Half of AF cases preventable through better risk-factor control
MedWire News: The burden of atrial fibrillation (AF) could be halved through optimal control of cardiovascular (CV) risk factors, a US study suggests.
The study was based on more than 17 years of follow-up of 14,598 middle-aged participants in the Atherosclerosis Risk in Communities (ARIC) study.
Based on their levels of five established AF risk factors at baseline - namely high blood pressure, elevated body mass index, diabetes mellitus, cigarette smoking, and prior cardiac disease - each participant was classified as having an "optimal," "borderline," or "elevated" AF risk factor profile. The prevalence of each risk category was 5%, 28%, and 67%, respectively.
There were 1520 cases of incident AF during 17.1 years of follow-up. The age-adjusted incidence of AF varied by gender and race, at 7.45, 4.59, 5.27, and 3.67 per 1000 person-years in White men, White women, Black men, and Black women, respectively.
AF incidence also varied by risk factor profiles, at 2.19, 3.68, and 6.59 per 1000 person-years in people with optimal, borderline, and elevated AF risk factor profiles, respectively.
For any category of AF risk profile, White men had the highest rates and Black women the lowest rates of AF.
Among individuals with an optimal risk factor profile, the adjusted relative hazard for AF was 0.33, and in those with at least one borderline risk factor it was 0.50, compared with those with at least one elevated risk factor.
Finally, the researchers calculated that 56.5% of AF cases could be explained by having one or more borderline or elevated risk factors. Suboptimal blood pressure control was the most important contributor to the AF burden whereas just 3% of cases were attributable to diabetes mellitus.
Writing in the journal Circulation, Rachel Huxley (University of Minnesota, Minneapolis) and co-authors conclude: "These findings illustrate that, as with other forms of cardiovascular disease, more than half of the AF burden is potentially avoidable through the maintenance of optimal levels of classic cardiovascular risk factors, further reinforcing the need for effective primary prevention strategies that enable individuals to adopt and maintain healthy diet and behavioral patterns."
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By Joanna Lyford