Hypoglycemia unawareness in type 1 diabetes patients using intermittent continuous glucose monitoring: Identification of risk factors and glycemic patterns

Abstract

BackgroundHypoglycemia unawareness designates failure to detect eminent hypoglycemia. Clarke's questionnaire is one of the most used systems to evaluate this problem. AimsTo relate Clarke's questionnaire (QQ) results with continuous glucose monitoring data. MethodsApplication of the questionnaire in a sample of type 1 diabetes mellitus (T1DM) patients using intermittent continuous glucose monitoring (iCGM). Results111 T1DM patients were evaluated, 56.8% female, mean age 35.0 ± 12.4 years and mean disease duration 18.8 ± 10.5 years.According to CQ, 13.5% had unawareness, 76.6% awareness and 9.9% indeterminate awareness to hypoglycemia. Those with unawareness had longer disease duration (25.1 ± 10.4 vs 18.2 ± 10.3 for awareness and 14.9 ± 9.9 for indeterminate awareness, p = 0.047), more time below range (10.3 ± 4.9% vs 6.3 ± 5.1 and 6.3 ± 4.8; p = 0.009) and higher mean duration of hypoglycemia (131.7 ± 38.6 vs 116.6 ± 49.6 and 131.7 ± 38.6; p = 0.008). In multivariate analysis, mean duration of hypoglycemia was an independent predictor of CQ results. In a receiver operating curve (AUC 0.746; p = 0.004) a mean duration of hypoglycemia ≥106.5 min showed 84.6% sensitivity/64.4% specificity for unawareness. ConclusionsOur sample had a significative prevalence of hypoglycemia unawareness which increased with longer diabetes duration. iCGM data can be indicative of this problem, with a mean hypoglycemia duration ≥106.5 min being suggestive, albeit unspecific.