Even slight BP elevations linked to increased AF incidence among women

April 2009

MedWire News: Blood pressure (BP) is strongly associated with incident atrial fibrillation (AF) among initially healthy women, with the systolic a better predictor than the diastolic measure, findings from the Women’s Health Study show.

Furthermore, the study indicates that BP values below the current threshold for the diagnosis of arterial hypertension are significantly associated with the risk for incident AF.

“Even slightly elevated BP levels at baseline imposed some degree of increased risk,” write study authors David Conen (University Hospital Basel, Switzerland) and colleagues in the journal Circulation.

Because treatment of established AF has limited long-term success and is associated with significant risks, characterizing treatable risk factors for AF has “substantial clinical relevance” the team notes.

The researchers prospectively followed up 34,211 women for incident AF over 12.4 years, and then compared the incidence of AF across systolic and diastolic BP categories.

The women were aged 55 years on average at baseline; during follow-up, 644 had at least one confirmed episode of AF.

Analysis showed that both systolic and diastolic BP components were significantly and strongly associated with incident AF, after multivariable adjustment.

Even women with high-normal systolic (130 to 139 mm Hg) or diastolic (85 to 89 mm Hg) BP at baseline had 28% and 53% increased risks for incident AF compared with women with systolic BP <120 mm Hg or diastolic BP <65 mm Hg, respectively.

In further continuous and combined hazard modeling, systolic BP remained significantly and strongly positively associated with AF incidence, whereas diastolic BP did not.

Of note, say Conen and co-workers, models incorporating BP measures updated over time showed that women with systolic BP values between 130 and 139 mm Hg during follow-up also had a significantly increased risk for subsequent AF.

The team concludes: “Taken together, our findings indicate that tight BP control may help to reduce the growing burden of AF in the community.”

Circulation 2009; 119: 2146–2152