Predictors of Change in Skin Intrinsic Fluorescence in Type 1 Diabetes: The Epidemiology of Diabetes Complications Study

Background: Skin intrinsic fluorescent (SIF) scores are indirect measures of advanced glycation end-products (AGEs). SIF scores are cross-sectionally associated with type 1 diabetes (T1D) complications such as increased albumin excretion rate (AER), coronary artery calcification (CAC) and neuropathy. We assessed predictors of SIF score change in those with T1D. Methods: Data from the 30-year longitudinal Epidemiology of Diabetes Complications (EDC) study of childhood-onset T1D were used to assess AGEs measured with a SIF score produced by the SCOUT DS (R) device. SIF scores were assessed twice in 83 participants: between 2007-08 and again between 2010-14. Regression analyses were used to assess independent predictors of SIF score change. Results: At baseline, mean age was 47.9 +/- 6.9 years, diabetes duration was 36.7 +/- 6.4 years, and median glycosylated hemoglobin (HbA1c) was 7.1 (interquartile range: 6.5, 8.5). During a mean follow-up of 5.2 +/- 0.9 years, mean change in SIF score was 2.9 +/- 2.8 arbitrary units. In multivariable linear regression models, log HbA1c (P < 0.001), log estimated glomerular filtration rate (eGFR) (P < 0.001), overt nephropathy (defined as AER >= 200 mu g/min, P = 0.06), and multiple daily insulin shots/pump use (MDI) exposure years (P = 0.02) were independent predictors of SIF score change. Conclusions: Increases in SIF score over 5 years were related to increased glycemic levels and decreased kidney function (eGFR). MDI and glomerular damage were related to a decreased SIF score. This is one of the first studies with repeated SIF assessments in T1D and provides unique, albeit preliminary, insight about these associations.