Factors Associated with New-Onset Atrial Fibrillation in Thai Adults with Hypertension.

Background: Data on risk factors for new-onset atrial fibrillation (NOAF) in hypertensive Asian populations are limited. This study aimed to identify predictors of NOAF in Thai adults with hypertension (HTN).

Methods: We conducted a retrospective cohort study of adults (≥18 years) newly diagnosed with HTN at Ramathibodi Hospital, Bangkok, from 2010 to 2023. Patients with prior AF or predisposing conditions (e.g., valvular disease, hyperthyroidism) were excluded. Baseline demographics, comorbidities, and medication use were analyzed as time-varying covariates using multivariable Cox models.

Results: Of 293,798 hypertensive patients, 168,441 met the criteria. Over a median follow-up of 3.7 years, 5,028 developed NOAF (5.7 per 1,000 person-years). A significant interaction between age and body mass index (BMI) was observed. In patients <60 years, low BMI increased NOAF risk (HR: 2.3; 95% CI: 1.4-3.6), while overweight and obesity did not. In those ≥60-79 years, NOAF risk increased 2- to 3-fold in underweight, overweight, and obese individuals compared to normal BMI. In patients ≥80 years, the risk was 3- to 4-fold higher across all BMI categories. Male sex and comorbidities (vascular disease, stroke, heart failure, chronic kidney disease, hyperuricemia) were associated with a 1.2-1.8-fold increased risk. Statin use reduced NOAF risk (HR: 0.8; 95% CI: 0.7-0.9), while SGLT2 inhibitors and GLP-1 receptor agonists showed a non-significant protective trend (HR: 0.8; 95% CI: 0.7-1.1).

Conclusions: In Thai hypertensive patients, older age, male sex, abnormal BMI, and comorbidities predict NOAF, while statin use may be protective. Further prospective studies are needed to confirm these findings.