Better Long-Term Outcomes in Ischemic Stroke Patients with Atrial Fibrillation Treated with Warfarin at Discharge

Compared to patients who received no oral anticoagulant treatment at hospital discharge, patients with ischemic stroke and atrial fibrillation who received warfarin had a lower risk of major adverse cardiovascular events and spent less time receiving follow-up care at the hospital.

A new analysis of 12,552 strokes indicates that initiating warfarin during hospitalization and continuing it afterward improves outcomes among patients with atrial fibrillation (AF) who are not already taking the drug.

Researchers pulled data on warfarin-naïve AF patients who suffered ischemic stroke between 2009 and 2011 from 1,487 hospitals that participated in the Get with the Guidelines stroke program during that period. They then used long-term Medicare claims data to compare outcomes of patients who were discharged with warfarin prescriptions and those who received no prescription anticoagulation.

Overall, 11,039 (88%) of the patients received warfarin prescriptions. Members of this warfarin group tended to be slightly younger and to have less history of stroke or coronary disease than patients who got no warfarin, but the cohorts were comparable by other measures, including event severity scores on the National Institutes of Health Stroke Scale.

Warfarin group members nevertheless fared considerably better than other patients after discharge. They spent significantly more of the next 2 years living at home (rather than at healthcare facilities) than their untreated counterparts (adjusted home time difference, 47.6 days; 99% confidence interval [CI], 26.9-68.2 days). They also, over the same period of time, suffered significantly fewer major adverse cardiovascular events (adjusted hazard ratio [HR], 0.87; 99% CI, 0.78-0.98), fewer additional cases of ischemic stroke (HR, 0.63; 95% CI, 0.48-0.83) and lower all-cause mortality (HR, 0.72; 95% CI, 0.63-0.84).

Subgroup analysis, moreover, found a similar association between warfarin usage and improved outcomes in patients of both sexes, all races and all age categories, no matter what their records indicated about their history of cardiovascular disease or the severity of the stroke they suffered at baseline.

Indeed, the results were so consistent across the cohort as a whole and the various subgroups that study authors ended their paper, which appeared in the British Medical Journal, with an utterly unequivocal conclusion: “Among ischemic stroke patients with atrial fibrillation, warfarin treatment was associated with improved long term clinical outcomes and more days at home.”

The authors further argue that their work, which was funded by the Patient-Centered Outcomes Research Institute, supports the routine use of warfarin in eligible ischemic stroke patients who also have AF, particularly those who are female, older than 79 years or the victims of more severe strokes.

An editorial that accompanied the article argued not only in support of the study’s conclusions but also in support of the study’s general strategies for using existing data in an effort to provide a fact-based answer to an important question that had yet to be studied.

“It is time now to take stock of how much patient-centered research we are doing, how well we are doing it, and whether it improves health care,” wrote Thomas W. Concannon, a senior policy researcher at the Rand Corporation and an assistant professor at the Tufts University School of Medicine in Boston.

“In the linked paper, Xian and colleagues present a solid example of how to refocus research on questions, outcomes, and approaches that could help patients and clinicians to make better healthcare decisions.”