Heart failure in community-dwelling older persons: Aims, design and adherence rate of the ICARe Dicomano project: An epidemiologic study

BACKGROUND: The prevalence of heart failure (HF) increases with age, and HF is a major cause of disability and mortality in older persons. Detection of HF in epidemiological studies has relied on criteria validated only in young and middle-age adults, and, therefore, may prove inadequate in older subjects, because they do not take into account the pathophysiologic and clinical peculiarities of HF in old age. Thus? the true prevalence of HF in the older general population remains uncertain and has probably been underestimated in previous studies. Moreover, the mechanism and the extent by which HF hinders physical functioning in older people has not been fully elucidated. OBJECTIVES: This paper describes the design of the ICARe study, carried out in an older home-dwelling population to collect data about: (1) the sensitivity and specificity of diagnostic criteria used previously in epidemiological studies of HF; (2) the prevalence of the different pathophysiologic forms of HF; and (3) the impact of HF on overall health status, and on physical functioning, in the absence or presence of chronic comorbidity. DESIGN AND SETTING: This was a cross-sectional survey. Eligible were all community-dwelling persons aged 65 years or older recorded in the Registry Office of Dicomano, a small town nearby Florence (Italy). All the domains of multidimensional geriatric assessment were explored through different phases of the study (home interview, laboratory testing, geriatric visit) that comprised an extensive cardiopulmonary instrumental assessment including: color Doppler echocardiography, echotomography of the carotid arteries used in an original method to determine arterial compliance, and bell spirometry. Presence of major chronic conditions was ascertained by predefined, standard algorithms that were based largely on clinical examination. RESULTS: There were 864 older persons eligible for the ICARe study. Even with a substantial decline from home interview (91.2%) to the cardiopulmonary study (71.1%), the adherence rate remained high throughout the study, and the population examined was fairly representative of the original eligible population. Thus, we believe that the data collected in this study offer a unique opportunity to assess the validity of the diagnostic clinical criteria for HF in the general older population, to identify the pathophysiology underlying the syndrome, and to investigate the relationship between HF, comorbidity, and disability.