High Incidence of Hypoglycemia from an Audit of Glycemic Control and Management in Patients with Diabetes in a Cardiac Unit

INTRODUCTION The coronary care unit (CCU) model of care has evolved considerably over the past several decades and emerged as one of the most important advances in the care of patients with acute coronary syndrome (ACS). The concept of a specific unit for patients with ACS equipped with highly trained and specialized staff was initially introduced in the 1960s, but it was not until 1980s that the idea took off with the advent of coronary angiography and fibrinolytic therapy (1). However, in this new modern environment with high rate of cardiac interventions and patient turnover, many challenges have been created with competing demands for nursing time. These challenges are even greater in patients with diabetes frequently who require rapid intensification of therapy to optimize blood glucose levels whilst needing procedures which require fasting. The prevalence of diabetes in hospitalized patients is significant and is on an increasing trend. However, this figure is not well documented and hence significantly underestimated (2, 3). More than a decade ago, 12.4% of hospital discharges in the United States have diabetes documented as a diagnosis (4). More recently, the prevalence of diabetes was recorded from at least 10% and up to 25% of adult patients admitted to hospitals in the United Kingdom (5). Not surprisingly, this figure is increased in high-risk groups, particularly, patients admitted to a CCU. A 11years review of patients admitted to a CCU in Italy found a prevalence of diabetes at 31.5% and almost 40% with concomitant ST-elevation myocardial infarction (6). The combination of the busy modern CCU environment and the high and increasing number of patients with diabetes creates a high-risk setting for hypoglycemia. Severe hypoglycemia is known to be associated with increased morbidity and mortality in hospitalized patients and has been postulated to be associated to a range of adverse clinical outcomes or at least a marker of vulnerability to such events (7). This finding has been extended to patients hospitalized with ACS, where severe hypoglycemia was a major predictor of cardiovascular death (8). Similarly, hypoglycemia has also been implicated in the excess allcause mortality observed in this patient group (9).