This article is more than 5 years old. Information may no longer be current.
Sibling history of stroke confers elevated risk in AF
Patients with atrial fibrillation may have significantly greater risk for ischemic stroke if they have a sibling who had a stroke, according to findings published in the Journal of the American Heart Association.
After adjustment for covariates including age, sex, period of AF diagnosis, ICD codes and CHA2DS2-VASc score, researchers found that patients with AF experienced elevated risk for ischemic stroke if they had a sibling with ischemic stroke (HR = 1.31; 95% CI, 1.23-1.4) or both ischemic stroke and AF (HR = 1.36; 95% CI, 1.24-1.49).
Moreover, patients with a sibling with stroke had greater all-cause mortality risk compared with patients without one (HR = 1.09; 95% CI, 1.05-1.14).
“Our results suggest that a sibling history of stroke remains a contributor in those at high risk for cardioembolic stroke, but does not support a substantially higher heritable contribution in this population,” John Berntsson, MD, of the department of clinical sciences of Skäne University Hospital at the Lund University Clinical Research Centre, Malmö, Sweden, and colleagues wrote. “Genome-wide association studies have identified several loci associated with stroke, many of them sharing genetic associations with other vascular traits, such as hypertension (Malik R, et al. Nat Genet. 2018;doi:10.1038/s41588-018-0058-3.) Not surprisingly, the heritability varies among the different subtypes, and seems to be highest for cardioembolic stroke (30%) and large-vessel disease (40%)(Bevan S, et al. Stroke. 2012;doi:10.1161/STROKEAHA.112.665760.)”
In other findings, the risk for stroke was marginally increased in patients with AF who had a husband with ischemic stroke (HR = 1.05; 95% CI, 1.02-1.09) or a wife with ischemic stroke (HR = 1.05; 95% CI, 1.01-1.08).
For this nationwide study, researchers in Sweden identified 113,988 patients with AF, ischemic stroke and their familial relations (mean age, 60 years; 31% women) using data from the Swedish Multi-Generation Register and Cause of Death Register.
“Our results suggest that family predisposition of stroke could contribute to the assessment of stroke risk in patients with AF,” the researchers wrote. “Whether information about family predisposition of stroke could improve the prediction of ischemic stroke compared with traditional risk factor scores, such as the CHA2DS2-VASc, should be examined in future studies.” – by Scott Buzby
Disclosures: One author reports he received sponsored research support from Bayer HealthCare, Boehringer Ingelheim and Bristol-Myers Squibb/Pfizer; and has consulted for Abbott, Bristol-Myers Squibb/Pfizer and Quest Diagnostics. The other authors report no relevant financial disclosures.