The effect of depression and proteinuria on the all‑cause and cardiovascular disease mortality among adults: a retrospective cohort study

Background The influence of both proteinuria and depression on mortality in the population is unclear. Methods This study included participants who had a urinary albumin-to-creatinine ratio and completed the Patient Health Questionnaire-9 from NHANES 2007 to 2018. The follow-up period spanned from the date of initial diagnosis until death or December 31, 2019, when the study period concluded. Proteinuria was defined as a urinary albumin-to-creatinine ratio of ≥ 30 mg/g, while depression was defined as a PHQ-9 score of ≥ 10. Four groups were classified based on the presence of proteinuria and depression. Results A total of 25109 individuals aged ≥ 20 years were included in the study. A total of 2211 deaths, including 554 due to cardiovascular disease, were recorded during a median follow-up of 7.08 years (range: 4.00-10.08). Participants with both depression and proteinuria had a significantly higher risk of all-cause mortality and CVD death (HR: 2.589, 95% CI: 1.922–3.488, P < 0.001; HR: 2.174, 95% CI: 1.312-3.600, P = 0.003) compared to those without either condition, even after adjusting for all covariates. Conclusions Our findings suggest that individuals with both depression and proteinuria have a significantly increased risk of all-cause mortality and cardiovascular death.