NEW YORK (Reuters Health) - In a prospective study of adult patients at Massachusetts General Hospital in Boston, nearly one in five had elevated glycosylated hemoglobin A (HbA1c) levels, indicative of probable unrecognized diabetes, investigators report in the November issue of the Journal of Clinical Endocrinology and Metabolism.
"Screening with HbA1c levels at the time of admission to an acute care hospital may represent an opportunity to identify a high-risk group of patients with unrecognized diabetes and, if coupled with effective follow-up, to promote prevention of subsequent diabetes-related complications," Dr. Deborah J. Wexler and associates conclude.
Their observational cohort study included 695 patients admitted during 11 days in the summer of 2006, of whom 136 (20%) had previously diagnosed diabetes.
A total of 123 (18%) patients had HbA1c levels > 6.1% with no diabetes diagnosis in their charts, a rate that is "roughly 5-fold higher than in the general outpatient population," the investigators report. Thirty-three patients (5%) had HbA1c levels > 6.5%.
Random glucose measurements showed that patients with undiagnosed probable diabetes were no more likely than nondiabetic patients to exhibit hyperglycemia.
"Random glucose levels, accordingly, were insensitive and nonspecific for the diagnosis of diabetes," Dr. Wexler's team maintains. The positive and negative predictive values of random glucose levels > 200 mg/dL for unrecognized probable diabetes were 52% and 87%, respectively.
Only 15% of surviving patients who were followed up within the hospital-affiliated healthcare system were diagnosed with diabetes during the subsequent year.
"Consequently," the researchers state, "the utility of diagnosis for inpatients is likely to be low unless patients subsequently receive long-term outpatient care to prevent complications of diabetes."
