Cardiac and vascular characteristics and gender-related modifications induced by ageing in the founder population of SardiNIA project (ProgeNIA)

Background.Cardiovascular diseases are the leading cause of death and disability in Western countries and this is expected to worsen as the population is aging. Aging induces structural and functional changes in the heart and vessels which increase the likelihood of cardiovascular events. Little data is available about gender-related and population-related differences in cardiovascular adaptation to aging. In 2001 the SardiNIA (ProgeNIA) project began in Sardinia. It’s brief was to identify the genetic determinants of complex traits associated with aging in 6148 volunteers with documented Sardinian parentage, enrolled in four villages in the Ogliastra province. In 2013 echocardiography was introduced to investigate the structural and functional cardiac traits.Aim.1) To describe the clinical and echocardiographic characteristics of a large sample of the SardiNIA cohort; 2) To assess the normal values of the echocardiographic parameters and the best method of their indexation for body size (height, weight, body mass index, body surface area), in a sample free of cardiovascular diseases; 3) To investigate the effects of ageing on the heart and aorta and the gender-specific differences.Methods.Of the original 6148 SardiNIA volunteers, 3131 subjetcs underwent a transthoracic echocardiogram according to a standardized protocol and were enrolled in this study. Complete clinical and laboratory data and good quality 2D and M-mode echocardiographic images were available in 2926 of them (47.6% of the whole SardiNIA cohort). All the echocardiographic images were analyzed by a single expert cardiologist. The following parameters were measured: end-diastolic left ventricular (LV) internal diameter (EDD) and volume (EDV), interventricular septum, posterior wall thickness, LV mass (LVM), ejection fraction (EF), stroke volume (SV), transmitral early (E) and atrial (A) flow velocity and their ratio (E/A), left atrial diameter (LAD) and volume (LAV), aortic root and ascending aorta dimensions. According to clinical and laboratory data, office blood pressure, ABPM, ECG and echocardiography, 1977 subjects (62% women) were free of diabetes and apparent cardiovascular disease and were considered normal.Results.The prevalence of some cardiovascular risk factors in the SardiNIA sample group was quite low, probably due to the relatively young mean age of the sample, but genetic and environmental factors may also play a role. Gender-specific normal reference values of the major echocardiographic parameters were obtained, after normalizing for body surface area (BSA). In the Sardinian population ageing is associated with significant left ventricular remodelling, left atrial enlargement and diastolic dysfunction, while systolic function is preserved. It is noteworthy that all these changes are quantitatively more pronounced in women.Discussion.This study provides normal reference values of the echocardiographic indices, specific for the Sardinian population. The best method of their indexation resulted in being the isometric scaling using BSA, whereas the allometric methods of normalizing LVM (LVM/height2.7 and LVM/height1.7) overestimated LVM in the smallest subjects (mostly women) of the Sardinian population, with potential distorsive effect in estimating the true prevalence of LV hypertrophy. This data suggests that the best methods of indexing LVM for body size depend on the anthropometric characteristics of the study population. In the Sardinian population, ageing is associated with significant left ventricular remodelling, left atrial enlargement, aortic dilatation and diastolic dysfunction, while systolic function is preserved. It is worth noting that all these changes are more pronounced in women.