Among patients with atrial fibrillation, obstructive sleep apnea was an independent risk factor for major adverse CV and neurologic events, particularly stroke, according to findings published in the American Heart Journal.
In a retrospective cohort study using data from the ORBIT-AF I and ORBIT-AF II registries, researchers found that for patients with AF, the presence of obstructive sleep apnea (OSA) was significantly associated with major adverse CV and neurologic events (MACNE; adjusted HR = 1.16; 95% CI, 1.03-1.31) during mean follow-up of 1.5 years.
The researchers also found OSA was an independent risk factor for stroke beyond the CHA2DS2-VASc risk score (HR = 1.38; 95% CI, 1.12-1.7). However, it was not independently associated with CV death, MI, new-onset HF or major bleeding individually, according to the study.
“This raises the hypothesis that OSA may be a useful marker of stroke risk in patients who might not qualify based on the CHA2DS2-VASc score alone,” Frederik Dalgaard, MD, PhD, fellow at the Herlev and Gentofte Hospital at the Copenhagen Cardiovascular Research Center in Denmark, and colleagues wrote. “We confirmed that patients with CHA2DS2-VASc < 2 had a low risk of stroke (less than 1%), but there was a higher incidence of stroke in OSA patients compared to those without. Thus, in evaluating borderline cases in patients with stroke risk, OSA might be valuable in the treatment decision.”
Compared with patients from the study who did not have OSA, those who had it were younger (median, 68 years vs. 74 years), were more likely to be male (71% vs. 55%) and had elevated BMI (median, 34.6 kg/m2 vs. 28.7 kg/m2). Patients with AF and OSA also had a higher prevalence of concomitant comorbidities such as diabetes, chronic obstructive pulmonary disease and HF in addition to higher use of antithrombotic therapy.
Of the patients in the overall cohort (n = 22,760; mean age, 73 years; 58% men; 88% white; 28% with diabetes; 48% current smokers), 17.8% had OSA at baseline and 1,895 patients experienced an MACNE during the study period, according to the researchers.
“The addition of OSA to a risk model containing the CHA2DS2-VASc risk factors resulted in improved discrimination that was statistically significant, but the improvement in discrimination was very modest and clinically insignificant,” the researchers wrote. “This leads us to speculate that it might not be OSA itself that drives the increased risk of MACNE, as much as the cardiovascular disease and risk factors that accompany OSA.” – by Scott Buzby
Disclosures: Dalgaard reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.