Objective: Hypoglycaemia is thought to occur commonly in elderly patients with Type 2 diabetes in the hospital setting. The aim of this study was to investigate the incidence of and factors associated with hypoglycaemia in elderly patients with established type 2 diabetes (T2DM) admitted to a subacute hospital setting for rehabilitation.

Methods: A prospective study of all patients (aged >65 years) with T2DM admitted to a 200 bed, subacute rehabilitation hospital between December 2015 and February 2016. Hypoglycaemia was defined as a capillary blood glucose of <3.5mmol/L, with or without symptoms and leading to a medical emergency team (MET) call. After management of the MET call, the responding team leader was requested to complete a structured questionnaire. Factors associated with mortality were assessed using logistic regression.

Results: A total of 172 patients with known T2DM were admitted over the 3 month period. Seventeen (10%) had a MET call for a total of 27 episodes of hypoglycaemia, with 7 (41%) experiencing more than 1 episode. Only 22% of those with hypoglycaemia were reported as symptomatic, with the majority asymptomatic and detected at the time of routine testing. Patients experiencing hypoglycaemia were younger (75.+/-5.6 vs 80 +/-6.9, mean +/-SD, p 0.004), had a higher age adjusted Charlston co-morbidity index (7.5+/-2.7 vs 6.1+/-2.3, mean +/-SD, p 0.03) and were more likely to be on insulin (82% vs 23%, p <0.001). The most common antecedent factors for hypoglycaemia were inadequate food consumption (67%) and changes in nasogastric feeding regimens (11%).

All cause mortality was higher in patients who experienced hypoglycaemia than patients who did not (23.5% vs 7.1%, p 0.023).

Conclusions: Experience of in hospital hypoglycaemia in the subacute setting is common and identifies a highly vulnerable group of elderly patients who may benefit from strategies for improved nutrition and review of therapies.