Insulin use in chronic kidney disease and the risk of hypoglycemic events

We examined in persons with type 2 diabetes (T2D) whether the use of insulin and the risk of serious hypoglycemic events with insulin is higher in persons with more advanced CKD.

In a national cohort of 855,133 veterans with T2D seen at Veteran Affairs clinics between Jan 1, 2008 and December 31, 2010 with at least two serum creatinine measurements, we defined insulin use from pharmacy records and serious hypoglycemic events by ICD-9/10 codes from emergency room visits or hospitalizations that occurred until December 31, 2016.

Mean age was 66 ± 11 years and 97% were men. Mean baseline eGFR was 73 ± 22 ml/min/1.73 m². In a multivariable Cox regression model of those without insulin use at baseline (N = 653,200), compared to eGFR ≥90 group, eGFR < 30 group had higher hazard (HR 1.80, 95% CI 1.74 to 1.88) of subsequent insulin use. In a multivariable Cox model with propensity score matching for baseline insulin use (N = 305,570), both insulin use (HR 2.34, 95% CI 2.24 to 2.44) and advanced CKD (HR 2.28, 95% CI 2.07 to 2.51 for comparison of eGFR < 30 to eGFR ≥90 ml/min/1.73 m² groups) were associated with increased risk of subsequent serious hypoglycemic events.

In T2D, more advanced CKD was associated with greater insulin use. Both insulin use and advanced CKD were risk factors for serious hypoglycemic events. The safety of insulin compared to newer glycemic agents in more advanced CKD needs further study.