New onset left atrial dilatation in the general population: A quarter-century follow-up

Background Information on the incidence of left atrial enlargement (LAE) and the factors underlying progressive LA remodelling in long-term longitudinal population-based studies is scanty. We investigated the incidence of new onset LAE and its determinants among middle aged adults over a 25-year time period. Methods A total of 423 participants with measurable echocardiographic parameters at baseline (mean age 41+10 years, 52 % men) and after a 25-year follow-up were included in the analysis. LA diameter (LAD) was measured with 2D-guided M-mode technique. LAE was detected according to sex-specific non-indexed criteria and a sex-independent indexed to body surface area (BSA) criterion recommended by contemporary echocardiographic guidelines. Results New LAE occurred in 27.4 % (absolute LA diameter, LAD) and 16.5 % (LAD/BSA), respectively. Initial LAD and body mass index (BMI), as well as the 25-year change in BMI and left ventricular mass index (LVMI) were independently correlated to incident non-indexed LAE. Besides age, the independent modifiable predictors of new-onset LAE/BSA were initial LAD/BSA, the 25-year change in BMI and 24-h pulse pressure (PP). Conclusions The incidence of LAE from mid to late adulthood occurs in a large clinically relevant fraction of participants and is affected by initial LAD, BMI and 25-year change in BMI, LVMI and 24-h PP. The findings provided by the present study support the view that avoid obesity and maintain normal levels of BMI, blood pressure and LVMI during life can contribute to strengthen cardiovascular prevention in the general population through prevention of LA remodelling and its harmful consequences.