Suboptimal duration of antidepressant treatments in the older ambulatory population of Quebec: association with selected physician characteristics.

Objectives: To assess the association between selected physician characteristics and suboptimal duration of antidepressant use in the older outpatient population.

Design: Follow-up of patients who were prescribed an antidepressant treatment by a cohort of physicians in Quebec.

Setting: Community-based older outpatient population in Quebec.

Participants: Retrospective cohort of 1,301 general practitioners (GPs) and 236 psychiatrists followed from 1991 to 1997.

Measurements: Treatment duration of less than 180 days in 1996/97.

Results: Premature interruption of antidepressant treatment was very frequent (44.7%). GPs, physicians who practice in metropolitan or urban regions, and those who have a proportion of older patients in their practice of less than 50% show a higher rate of premature interruption. These associations could not be accounted for by the choice of products, dosage, or patient characteristics.

Conclusion: We have identified physician characteristics that are associated with suboptimal duration of antidepressant use and conclude that further interventions should target subgroups of physicians.