Sex differences in residual somatic symptoms in patients with first-episode depression after acute-phase treatment

Background Residual somatic symptoms (RSS) are common in depressed patients, predicting treatment effectiveness. However, sex differences in RSS have received little systematic study. This study was conducted to compare sex differences of RSS in patients with first-episode depression (FED). Methods Nine hundred eighty-two patients with FED were selected and treated for 8 to 12 weeks. We evaluated the subjects' socio-demographic characteristics and residual depressive symptoms. Using the Patient Health Questionnaire-15 (PHQ-15) scale to assess residual somatic symptoms, the Sheehan Disability Scale (SDS) for the assessment of patients' function, the Quality of Life Enjoyment and Satisfaction Questionnaire-Short Form (Q-LES-Q-SF) for quality of life. Results The incidence of RSS with FED was 46.4%. For patients with residual symptoms, the age and age of onset in females were higher than males, but males had more years of education than females. The degree of "stomach pain" in females was more severe than in males, while "trouble sleeping" in males was more severe than that in females. Multiple regression analysis showed that the total Q-LES-Q-SF score was an independent influencing factor of RSS in both males and females, while the total SDS score only affected female RSS. Conclusions The prevalence of RSS in FED after acute-phase treatment is high. The symptom of "stomachache" is more pronounced in females, while "trouble sleeping" is more severe in males. Quality of life plays an essential role in RSS in both genders. Thus, sex needs to be considered when assessing the relationship between RSS and therapeutic effect in depression.