance use disorder in India. The recently concluded the National Mental Health Survey (2015–2016), funded by the Ministry of Health and Family Welfare, Government of India, had revealed the prevalence of tobacco use disorder to be more than 20% community population sample.[4] There is a gross variation in the prevalence of tobacco use across the states of India.[5]

The prevalence of tobacco use disorder (smoking) is found to be 2–4 times higher among patients with psychiatric disorders, including other substance use disorders.[6] The presence of comorbid psychiatric disorders in tobacco users attribute to relapses and persistence of tobacco use despite efforts to quit.[6] High mental health morbidity and substance use disorders are reported in youths with tobacco use disorder.[7] Female tobacco users have more internalizing mental illnesses than their male counterparts.[7] Youth tobacco users commonly have comorbid mood and anxiety disorders.[8] Smokers are also more likely have comorbid psychotic disorders.[9] Patients with psychiatric disorders often smoke to downgrade their psychiatric symptoms.[9] Chronic smoking also influences the life expectancy in patients with severe mental disorders such as – schizophrenia.[9] Patients with attention-deficit hyperkinetic disorder, bipolar affective disorder, and depression consume tobacco in higher rates then healthy individuals.[9] The report of the National Institute of Mental Health mentions about increased rate of smoking in individuals with anxiety disorders, depression, and schizophrenia, which attributes to the higher rates of morbidity and mortality in these individuals.[10] In the national comorbidity survey, it was found that the smoking rates in patients with current mental illness to be highest followed by those individuals with life-time mental illness and those having no psychiatric illness.[11],[12] The smoking rate of individuals, who are having mental illness currently, is nearly double than the smoking rate in persons with no psychiatric illness.[11] Evidence from animal studies suggest that psychiatric disorders as vulnerability factor for tobacco addiction.[13] Tobacco use also influences the outcome of comorbid disorders; however, clinicians often ignore the tobacco use-related issues while treating the comorbid condition.[14]

Smoking significantly influences the metabolism of psychotropic medications. Nicotine being a hepatic cytochrome enzyme inducer, increases the metabolism of psychotropic medications, thereby decreasing their efficacy.[15] The efficacy of antidepressants, antipsychotics, and benzodiazepines are commonly affected by smoking.[15]

Among the Indian population, there are cultural as well as geographical variations in the extent and pattern of tobacco use. Many people in India consume tobacco in the chewable form. There is poor regulation of tobacco use and selling through the existing law due to inadequate implementation and monitoring.[5] Hence, unrestrained use of tobacco is a big challenge in India. This study aimed to explore the prevalence of tobacco use in psychiatry in-patients of a tertiary care hospital in North India and to compare sociodemographic and clinical parameters between tobacco users and nonuser groups in these patients.


  Methods Top


This is a cross-sectional, observational study conducted on psychiatric in-patients of a tertiary care hospital in North India. Data of patients hospitalized in a particular unit from August 2013 to July 2018, as obtained from the patients, their caregivers, hospital assessment, and treatment records, were analyzed. Patients who had been hospitalized primarily for a psychiatric illness (except tobacco use disorders) were included. The reasons for hospitalization were management, certification, or medicolegal reasons. The diagnoses had been made as per the ICD-10, diagnostic criteria for research diagnostic criteria, and appropriate management administered following standard treatment protocols. Retrospective chart review of patients aged over 15 years was done; thereby, sociodemographic, and clinical data were extracted in a semi-structured pro forma. If the subject had used a substance within 30 days of assessment, it was categorized as “Current use.” The analysis of the extracted data was done using an appropriate statistical tool.


  Results Top


Sociodemographic profile of the sample

During the 5-year period (August 2013–July 2018), a total of 303 patients were hospitalized in a specific unit of the department of psychiatry of a tertiary care teaching hospital of North India. The study population consisted of 192 males and 111 female patients with mental illness. Among the 303 patients, 131 patients (43.2%) had comorbid substance use disorders, including tobacco. One hundred and twenty-one (39.93%) of them were current tobacco users. Among the tobacco users, 93.4% were male (n = 113) and 6.6% were female (n = 8). The prevalence of tobacco use (current) among males was 58.85%, whereas among females the prevalence was 7.21%.

The mean age of patients who used tobacco was 35.24 ± 13.56 years, and that of nonusers was 29.53 ± 11.94 years, which was significantly different from each other (P = 0.001). Most of the subjects in both groups had education up to primary school (35.5% of tobacco users and 28.6% of tobacco nonusers). About 50% of tobacco users and 59% of nonusers belonged to nuclear family. Three patients each in both the groups were prison inmates who had been referred to the department for psychiatric assessment and management. More than half (57.85%) of the tobacco users were currently employed as compared to nonusers (20.3%). Majority of the patients in both groups (88% in tobacco users vs. 82% in nonusers) were Hindu by religion. About 1/4th (24%) of tobacco using in-patients had a current psychosocial stressor reported to be associated with the current episode of illness, while about 1/3rd (31%) of patients in the other group had an association with a stressor; however, the difference was not significant (P = 0.197). About 12% of patients in both groups had a positive family history of psychiatric illness.

Clinical profile of the sample

The prevalence of substance use

Among the patients, who were currently using tobacco (n = 121), comorbid substance use was no table, 38% were using alcohol, about 34% were using cannabis, 10% were using opioids, and 3% were using benzodiazepines. About 43% (n = 52) of tobacco users had no other comorbid substance use, whereas 57% (n = 69) had comorbid other substance use. Of these patients having comorbid substance use, 36.4% (n = 44) patients had one comorbid substance use, 14% (n = 17) patients had used two other substances, 5.8% (n = 7) had used three other substances, while 0.8% (n = 1) the patient had a history of four comorbid substance use. Among the tobacco nonusers (n = 182), 172 (94.5%) patients had no comorbid substance use; 6 (3.3%) of them had used alcohol, 2 (1.09%) of them had use of cannabis, 2 (1.09%) had use of opioids, and 3 (1.6%) of them had abuse of other substances (benzodiazepines, Lysergic acid diethylamide (LSD), antidepressants). Eight subjects (4.4%) in this group had used one substance other than tobacco, and one patient (0.55%) each had use of two and four other substances, respectively. Tobacco users had statistically significantly higher prevalence of comorbid substance use as compared to nonusers (P ≤ 0.00001).

Diagnosis of and treatment adherence for primary psychiatric illness

The primary psychiatric illnesses for which these patients had been admitted were classified into four types: Severe mental illness (schizophrenia, persistent delusional disorder, schizoaffective disorder, other nonorganic psychotic disorder, unspecified psychosis, manic episode, and bipolar affective disorder) common mental illness (depression, anxiety disorders, obsessive–compulsive disorder, and stress-related disorders), other psychotic mental illness (acute and transient psychotic disorders, organic psychosis, and substance-induced psychotic disorder), and other nonpsychotic mental illness (mental retardation, substance use disorders, personality disorder, and dementia). As shown in [Table 1], most patients in both the groups were suffering from severe mental illnesses in both the groups, and there was no statistically significant difference in the distribution of primary psychiatric illnesses between tobacco users versus nonusers. Forty percent of tobacco users (n = 49) had been diagnosed with single primary psychiatric illness and 60% (n = 72) of tobacco users had more than one comorbid psychiatric illness. When the number of primary psychiatric illnesses in individual patients of both groups was compared, tobacco users had significantly higher number of psychiatric comorbidities (P ≤ 0.00001). Of the 121 tobacco using patients, 74 (61%) were on treatment for their psychiatric illness(es), while 115 (63%) of tobacco nonusers were on treatment for the same. Comparison of treatment adherence pattern showed that 48.6% of these tobacco users who were on drug treatment were adherent to treatment; while, 74% of the tobacco nonusers on drug treatment were adherent to their treatment. The difference was statistically significant (P = 0.0004). Rest were having erratic adherence to treatment.
Table 1: Distribution of Primary psychiatric illnesses in study population

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Comorbid medical illnesses

Among the tobacco users, the most common medical comorbidity was infective illnesses (10.7%), followed by metabolic diseases (9%), neurological disorders (7.4%), chronic obstructive pulmonary disease (COPD) (6.6%), and anemia (3.3%); other medical disorders were seen in 4.95%. Of the tobacco-using sample, 11.6% (n = 14) were suffering from more than one medical comorbidities, 37.2% (n = 45) had one medical comorbidity and 51.2% (n = 62) had none. In the group of tobacco nonusers, 13.15% (n = 24) had multiple medical comorbidities, 36.3% (n = 66) were suffering from one medical comorbidity and 50.55% (n = 92) did not have any medical comorbidity. There was no statistically significant difference in this respect between these two groups. However, on comparison of the distribution of the various categories of comorbid medical illnesses, tobacco nonusers were found to be suffering from significantly higher number of infective illnesses, anemia, metabolic as well as neurological disorders (P = 0.0101).


  Discussion Top


This cross-sectional, observational study of psychiatric in-patients of a tertiary care teaching hospital in North India was conducted with the objective to study the prevalence, sociodemographic and clinical correlates of tobacco use in subjects hospitalized for their primary psychiatric ailments. Those admitted during the 5-year period (2013–2018) of the study in a particular unit of the department were included. Study subjects were of age ≥15 years, and data collection was through retrospective chart review, and a total of 303 patients were included. Of them, the current prevalence of tobacco use was about 40% (n = 121). The prevalence rate of our study is comparable to that of Chandra et al., who had studied the prevalence and correlates of tobacco use, including dependence in a psychiatric inpatient setting of a tertiary care mental hospital of South India.[16] They found the prevalence of tobacco use to be 36%. A study conducted by Gupta et al., in North India in 2016 reported that 50.8% of all psychiatry outpatients were currently (in the past 1 month) abusing one or more substances such as tobacco, alcohol, cannabis, opioid, and benzodiazepines.[17] However, the above study estimated the prevalence of all substances, including tobacco. If all substances are considered in our study, 43.2% of patients had comorbid substance use disorder (including tobacco). As the inpatients stay in a more restricted setting, so the access to substances including tobacco gets limited which might be responsible for variation in the prevalence rates of tobacco use among psychiatric inpatients and outpatients.

In our study, the prevalence of tobacco use among male patients was about 8 times higher as compared to that of female patients (58.85% vs. 7.21%, P ≤ 0.00001). This difference in male-female prevalence is representative of the sociodemographic characteristics of the Indian general population. A meta-analysis by Reddy and Chandrashekar showed a similar difference in substance abuse prevalence between men (11.9/1000) and women (1.7/1000).[18] Ninety-eight percent of the female patients (109 out of 111) of our sample were homemakers, students, or unemployed and thereby, not financially independent to access substances of abuse. Chandra et al., in their study, had also reported a higher prevalence of any type of tobacco use among male patients (53%) than female patients (9%) and also reported the association of male gender with the current tobacco dependence.[16] Another study conducted by Gupta et al., at the psychiatry outpatient department of a multispecialty hospital in North India over a period of 3 months, in patients aged 18–65 years, showed 6 times higher prevalence of the current tobacco use in male patients than female patients (24.8% vs. 4.42%).[17] The findings of our study are comparable to these previous studies.

More than half (57.85%) of the tobacco users in our study were employed as compared to tobacco nonusers (20.3%). Economic independence associated with employment can be attributed for the easier procurement of substances, and hence, statistically higher rate of employment in tobacco users (P ≤ 0.00001). The use of tobacco is very common in the settings of the workplace in India. Most people working as laborers, shopkeepers, drivers, carpenters use tobacco during work. Sharing of tobacco is common among workmates in India. This might be the reason for high prevalence of tobacco among people who are employed. An Indian study report about the high prevalence of the current tobacco (both smoke and smokeless form) use among unskilled workers.[19] In addition, tobacco users and nonusers did not have statistically significant difference in distribution according to educational status and family type. In the study by Gupta et al. employed patients were found to be consuming more tobacco (P < 0.001) than unemployed patients.[17] Unmarried patients consumed more tobacco (P = 0.029) than married. Education and living arrangement were not found to be related to substance abuse. However, Chandra et al. found that nicotine dependence was more likely among older, less-well-educated men.[16]

A notable proportion of the tobacco using in-patients in our study had comorbid substance use of one or more substances, the prevalence of overall comorbid substance use was significantly higher among tobacco users as compared to nonusers (P ≤ 0.00001). Alcohol was most common (38%), followed by cannabis (34%), followed by opioids and benzodiazepines. This similar pattern had been noted in an earlier study.[17] In their study, male current tobacco users used alcohol (15.4%) most commonly followed by cannabis (2.5%) and opioid (1.09%). This similar pattern had been reported by the National Household Survey[20],[21] indicating the current (1-month period) use of alcohol, cannabis, and opiates as 21.4%, 3%, and 0.7%, respectively, in general population. The difference in the prevalence of substance use disorders might be due to the difference in the composition of mental illnesses in the sample population in the studied clinical population. Similarly, studies on the general population have a different representation of sociodemographic variables than our study population, which might be attributing to the differences in prevalence rates.

Although there was no statistically significant difference in the distribution of comorbid psychiatric illnesses between tobacco users and nonusers, tobacco users had significantly higher number of psychiatric comorbidities (P ≤ 0.00001). The most common category of mental illness the tobacco using patients were primarily admitted for, was severe mental illnesses (52%), followed by Common mental illnesses (29%), followed by other psychotic mental illnesses (10%) and other nonpsychotic mental illnesses (8%). Comparable pattern was noticed in the tobacco nonusers. In an earlier Indian study, Gupta et al. found common mental disorders (major depressive disorder, anxiety, and stress-related disorders) to be the most common psychiatric comorbidity followed by severe mental disorders (Schizophrenia and related disorders and bipolar disorder).[17] Chandra et al. also concluded that there was no association between nicotine dependence and the specific psychiatric diagnoses represented in this sample.[16]

Medication adherence among the tobacco nonusers was significantly better than that of tobacco users (P = 0.0004) in our study. This indicates that, even though the patients were in contact with a treatment facility and were advocated treatment, patients using tobacco currently did not maintain adherence to the treatment. The current tobacco use can be considered as a predictor of medication nonadherence in psychiatric in-patients.

About half of the tobacco users as well as nonusers were suffering from one or more medical comorbidities. In this respect, it can be stated that medical comorbidities were fairly common in psychiatric in-patients included in our study, irrespective of tobacco using status. The most common medical comorbidity noted was infective illnesses (found in 10.7%). Metabolic diseases (9%) and neurological disorders (7.4%) were fairly common, followed by COPD (6.6%) and anemia (3.3%), while other medical illnesses were found in 4.95% of the tobacco users. Gupta et al. had also reported medical illnesses in their study population-jaundice was reported in 9.2%, hypertension and COPD in 9.3%, diabetes mellitus in 0.4%, sexually transmitted disorders in 0.7%, seizure disorder in 0.4% of the patients, and other medical disorders in 0.1%.[17] The findings in both our study and this study are comparable in this respect. In our study, tobacco nonusers were having significantly higher rate of anemia. This might be due to the reason of relatively higher proportion of females among tobacco nonuser group, and in India, anemia is common among the females, which explains our study findings.

Limitations

The patients and their accompanying caregivers were the providers who were information on substance use. No confirmatory tests such as urine drug screen were conducted. Thus, the status of substance use could have gone unrecognized in some patients. In addition, the exact pattern of tobacco use (form of tobacco used, age of onset, duration, frequency of use, amount used currently, etc.,) was not studied keeping in mind the objective of the study. Correlation with the severity of comorbid mental illness, including other substance use or other comorbid medical illness not studied. More exhaustive studies with stronger methodology can be planned in future keeping in view the emergence of tobacco use as a global hazard.


  Conclusion Top


The current use of tobacco among psychiatric in-patients was more common in males and among those patients who were employed currently. In addition, tobacco users had significantly higher prevalence of comorbid substance use as compared to tobacco nonusers and significantly higher number of primary psychiatric illnesses. Those using tobacco were less adherent to the prescribed treatment for psychiatric illnesses. Addressing the tobacco-related issues among the psychiatric inpatients is expected to improve the treatment outcome.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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