Duration of untreated illness and outcomes in unipolar depression: A systematic review and meta-analysis

To systematically review evidence of the effects of the duration of untreated depression on the clinical outcomes of patients suffering from Unipolar Major Depression. A systematic review and meta-analysis of the evidence of duration of untreated depression and the effect it has on clinical outcomes in Unipolar Major Depression. Data used to this purpose were obtained from a literature search of the MEDLINE, Psychoinfo and Embase databases. Comparable data extracted from studies were entered and analysed using Cochrane Collaboration's Review Manager software Version 5.2. Ten studies were identified as meeting the inclusion criteria. Only three studies reported comparable data and were consequently used for the meta-analysis. Pooled data indicates the overall positive effect of shorter duration of untreated illness both in a patient's response to treatment (RR 1.70) and remission (RR 1.65). Other studies which were not included in the meta-analysis confirmed the importance of reducing delays in the treatment of depression in order to prevent the risk of worse outcomes and chronicity, in particular in patients presenting with a first episode of depression. Data regarding the association between the duration of untreated episode in recurrent depression and clinical outcomes are less evident. The heterogeneity of the selected studies was cause for limitations with regard to the carrying out of adequate meta-analysis. There is evidence highlighting the importance of a reduced no-treatment interval for patients suffering Unipolar Depression. In particular, there is emphasis on the first episode of depression corresponding to the notion of reducing the duration of untreated illness.