Background and Purpose: Drug and alcohol abuse is a problem for individuals with severe mental illness which can profoundly limit recovery from psychiatric disability. Despite its broadly-accepted significance, little is known about longitudinal patterns of substance use across diagnostic categories of mental health conditions. Studies suggest a high prevalence of substance abuse exists among individuals with affective and psychotic conditions. However, patterns of use, drug preference, and the functional impact of use may vary considerably between individuals with affective and psychotic conditions, which could have implications for social work treatment development efforts. This study investigated the longitudinal prevalence and preference of substance use in a large sample of individuals with affective and psychotic conditions followed 1-year post-hospital discharge, and the differential trajectories of 1-year functional recovery among individuals with comorbid substance use.
Methods: 785 individuals with an affective (74%) or a psychotic (26%) condition were studied as part of the MacArthur Violence Risk Assessment Study. Substance use and functional outcome data were gathered every 10-weeks for 1-year. Patterns of use and drug preference were analyzed using descriptive statistics; c2 tests were employed to examine differences between diagnostic groups. Subsequently, a series of individual growth curve analyses were conducted to examine differential 1-year functional outcome trajectories between substance misusing participants with affective and psychotic conditions.
Results: Of the 785, 70% (N = 549) reported using drugs and/or alcohol over 1-year. Alcohol (78.9%) was the most common substance used, followed by marijuana (38.5%), and cocaine (36.2%). There were no significant differences in patterns of alcohol or marijuana use between individuals with affective or psychotic conditions (all p > .197), however individuals with affective conditions did exhibit more frequent sedative use, c2 (1, N = 785) = 5.88, p = .01. Results from linear growth models indicated that participants with psychotic conditions consistently attributed less problems to their use of substances than participants with affective conditions F (1, 731) = 9.32, p = .002. Yet, individuals with psychotic conditions showed significantly less improvement in global functioning over 1-year compared to individuals with affective conditions F (5, 2444) = 3.26, p = .006.
Conclusions and Implications: Many individuals with affective and psychotic conditions misuse substances and little variation exists in patterns of use between diagnostic groups, which signals a need for social work interventions among these populations. Individuals with psychosis are less likely to attribute problems to their use of substances even though they experience the greatest disability from use. Unfortunately, there are few substance abuse treatment options for individuals with psychosis. Social work must take a leading role in developing the next generation of psychosocial treatment options for individuals with psychotic conditions who misuse substances.
