Purpose: The association of type 2 diabetes with proteinuria remission and renal function decline in patients with idiopathic membranous nephropathy (IMN) remains elusive. This study was designed to assess such association.
Methods: In this retrospective cohort study, we included 656 IMN patients treated with immunosuppressants or plus corticosteroids, of whom 72 were diagnosed as type 2 diabetes prior to or at diagnosis of IMN. Data on age, sex, body mass index, presence of hypertension and diabetes, laboratory tests, and therapeutic regimens were retrospectively retrieved from medical record. Cox regression was used to analyze risks of failure to achieve remission, relapse, and developing a ≥ 30% decline in estimated glomerular filtration rate (eGFR) or end-stage renal disease (ESRD) associated with baseline diabetes.
Results: The patients were followed for 36.6 (IQR 17.5-59.0) months, of whom 451 reached complete remission, 92 achieved partial remission, and 61 developed a ≥ 30% eGFR decline or ESRD. IMN relapse occurred in 30.6% of the 543 remitted patients. Baseline diabetes was associated with failure to achieve complete remission (HR 0.61, 95% CI 0.43-0.86, P = 0.005) in patients with IMN, independently of age, sex, hypertension, baseline serum albumin, urine protein levels, and eGFR, and therapeutic regimens. However, we failed to identify independent association between baseline diabetes and failure to achieve total remission (HR 0.85, 95% CI 0.63-1.1, P = 0.29), IMN relapse (OR 0.92, 95% CI 0.49-1.7, P = 0.80), or ≥ 30% decline in eGFR or ESRD (HR 1.4, 95% CI 0.78-2.7, P = 0.24) in patients with IMN.
Conclusions: Baseline diabetes may be independently associated with failure to achieve complete remission, but not with IMN relapse and renal function decline in IMN patients.
Keywords: Calcineurin inhibitors; Membranous nephropathy; Non-diabetic kidney disease; Type 2 diabetes.