JAMA Logo Atrial fibrillation (AF) usually characterized by an irregular and rapid heart rhythm is linked with genetic variants, or at least the following tidbit suggests so. A recent study claims that occurrence of AF in first-degree relatives elevates AF risk of an individual. The contribution of familial AF in anticipating new AF onset probably remains under wraps.

The study comprised 4,421 participants from the Framingham Heart Study with an average age of 54 years and 54 percent were women. The volunteers were free of AF at the beginning of the study and had at least 1 parent or sibling enrolled in the study. While the study began in 1948, follow up ended by December 2007. From 1968-2007, 440 volunteers were diagnosed with AF. 1,185 participants forming 26.8 percent reported familial AF and 351 subjects representing 7.9 percent had premature familial AF, wherein the condition begins by 65 years of age or younger.

Experts quote, “Future efforts should attempt to discern the factors that mediate the association between familial AF and AF risk, further explore the relationships between premature familial AF and risk prediction, and determine whether incorporating genetic variants into an AF prediction model enhances its performance.”

Among the 2,393 baseline examinations in which familial AF was present, 1,163 fathers, 1,068 mothers and 404 siblings were included in the investigation. Steven A. Lubitz, M.D., M.P.H., of the Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, Mass., and colleagues observed that 1 to 5 affected relatives had raised chances of familial AF in the volunteers. Almost 40 percent increased risk was probably faced by participants with familial AF. Even after taking AF risk factors of AF-related genetic variants into consideration the risk did not seem to alter. Authors conclude that threat of developing AF is correlated with increasing number of affected first-degree relatives.

The study is published online and will appear in the November 24 issue of JAMA.