A Comparison of Validated Methods Used to Assess Impaired Awareness of Hypoglycaemia in Type 1 Diabetes: An Observational Study

Kshitiz Ghandi; Beatrice Pieri; Anne Dornhorst; Sufyan Hussain

doi:10.1007/s13300-020-00965-0

A Comparison of Validated Methods Used to Assess Impaired Awareness of Hypoglycaemia in Type 1 Diabetes: An Observational Study

Diabetes Ther. 2021 Jan;12(1):441-451. doi: 10.1007/s13300-020-00965-0. Epub 2020 Nov 20.

Authors

Kshitiz Ghandi^{1

2}, Beatrice Pieri³, Anne Dornhorst^{1

2}, Sufyan Hussain^{4

5

6}

Affiliations

¹ Department of Diabetes, Endocrinology and Metabolism, Imperial College London, London, UK.
² Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, London, UK.
³ Department of Diabetes, School of Life Course Sciences, King's College London, London, UK.
⁴ Department of Diabetes, Endocrinology and Metabolism, Imperial College London, London, UK. Sufyan.hussain@kcl.ac.uk.
⁵ Department of Diabetes and Endocrinology, Imperial College Healthcare NHS Trust, London, UK. Sufyan.hussain@kcl.ac.uk.
⁶ Department of Diabetes, School of Life Course Sciences, King's College London, London, UK. Sufyan.hussain@kcl.ac.uk.

Abstract

Introduction: Clarke, Gold and Pedersen are validated methods to assess awareness of hypoglycaemia. Identifying impaired awareness of hypoglycaemia (IAH) is critical for supporting people with structured education and diabetes technologies, to reduce harm of hypoglycaemia. This study compares the Clarke score, Gold score and Pedersen methods and their correlations with features of hypoglycaemia unawareness and patient characteristics, to evaluate the accuracy of the methods in identifying IAH.

Methods: This retrospective, observational questionnaire-based study collected routine clinical data from 100 people with type 1 diabetes. The questionnaire included the three validated scoring methods, frequency of severe and nocturnal hypoglycaemia, knowledge and worry of hypoglycaemia and hypoglycaemia symptom scores using the Edinburgh Hypoglycaemia Scale. Data were analysed for IAH prevalence and the associations with features of IAH. The concordance of Clarke, Gold and Pedersen methods was evaluated using Spearman's correlation coefficient.

Results: The prevalence of IAH in this cohort identified by Clarke, Gold and Pedersen methods was 18%, 19% and 61% respectively. The mean autonomic symptom score in people with IAH was significantly reduced using the Clarke method (P = 0.0002) but not on Gold (P = 0.12) and Pedersen methods (P = 0.79). For people with IAH assessed using the Clarke method, scores for night-time worry regarding hypoglycaemia (P = 0.04) and self-reported frequency of nocturnal hypoglycaemia (P = 0.001) were increased. Spearman's correlation coefficients between Pedersen and Clarke and Pedersen and Gold were R_s = 0.555 (P < 0.001) and R_s = 0.645 (P < 0.001) respectively. A moderate association was observed between Clarke and Gold R_s = 0.5669 (P < 0.001).

Conclusion: Whilst Clarke and Gold methods determined a similar prevalence of IAH, people identified with IAH assessed by the Clarke method had a significant association with the features and characteristics of IAH, including reduced autonomic symptoms. This study suggests that performing more than one score is important for a reliable risk assessment of IAH.

Keywords: Hypoglycaemia; Hypoglycaemia unawareness; Impaired awareness of hypoglycaemia; Type 1 diabetes.