Introduction: Impaired awareness of hypoglycemia (IAH) is a risk factor for severe hypoglycemia in type 1 diabetes (T1D) . Current tools to identify IAH are limited in their ability to characterize unawareness and evaluate hypoglycemia severity. The Hypoglycemia Awareness Questionnaire, including the 5-item Short Form awareness subscale (HypoA-Q SF) , was developed to identify IAH and characterize problematic hypoglycemia. We aimed to evaluate HypoA-Q SF’s concurrent and convergent validity.
Methods: Adults with T1D (n=23, 48% male; median age: 36 years, disease duration: 21 years) completed the (a) HypoA-Q SF, (b) Clarke score and (c) hypoglycemia severity (HYPO) score. Those with IAH defined by Clarke score ≥4 (n=12) and HYPO score ≥90th% were established on hybrid-closed loop insulin delivery as part of an ongoing 18-month clinical trial with 6-monthly completion of HypoA-Q, Clarke and HYPO scores. Mann-Whitney U Test was used to evaluate the HypoA-Q SF’s ability to differentiate between those with and without IAH. Repeated measures correlation was used to assess concordance between HypoA-Q SF score and Clarke / HYPO scores over the 18-month period.
Results: At baseline, HypoA-Q SF demonstrated concurrent validity as scores were significantly different between those with and without IAH (W= 110.5, p < .001) . Over the trial, HypoAQ-SF demonstrated convergent validity as repeated measures correlation analysis revealed significant positive relationships with both Clarke (r = 0.62 p < .001) and HYPO (r = 0.48, p<.01) scores.
Conclusion: These findings support the HypoA-Q SF as a tool to identify IAH and evaluate hypoglycemia severity. Further assessment of the HypoA-Q SF alongside gold-standard clamp-derived measures of autonomic symptom and counterregulatory response to hypoglycemia would be of value to determine score thresholds.
A.M.Matus: None. A.Flatt: None. A.J.Peleckis: None. C.V.Dalton-bakes: None. B.Riegel: None. M.R.Rickels: Advisory Panel; Sernova, Corp., Vertex Pharmaceuticals Incorporated, Zealand Pharma A/S, Consultant; L-Nutra Inc.
National Institutes of Health (R01DK091331; UL1 TR001878; P30 DK19525)