Different levels of lack of improvement at 4 weeks of escitalopram treatment as predictors of poor 8-week outcome in MDD

BackgroundSeveral post-hoc studies have shown that lack of early improvement reduces the chance of later response or remission. This post-hoc analysis evaluates different cut-off points of non-improvement at 4 weeks of escitalopram treatment to predict 8-week non-response and non-remission.MethodThis study consisted of MDD patients with an absence of improvement (<30% reduction in baseline score of the HAMD-17) at Week 4 of escitalopram treatment (10 mg/day) that continued escitalopram treatment (10–20 mg/day) for a further 4-week period (n=251). Predictive, sensitivity and specificity values for the several definitions of non-improvement (≤25%, ≤20% and ≤15% reduction in the HAMD-17 baseline total score) at 4 weeks were calculated.ResultsOverall, 70.1% (176/251) of patients did not achieve response at Week 8 and 84.5% (212/251) did not achieve remission. The predictive value for non-response was high (71.4–74.3%) for all cut-off points of non-improvement tested. The respective values for non-remission were placed between 85.0% and 87.2%.LimitationsThis was a post-hoc subgroup analysis. The only drug assessed was escitalopram.ConclusionsOur data indicate that an absence of improvement, <30% reduction in the HAMD-17, after 4 weeks of escitalopram treatment should prompt clinicians to consider a change in treatment strategy. Similar findings were previously reported for other antidepressants.