No stroke risk decline in atrial fibrillation patients over the last decadeChamberlain AM, et al. J Am Heart Assoc. 2016
No Decline in the Risk of Stroke Following Incident Atrial Fibrillation Since 2000 in the Community: A Concerning Trend
Chamberlain AM, Brown RD, Alonso A, et al.
J Am Heart Assoc. 2016;5: published online ahead of print
BackgroundAtrial fibrillation (AF), the most common sustained cardiac arrhythmia, is associated with a 5-fold increased risk of stroke and a 2-fold increased risk of mortality [1–4]. Since 1958, survival and the incidence of stroke due to AF have improved, however, recent data suggest that the incidence of AF has stabilised, and that mortality due to AF and stroke has not improved further [5-7].
In this study, the incidence of ischemic stroke (IS) and transient ischemic attack (TIA) between 2000 and 2010 was evaluated in 3247 patients with AF who experienced an IS/TIA and 3265 who experienced a TIA (patients who experienced an IS/TIA at the same day of incident AF were excluded).
- Over a mean follow-up of 4.6 years, 321 patients (10%) had IS, (n=221) or a transient ischemic attack (TIA, n=100).
- The incidence rates per 100 person-years were 2.14 (95% CI: 1.91–2.38) for IS/TIA and 1.54 (95% CI: 1.35–1.75) for IS.
- After adjustment for demographics and comorbidities, the hazard ratio (HR) of IS/TIA per year of AF diagnosis was 1.00 (95% CI: 0.96–1.04; P=0.80).
- No temporal trend was observed when considering IS alone (HR: 1.01; 95% CI: 0.96–1.06; P=0.73).
- There was no evidence of an improvement in survival over time among the 321 patients who developed IS/TIA (adjusted HR of death within 30 days of IS/TIA per year of AF diagnosis: 1.37; 95% CI: 0.99–1.88; P=0.06).
- There was no evidence of a difference in the risk of haemorrhagic strokes (n=41) over time per year of AF diagnosis after adjustment (HR: 0.97; 95% CI: 0.87–1.08; P=0.57).
- In patients diagnosed with AF from 2004 to 2010, the cumulative incidence of anticoagulation use was 40.0% (95% CI: 37.8% - 42.1%) at 30 days after diagnosis and 50.8% (95% CI: 48.5% - 53.0%) at 1 year after AF diagnosis.
- Predictors of IS and TIA were increasing age (only after adjusting for sex) and a history of IS/TIA (after adjusting for age and sex)
IS and TIA are frequent in patients with AF, occurring in 10% of patients after 5 years of follow-up. The occurrence of IS/TIA did not decline over the last decade, which may be associated with the underutilisation of anticoagulation. These data support the importance of AF screening and the need for treatment optimisation in these patients.
Find this article online
1. Go AS, Hylek EM, Phillips KA, et al. Prevalence of diagnosed atrial fibrillation in adults: national implications for rhythm management and stroke prevention: the anticoagulation and risk factors in atrial fibrillation (ATRIA) study. JAMA. 2001;285:2370–2375.
2. Wolf PA, Abbott RD, Kannel WB. Atrial fibrillation as an independent risk factor for stroke: the Framingham Study. Stroke. 1991;22:983–988.
3. Benjamin EJ, Wolf PA, D’Agostino RB, et al. Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation. 1998;98:946–952.
4. Krahn AD, Manfreda J, Tate RB, et al. The natural history of atrial fibrillation: incidence, risk factors, and prognosis in the Manitoba Follow-Up Study. Am J Med. 1995;98:476–484.
5. Schnabel RB, Yin X, Gona P, et al. 50 year trends in atrial fibrillation prevalence, incidence, risk factors, and mortality in the Framingham Heart Study: a cohort study. Lancet. 2015;386:154–162.
6. Chamberlain AM, Gersh BJ, Alonso A, et al. Decade-long trends in atrial fibrillation incidence and survival: a community study. Am J Med. 2015;128:260–267.
7. Miyasaka Y, Barnes ME, Bailey KR, et al. Mortality trends in patients diagnosed with first atrial fibrillation: a 21-year community-based study. J Am Coll Cardiol. 2007;49:986–992.