Risk factors and outcome differences in hypoglycaemia-related hospital admissions A case-control study in England.

AIMS: To evaluate risk factors for hospital admissions for hypoglycaemia and compare length of hospitalisation, inpatient mortality, and hospital readmission between hypoglycaemia and non-hypoglycaemia-related admissions. MATERIALS AND METHODS: We used all admissions for hypoglycaemia in people with diabetes to English NHS hospital trusts between 2005 and 2014 (101,475 case admissions) and three random admissions per case in people with diabetes without hypoglycaemia (304,425 control admissions). Risk factors and differences in the three outcomes were estimated with logistic and negative binomial regressions. RESULTS: A U-shaped relationship between age and risk of admission for hypoglycaemia was observed until the age of 85 years: compared to the nadir at 60 years, the risk was progressively higher in younger and older patients and steadily declined after 85 years. Social deprivation (positively) and comorbidities (negatively) were associated with the risk of admission for hypoglycaemia. Compared to Caucasians, other ethnic groups had lower (Bangladeshi, Pakistani, Indians) or higher (Caribbean) risk of admission for hypoglycaemia. Length of hospitalisation was 26% shorter while risk of rehospitalisation was 65% higher in people admitted for hypoglycaemia. Compared to admissions for hypoglycaemia, risk of inpatient mortality was 50% lower for unstable angina but higher for acute myocardial infarction (3 times), acute renal failure (5), or pneumonia (8). CONCLUSIONS: Among hospital-admitted individuals with diabetes, age, social deprivation, comorbidities, and ethnicity are associated with higher frequency for hospitalisation due to hypoglycaemia. Admission for hypoglycaemia is associated with a greater risk of readmission, a shorter length of hospitalisation, and a generally lower inpatient mortality compared to admissions for other medical conditions. These results could help identifying at-risk groups to reduce the burden of hospitalisation for hypoglycaemia.