Comparison of stroke risk according to sinus node disease, atrial fibrillation and bradycardia-tachycardia syndrome: A French nationwide cohort-study

Abstract

Atrial fibrillation (AF) may commonly be associated with sinus node disease (SND) presenting as the so-called bray-tachy syndrome (BTS). BTS and AF are known to be at risk for ischemic stroke (IS). It remains unclear whether the risk of IS is similar in patients with isolated SND. Our objective was to compare the risk of IS in AF, SND and BTS patients and to identify risk factors of stroke in patients with SND. This French longitudinal cohort study was based on the national hospitalization database, the Programme de médicalisation des systèmes d’information (PMSI). We included all patients over 18 y.o. in France from January 2010 to December 2015 hospitalized with a main or related diagnosis of AF or SND. Baseline characteristics were pooled into a multivariate Cox model to identify significant predictors of IS. Of 1,732,412 patients included after exclusion of pacemaker or implantable cardiac defibrillator patients (PM/ICD), 1,601,435 (92.44%) had AF, 102,849 (5.94%) SND and 28,128 (1.62%) BTS. Compared to patients with AF or BTS, those with SND were younger, had a lower CHA2DS2-VASc score. Incidence of IS during follow-up was higher in AF than in BTS patients (yearly rate 4.90% vs. 2.73%, P < 0.0001) and in AF than in SND (yearly rate 4.90% vs. 1.97%, P < 0.0001). In patients with SND, main independent predictors of IS during follow-up were age ≥ 75 y.o., hypertension, vascular disease, alcohol-related diagnoses and lung disease. Patients with SND and a CHA2DS2-VASc score ≥ 2 had a worse thromboembolic prognosis with a hazard ratio of 2.34 (95% CI 2.071–2.644, P < 0.0001) for IS occurrence compared to those with CHA2DS2-VASc score = 0 or 1. Patients with SND have a lower risk of thromboembolic events than those with AF or BTS. However, SND patients with a CHA2DS2-VASc score ≥ 2 had a markedly higher risk of IS during follow-up and may need specific considerations.