A large-scale study led by British Heart Foundation funded researchers at NDPH and published in the International Journal of Epidemiology has demonstrated that higher lean mass, fat mass, and waist circumference are each independently associated with higher risks of atrial fibrillation (a common cardiac arrhythmia that increases risk of stroke).
Although the harmful effect of body mass index on risk of atrial fibrillation is well established the relative importance of different measures of body composition, as well as their relevance in men and women, has remained unclear.
The researchers analysed data from the UK Biobank including 477,904 participants of whom 23,134 developed atrial fibrillation over 11 years of follow-up. The study demonstrated that for every 5kg greater lean mass, women had a 40% higher risk of atrial fibrillation while men had a 24% higher risk. In both men and women, a 5kg higher fat mass was associated with an 18% higher risk of atrial fibrillation, and a 10cm greater waist circumference associated with a 30% higher risk.
All three measures had independent effects on risk and, although comparisons of their relative effects identified different patterns within each sex, lean mass was the strongest predictor of atrial fibrillation in both men and women.
Dr Fielder Camm, British Heart Foundation Clinical Research Training Fellow in NDPH, and joint first author said: ‘These findings are important as they illustrate potential differences in the way body size affects the risk of atrial fibrillation in men and women. The identification of waist circumference as a risk factor for this common cardiac condition suggests that regional fat deposits may play a role in the development of this heart condition.’
Jemma Hopewell, Professor of Precision Medicine & Epidemiology in NDPH, British Heart Foundation IBSR Fellow, and joint senior author commented: ‘This study shows that there are multiple measures of body composition that each contribute important information about our risk of atrial fibrillation, and provides further evidence to support current public health messaging and weight-loss focused treatment initiatives.’