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Among patients hospitalized for COVID-19, those who had been taking statins had a substantially lower risk of death in a new large observational study.
Results showed that use of statins prior to admission was linked to a greater than 40% reduction in mortality and a greater than 25% reduction in risk of developing a severe outcome.
The findings come an analysis of data from the American Heart Association's COVID-19 Cardiovascular Disease Registry on more than 10,000 patients hospitalized with COVID-19 at 104 hospitals across the United States published in PLoS One.
While several other studies have suggested benefits of statins in COVID-19, this is by far the largest study so far on this topic.
"I would say this is the most reliable study on statins in COVID-19 to date, with the results adjusted for many confounders, including socioeconomic factors and insurance type," lead author Lori B. Daniels, MD, told this news organization. "However, it still an observational study and therefore falls short of a randomized study. But I would think a randomized study of statins in COVID-19 is probably not feasible, so this study provides excellent data at an observational level."
After propensity matching for cardiovascular disease, results showed that most of the benefit of statins occurred in patients with known cardiovascular disease.
"While most patients taking statins will have cardiovascular disease, there are also many patients who take these drugs who don't have heart disease but do have cardiovascular risk factors, such as those with raised cholesterol, or a family history of cardiovascular disease. For [such patients], the effect of statins was also in the same direction but it was not significant. This doesn't exclude an effect," noted Daniels, who is professor of medicine and director of cardiovascular intensive care at the University of California, San Diego.
"We are not saying that everyone should rush out and take a statin if they do not have risk factors for cardiovascular in order to lower their risk of dying from COVID. But if individuals do have an indication for a statin and are not taking one of these dugs this is another good reason to start taking them now," she added.
The investigators embarked on the study because, although previous observational studies have found that statins may reduce the severity of COVID-19 infection, these studies have been limited in size with mostly single-center or regional studies, and some results have been conflicting. They therefore conducted the current, much larger analysis, in the AHA COVID-19 CVD Registry which systematically collected hospitalized patient–level data in a broad and diverse hospital and patient population across the United States.
For the analysis, the researchers analyzed data from 10,541 patients hospitalized with COVID-19 through September 2020 at 104 U.S. hospitals enrolled in the AHA registry to evaluate the associations between statin use and outcomes.
Most patients (71%) had either cardiovascular disease, hypertension, or both. Prior to admission, 42% of subjects used statins, with 7% being on statins alone and 35% on statins plus antihypertensives. Death (or discharge to hospice) occurred in 2,212 subjects (21%).
Results showed that outpatient use of statins, either alone or with antihypertensives, was associated with a 41% reduced risk of death (odds ratio, 0.59; 95% confidence interval, 0.50-0.69), after adjusting for demographic characteristics, underlying conditions, insurance status, hospital site, and concurrent medications. Statin use was also associated with a roughly 25% lower adjusted odds of developing severe disease.
Noting that patients on statins are also likely to be on antihypertensive medication, the researchers found that the statin benefit on mortality was seen in both patients taking a statin alone (OR, 0.54) and in those taking statins with an antihypertensive medication (OR, 0.60).
Use of antihypertensive drugs was associated with a smaller, albeit still substantial, 27% lower odds of death (OR, 0.73; 95% CI, 0.62-0.87).
In propensity-matched analyses, use of statins and/or antihypertensives was tied to a 32% reduced risk of death among those with a history of CVD and/or hypertension (OR, 0.68; 95% CI, 0.58-0.81). An observed 16% reduction in odds of death with statins and/or antihypertensive drugs among those without cardiovascular disease and/or hypertension was not statistically significant (OR, 0.84; 95% CI, 0.58-1.22).
Stabilizing the Underlying Disease
The researchers pointed out that the results of the propensity matching analysis are consistent with the hypothesis that the major benefit of these medications accrues from treating and/or stabilizing underlying disease.
"Although it is well known that statins improve long-term outcomes among patients with or at elevated risk for cardiovascular disease, the association with a large short-term benefit which accrues in the setting of hospitalization for COVID-19 is a new and intriguing finding," they said.
They cited several "plausible mechanisms whereby statins could directly mitigate outcomes in COVID-19 beyond treating underlying disease conditions," including anti-inflammatory effects and a direct inhibitory effect on the SARS-CoV-2 virus.
Daniels elaborated more on the potential mechanism at play in an interview: "I think what is happening is that the statin is stabilizing the coronary disease so patients are less likely to die from MI or stroke, and this gives them more time and strength to recover from COVID-19."
She added: "Statins may also have some direct anti-COVID effects such as an anti-inflammatory actions, but I would guess that this is probably not the primary effect behind what we're seeing here."
"Important Clinical Implications"
The authors say their findings have "important clinical implications."
They noted that early in the pandemic there was speculation that certain medications, including statins, and the ACE inhibitor/angiotensin receptor blocker (ARB) classes of antihypertensives may confer an increased susceptibility to COVID-19 positivity and/or severity.
"Our study reinforces the AHA and others' recommendations that not only is it safe to remain on these medications, but they may substantially reduce risk of severe COVID-19 and especially death from COVID-19, particularly statins, and particularly among those with associated underlying conditions," the authors stressed.
Daniels added that, although statins are very safe drugs, there are always some patients who prefer not to take medication even if indicated, and others who may have borderline indications and decide not to take a statin at present.
"This study may persuade these patients that taking a statin is the right thing to do. It may give those patients on the cusp of thinking about taking one of these drugs a reason to go ahead," she said.
"Provocative but Not Definitive"
Commenting on the study, Robert Harrington, MD, professor of medicine and chair of the department of medicine at Stanford (Calif.) University, said: "These are interesting observational data but as such have all the limitations of nonrandomized comparisons despite the best attempts to adjust for a variety of potential confounders. For example, is this an effect of statins (perhaps through some anti-inflammatory mechanism) or is it more an effect that can be attributed to the patients who are prescribed and taking a statin, compared with those who are not?"
He added: "The primary clinical benefit of statins, based on many large randomized clinical trials, seems to be derived from their LDL lowering effect. Observational studies have suggested potential benefits from anti-inflammatory effects of statins, but the randomized trials have not confirmed these observations. So, the current data are interesting, even provocative, but ultimately hypothesis generating rather than definitive."
Also commenting on the study, Steven Nissen, MD, professor of medicine at the Cleveland Clinic, said: "While statins have many established benefits, their role in preventing COVID-19 complications is very speculative. Like all observational studies, the current study must be viewed as hypothesis generating, not definitive evidence of benefit. There are many potential confounders. I'm skeptical."
The authors of this study received no specific funding for this work and report no competing interests. Harrington was AHA president when the COVID registry was created and he is still a member of the AHA board, which has oversight over the project.
This article originally appeared on MDedge.com, part of the Medscape Professional Network.
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Cite this: Statins Again Linked to Lower COVID-19 Mortality - Medscape - Jul 23, 2021.