Impact of advanced age on management and prognosis in atrial fibrillation: insights from a population-based study in general practice

OBJECTIVES: to examine the use of antithrombotic therapy and predictors of stroke and death in very elderly (≥85 years) atrial fibrillation (AF) patients in a general practice cohort from the UK.

DESIGN: retrospective, observational cohort study; 12-month follow-up period.

SETTING: eleven general practices serving the town of Darlington, England representing a population of 105,000 patients.

PATIENTS: two thousand two hundred and fifty-nine patients with a history of AF, 561 (24.8%) aged ≥85 years.

MAIN OUTCOME MEASURES: use of antithrombotic therapy by age group and predictors of stroke and death.

RESULTS: five hundred and sixty-one (24.8%) AF patients aged ≥85 years (mean (SD) age 89 (4) years; 66% female) identified with a mean CHA2DS2-VASc score of 4.6 (SD 1.4). Thirty-six per cent received oral anticoagulation (OAC) compared with 57% in the 75-84 years age group. Forty-nine per cent of the very elderly received antiplatelet (AP) monotherapy; recorded OAC contraindications and declines were greatest among those aged ≥85 years. Stroke risk was highest among the very elderly (5.2% per annum), despite anticoagulation (3.9%). Multivariate analyses demonstrated an increased risk of stroke with AP monotherapy (odds ratio (OR) 2.45, 95% confidence intervals (CIs) 1.05-5.70) and a significant reduction in all-cause mortality with OAC therapy (OR 0.59, 95% CI 0.36-0.99).

CONCLUSION: the majority of very elderly AF patients in general practice do not receive OAC despite their higher stroke risk; almost half received AP monotherapy. AP use independently increased the risk of stroke, signifying that effective stroke prevention requires OAC regardless of age, except where true contraindications exist.