Aspirin remains one of the most widely used medications among older adults in the US, with more than 40% of individuals aged 60 and above taking it daily to prevent potentially fatal blood clots linked to heart attacks or strokes.
In recent years, however, experts have tempered their endorsement of universal aspirin therapy for older adults following studies indicating an increased risk of major bleeding that often outweighs the benefits in preventing initial cardiovascular events.
Nonetheless, it continues to be recommended selectively for individuals who have previously experienced heart attacks or strokes to prevent recurrence.
Given aspirin’s association with significant bleeding risks, including aneurysms, researchers sought to investigate its potential role in subtler forms of blood loss, such as that leading to anemia – a condition characterized by low red blood cell count or insufficient hemoglobin to transport oxygen efficiently.
Anemia, though less prominently discussed compared to cardiovascular events, affects a substantial number of elderly individuals globally, with studies showing a prevalence of 30% among adults aged 75 and older.
It is linked to various health complications including fatigue, cognitive impairment, depression, and heightened mortality risk.
A study published in the Annals of Internal Medicine on Monday tracked over 18,000 adults aged 65 and older from the US and Australia.
Half of the participants received a daily low-dose aspirin (100 milligrams), while the other half took a placebo.
Over approximately five years, participants underwent annual medical examinations and blood tests measuring hemoglobin and ferritin levels, a protein crucial for iron storage in red blood cells.
The study revealed a modest yet discernible difference: adults taking aspirin were 20% more likely to develop anemia compared to those on placebo.
Researchers estimated that within five years, 24% of seniors in the aspirin group would develop anemia, versus 20% in the placebo group.
Additionally, individuals on the aspirin regimen exhibited slightly lower levels of hemoglobin and ferritin, impacting their blood cells’ ability to effectively transport oxygen.
Even after adjusting for variables such as cancer, major bleeding events, age, gender, diabetes, kidney disease, and use of nonsteroidal anti-inflammatory drugs (NSAIDs), the association between aspirin use and increased risk of anemia persisted.
While the study did not pinpoint the exact mechanisms through which aspirin contributes to anemia, researchers hypothesize that its anti-clotting properties, which inhibit platelet aggregation and Cox-1 enzyme activity crucial for gastrointestinal lining maintenance, may play a role.
This could potentially lead to chronic low-level bleeding in the gut, culminating in anemia over time.
Given these findings, the researchers recommend heightened vigilance among healthcare providers in monitoring hemoglobin levels, particularly in patients with multiple risk factors including inflammatory conditions like arthritis or chronic kidney disease, who may also be using aspirin.
The study underscores the need for nuanced consideration of aspirin’s risks and benefits, particularly in older adults with complex medical profiles, to optimize cardiovascular protection while minimizing potential adverse effects on blood health.
