Substance Use Disorders in Elderly Admissions to an Academic Psychiatric Inpatient Service over a 10-Year Period.

Objective . There is a paucity of research on substance use disorders (SUDs) in the elderly psychiatric population. This study examines SUDs in a geriatric psychiatry inpatient service over a 10-year period. Methods . Data from 1788 elderly psychiatric inpatients from a ten-year period was collected. Variables collected included psychiatric diagnoses, SUD, number of psychiatric admissions, and length of stay. Those with and without a SUD were compared using Chi-Square or Student's t -test as appropriate using SPSS. Results . 11.7% ( N = 210) of patients had a SUD, and the most common substance was alcohol at 73.3% ( N = 154) or 8.6% of all admissions. Other SUDs were sedative-hypnotics (11%), opiate (2.9%), cannabis (1%), tobacco (1.4%), and unspecified SUD (38.6%). SUD patients were significantly younger, divorced, male, and less frequently readmitted and had shorter lengths of stay. The most common comorbid diagnoses were major depression (26.1%), bipolar disorder (10.5%), and dementia (17.1%). Conclusions . Over 10% of psychogeriatric admissions were associated with a SUD, with alcohol being the most common. Considering the difficulties in diagnosing SUD in this population and the retrospective study design, the true prevalence in elderly psychiatric inpatients is likely higher. This study adds to sparse literature on SUD in elderly psychiatric patients.