(HealthDay News) — For older adults, low-dose aspirin is associated with increased incident anemia and a decrease in ferritin when compared with placebo, according to a study published online in the Annals of Internal Medicine.
Zoe K. McQuilten, MBBS, PhD, from Monash University in Melbourne, Australia, and colleagues examined the effect of low-dose aspirin on incident anemia, hemoglobin, and serum ferritin concentrations in a post hoc analysis of the ASPirin in Reducing Events in the Elderly trial involving community-dwelling individuals aged 70 years or older. A total of 19,114 individuals were randomly assigned to 100 mg of aspirin daily or placebo.
The researchers found that the incidence of anemia was 51.2 events per 1,000 person-years and 42.9 events per 1000 person-years in the aspirin and placebo groups, respectively (hazard ratio, 1.20). In the placebo group, hemoglobin concentrations decreased by 3.6 g/L per 5 years, while a steeper decline of 0.6 g/L per 5 years was experienced by the aspirin group. In 7139 participants with ferritin measures at baseline and year 3, the prevalence of ferritin levels <45 µg/L at year 3 was greater in the aspirin group (13 vs 9.8%); the aspirin group also had a greater overall decline in ferritin by 11.5% when compared with those receiving placebo. Similar results were seen in a sensitivity analysis quantifying the effect of aspirin in the absence of major bleeding.
“Daily low-dose aspirin increased the risk for incident anemia by approximately 20%, which, after taking into account risk for clinically significant bleeding, was most likely due to occult blood loss given the observed steeper decline in ferritin in participants allocated to aspirin,” the authors write.
Several authors disclosed financial ties to industry.