Association Between Age and Bleeding Events of Different Severities Among Patients with Nonvalvular Atrial Fibrillation in a Managed Care Population

Risk of bleeding is an important consideration among patients with nonvalvular atrial fibrillation (NVAF) due to the need for stroke prevention through anticoagulation. Older patients may be at risk for more frequent or more severe bleeding events.

To describe the incidence of bleeding events in various age groups of patients with NVAF.

Administrative claims data were used for this retrospective study. Adults with healthcare claims data related to atrial fibrillation (ICD-9-CM 427.31) between Jan 2005 and Jun 2009 but no evidence of valvular disease were included. Patients were followed until the earliest of death, disenrollment from the health plan, or 30 Jun 2010. Bleeding events in the follow-up period were categorized as major, serious non-major, or minor. A bleeding event was considered major if it was associated with any of the following: inpatient care, blood transfusion, decreased hemoglobin or hematocrit, physician guided medical or surgical treatment, intracranial bleed, or death. Serious non-major events were those involving vascular injury or critical site bleeding and were associated with outpatient hospital care or an emergency department visit. Minor bleeds were those associated with noncritical anatomical sites and an emergency department, outpatient hospital, or office visit. Patients were grouped based on their age as of the first atrial fibrillation diagnosis: younger than 65 years or 65 years and older; bleeding events in the subgroup of patients aged 75 years and older were also examined.

The mean (SD) age of the study sample (N=48,260) was 67 (13) years and 62.2% of the patients were male. Mean (SD) follow-up duration was 802 (540) days (median 673 days). Event rates for major bleeds were 5.2 events per 100 patient-years for patients aged younger than 65 years and 13.9 major bleeds per 100 patient-years for patients aged 65 years and older. Patients aged 75 and older had 15.6 major bleeds per 100 patient-years. Approximately 38.9% of all bleeding events experienced by patients aged 65 years and older were major. Approximately 23.3%, 33.6%, and 35.8% of major bleeds among patients younger than 65 years, 65 years and older, and 75 years and older, respectively, were associated with a hospitalization. Corresponding event rates for incident bleeds associated with an inpatient stay were 4.7 bleeding events per 100 patient-years for patients aged younger than 65 years, 12.0 events per 100 patient-years for patients aged 65 years and older, and 13.6 events per 100 patient-years for patients aged 75 years and older.

Increasing age was associated with increased rate of any type of bleeding. The increase in rate with increasing age was particularly notable for major bleeds.

Deitelzweig:Bristol-Myers Squibb/OptumInsight: Research Funding, Speakers Bureau. Pinsky:OptumInsight: Employment. Buysman:OptumInsight: Employment. Lacey:OptumInsight: Employment. Jing:Bristol-Myers Squibb: Employment, Equity Ownership. Wiederkehr:Pfizer: Employment, Equity Ownership. Graham:Bristol-Myers Squibb: Employment, Equity Ownership.