Relationship between depressive symptoms and hypogonadism in men with COPD

The prevalence of depression in chronic obstructive pulmonary disease (COPD) is greater than in the general population, but the mechanism is unknown. Depression has been linked mechanistically to testosterone deficiency, and testosterone deficiency (hypogonadism) affects many men with COPD. Accordingly, we hypothesized that significant depressive symptoms would be associated with hypogonadism in men with COPD. The hypothesis was tested in a prospective cross-sectional investigation of 104 men (FEV1 = 43 ± 1% predicted (± SE)), 36 of whom had significant depressive symptoms (Geriatric Depression Scale score or GDS ≥ 11). Hypogonadism was present in 14 patients with GDS ≥ 11 (39%) and in 21 with GDS < 11 (31%; p = 0.41). The independent association between depressive symptoms and gonadal state was evaluated after adjusting for potential confounders: combined severity of lung disease and functional impairment (BODE-index), co-morbidities (Charlson co-morbidity-Index), age, active smoking, education, and marital status. After controlling for confounding variables, multivariable logistic-regression analysis revealed that only BODE-index (odds ratio 1.40; p = 0.003), lack of companion (2.73; p = 0.045) and younger age (0.93; p = 0.021) were independently associated with depressive symptoms. In a secondary analysis, patients were stratified into those with severe depressive symptoms (GDS ≥ 19) and those with mild depressive symptoms (GDS 11-18). Prevalence of hypogonadism was greater in first group than in the second (62% vs. 26%; p = 0.036). After controlling for confounders, however, gonadal state was not associated with severe depressive symptoms. Similarly, gonadal state was not associated with mood and motivation subscale scores of the GDS. In conclusion, presence of significant depressive symptoms was not associated with hypogonadism in men with COPD.