Ethnic variations in the incidence of hypoglycaemia among people with type 2 diabetes prescribed insulins and/or sulphonylureas: a historical cohort study using general practice-recorded data.
Problem
Previous research in hospital settings has shown that severe hypoglycaemia varies between people of different ethnicities with diabetes. This study aims to identify any inter- and intra-ethnic group disparities in the risks of hypoglycaemia among people with type 2 diabetes prescribed insulins and/or sulphonylureas in community settings.
Approach
Using historical routine GP-recorded data, two cohorts of adults with type 2 diabetes in three east London boroughs were studied between January 2013 and December 2015: those prescribed (1) insulins with or without other oral antidiabetic medications (n=7,387); or (2) sulphonylureas with or without other oral antidiabetic medications excluding insulin (n=12,893). The primary outcome was clinically-recorded hypoglycaemia. Hazard ratios (HR) adjusting for age, sex, socioeconomic status and HbA1c were estimated using Cox regression.
Findings
After adjustment for age, sex, socioeconomic status and glycaemic control, Black African/Caribbean participants were at increased hypoglycaemic risk in both the insulin and sulphonylurea cohorts, HR 1.43 (95% CI, 1.18—1.73) and 1.68 (95% CI, 1.35—2.09) respectively compared to White subjects. South Asians were at significantly increased risk in the sulphonylurea cohort only, HR 1.28 (95% CI, 1.04—1.57). Indian, Pakistani and Other Asians in the insulin cohort were at increased risk of hypoglycaemia compared to Bangladeshis (p<0.001 for each): HR 1.95 (95% CI, 1.42—2.68), 1.99 (95% CI, 1.39—2.86) and 2.54 (95% CI, 1.67—3.85) respectively.
Consequences
Disparities in hypoglycaemic risk among people with type 2 diabetes prescribed insulin and/or sulphonylureas suggest important differences in biological and cultural responses to antidiabetic therapy between major ethnic groups. Such disparities warrant further study but should be considered by clinicians evaluating the treatment goals of their patients with type 2 diabetes using insulins or sulphonylureas.