Beyond body mass index: visceral adiposity and metabolic alterations as early markers of atrial dysfunction and atrial fibrillation in midlife.

BACKGROUND

Atrial fibrillation (AF) develops along the cardiometabolic continuum, where visceral adiposity and early atrial dysfunction may precede overt disease. We aimed to identify independent predictors of new- onset and recurrent AF in middle-aged individuals with cardiometabolic risk.

METHODS

This observational cohort included 240 outpatients (40-60 years; 71 controls, 77 new-onset AF, 92 recurrent AF). Conventional anthropometric parameters (body mass index, body roundness index) and biochemical markers (fasting glucose, uric acid, creatinine clearance, inflammatory markers and high-sensitivity troponin I- hsTnI) were assessed. A comprehensive echocardiographic assessment including left atrial reservoir strain (LASr), electromechanical delay (EMD), and epicardial adipose tissue (EAT) were analyzed. Binary logistic regression and ROC analyses were performed.

RESULTS

New-onset AF was independently associated with fasting glucose (OR 3.604; 95% CI 1.338-9.704; p=0.011), EAT thickness (OR 1.479; p=0.006), electromechanical delay (OR 1.043; p=0.001), uric acid (OR 1.006; p=0.026), and lower LASr (OR 0.944; p=0.045). Among the evaluated parameters, EAT demonstrated the highest discriminatory ability for new-onset AF (AUC 0.664; p<0.001). Recurrent AF was independently associated with age (OR 1.122; p<0.001), BMI (OR 1.209; p=0.028), hsTnI (OR 3.546; p<0.001), and lower LASr (OR 0.845; p<0.001). LASr showed good discriminatory performance for recurrent AF (AUC 0.781; p<0.001).

CONCLUSION

These findings demonstrate that visceral adiposity and metabolic alterations are independently associated with atrial dysfunction and atrial fibrillation in middle-aged individuals with cardiometabolic risk.