Comments on “Impaired awareness of hypoglycaemia in subjects with type 1 diabetes”

Sir,

We would like to congratulate I. Conget et al. on the results of their study on the impaired awareness of hypoglycemia (IAH) in patients with type 1 diabetes mellitus (T1DM),¹ where the authors report that approximately a quarter of patients with T1DM who completed an online survey had an abnormal perception of hypoglycemia. In order to ascertain whether our population with T1DM had an IAH rate as high as reported by these authors, in April 2016 we assessed the results in the Clarke test, validated in Spanish,² of 100 patients (57% males) with T1DM (mean age: 35.4 ± 12.8 years; time since TDM onset: 16.9 ± 11.6 years; mean HbA1c: 7.7 ± 1.1%) consecutively attending the monographic T1DM clinic who were on basal-bolus therapy (mean insulin dose: 0.76 ± 0.4 IU/kg/day). In this population, 25% were found to have an abnormal perception of hypoglycemia, 10% an indeterminate perception, and 65% a normal perception. These results are very similar to those reported by I. Conget et al.¹ and other authors.³ As compared to patients with normal perceptions, those with IAH were older (41.4 ± 13.8 vs 33.6 ± 12.2 years; p: 0.019), had a longer duration of diabetes (22.0 ± 13.3 vs 15.3 ± 10.7 years; p: 0.032), and had experienced a higher number of severe hypoglycemic episodes over the previous 6 months (1.0 ± 1.3 vs 0.15 ± 0.83; p < 0.001). No differences were seen, however, in the Clarke test score between the sexes or as a function of the current HbA1c level or the mean HbA1c level over the previous five years.

Hypoglycemia is possibly the greatest limiting factor for achieving optimum metabolic control in patients with T1DM.⁴ IAH in these patients represents a serious barrier to adequate disease control, impairs quality of life,⁵ and increases the risk of the development of severe hypoglycemia.^1,6 Strategies (such as completion of the Clarke test) should therefore be implemented to allow for the early identification of these patients in order to improve their diabetes education (adequate nutrition, adjustments with exercise, etc.), readjust their control goals (at least temporarily),⁶ and optimize their insulin therapy, in an attempt to improve their perception of and response to hypoglycemia and to decrease their risk of developing severe hypoglycemia in the future.