Differential associations of risk factors with severe and nonsevere hypoglycaemia: HAT prospective observational study in people with insulin-treated type 1 and type 2 diabetes

AIMS: Severe and non-severe hypoglycaemia are closely related conditions but the extent to which they share risk factors is uncertain. We aimed to assess the differential association of risk factors with severe and non-severe hypoglycaemia.

MATERIALS AND METHODS: The HAT study evaluated the risk of hypoglycaemia over a 4-week period in patients with type 1 (T1D) and 2 diabetes (T2D) on insulin in 24 countries. Negative binomial regressions were applied to examine associations of several risk factors with severe and non-severe hypoglycaemia.

RESULTS: Median age was 41 years in 5,949 patients with T1D and 62 in 12,914 with T2D. The 4-week rates of non-severe hypoglycaemic were 5.57 and 1.40 episodes per person in T1D and T2D, respectively; corresponding rates for severe hypoglycaemia were 0.94 and 0.30. The excess risk was 42% higher for severe than non-severe hypoglycaemia in females vs males with T2D; 27% higher, in patients with T2D with vs without continuous glucose monitor (CGM); and 47% lower, in patients with T1D with vs without insulin pump. The excess risk also differed across geographical areas and was marginally lower for severe than non-severe hypoglycaemia for higher values of HbA1c in patients T2D. Associations with severity of hypoglycaemia were not different for age, diabetes and insulin therapy duration, previous hypoglycaemic episodes, and insulin regimen. 

CONCLUSIONS: The risk of severe versus non-severe hypoglycaemia differs in patients with T1D and T2D, with sex, use of CGM and insulin pump, and geographical areas differently associated with one type of hypoglycaemia than the other.