High prevalence of previously unknown heart failure and left ventricular dysfunction in patients with type 2 diabetes.

The aim of this study was to assess the prevalence of (unknown) heart failure and left ventricular dysfunction in older patients with type 2 diabetes. In total, 605 patients aged 60 years or over with type 2 diabetes in the south west of the Netherlands participated in this cross-sectional study (response rate 48.7%), including 24 with a cardiologist-confirmed diagnosis of heart failure. Between February 2009 and March 2010, the patients without known heart failure underwent a standardised diagnostic work-up, including medical history, physical examination, ECG and echocardiography. An expert panel used the criteria of the European Society of Cardiology to diagnose heart failure. Of the 581 patients studied, 161 (27.7%; 95% CI 24.1%, 31.4%) were found to have previously unknown heart failure: 28 (4.8%; 95% CI 3.1%, 6.6%) with reduced ejection fraction, and 133 (22.9%; 95% CI 19.5%, 26.3%) with preserved ejection fraction. The prevalence of heart failure increased steeply with age. Heart failure with preserved ejection fraction was more common in women. Left ventricular dysfunction was diagnosed in 150 patients (25.8%; 95% CI 22.3%, 29.4%); 146 (25.1%; 95% CI 21.6%, 28.7%) had diastolic dysfunction. This is the first epidemiological study that provides exact prevalence estimates of (previously unknown) heart failure and left ventricular dysfunction in a representative sample of patients with type 2 diabetes. Previously unknown heart failure and left ventricular dysfunction are highly prevalent. Physicians should pay special attention to 'unmasking' these patients.