Altered fasting glycemia in cardiac patients during in-hospital rehabilitation: Impact on short and long-term follow-up

Background and aims: Hospitalized patients after acute cardiovascular events have poorer prognosis if glucose regulation is diagnosed as abnormal. We compared the short and long-term outcome of patients with newly diagnosed altered fasting glycemia (AFG) to that of known diabetic patients and patients with normal glucose regulation (NGR) after admission to cardiac rehabilitation. Methods: We retrospectively analyzed 2490 consecutive patients. Three groups were identified: known diabetes mellitus (n = 540, 22%), fasting glycemia above 110 mg/dl (AFG, n = 269, 11%), and fasting glycemia 110 mg/dl or less (NGR, n = 1681, 67%). Clinical variables, complications, and all-cause mortality were evaluated. Results: At follow-up (median 3.1 ± 2.4 years), after adjustment for age, sex, BMI, left ventricular ejection fraction, history of coronary artery disease, AFG had a significantly longer hospital stay versus NGR (21 ± 8 versus 20 ± 8 days; P = 0.019) and higher risk of paroxysmal atrial fibrillation (P = 0.041), pleural/pericardial effusions (P < 0.001), skin complications (P = 0.033), other events (P = 0.001), and blood tests (urea: P = 0.007; white blood cells: P = 0.002; neutrophils: P < 0.001; creatinine: P = 0.022). All-cause mortality was significantly higher in diabetes mellitus versus NGR (odds ratio 1.61, 95% confidence interval 1.17-2.21); a nonsignificant trend was observed in AFG versus NGR (odds ratio 1.23, 95% confidence interval 0.77-1.98). Conclusions: A high AFG prevalence in cardiac patients admitted to rehabilitation was observed. AFG patients were more vulnerable than NGR patients, had higher complication rates independently of covariates, and required longer hospital stay. AFG was not a significant predictor of all-cause mortality at 3 years, whereas DM was.