Early Pulse Pressure and Low-Grade Proteinuria as Independent Long-Term Risk Factors for New-Onset Diabetes Mellitus After Kidney Transplantation

Risk factors for new-onset diabetes after transplantation (NODAT) need to be assessed in large cohorts.
We retrospectively evaluated the impact of early (3 and 6 months after transplantation) proteinuria, urinary albumin excretion (UAE) and arterial pressure on NODAT in 828 Causasian renal transplant recipients (median follow-up: 5.3 years; 5832 patient-years).
The 10- and 20-year incidence of NODAT was 15.0% and 22.0%, respectively. Low-grade (<1 g/day) (HR: 2.04 [1.25–3.33], p = 0.0042) and very low-grade (<0.3 g/day) (HR: 2.21 [1.32–3.70], p = 0.0025) proteinuria were independent risk factors for NODAT. There was a dose-dependent relationship across UAE categories (increasing risk from normoalbuminuria to macroalbuminuria) with NODAT. Tacrolimus, sirolimus and beta-blockers (HR: 1.86 [1.07–3.22], p = 0.0277) were significantly associated with NODAT even after multiple adjustments, but not diuretics, angiotensin-converting enzyme inhibitors or angiotensin-receptor blockers. Systolic arterial pressure (HR per 10 mmHg: 1.16 [1.03–1.29], p = 0.0126) and pulse pressure (HR: 1.26 [1.12–1.43], p = 0.0002) were associated with NODAT. Only pulse pressure remained significant after adjustments. Patients at highest risks had early proteinuria and pulse pressure >60 mmHg.
Early low-grade proteinuria and pulse pressure (in addition to beta-blockers) constitute independent risk factors for NODAT; they may be markers of the metabolic syndrome and/or vascular damage in renal transplant recipients.