PERL Continuous Glucose Monitoring (CGM) Study

Study Summary

Seven-point capillary profiles have shown that mean glucose correlates with both diabetic retinopathy and nephropathy risk. However, there remains great controversy as to whether the degree of variability around mean glucose may also contribute to these microvascular complications. The PERL trial (NCT02017171), testing whether treatment with allopurinol can slow down kidney function loss in type 1 diabetes, provides a unique opportunity to assess the role of glycemic variability in the progression of diabetic kidney disease in individuals who already have mild to moderate kidney disease. By applying Continuous Glucose Monitoring (CGM) in the PERL Study population, the investigators will be able to better understand how metrics of glycemia (mean, time above and below range, and various measures of variability) are associated with renal outcomes in the PERL population as a whole, but also in important subgroups (e.g., albuminuric vs. normoalbuminuric subjects with ongoing GFR decline, allopurinol vs. placebo arms). The nvestigators also aim to obtain precise information on the range of blood glucose corresponding to any given HbA1c value in this population since previous studies generally excluded patients with renal disease.

Primary Outcome

Glomerular filtration rate (GFR) at the end of the PERL trial, measured by the plasma clearance of non-radioactive iohexol (iGFR) and adjusted for the iGFR at baseline.

Interventions

• OTHER Mean blood glucose
• OTHER Blood glucose CV
• OTHER % time 70-180 mg/dL
• OTHER % time below 54 mg/dL
• OTHER % time above 180 mg/dL