The impact of longitudinal changes in BMI and serum uric acid levels on new-onset atrial fibrillation

Abstract

Abstract Background The worldwide prevalence of atrial fibrillation (AF) is already estimated at 33 million and it is still increasing. In order to prevent the increase in the prevalence of AF, it is important to understand the risk of developing AF and to take preventive intervention. Obesity and serum uric acid level (UA) are both associated with the incidence of AF. However, it is unclear about synergistic effect of longitudinal changes in both BMI and UA on the new-onset AF. We assessed the impact of longitudinal changes in BMI and UA on the subsequent incidence of new-onset of AF. We also estimate the number of new-onset AF that could be prevented by maintaining BMI and UA. Methods We retrospectively analyzed 17,994 Japanese without a history of AF from a cohort of employees undergoing annual health examinations conducted between April 2013 and April 2022. Exclusion criteria included missing laboratory values, three or fewer visits, developed AF by Visit 3, Visit 1 to 3 was less than 1.5 years or more than 4 years, medication for hyperuricemia, and renal dysfunction (serum Cre≥1.2 mg/dL in men and 1.0 mg/dL in women). Result During a follow-up period of 3.77 years, the incidence of AF was 70 (1.04/1,000 person-years). A multivariable Cox regression analysis showed that the new-onset AF was associated with age, gender, weight gain, UA at baseline and increased UA. A multivariable Cox regression analysis with interaction term between weight gain (≥10 kg weight gain since age 20) and increased UA (1 mg/dl) showed that significant increased risk for new-onset AF were age (HR: 3.15, [95%CI; 2.44-4.06], P<0.001), gender (HR: 0.41, [95%CI; 0.20-0.84], P=0.016), weight gain (HR: 1.46, [95%CI; 1.16-1.84], P=0.001), systolic blood pressure at baseline (HR: 1.01, [95%CI; 1.00-1.03], P=0.048), UA at baseline (HR: 1.29, [95%CI; 1.02-1.63], P=0.036), and interaction term (HR:1.93, [95%CI; 1.36-2,72], p for interaction=0.006). Using the prediction model for developing AF including the interaction term, we estimated the number of new-onset AF in Japanese male aged 40-69 years in the next 5 years. An increase in uric acid of 1 mg/dL and BMI of 2 units over the past two years was predicted to result in approximately 460 000 new cases of AF/5 years, but it was estimated that maintaining uric acid levels and BMI could reduce the number of cases by 75% (preventing 344 000 new cases of AF/5 years). Conclusion Weight gain and increased uric acid had a synergistic effect on the risk of developing AF. Particularly in men, maintaining serum uric acid levels in those who gained weight (≥10 kg weight gain since age 20) was found to prevent 75% of new-onset of AF over a five-year period, based on our modelling analysis.Multivariable Cox Regression AnalysisEstimated number of AF incidents