Patients with diabetes requiring emergency department care for hypoglycaemia: characteristics and long-term outcomes determined from multiple data sources.

Aim: To triangulate three data sources and report the characteristics and long-term outcomes of patients with diabetes requiring emergency department (ED) care for hypoglycaemia.

Method: Three data sources were used-ambulance electronic records, hospital episode statistics and patient administration system. Hypoglycaemia (capillary blood glucose <4.0 mmol/L)-related attendances to a single hospital's ED between 1 April 2012 and 31 March 2013 were studied.

Results: Using the three sources, there were 165 hypoglycaemia-related attendances in 132 patients with diabetes [type 1-59 episodes in 43 patients, type 2-106 episodes in 89 patients (therapy-54 (51%) insulin, 35 (33%) sulfonylurea, 11 (10%) both, 6 (6%) others)]. At best only 65% of episodes would have been identified were a single data source used. Patients with type 2 vs type 1 diabetes were older (median age 79 vs 61 years, p<0.0001), had more comorbidities (median Charlson comorbidity index (CCI) 4 vs 3, p=0.002) but no difference in HbA1c (median 7.8% vs 8.4%, p=0.065). Compared with insulin-treated type 2 patients with diabetes, sulfonylurea-treated patients (33%) were older (median age 82 vs 76 years, p=0.007), had worse renal function (median estimated glomerular filtration rate 38 vs 56 mL/min/1.73 m(2), p=0.019) and lower HbA1c (median 6.7% vs 8.4%, p<0.0001). At least 17 (10%) hypoglycaemic episodes resulted in additional serious harm. The 30-day, 90-day and 1-year all-cause mortality were 10.6% (14), 16.7% (22) and 28% (37), respectively. Age, CCI and hospitalisation were risk factors for long-term mortality.

Conclusions: Dependence on a single data source would have at best identified only 65% of episodes. One-third of episodes were sulfonylurea related in patients with type 2 diabetes, and one-fourth of all patients with diabetes who required ED care for hypoglycaemia died the following year.