National Trends in US Hospital Admissions for Hyperglycemia and Hypoglycemia Among Medicare Beneficiaries, 1999 to 2011

Abstract

Severe hypoglycemia is the most common acute adverse effect of glucose-lowering therapy among patients with diabetes mellitus (DM) and is associated with poor outcomes,^1-4 including death.^5-8 Several recent trials have raised questions about the benefits of intensive glucose control and have demonstrated harms associated with these strategies, including severe hypoglycemia^9-11 and even mortality.⁹ Older patients, particularly those with multiple comorbidities, may derive less benefit from intensive strategies to lower glucose levels¹² and may be more susceptible to hypoglycemia¹³ and its consequences. Despite these concerns for older patients, DM care quality metrics established more than a decade ago have primarily focused on prevention of hyperglycemia and its complications and rewarded target-based glucose lowering to achieve a hemoglobin A_1c (HbA_1c) level below 7% of total hemoglobin^14,15 and, more recently, below 8% of total hemoglobin.¹⁶ These efforts have been successful, and the proportion of patients with DM achieving HbA_1c levels below these thresholds improved significantly between 1999 and 2010.^17,18 However, the consequences of these changes may include increased rates of hypoglycemia. (To convert HbA_1c to a proportion of total hemoglobin, multiply by 0.01.)