Interactive Effects of Serum Leptin Levels and Physical Comorbidity on the Pharmacotherapeutic Response of Depressive Disorders

Interactive Effects of Serum Leptin Levels and Physical Comorbidity on the Pharmacotherapeutic Response of Depressive Disorders

Objective: To investigate individual and interactive associations of baseline serum leptin levels and physical comorbidity with short- and long-term treatment outcomes in outpatients with depressive disorders who received stepwise antidepressant treatment in a naturalistic prospective study design. Methods: Baseline serum leptin levels were measured, and the number of concurrent physical disorders ascertained from 1,094 patients. These patients received initial antidepressant monotherapy; then, for patients with an insufficient response or who experienced uncomfortable side effects, treatment was administered using alternative strategies every 3 weeks in the acute treatment phase (at 3, 6, 9, and 12 weeks) and every 3 months in the continuation treatment phase (at 6, 9, and 12 months). Then, 12-week and 12-month remission, defined as a Hamilton Depression Rating Scale score of ≤7, was estimated. Results: In multivariable logistic regression analyses, individual effects were found only between higher baseline serum leptin levels and 12-week non-remission. Significant interactive effects between higher leptin levels and fewer physical disorders (＜ 2 physical disorders) on 12-week non-remission were observed. However, neither individual nor interactive effects between leptin levels and physical comorbidity were associated with 12-month remission. Conclusion: The combination of serum leptin level and number of physical disorders may be a useful predictor of short-term treatment responses in patients with depressive disorders receiving pharmacotherapy.