Patients With Diabetes Requiring ED Care for Hypoglycemia
Patients With Diabetes Requiring ED Care for Hypoglycemia
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, 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.
Hypoglycaemia is the most feared complication of diabetes drug treatments and the most common diabetic emergency requiring emergency medical services. Its frequency in the community appears to be on the increase as well as its associated adverse outcomes. Hypoglycaemia is classified as mild if the episode is self-treated and severe if assistance by a third party is required. In patients with diabetes, because of their higher threshold for symptoms, often related to rate of fall in blood glucose, it is recommended that values of <4.0 mmol/L be treated. In patients with diabetes, hypoglycaemia can be caused by a variety of circumstances, including change in behavioural pattern, psychological issues and changes in the dose of hypoglycaemic therapies; it is almost exclusively related to insulin and sulfonylurea therapies. The patients at greatest risk are those in whom intensive glycaemic control is targeted.
Recently, three seminal studies—Action to Control Cardiovascular Risk in Diabetes (ACCORD), Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation and Veterans Affairs Diabetes Trial—did not show any benefit of intensive glycaemic control over standard control on cardiovascular events in patients with type 2 diabetes. These studies have significantly influenced guidance to clinicians and patients on glycaemic management. Thus, the National Institute for Health and Care Excellence (NICE) recommends an HbA1c of target of 6.5% in type 2 diabetes and 7.5% in others such as those on third-line therapies, those with multiple comorbidities and those with a long duration of diabetes. The quality and outcomes framework (QOF) introduced in the UK in 2004 recommended a target of ≤7% (53 mmol/mol) but has recently raised this to ≤7.5% (58 mmol/mol), largely in response to the ACCORD study. It is widely viewed that QOF and NICE guidance have improved diabetes care. However, it can be argued that setting generalised HbA1c targets can lead to intensification of glycaemic control in patients in whom this may not only be inappropriate but can also result in dangerous hypoglycaemia, particularly in the frail and elderly patients with multiple comorbidities.
A number of reports have demonstrated the burden and cost of hypoglycaemia requiring emergency services to the National Health Service (NHS) in the UK. Farmer et al estimated that in England alone the annual cost of emergency calls for hypoglycaemia was £13.6 million. Most of these reports rely on data from ambulance records only, underestimating the burden and cost of hypoglycaemia. Sulfonylurea-induced hospitalisation in the elderly is now increasingly recognised as a problem worldwide. A recent population-based study from a single county in the USA demonstrated significant long-term mortality in patients with type 2 diabetes who required emergency medical services for hypoglycaemia. Similar long-term mortality data are lacking in the UK. The aims of this study were to (1) triangulate three different data sources to accurately identify the number of patients with diabetes requiring emergency department (ED) care for hypoglycaemia in a defined UK population, (2) report the characteristics of patients with type 1 vs type 2 diabetes requiring ED care for hypoglycaemia and the characteristics of those on sulfonylureas versus those on insulin therapy and (3) report the long-term outcomes of all patients with diabetes requiring ED care for hypoglycaemia.
Abstract and Introduction
Abstract
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, 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.
Introduction
Hypoglycaemia is the most feared complication of diabetes drug treatments and the most common diabetic emergency requiring emergency medical services. Its frequency in the community appears to be on the increase as well as its associated adverse outcomes. Hypoglycaemia is classified as mild if the episode is self-treated and severe if assistance by a third party is required. In patients with diabetes, because of their higher threshold for symptoms, often related to rate of fall in blood glucose, it is recommended that values of <4.0 mmol/L be treated. In patients with diabetes, hypoglycaemia can be caused by a variety of circumstances, including change in behavioural pattern, psychological issues and changes in the dose of hypoglycaemic therapies; it is almost exclusively related to insulin and sulfonylurea therapies. The patients at greatest risk are those in whom intensive glycaemic control is targeted.
Recently, three seminal studies—Action to Control Cardiovascular Risk in Diabetes (ACCORD), Action in Diabetes and Vascular Disease: Preterax and Diamicron MR Controlled Evaluation and Veterans Affairs Diabetes Trial—did not show any benefit of intensive glycaemic control over standard control on cardiovascular events in patients with type 2 diabetes. These studies have significantly influenced guidance to clinicians and patients on glycaemic management. Thus, the National Institute for Health and Care Excellence (NICE) recommends an HbA1c of target of 6.5% in type 2 diabetes and 7.5% in others such as those on third-line therapies, those with multiple comorbidities and those with a long duration of diabetes. The quality and outcomes framework (QOF) introduced in the UK in 2004 recommended a target of ≤7% (53 mmol/mol) but has recently raised this to ≤7.5% (58 mmol/mol), largely in response to the ACCORD study. It is widely viewed that QOF and NICE guidance have improved diabetes care. However, it can be argued that setting generalised HbA1c targets can lead to intensification of glycaemic control in patients in whom this may not only be inappropriate but can also result in dangerous hypoglycaemia, particularly in the frail and elderly patients with multiple comorbidities.
A number of reports have demonstrated the burden and cost of hypoglycaemia requiring emergency services to the National Health Service (NHS) in the UK. Farmer et al estimated that in England alone the annual cost of emergency calls for hypoglycaemia was £13.6 million. Most of these reports rely on data from ambulance records only, underestimating the burden and cost of hypoglycaemia. Sulfonylurea-induced hospitalisation in the elderly is now increasingly recognised as a problem worldwide. A recent population-based study from a single county in the USA demonstrated significant long-term mortality in patients with type 2 diabetes who required emergency medical services for hypoglycaemia. Similar long-term mortality data are lacking in the UK. The aims of this study were to (1) triangulate three different data sources to accurately identify the number of patients with diabetes requiring emergency department (ED) care for hypoglycaemia in a defined UK population, (2) report the characteristics of patients with type 1 vs type 2 diabetes requiring ED care for hypoglycaemia and the characteristics of those on sulfonylureas versus those on insulin therapy and (3) report the long-term outcomes of all patients with diabetes requiring ED care for hypoglycaemia.
