— Results more favorable for older people, those with comorbidities
by Nicole Lou
People with moderate COVID-19 illness tended to have better clinical outcomes if they took aspirin their first day in the hospital, according to data from the NIH’s National COVID Cohort Collaborative.
In a large observational cohort study, early aspirin use was associated with lower in-hospital mortality rates by 28 days (10.2% vs 11.8% with no aspirin, OR 0.85, 95% CI 0.79-0.92) with no significant increase in hemorrhagic complications such as GI or cerebral bleeding.
With early aspirin, pulmonary embolism was down, but not deep vein thrombosis, reported the ANCHOR group led by Jonathan Chow, MD, of George Washington University School of Medicine and Health Sciences in Washington, D.C.
The authors said their study, published in JAMA Network Open, should leave the book open for aspirin in moderate COVID-19.
“Despite widespread vaccination efforts in wealthy countries, only 10% of the population in low-income countries is vaccinated. With low global vaccination rates and overwhelmed health systems, there continues to be a need for COVID-19 treatments, particularly in patients with moderate to severe disease,” the investigators wrote.
“A randomized clinical trial that includes diverse patients with moderate COVID-19 is warranted to adequately evaluate aspirin’s efficacy in patients with high-risk conditions,” according to them.
Yet the U.K.’s pragmatic RECOVERY trial came to a different conclusion, finding all-cause mortality to be similar between aspirin and placebo groups, albeit with a small effect on discharge alive within 28 days in patients who received aspirin.
More recently, the REMAP-CAP trial recently found antiplatelets to be unhelpful for COVID patients in the ICU.
Chow and colleagues suggested that the mixed results of RECOVERY may be related to the study excluding people on antiplatelets prior to hospitalization and the participants’ relatively low prevalence of comorbidities.
In ANCHOR, those who appeared to benefit the most from early aspirin were patients older than 60 years and people with comorbidities, they reported.
“This is our third study and the culmination of 15 months of work looking at aspirin use in hospitalized COVID-19 patients. We continue to find that aspirin use is associated with improved outcomes and lower rates of death in hospitalized patients. What’s more, it’s low cost and readily available, which is important in parts of the world where more expensive therapeutics might not be as accessible,” Chow said in a press release.
The ANCHOR study was based on a data repository that pooled EHR files on COVID patients.
Included were 112,269 people with moderate COVID-19 hospitalized across 64 health systems in the U.S., of whom 13.6% received aspirin on the first day of admission.
Notably, the trial data set came from the period from Jan. 1 to Sept. 10, 2020 — well before the platform trials reported that therapeutic anticoagulation with heparin improved survival in hospitalized, non-critically ill COVID-19 patients.
In ANCHOR, 8.0% of the aspirin group and 1.2% of the no-aspirin group got therapeutic heparin by the first day of admission, which evened out to about 2.6% with inverse probability of treatment weighting.
By contrast, in RECOVERY, 34% of patients were on therapeutic-dose heparin and 60% were on standard prophylactic-dose heparin at randomization. In the REMAP-CAP ICU trial, background anticoagulation was standard.
The RECOVERY authors had suggested that the anticoagulation provided adequate antithrombotic therapy that the antiplatelet didn’t improve on, writing: “The absence of meaningful benefit from aspirin in our trial could be because anti-platelet therapy confers no clinically significant additional benefit on top of high rates of anti-thrombotic therapy with LMWH [low molecular weight heparin] and corticosteroid treatment diminishing thromboinflammatory stimulation.”
Aspirin use in ANCHOR lasted a median 5 days and was more likely in people with chronic kidney disease, chronic obstructive pulmonary disease, heart disease, hypertension, and diabetes.
The overall cohort had a median age of 63, with 52.7% white patients, 16.1% Black patients, and 3.8% Asian patients.
The retrospective study design left room for miscoding or underreporting of certain outcomes, the authors acknowledged.