Continued use of antidepressants among patients in ambulatory care

Depression and depressive symptoms have a relatively poor prognosis. Prophylactic maintenance treatment with antidepressants has only been recommended recently. Most studies of chronicity and relapses have been carried out with initially hospitalized patients or with patients attending psychiatric treatment facilities. All incident ambulatory antidepressant-treated patients (n=456) in a Swedish community during 1980-84 were identified. They were followed up for 8 years after the index date. Survival analysis was used to study chronic antidepressant use. Concomitant use of other prescription drugs was studied using generalized estimating equations regression analysis. More than half of the patients had one or several periods of antidepressant treatment after the index year. The relapse rate was between 23% and 33% for each year after the index year. Eleven per cent had continuous use every year after the index year. Patients with one or more relapses had a significantly higher number of other prescription drugs, as compared with those treated only once. Once antidepressant treatment has been initiated, the relapse rate is considerable. The high use of other prescription drugs indicated continued somatic and psychiatric health problems among recurrent users. There is a need for long-term outcome studies of antidepressant treatment in the population, particularly in view of the increased sales after introduction of the selective serotonin reuptake inhibitors.