Association between incident depression and clinical outcomes in patients with chronic kidney disease.

Background: Depression is highly prevalent and related to increased morbidity and mortality in patients on dialysis, but less is known among patients with earlier stages of CKD. This study investigated the associations between depression and clinical outcomes in patients with CKD not receiving dialysis. Methods: We identified 157 398 adults with CKD stages 3-5 not previously diagnosed with depression from the Stockholm CREAtinine Measurements (SCREAM) project. The primary outcomes included hospitalization, CKD progression (>40% decline in eGFR, initiation of kidney replacement therapy, or death due to CKD), major adverse cardiovascular events (MACE; myocardial infarction, stroke, or cardiovascular death), and all-cause mortality. Survival analyses were used to estimate the associations between incident depression and adverse health outcomes, adjusting for socio-demographics, kidney disease severity, healthcare utilization, comorbidities, and concurrent use of medications. Results: During a median follow-up of 5.1 (interquartile range: 2.3-8.5) years, 12 712 (8.1%) patients received an incident diagnosis of depression. A total of 634 471 hospitalizations (4 600 935 hospitalized days), 42 866 MACEs, and 66 635 deaths were recorded, and 9795 individuals met the criteria for CKD progression. In the multivariable-adjusted analyses, incident depression was associated with an elevated rate of hospitalized days [rate ratio: 1.77, 95% confidence interval (CI): 1.71-1.83], as well as an increased rate of CKD progression [hazard ratio (HR): 1.38, 95% CI: 1.28-1.48], MACE (HR: 1.22, 95% CI: 1.18-1.27), and all-cause mortality (HR: 1.41, 95% CI: 1.37-1.45). The association with CKD progression was more evident after one year of depression diagnosis (HR: 1.47, 95% CI: 1.36-1.59). Results were robust across a range of sensitivity analyses. Conclusion: Among patients with nondialysis-dependent CKD stages 3-5, incident depression is associated with poor prognosis, including hospitalization, CKD progression, MACE, and all-cause mortality.