Reassessing the Link: Depression and Diabetic Nephropathy in Type 2 Diabetes Mellitus Patients: Insights From the...

Background: Type 2 diabetes mellitus (T2DM) patients with depression are often accompanied by diabetic nephropathy. However, limited prospective studies have investigated the independent association between depression and diabetic nephropathy, as well as its progression among T2DM patients. This study aims to investigate the association between depression and the development or progression of diabetic nephropathy in T2DM patients, utilizing data from the ACCORD Health-Related Quality of Life (HRQL) study. Methods and Results: The nine-item Patient Health Questionnaire (PHQ-9) was utilized to assess depressive symptoms at baseline, and at 1, 3, and 4 years. The primary outcomes included deterioration of renal function, macroalbuminuria, and microalbuminuria. The changes in renal function were evaluated using estimated glomerular filtration rate (eGFR). As the severity of depression, measured by the PHQ-9, increased, there was no corresponding rise in the risk of deterioration in renal function (HR, 1.00; 95% CI, 0.98-1.01), macroalbuminuria (HR, 0.99; 95% CI, 0.53-1.86), or microalbuminuria (HR, 1.00; 95% CI, 0.97-1.03) per unit increase in PHQ-9 score. The estimated unadjusted eGFR (mL/min/1.73 m²) decline over the entire study period did not significantly differ for each 1-year increase in age (none: 2.21, 95% CI 1.98-2.44; ever depression: 2.51, 95% CI 2.36-2.67; persist depression: 2.28, 95% CI 1.99-2.57; all pairwise p-values > 0.05). Conclusions: T2DM patients with depression do not demonstrate lower renal function or an increased rate of renal function decline. Moreover, they do not exhibit a heightened risk of renal function deterioration, macroalbuminuria, or microalbuminuria compared to T2DM patients without depression.