Severely mentally ill substance abusers: an 18-month follow-up study

Abstract

Background: The aims of this study were to investigate initial characteristics and improvement after 18 months in patients with comorbidity of severe mental illness and substance dependence. These patients took part in a multicentre study aimed at improving co-operation between psychiatric health care units and social services.

Methods: A total of 358 patients, 66% men, were included. There were four diagnostic subgroups: psychosis 29%, depression 17%, borderline personality disorder 23%, and other diagnoses of equal severity 31%. Initially and at follow-up the following measurements were used: global functioning axis V DSM-III-R (GAF), seven areas of Addiction Severity Index (ASI) and psychological symptoms (SCL-90). The outcome of substance use during the past 6 months was estimated by the Clinical Rating Scale (CRS).

Results: Most patients were single (77%) and few (10%) had income from employment. Many (61%) had made suicide attempts, and 52% had somatic diseases before entering this project. After 18 months, 14 patients (3.9%) had died, and 288 patients (84%) could be interviewed. There were significant improvements in all but one ASI area (employment), in psychological symptoms and in global functioning. There was a positive correlation between the reductions in severity of alcohol abuse, drug abuse, psychiatric symptoms, relationships (ASI) and psychological symptoms. Forty-eight percent of patients with mainly alcohol-related problems, and 57% of those with mainly drug-related problems were either "abstinent" or using drugs "without impairment" (CRS) after 18 months. Improvement did not differ between psychiatric subgroups.

Conclusion: These patients have weak social integration. Alcohol dependence was the most common substance use disorder. In most areas investigated, patients had improved. No substance abuse was found in half of the patients at follow-up.