What is the association between quality of treatment for depression and patient outcomes? A cohort study of adults consulting in primary care

BackgroundThe association between adequate treatment for a Major Depressive Episode (MDE) and improvements in depressive symptoms is not well established in naturalistic practice conditions. The main objective of this study was to examine the association between receiving at least one minimally adequate treatment for MDE (i.e. according to clinical guidelines) in the previous 12 months and evolution of depressive symptoms at 6- and 12-months. Associations with receiving pharmacotherapy and/or psychotherapy and the role of severity of depression were examined.MethodsThis cohort study included 908 adults meeting criteria for previous-year MDE and consulting at one of 65 primary care clinics in Quebec, Canada. Multilevel analyses were performed.ResultsResults show that (i) receiving at least one minimally adequate treatment for depression was associated with greater improvements in depression symptoms at 6 and at 12 months; (ii) adequate pharmacotherapy and adequate psychotherapy were both associated with greater improvements in depression symptoms, and (iii) the association between adequate treatment and improvement in depression symptoms varied as a function of severity of symptoms at the time of inclusion in the cohort with worse symptoms at the time of inclusion being associated with greater reductions at 6 and 12 months.LimitationsMeasures are self-reported. Participants were recruited at different stages over the course of their MDE.ConclusionsThis study shows that adequate treatment for depression is associated with improvements in depressive symptoms in naturalistic primary care practice conditions, but that those with more severe depressive symptoms are more likely to receive adequate treatment and improve across time.