Impaired Fasting Glucose and Chronic Kidney Disease, Albuminuria, or Worsening Kidney Function: A Secondary Analysis of SPRINT

Abstract

Abstract Purpose Diabetes mellitus is a risk factor for the development and progression of chronic kidney disease (CKD). However, the association of prediabetes with adverse kidney outcomes is uncertain. Methods We performed a secondary analysis of the Systolic Blood Pressure Intervention Trial (SPRINT), including 9361 participants without diabetes at baseline. We categorized participants according to fasting glucose level as having impaired fasting glucose [≥100 mg/dL (≥5.6 mmol/L)] or normoglycemia [<100 mg/dL (<5.6 mmol/L)]. Unadjusted and adjusted proportional hazards models were fitted to estimate the association of impaired fasting glucose (vs normoglycemia) with a composite outcome of worsening kidney function [≥30% decrease in estimated glomerular filtration rate (eGFR) to <60 mL/min/1.73 m2 in participants without baseline CKD; ≥50% decrease in eGFR or need for long-term dialysis/kidney transplantation in participants with CKD] or incident albuminuria (doubling of urinary albumin/creatinine ratio from <10 mg/g to >10 mg/g). These outcomes were also evaluated separately and according to CKD status at baseline. Results Participants’ mean age was 67.9 ± 9.4 years, 35.5% were female, and 31.4% were black. The median follow-up was 3.3 years, and 41.8% had impaired fasting glucose. Impaired fasting glucose was not associated with higher rates of the composite outcome [hazard ratio (HR): 0.97; 95% CI: 0.8 to 1.16], worsening kidney function (HR: 1.02; 95% CI: 0.75 to 1.37), or albuminuria (HR: 0.98; 95% CI: 0.78 to 1.23). Similarly, there was no association of impaired fasting glucose with outcomes according to baseline CKD status. Conclusions Impaired fasting glucose at baseline was not associated with the development of worsening kidney function or albuminuria in participants of SPRINT.