Incidence and prognostic significance of depressive symptoms in peripheral artery disease

Background-We compared the incidence of depression, defined by a Geriatric Depression Score (GDS) >6, between people with versus without peripheral artery disease (PAD). We determined whether depressive symptoms were associated with increased mortality in people with and without PAD. Methods and Results-Nine hundred and fifty-one PAD patients and 478 non-PAD patients were recruited from Chicago medical centers and followed prospectively. At baseline and annually, participants completed the GDS (0-15 scale, score >6-depression) and 6-minute walk. Cause of death was confirmed with death certificates. The prevalence of a GDS >6 at baseline was 186/951 (19.6%) among PAD versus 63/478 (13.2%) among non-PAD participants (P>0.003). During a mean follow-up of 2.71.2 years, 122/712 (17.1%) of participants with PAD versus 51/403 (12.7%) without PAD developed a GDS >6 (P-0.047). Adjusting for age, sex, race, comorbidities, and other confounders, PAD participants had an increased rate of developing a GDS >6 compared to non- PAD participants (hazard ratio>1.54 (95% CI-1.05-2.25, P-0.026). This association was not statistically significant after adjusting for 6-minute walk (P>0.258). Among PAD participants, a baseline GDS >6 was associated with increased all-cause mortality, adjusting for confounders (hazard ratio-1.57, 95% CI-1.12-2.21, P-0.009). This association was not significant after adjusting for 6-minute walk (P-0.224). Conclusions-People with PAD have a higher incidence of depressive symptoms than people without PAD. In PAD, depressive symptoms are associated with increased all-cause and cardiovascular mortality. These associations are explained in part by poorer 6-minute walk among people with PAD and among depressed people with PAD, respectively.