Gender differences in health-related quality of life in patients with bipolar disorder

Abstract

Health-related quality of life (HRQOL) is a widely accepted measure of illness state that is related to morbidity and mortality. Findings from various populations show that women report lower HRQOL than men. We analyzed baseline HRQOL data for gender differences from a multisite, randomized controlled study for adults with bipolar disorder. HRQOL was assessed using the 12-item Short Form (SF-12) physical component summary (PCS) and mental component summary (MCS) health scales. Multivariate linear and bivariate regression models examined differences in self-reported data on demographics, depressive symptoms (nine-item Patient Health Questionnaire), bipolar disorder symptoms (Internal State Scale), and medical comorbidities. Out of 384 enrolled (mean age = 42 years), 256 were women (66.7 %). After controlling for sociodemographic characteristics and clinical factors, women had lower SF-12 PCS scores than men [β = -1.78, standard error (SE) = 0.87, p < 0.05], indicating worse physical health, but there were no gender differences in MCS scores. After controlling for patient factors including medical and behavioral comorbidities, the association between gender and PCS score was no longer significant. Of the medical comorbidities, pain was associated with lower PCS scores (β = -4.90, SE = 0.86, p < 0.0001). Worse physical HRQOL experienced by women with bipolar disorder may be explained by medical comorbidity, particularly pain, suggesting the importance of gender-tailored interventions addressing physical health conditions.