Introduction: Diabetes is a major risk factor for chronic kidney disease (CKD). Previous studies have shown contradictory results regarding the effect of prediabetes in the development of CKD.
Methods: We performed a secondary analysis of the SPRINT trial (Systolic Blood Pressure Intervention Trial) involving 9361 patients without diabetes and with an increased cardiovascular risk (clinical or subclinical cardiovascular disease, estimated glomerular filtration rate [eGFR] 2060 ml/min per 1.73 m2, 10-year Framingham score ≥15%, or age ≥75 years). We divided patients according to fasting glucose into two groups: normoglycemia (fasting glucose <100 mg/dl) and prediabetes (fasting glucose ≥100 mg/dl). In non-CKD patients, we assessed the incidence of CKD (decrease in eGFR ≥30% to <60 ml/min per 1.73 m2) and the incidence of albuminuria (doubling of the ratio of albumin/creatinine from <10 mg/g to >10 mg/g). In patients with CKD, we evaluated the incidence of a decrease in the eGFR ≥50%, the incidence of albuminuria and the development of end-stage renal disease (ESRD) requiring dialysis or kidney transplantation. We used Cox proportional hazard models to estimate hazard ratios (HR) adjusting for age, sex, race, systolic blood pressure, BMI, smoking, prior cardiovascular disease, statin and aspirin use, and trial treatment arm.
Results: In the SPRINT trial, 5425 (58.2%) patients had normoglycemia and 3898 (41.8%) had prediabetes. The prevalence of CKD was similar between groups (29.1% in normoglycemia vs 27.4% in prediabetes, P=0.09). During a median follow-up of 3.26 years, there were 164 (1.8%) patients with incident CKD and 245 (2.6%) with incident albuminuria among non-CKD patients. In patients with CKD, there were 21 (0.2%) patients with a decrease in the eGFR ≥50%, 108 (1.2%) with incident albuminuria and 16 (0.2%) requiring dialysis or kidney transplantation. The adjusted HR for incidence of CKD in patients with prediabetes compared with normoglycemic patients was 1.02 (0.731.42, P=0.91) and for incident albuminuria in non-CKD patients was 1.06 (0.801.39, P=0.69). Among patients with CKD at baseline, the adjusted HR for decrease in the eGFR ≥50% in prediabetes compared with normoglycemia was 1.64 (0.644.22, P=0.30), for incident albuminuria was 0.89 (0.571.39, P=0.61), and for the development of ESRD requiring dialysis or kidney transplantation was 0.45 (0.121.66, P=0.23).
Conclusions: In the SPRINT trial, prediabetes was not associated with a higher incidence of CKD, incident albuminuria or worsening of kidney function. Prediabetes does not appear to be a relevant risk factor for development or progression of CKD.
19 May 2018 - 22 May 2018