LAUSR

PURPOSE/BACKGROUND Daily treatment with sertraline improves functional impairment among individuals with premenstrual dysphoric disorder (PMDD). We do not know whether treatment initiated at symptom onset also improves functional impairment. METHODS/PROCEDURES This 3-site, double blind, randomized, clinical trial compared sertraline (25-100 mg) to similar appearing placebo, both administered at symptom onset, for reduction of PMDD symptoms. Ninety participants were allocated to sertraline and 94 participants to placebo. Functional outcomes from the Daily Ratings of the Severity of Problems included (1) reduced productivity or efficiency at work, school, home, or daily routine; (2) interference with hobbies or social activities; and (3) interference with relationships. Items were measured from 1 (no interference) to 6 (extreme interference) and averaged for the final 5 luteal phase days. This secondary analysis examined whether improvement in functional domains was greater for those allocated to sertraline compared with placebo. Second, we used causal mediation analyses to explore whether specific PMDD symptoms mediated functional improvement. RESULTS/FINDINGS Only relationship functioning improved significantly with active treatment between baseline and the end of the second cycle (active group mean [SD] change, -1.39 [1.38]; placebo group mean change, -0.76 [1.20]; β = -0.40; SE, 0.15; P = 0.009). The total effect of treatment on interference was -0.37 (95% confidence interval [CI], -0.66 to -0.09; P = 0.011). Given the nonsignificant direct effect (0.11; 95% CI, -0.07 to 0.29; P = 0.24) and significant indirect effect (-0.48; 95% CI, -0.71 to -0.24; P < 0.001), amelioration of anger/irritability likely mediated reductions in relationship interference. IMPLICATIONS/CONCLUSIONS That anger/irritability mediates impairments in relationship functioning has face validity but should be replicated in other data sets. TRIAL REGISTRATION ClinicalTrials.gov identifier NCT00536198.