Impact of diabetes and on-arrival hyperglycemia on short-term outcomes in acute heart failure patients

The impact of diabetes mellitus (DM) and hyperglycemia on short-term prognosis in patients with acute heart failure (AHF) remains controversial as most data comes from series of hospitalized patients. Our purpose was to analyze outcomes in a nation-wide registry of AHF patients attended in emergency department (ED). ED AHF patients were prospectively enrolled, with the index event and the vulnerable post-discharge phase outcomes recorded. The influence of presenting hyperglycemia (> 180 mg/dL) and DM treatment on prognosis were also investigated. All results were adjusted (a) for baseline characteristics. Of 9192 enrolled AHF patients, 4544 (49,4%) were diabetic, with 24% of diabetics and 25.1% of non-diabetic (p = 0.247) directly discharged from the ED also included. Diabetics had higher rates of comorbidities, but were slightly younger and had lower in-hospital and 30 day all-cause mortality than non-diabetics (a-OR = 0.827, 95% CI = 0.690–0980; and a-HR = 0.850, 95% CI = 0.814–1.071, respectively). Conversely, hyperglycemia on-arrival was associated with increased in-hospital, and 30 day all-cause mortality, in both DM (a-OR = 1.933, 95% CI = 1.378–2.712, and a-HR = 1.590, 95% CI = 1.304–1.938, respectively) and non-DM patients (a-OR = 1.498, 95% CI = 1.175–1.909, and a-HR = 1.719, 95% CI = 1.306–2.264, respectively). However, during the vulnerable phase, diabetics had worse short-term outcomes, with higher rates of ED-revisit and rehospitalization. These worse outcomes seemed to be unrelated to the severity of DM. In patients with AHF attended in ED, diabetes was associated with lower index event case fatality, but higher rates of rehospitalization and re-consultation in the vulnerable post-discharge period. Conversely, hyperglycemia at hospital arrival was strongly associated with early mortality, regardless of diabetes status.