Clinical significance of impaired relaxation pattern in middle-aged and elderly adults in the general population

Introduction: The prevalence of diastolic dysfunction in the general population is largely unknown. The purpose of this study was to assess the prevalence of impaired relaxation pattern with normal ejection fraction (IRPNEF) in a population health survey and to analyze associated characteristics. Methods: This was a cross-sectional evaluation of 739 community participants aged 45 years or older, randomly selected from the general population. Subjects with left ventricular systolic dysfunction (ejection fraction <45%), moderate or severe valvular disease or restrictive pattern were excluded, resulting in 653 individuals (age 61.4 +/- 10.3 years, 60.8% women). Diastolic dysfunction was classified according to transmitral inflow pulsed Doppler data. Results: Overall, 215 (32.9%) had impaired relaxation. IRPNEF was associated with older age (p<0.001), arterial hypertension (p<0.001), diabetes (p=0.03), coronary artery disease (p=0.006) and metabolic syndrome (p=0.014). The echocardiographic characteristics associated with IRPNRF were LV hypertrophy (p<0.001) and left atrial diameter index (p=0.008). No relation was found between IRPNEF and the clinical syndrome of heart failure or increased BNP level. Nevertheless, exertion dyspnea was more prevalent among subjects with IRPNEF (p=0.004). In stratified analysis, arterial hypertension, metabolic syndrome and echocardiographic LV hypertrophy were associated with IRPNEF in subjects younger than 65 years, but not in the elderly. Among younger subjects, in multivariate logistic regression analysis, hypertension was a significant predictor of IRPNEF even when adjusting for LV hypertrophy (OR 2.23 [95% CI 1.33-3.73]). Conclusions: We found a high prevalence of IRPNEF in the general population, in most cases unaccompanied by overt heart failure. IRPNEF was associated with hypertension in younger subjects but not in the elderly, in agreement with the concept that in older subjects it represents a physiologic phenomenon. IRPNEF was not associated with neurohumoral activation.