Increase in the duration of antidepressant treatment from 1994 to 2003: A nationwide population-based study from Finland

Objective: We examined the length and continuity of antidepressant treatment and factors associated with long-term of treatment among adults. Methods: Nationwide data from all reimbursed antidepressant prescriptions in 1994-2003 were linked with patients' data retrieved from Statistics Finland and the Finnish Hospital Discharge Register. Logistic regression models were used to analyse long term use of antidepressants. Results: The annual prevalence of antidepressant use increased from 3.6% in 1994 to 7.3% in 2003. Short-term use (<3-months) decreased from 58% in 1995 to 51% in 2000 and long-term treatment (≥12 months) increased from 18 to 21%. In 2000, 31% of treatment periods lasted ≥6 months and 24% ≥9 months. Long-term treatment correlated to the purchase of other psychotropics, in-patient psychiatric care, and prescription by a psychiatrist. Conclusions: Treatment periods with antidepressants have become longer over time. Clinical factors related to mental disorder severity predict long-term use. Only a quarter had the treatment duration recommended by clinical guidelines for depression.