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Substance Use Disorders Among Inpatients with Bipolar Disorder and Major Depressive Disorder in a General Hospital
Substance Use Disorders Among Inpatients with Bipolar Disorder and Major Depressive Disorder in a General Hospital Chao-Cheng Lin, M.D., Ya-Mei Bai, M.D., Pei-Gi Hu, M.D., and Hong-Shiow Yeh, M.D. Abstract: The prevalence and type of substance abuse and dependence were determined for 49 patients with mood disorders on a general hospital psychiatric unit. A standardized diagnostic interview was conducted with a high value of interrater reliability. This study found that 18.4% of mood disorder inpatients met the diagnostic criteria for psychoactive substance use disorders by DSM-III-R. Sedatives-hypnoticsanxiolytics was the most common substance use disorder (10.2%), followed by alcohol (6.1%). Patients with major depression had a higher rate of comorbidity with substance use disorders than did the bipolar disorder patients (p 5 0.011). The prevalence of sedatives-hypnotics-anxiolytics use disorder among major depression patients was 35.7%, which was higher than that among bipolar disorder patients (0%). Male patients had a significantly higher percentage of substance use disorders than did female patients (p 5 0.054). Seventy-seven percent of the patients with a dual diagnosis of mood and substance use disorder were not diagnosed as having substance use disorders by psychiatrists in charge. © 1998 Elsevier Science Inc.
Introduction Recent studies have revealed an increase in substance use disorders, not only in the general population, but also among psychiatric patients [1]. The prevalence rate has been reported to range from one-third to over one-half of psychiatric patients [2– 4]. Inpatients with mood disorders have been reported to have a higher prevalence of substance Department of Psychiatry, Yu-Li Veterans Hospital, Hua-Lien, Taiwan (C.-C. Lin, Y.-M. Bai); Department of Family Medicine, The 807 Military General Hospital, Taipei, Taiwan (P.-G. Hu); Department of Psychiatry, Veterans General Hospital-Taipei, Taiwan (H.-S. Yeh). Address reprint requests to: Ya-Mei Bai, M.D., Department of Psychiatry, Yu-Li Veterans Hospital, 91, Hsing-Hsing St., HuaLien, Taiwan, R.O.C.
98 ISSN 0163-8343/98/$19.00 PII S0163-8343(98)00003-6
abuse compared with other psychiatric inpatients [5,6]. The presence of substance abuse can significantly affect the course of psychiatric illness, the choice of treatment, and the patient’s response to treatment [2,7,8]. To our knowledge, however, little attention has been paid to the substance abuse in bipolar disorder and major depression in Taiwan. The current study attempted to quantitatively assess the lifetime prevalence of substance use disorders among inpatients with bipolar disorder and major depression hospitalized on a general hospital psychiatric unit. Further objectives were to identify the types of substances used and to relate substance use disorders to psychiatric diagnoses.
Methods Our sample consisted of 69 patients with mood disorders consecutively admitted to the 62-bed psychiatric inpatient unit at the Veterans General Hospital-Taipei between April and November 1994. The hospital services veterans mainly, but also the city population. Patients were included if they met DSM-III-R [9] criteria for bipolar disorder and major depression as diagnosed by the patients’ resident and attending psychiatrists. Patients were excluded from the sample if they were older than 65 years of age, had been given an equivocal Axis I diagnosis, or were suspected of suffering from an organic mental disorder. Approximately one week after admission, patients were interviewed by one of the four authors. The interviewer explained the purpose of the inquiry, advised patients that their participation was voluntary, and reassured them
General Hospital Psychiatry 20, 98 –101, 1998 © 1998 Elsevier Science Inc. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
Substance Use Disorders and Major Mood Disorders
that the information they gave would remain confidential. We administered a partially modified version of the portion of Structured Clinical Interview (SCID) for DSM-III-R, which deals with substance use disorders, including alcohol, sedativeshypnotics-anxiolytics, cannabis, stimulants, opioids, cocaine, hallucinogens, glue, and other substances. Nicotine was not included in our study. The validity and reliability of the SCID have been established as high [10]. The interview was delayed if the patient was still psychotic at that time. After the patients were discharged, their chart was reviewed to determine whether the psychiatrists in charge diagnosed them as having a substance use disorder. We examined the interrater reliability of our diagnosis of substance use disorders using SCID with a sample of 10 patients. The interrater reliability for the assessment of all classes of substance use disorders was high, with generalized kappa ranging from 0.85 to 1.0 between any two raters. The Chisquare test was used to compare the percentages of substance use disorders and drug of choice across diagnostic categories.
Results Twenty patients were dropped from the sample because they were too psychotic, refused the interview, or because they were discharged before the interview. The final sample consisted of 49 patients, including 17 men (33.3%) and 32 women (66.7%). The mean age of all subjects was 33.3 6 13.0 (15– 62) years. Thirty-eight percent of these patients were married. Thirty-five patients (70.9%) had bipolar disorders, 14 (29.2%) had major depression. Nine patients (18.4%) received a dual diagnosis of substance use and mood disorders; two of the nine patients were in remission for substance use disorders. Sedative-hypnotics-anxiolytics (10.2%) were the most frequent substances of abuse and dependence, followed by alcohol (6.1%) and stimulants (4.1%). One bipolar disorder and one major depression patient (4.1%) used more than one substance, including combinations of alcoholamphetamine and alcohol-benzodiazepine. These findings are summarized in Table 1. Forty-three percent of the major depression patients had a diagnosis of substance use disorder and 8.6% of the bipolar disorder patients had such a diagnosis. Patients with major depression had a higher rate of comorbidity with substance use disorders than did the bipolar disorder patients (p 5 0.011). The proportion of subjects with substance
Table 1. Proportion of subjects with substance use disorders by category of substance and type of disorder (n 5 49) Abuse (n) (%) Sedatives/hypnotics/ anxiolytics Alcohol Stimulants Others Total no. of cases
1 1 0 0 2
2.0 2.0 0 0 4.1
Dependence (n)
(%)
4 2 2 1 8
8.2 4.1 4.1 2.0 16.3
Total (n) (%)
5 3 2 1 9
10.2 6.1 4.1 2.0 18.4
use disorders according to the category of mood disorder is shown in Table 2. The prevalence of sedatives-hypnotics-anxiolytics use disorders among major depression patients was 35.7%, which was higher than that among bipolar disorder patients (0%). There was no difference in the prevalence of other substance use disorders among major depression and bipolar disorders. There were six males and three females among the nine cases of substance use disorders, and their mean age was 36.4 6 14.92 years. Male patients had a significantly higher percentage of substance use disorders than did female patients (37.5% and 12.5%, respectively; the p value of Fisher’s exact test, two-tailed, was 0.054). Only three of these cases were diagnosed as having a substance use disorder by psychiatrists in charge (33.3%).
Discussion Crowly et al. [3] reported that one-third of the patients in a psychiatric hospital had a concurrent Table 2. Proportion of subjects with substance use disorders by category of mood disorder
Substance use disorder Sedatives/hypnotics/ anxiolytics Alcohol Stimulants Others Total no. of casesa a
Major depression (n 5 14)
Bipolar disorder (n 5 35)
(n)
(%)
(n)
(%)
5 1 1 0 6
35.7 7.1 7.1 0 42.9
0 2 1 1 3
0 5.7 2.9 2.9 8.6
Fisher’s exact test, p 5 0.011.
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C.-C. Lin et al.
substance abuse problem. Brady et al. [11] found that 64% of psychiatric inpatients at a VA medical center had current or past substance abuse problems, but these researchers did not use standard diagnostic methods. Only 18% of the patients in our study had such problems, which is a lower rate than in most reports of other investigators. The data of the National Institute of Mental Health Epidemiologic Catchment Area study [6] indicated that bipolar affective disorder was the Axis I disorder most likely to be associated with some form of substance abuse or dependence. Brady et al. [11] found that 30% of patients with bipolar disorder (6 of 20) met current criteria for drug or alcohol abuse. Miller et al. [13] studied 60 bipolar patients by chart analysis and found that 25% of the patients abused one or more drugs (nicotine not included). The prevalence of substance use disorders (nicotine dependence excluded) in our bipolar patients was 8.6%, which is lower than in the above-mentioned reports. The reasons may be the lower prevalence of alcohol abuse or dependence in our sample and the lower prevalence of illegal substance abuse in Taiwan. Mueser et al. [12] reported a trend in patients with bipolar disorder: they have a higher rate of alcohol abuse (66%). Miller et al. reported on a study of 60 bipolar patients and found that 18% of the patients abused alcohol. However, only 5.7% of our bipolar patients had alcohol abuse or dependence, which is a much lower rate than in other reports. The reason is unknown, but it may be partly related to female predominance in our sample. The Epidemiologic Catchment Area (ECA) study [6] estimated that in the United States, the lifetime prevalence rate of substance use disorders in patients with unipolar major depression is 27.2%, which is lower than the prevalence rate of our study. The prevalence of sedatives-hypnoticsanxiolytics in major depression was high in our study, which might reflect the abuse potential of prescribed drugs in this group of patients. Prescribing of drugs in this group of patients needs careful evaluation in clinical practice. The reported prevalence rate of substance abuse among psychiatric patients varies widely from one facility to another. This variance may be partly due to inadequate screening methods, the fact that many patients do not report the extent of their substance use, they deliberately conceal their substance use, or they are too psychotic to give adequate histories [14]. Therefore, this study tried to enhance the reliability of the diagnosis by employ-
100
ing the following methods: 1) the study was crosssectional and the interviews were conducted by using standardized diagnostic assessment instruments, and our interrater reliability was high; 2) the patients were interviewed after psychotic symptoms had subsided. The present results reveal a high probability of substance use disorders among mood disorder inpatients. Epidemiological data from the general population in Taiwan is needed to determine whether the pattern of substance use among mood disorder patients is related to that of the general population. The missed diagnosis of substance use disorders was high in our study. A greater sensitivity and a systematic inquiry about substance use on admission should lead to an improved rate of accuracy in making diagnoses. Training protocols for the identification, assessment, treatment, and management of the patients with the dual diagnosis of mood disorder and substance use disorder should be developed. These steps would promote appropriate and more effective interventions for this challenging population. This study did not address whether the substance abuse preceded or followed the onset of mood disorders. It may be difficult to differentiate primary mood symptoms from consequences of substance abuse. The frequency of co-existence is too high to be a chance occurrence [1]. Patients found to have a dual diagnosis of mood and substance use disorder will be a good sample for further research into the psychopathology and course of both disorders and how they influence each other.
References 1. Ross HE, Glaser FB, Germanson T: The prevalence of psychiatric disorders in patients with alcohol and drug problems. Arch Gen Psychiatry 45L:1023–1031, 1988 2. Galanter M, Castaneda R, Ferman J: Substance abuse among general psychiatric patients-place of presentation, diagnosis and treatment. Am J Drug Alcohol Abuse 14(2):211–235, 1988 3. Crowley TJ, Chesluk D, Ditts S, Hart R: Drug and alcohol abuse among psychiatric admissions. Arch Gen Psychiatry 30:13–20, 1974 4. Ananth J, Vandewater S, Kamal M, Brodsky A, Bamal R, Miller M: Missed diagnosis of substance abuse in psychiatric patients. Hosp Community Psychiatry 40(3):297–299, 1989 5. Brady KT, Sonne SC: The relationship between substance abuse and bipolar disorder. J Clin Psychiatry 56(suppl 3), 19–24, 1995 6. Kessler RC, McGonagle KA, Zhao S, et al: Lifetime
Substance Use Disorders and Major Mood Disorders
7. 8.
9. 10.
and 12-month prevalence of DSM-III-R psychiatric disorders in the United States: results from the National Comorbidity Survey Arch Gen Psychiatry 51(1):8–19, 1994 Brady KT, Lydlard RB: Bipolar affective disorder and substance abuse. J Clin Psychopharmacol. 12(1):17s– 22s, 1992 Lehman AF, Myers CP, Corty E: Assessment and classification of patients with psychiatric and substance abuse syndromes. Hosp Community Psychiatry 40(10):1019–1025, 1989 American Psychiatric Association (1987) Diagnostic and Statistical Manual of Mental Disorders, 3rd ed. revised (DSM-III-R), Washington, DC. Williams JBW, Gibbon M, First MB, et al: The structured Clinical Interview for DSM-III-R (SCID) II.
11.
12.
13. 14.
Multisite test-retest reliability. Arch Gen Psychiatry 49:630–636, 1992 Brady KT, Casto S, Lydiard RB, Malcolm R, Arana G: Substance abuse in an inpatient psychiatric sample. Am J Drug Alcohol Abuse 17(4):389–397, 1991 Mueser KT, Yarnold PR, Bellack AS: Diagnostic and demographic correlates of substance abuse in schizophrenia and major affective disorder. Acta Psychiatr Scand 85:48–55, 1992 Miller FT, Busch F, Tanenbaum JH: Drug abuse in schizophrenia and bipolar disorder. Am J Drug Alcohol Abuse 15(3):291–295, 1989 Kanwischer RW, Hundley J: Screening for substance abuse in hospitalized psychiatric patients. Hosp Community Psychiatry 41(7):795–797, 1990
101
Introduction Recent studies have revealed an increase in substance use disorders, not only in the general population, but also among psychiatric patients [1]. The prevalence rate has been reported to range from one-third to over one-half of psychiatric patients [2– 4]. Inpatients with mood disorders have been reported to have a higher prevalence of substance Department of Psychiatry, Yu-Li Veterans Hospital, Hua-Lien, Taiwan (C.-C. Lin, Y.-M. Bai); Department of Family Medicine, The 807 Military General Hospital, Taipei, Taiwan (P.-G. Hu); Department of Psychiatry, Veterans General Hospital-Taipei, Taiwan (H.-S. Yeh). Address reprint requests to: Ya-Mei Bai, M.D., Department of Psychiatry, Yu-Li Veterans Hospital, 91, Hsing-Hsing St., HuaLien, Taiwan, R.O.C.
98 ISSN 0163-8343/98/$19.00 PII S0163-8343(98)00003-6
abuse compared with other psychiatric inpatients [5,6]. The presence of substance abuse can significantly affect the course of psychiatric illness, the choice of treatment, and the patient’s response to treatment [2,7,8]. To our knowledge, however, little attention has been paid to the substance abuse in bipolar disorder and major depression in Taiwan. The current study attempted to quantitatively assess the lifetime prevalence of substance use disorders among inpatients with bipolar disorder and major depression hospitalized on a general hospital psychiatric unit. Further objectives were to identify the types of substances used and to relate substance use disorders to psychiatric diagnoses.
Methods Our sample consisted of 69 patients with mood disorders consecutively admitted to the 62-bed psychiatric inpatient unit at the Veterans General Hospital-Taipei between April and November 1994. The hospital services veterans mainly, but also the city population. Patients were included if they met DSM-III-R [9] criteria for bipolar disorder and major depression as diagnosed by the patients’ resident and attending psychiatrists. Patients were excluded from the sample if they were older than 65 years of age, had been given an equivocal Axis I diagnosis, or were suspected of suffering from an organic mental disorder. Approximately one week after admission, patients were interviewed by one of the four authors. The interviewer explained the purpose of the inquiry, advised patients that their participation was voluntary, and reassured them
General Hospital Psychiatry 20, 98 –101, 1998 © 1998 Elsevier Science Inc. All rights reserved. 655 Avenue of the Americas, New York, NY 10010
Substance Use Disorders and Major Mood Disorders
that the information they gave would remain confidential. We administered a partially modified version of the portion of Structured Clinical Interview (SCID) for DSM-III-R, which deals with substance use disorders, including alcohol, sedativeshypnotics-anxiolytics, cannabis, stimulants, opioids, cocaine, hallucinogens, glue, and other substances. Nicotine was not included in our study. The validity and reliability of the SCID have been established as high [10]. The interview was delayed if the patient was still psychotic at that time. After the patients were discharged, their chart was reviewed to determine whether the psychiatrists in charge diagnosed them as having a substance use disorder. We examined the interrater reliability of our diagnosis of substance use disorders using SCID with a sample of 10 patients. The interrater reliability for the assessment of all classes of substance use disorders was high, with generalized kappa ranging from 0.85 to 1.0 between any two raters. The Chisquare test was used to compare the percentages of substance use disorders and drug of choice across diagnostic categories.
Results Twenty patients were dropped from the sample because they were too psychotic, refused the interview, or because they were discharged before the interview. The final sample consisted of 49 patients, including 17 men (33.3%) and 32 women (66.7%). The mean age of all subjects was 33.3 6 13.0 (15– 62) years. Thirty-eight percent of these patients were married. Thirty-five patients (70.9%) had bipolar disorders, 14 (29.2%) had major depression. Nine patients (18.4%) received a dual diagnosis of substance use and mood disorders; two of the nine patients were in remission for substance use disorders. Sedative-hypnotics-anxiolytics (10.2%) were the most frequent substances of abuse and dependence, followed by alcohol (6.1%) and stimulants (4.1%). One bipolar disorder and one major depression patient (4.1%) used more than one substance, including combinations of alcoholamphetamine and alcohol-benzodiazepine. These findings are summarized in Table 1. Forty-three percent of the major depression patients had a diagnosis of substance use disorder and 8.6% of the bipolar disorder patients had such a diagnosis. Patients with major depression had a higher rate of comorbidity with substance use disorders than did the bipolar disorder patients (p 5 0.011). The proportion of subjects with substance
Table 1. Proportion of subjects with substance use disorders by category of substance and type of disorder (n 5 49) Abuse (n) (%) Sedatives/hypnotics/ anxiolytics Alcohol Stimulants Others Total no. of cases
1 1 0 0 2
2.0 2.0 0 0 4.1
Dependence (n)
(%)
4 2 2 1 8
8.2 4.1 4.1 2.0 16.3
Total (n) (%)
5 3 2 1 9
10.2 6.1 4.1 2.0 18.4
use disorders according to the category of mood disorder is shown in Table 2. The prevalence of sedatives-hypnotics-anxiolytics use disorders among major depression patients was 35.7%, which was higher than that among bipolar disorder patients (0%). There was no difference in the prevalence of other substance use disorders among major depression and bipolar disorders. There were six males and three females among the nine cases of substance use disorders, and their mean age was 36.4 6 14.92 years. Male patients had a significantly higher percentage of substance use disorders than did female patients (37.5% and 12.5%, respectively; the p value of Fisher’s exact test, two-tailed, was 0.054). Only three of these cases were diagnosed as having a substance use disorder by psychiatrists in charge (33.3%).
Discussion Crowly et al. [3] reported that one-third of the patients in a psychiatric hospital had a concurrent Table 2. Proportion of subjects with substance use disorders by category of mood disorder
Substance use disorder Sedatives/hypnotics/ anxiolytics Alcohol Stimulants Others Total no. of casesa a
Major depression (n 5 14)
Bipolar disorder (n 5 35)
(n)
(%)
(n)
(%)
5 1 1 0 6
35.7 7.1 7.1 0 42.9
0 2 1 1 3
0 5.7 2.9 2.9 8.6
Fisher’s exact test, p 5 0.011.
99
C.-C. Lin et al.
substance abuse problem. Brady et al. [11] found that 64% of psychiatric inpatients at a VA medical center had current or past substance abuse problems, but these researchers did not use standard diagnostic methods. Only 18% of the patients in our study had such problems, which is a lower rate than in most reports of other investigators. The data of the National Institute of Mental Health Epidemiologic Catchment Area study [6] indicated that bipolar affective disorder was the Axis I disorder most likely to be associated with some form of substance abuse or dependence. Brady et al. [11] found that 30% of patients with bipolar disorder (6 of 20) met current criteria for drug or alcohol abuse. Miller et al. [13] studied 60 bipolar patients by chart analysis and found that 25% of the patients abused one or more drugs (nicotine not included). The prevalence of substance use disorders (nicotine dependence excluded) in our bipolar patients was 8.6%, which is lower than in the above-mentioned reports. The reasons may be the lower prevalence of alcohol abuse or dependence in our sample and the lower prevalence of illegal substance abuse in Taiwan. Mueser et al. [12] reported a trend in patients with bipolar disorder: they have a higher rate of alcohol abuse (66%). Miller et al. reported on a study of 60 bipolar patients and found that 18% of the patients abused alcohol. However, only 5.7% of our bipolar patients had alcohol abuse or dependence, which is a much lower rate than in other reports. The reason is unknown, but it may be partly related to female predominance in our sample. The Epidemiologic Catchment Area (ECA) study [6] estimated that in the United States, the lifetime prevalence rate of substance use disorders in patients with unipolar major depression is 27.2%, which is lower than the prevalence rate of our study. The prevalence of sedatives-hypnoticsanxiolytics in major depression was high in our study, which might reflect the abuse potential of prescribed drugs in this group of patients. Prescribing of drugs in this group of patients needs careful evaluation in clinical practice. The reported prevalence rate of substance abuse among psychiatric patients varies widely from one facility to another. This variance may be partly due to inadequate screening methods, the fact that many patients do not report the extent of their substance use, they deliberately conceal their substance use, or they are too psychotic to give adequate histories [14]. Therefore, this study tried to enhance the reliability of the diagnosis by employ-
100
ing the following methods: 1) the study was crosssectional and the interviews were conducted by using standardized diagnostic assessment instruments, and our interrater reliability was high; 2) the patients were interviewed after psychotic symptoms had subsided. The present results reveal a high probability of substance use disorders among mood disorder inpatients. Epidemiological data from the general population in Taiwan is needed to determine whether the pattern of substance use among mood disorder patients is related to that of the general population. The missed diagnosis of substance use disorders was high in our study. A greater sensitivity and a systematic inquiry about substance use on admission should lead to an improved rate of accuracy in making diagnoses. Training protocols for the identification, assessment, treatment, and management of the patients with the dual diagnosis of mood disorder and substance use disorder should be developed. These steps would promote appropriate and more effective interventions for this challenging population. This study did not address whether the substance abuse preceded or followed the onset of mood disorders. It may be difficult to differentiate primary mood symptoms from consequences of substance abuse. The frequency of co-existence is too high to be a chance occurrence [1]. Patients found to have a dual diagnosis of mood and substance use disorder will be a good sample for further research into the psychopathology and course of both disorders and how they influence each other.
References 1. Ross HE, Glaser FB, Germanson T: The prevalence of psychiatric disorders in patients with alcohol and drug problems. Arch Gen Psychiatry 45L:1023–1031, 1988 2. Galanter M, Castaneda R, Ferman J: Substance abuse among general psychiatric patients-place of presentation, diagnosis and treatment. Am J Drug Alcohol Abuse 14(2):211–235, 1988 3. Crowley TJ, Chesluk D, Ditts S, Hart R: Drug and alcohol abuse among psychiatric admissions. Arch Gen Psychiatry 30:13–20, 1974 4. Ananth J, Vandewater S, Kamal M, Brodsky A, Bamal R, Miller M: Missed diagnosis of substance abuse in psychiatric patients. Hosp Community Psychiatry 40(3):297–299, 1989 5. Brady KT, Sonne SC: The relationship between substance abuse and bipolar disorder. J Clin Psychiatry 56(suppl 3), 19–24, 1995 6. Kessler RC, McGonagle KA, Zhao S, et al: Lifetime
Substance Use Disorders and Major Mood Disorders
7. 8.
9. 10.
and 12-month prevalence of DSM-III-R psychiatric disorders in the United States: results from the National Comorbidity Survey Arch Gen Psychiatry 51(1):8–19, 1994 Brady KT, Lydlard RB: Bipolar affective disorder and substance abuse. J Clin Psychopharmacol. 12(1):17s– 22s, 1992 Lehman AF, Myers CP, Corty E: Assessment and classification of patients with psychiatric and substance abuse syndromes. Hosp Community Psychiatry 40(10):1019–1025, 1989 American Psychiatric Association (1987) Diagnostic and Statistical Manual of Mental Disorders, 3rd ed. revised (DSM-III-R), Washington, DC. Williams JBW, Gibbon M, First MB, et al: The structured Clinical Interview for DSM-III-R (SCID) II.
11.
12.
13. 14.
Multisite test-retest reliability. Arch Gen Psychiatry 49:630–636, 1992 Brady KT, Casto S, Lydiard RB, Malcolm R, Arana G: Substance abuse in an inpatient psychiatric sample. Am J Drug Alcohol Abuse 17(4):389–397, 1991 Mueser KT, Yarnold PR, Bellack AS: Diagnostic and demographic correlates of substance abuse in schizophrenia and major affective disorder. Acta Psychiatr Scand 85:48–55, 1992 Miller FT, Busch F, Tanenbaum JH: Drug abuse in schizophrenia and bipolar disorder. Am J Drug Alcohol Abuse 15(3):291–295, 1989 Kanwischer RW, Hundley J: Screening for substance abuse in hospitalized psychiatric patients. Hosp Community Psychiatry 41(7):795–797, 1990
101