Prevalence of impaired awareness of hypoglycaemia and frequency of hypoglycaemia in insulin-treated type 2 diabetes

The present study sought to ascertain the prevalence of impaired awareness of hypoglycaemia (IAH) in people with insulin-treated Type 2 diabetes (T2DM) and its effect on risk of hypoglycaemia. Data were obtained from 122 people with insulin-treated T2DM (63 male; mean (SD) HbA1c 8.4% (1.5); median (inter quartile range, IQR) age, 67 (58-72) years; duration of T2DM 15 (10-20) years; duration of insulin therapy, 6 (4-9) years). A questionnaire was used to evaluate hypoglycaemia awareness status and estimate the frequency of severe hypoglycaemia (SH) in the preceding year. Capillary blood glucose was monitored prospectively over a 4-week period to document biochemical hypoglycaemia. The prevalence of IAH was 9.8%. In the subgroup with IAH the incidence of SH in the preceding year was 17-fold higher than those with normal hypoglycaemia awareness (0.83 (1.12) vs. 0.05 (0.28) episodes per patient; p <0.001 (n=122)) and had a five-fold higher incidence of biochemical hypoglycaemia (2.43 (4.39) vs. 0.46 (1.21) episodes; p <0.001 (n=63)). The prevalence of IAH in insulin-treated T2DM was associated with higher frequencies of SH and biochemical hypoglycaemia. Therefore the presence of IAH in those with insulin-treated T2DM should be evaluated at clinical review