Mental Health
Pharmacotherapy guideline concordance for major depressive disorder and its link to functioning via symptom change Mason T. Breitzig* Mason Breitzig Fan He Lan Kong Guodong Liu Daniel A. Waschbusch Jeff D. Yanosky Erika F. H. Saunders Duanping Liao
Background: Alleviation of symptom severity for major depressive disorder (MDD) is known to precede a lagged improvement of functioning. However, the degree to which adherence to pharmacotherapy guideline recommendations is associated with this recovery process remains unclear. This study investigated whether greater pharmacotherapy guideline concordance (quantified by the GCA-8) is associated with better functioning via reducing MDD symptom severity.
Methods: Data from 1,403 adults (67% female, 85% non-Hispanic/Latino White, mean age of 43 years) with non-psychotic MDD from the Penn State Psychiatry Clinical Assessment and Rating Evaluation System (PCARES) registry (visits from February 1, 2015, to April 13, 2021) were eligible for analyses. Cross-sectional mediation analysis was used to explore the total, direct, and mediated effects of the association between the GCA-8 and World Health Organization Disability Assessment Schedule 2.0 (WHODAS; score standard deviation [SD]: 10.32), with Patient Health Questionnaire depression module (PHQ-9) scores as the mediator. Analyses were adjusted for sociodemographic and clinical characteristics.
Results: The total effect from mediation analysis indicated that a 1 SD increase in patients’ GCA-8 score (representing better concordance) was associated with a 0.53 improvement in patients’ 1-year mean WHODAS score (n=851; β=-0.53; P value=.01). Additionally, 96.6% (95% CI: [31.1%, 100.0%]; β=-0.51; P value=<.001) of the total effect was mediated by the change in MDD symptom severity. The direct effect of the GCA-8 on the mean WHODAS score, independent of PHQ-9 change, was nonsignificant (β=-0.02, P value=.92).
Conclusions: We cross-sectionally observed that higher pharmacotherapy guideline concordance is associated with better self-reported functioning in patients with MDD, possibly via improvement of MDD symptom severity; future research should employ longitudinal designs with repeated measurements to elucidate the directionality.