Incidence of hypoglycaemia among insulin-treated patients with type 1 or type 2 diabetes mellitus: South African cohort of International Operations Hypoglycaemia Assessment Tool (IO HAT) study

Objectives: To assess the incidence and rates of hypoglycaemia in patients with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) in the South African cohort of the International Operations Hypoglycaemia Assessment Tool (IO HAT) study. Methods: Patients diagnosed with either T1DM or T2DM, aged ≥ 18 years and treated with insulin for > 12 months, completed self-assessment questionnaires to record demography, treatment information and hypoglycaemia during a 6-month retrospective and 4-week prospective periods (ClinicalTrials.gov: NCT02306681). Results: In T1DM 76.2% (95% confidence interval [CI] 69.1%, 82.3%) of patients reported hypoglycaemia in the retrospective period and 98.2% (95% CI 94.7%, 99.6%) in the prospective period. The corresponding figures for patients with T2DM were 52.2% (95% CI 48.6%, 55.9%) and 90.1% (95% CI 87.7%, 92.3%), respectively. Rates of any and severe hypoglycaemia, respectively were T1DM 90.7 events per patient year (PPY) (95% CI 85.5, 96.1) and 8.8 events PPY (95% CI 7.2, 10.6) and T2DM 45.7 events PPY (95% CI 43.9, 47.5) and 8.9 events PPY (95% CI 8.1, 9.8) during the prospective period. The rates of hypoglycaemia were independent of glycated haemoglobin levels. Conclusions: This is the first patient dataset of self-reported hypoglycaemia in South Africa; results showed that hypoglycaemia is under-reported.