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

We examined the length and continuity of antidepressant treatment and factors associated with long-term of treatment among adults.

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.

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.

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.