Effect of fitness on cardiac structure and function in overweight and obesity (the FATCOR study).
Obesity is associated with reduced left ventricular (LV) systolic myocardial function. We aimed to explore by means of a cross-sectional study whether this effect is offset in the presence of good fitness. We studied clinical and echocardiographic data from 469 overweight (body mass index [BMI] >27 kg/m2) and obese (BMI ≥30 kg/m2) women and men without known cardiovascular (CV) disease in the FAT associated CardiOvasculaR dysfunction (FATCOR) study. The participants were grouped according to obesity and sex- and age adjusted peak oxygen uptake, obtained by ergospirometry. LV systolic myocardial function was assessed by peak systolic global longitudinal strain (GLS) measured by speckle tracking echocardiography. The association of fitness with GLS was tested in logistic regression analyses and reported as odds ratio (OR) with 95% confidence interval (CI). In the total study population, participants were 47 years old, 60% were women, and mean BMI was 32.0 kg/m2. GLS did not differ between fit and unfit subjects within the overweight and obese groups (both p > 0.05), but the overweight fit group had higher GLS (more negative value) compared to the obese unfit group (-20.1 ± 2.6 vs. -19.0 ± 3.0, p < 0.05). In obese subjects, fitness was associated with higher GLS (OR 0.88 [95% CI 0.79-0.99, p < 0.05) in multivariable logistic regression analysis, independent of significant associations with higher arterial stiffness and lower fat percentage (all p < 0.05). In the overweight group, fitness was not significantly associated with GLS. In obesity, fitness was independently associated with higher GLS, while no association was found in overweight. URL: http://www.clinicaltrials.govNCT02805478.