Course of depression, health services costs, and work productivity in an international primary care study.

The Longitudinal Investigation of Depression Outcomes (LIDO) Study examined the outcomes and economic correlates of previously untreated depression among primary care patients in Barcelona, Spain; Be'er Sheva, Israel; Melbourne, Australia; Porto Alegre, Brazil; St. Petersburg, Russia; and Seattle, USA. Across all sites, 968 patients with current depressive disorder completed assessments of depression severity (Composite International Diagnostic Interview and Center for Epidemiologic Studies Depression Scale) at baseline and 9 months, and assessments of health services utilization and work days missed at baseline, 9 months, and 12 months. Follow-up depression status was characterized as persistent depression (n=345), partial remission (n=283), or full remission (n=340). At each site, patients with more favorable depression outcomes had fewer days missed from work; however, this relationship did not reach the 5% level of statistical significance at any site, and reached the 10% significance level only at Porto Alegre. Patients with more favorable depression outcomes also had lower health services costs, but this relationship reached the 5% significance level only in St. Petersburg. While the lack of statistical precision does not permit definitive conclusions, our findings are consistent with recent studies showing that recovery from depression is associated with lower health services costs and less time missed from work due to illness.