Supplementary Material for: Prediabetes in Children and Adults with Glomerular Disease

Background: Glomerular disease (GD) and diabetic nephropathy are both leading causes of end-stage kidney disease (ESKD) in the United States. Much is known about each individually, but less of any interactions between the two. There is emerging evidence that factors specific to glomerular disease, such as immunosuppression, may increase the risk of diabetes, which in turn could compound glomerular filtration rate (GFR) decline through the mechanisms of diabetic nephropathy. Understanding the epidemiology of prediabetes and diabetes in glomerular disease patients may inform improved screening and prevention practices in this population and may lead to strategies that mitigate progression to ESKD. The aim of this study is to delineate risk factors for prediabetes in glomerular disease. Methods: Data was extracted from University of Michigan and Kidney Research Network electronic health record registry with patients classified by age at glomerular disease at diagnosis or first nephrology appointment (child (age<18y, n=406) and adult (≥ 18y, n=339)). A Cox proportional hazards model was calculated using prediabetes after kidney disease onset as the outcome, adjusted for age, sex, race, weight, hypertension, and defined relevant drug prescriptions. A subgroup analysis was performed to track the progression from prediabetes to diabetes. Results: 148 patients (19.9% of cohort) developed prediabetes in study follow-up. Adult GD patients were more likely than pediatric GD patients to progress (HR: 1.73 [95%CI: 1.19 - 2.50]), as were patients with uncontrolled hypertension (HR: 9.61 [95%CI: 3.02 - 30.61]) and controlled hypertension (HR: 6.50 [95%CI: 1.91 - 22.18]). The use of beta blockers, statins, or diuretics was also associated with higher prediabetes risk (HR: 2.87 [95%CI: 1.98 - 4.17]). Conclusions: Adult age, worsening control of hypertension, and certain medications were associated with increased prediabetes risk in pre-existing glomerular disease. More data, in particular prospective data, is needed to refine risk relationships and incidence data.