New Delhi: Research in the past few months has found that hospitalised Covid-19 patients taking statins are less likely to die or be admitted in the intensive care unit (ICU).
Statins are a class of drugs that are commonly prescribed to help lower cholesterol levels. It is used by patients with diabetes (for primary prevention) and with cardiovascular disease (for secondary prevention). Recently, a study in the Nature Communications journal by researchers in the US and Sweden found that the use of statins was associated with lower mortality in hospitals.
Death in the group that was not on statins occurred in 26.5 per cent of cases, which was higher when compared to the group on statins. “Patients with antecedent statins use had lower rates of in-hospital mortality at any time compared with individuals who were not on statins (20.8% vs. 33.7%),” the study stated.
“Statins have what we called pleiotropic effects, which means (its) effects (are) beyond cholesterol lowering which is the primary function of the drug, and that’s quite a well known and well established fact,” Dr Ambuj Roy, professor of cardiology at AIIMS, told ThePrint.
He added, “There is interest in repurposing it for Covid-19, because it has anti-inflammatory (effects) which then decrease a lot of pathways that could potentially be one of the pathways that causes Covid in the body.”
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What studies say
The study was a retrospective analysis i.e., a study that uses existing data — in this case, of 1,296 patients, among whom 648 were statin users and 648 were non-statin users.
The study used data of patients who had been admitted to hospitals in the US between 1 February through 12 May 2020, and had tested positive for SARS-CoV-2, the virus that causes Covid-19.
Using this data, researchers constructed a model that was used to analyse the association between statin-use and in-hospital mortality for a period of 30 days.
In the multivariable-adjusted analysis that involves more than two variables, the use of statins led to a nearly 50 per cent decrease in in-hospital mortality. A 2020 study by researchers in Singapore, based on a retrospective analysis of 717 patients, also showed that statin users were less likely to be admitted to the intensive care unit (ICU).
Another study, a preprint, by researchers in the US, Canada and South Korea had found that among non-ICU patients, statin users were at a lower risk of mortality relative to non-statin users. Also, patients who were administered statins after their Covid-19 diagnosis were at a lower risk of mortality, the study said.
There was also a retrospective study published in the Translational Medicine Communications this January, which said “that statin use appeared to be associated with a lower risk of morbidity and lower risk of death”.
Researchers for this study, however, highlighted the need for randomised controlled trials (RCT) and extensive retrospective studies to further evaluate and validate the “potential beneficial effects of statin treatment on clinical symptoms and mortality rates associated with Covid-19”.
RCTs are trials where subjects are randomly assigned to two groups which receive different treatments.
Asserting the point about the need for RCTs, Dr Roy at AIIMS said, “All these [studies] are observational that have a huge bias in terms of the way you select the patients. For example, if you’re on statins, the risk of cardiovascular disease goes down, and cardiovascular disease is a risk for Covid. If you’re at a lower risk, maybe it is acting through that pathway … we can’t be sure.”
He added, “So to establish causality, you always do what is a randomised control trial.”
AIIMS has been conducting an RCT involving almost 900 patients since July 2020. Dr Roy, who said he couldn’t disclose the study’s findings, noted, “I can only hint that when you do a trial, you often don’t get results that you see in observational studies.”
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About statins & its use
The American College of Cardiology (ACC) and the American Heart Association (AHA) in their joint guidelines on Primary Prevention of Cardiovascular Disease have been advocating the use of statins for the management of cholesterol for several years now.
According to the AHA, statins work by disrupting the production of cholesterol by blocking a specific enzyme inside cholesterol-producing liver cells.
They also have anti-inflammatory effects brought on by reducing agents like C-reactive protein and adhesion molecules that have been known to increase in patients with coronary artery disease.
Since it is generally prescribed to those with cardiovascular diseases, the use of statins is fairly extensive.
“It is a well established drug for secondary-prevention, meaning anybody who has cardiovascular disease like prior stroke, heart disease in terms of MI (Myocardial infarction) or bypass or have had a paralytic brain stroke, should be on a statin. And then a lot of diabetics, generally more than 50-55 years of age,” Dr Roy said.
He added, “In terms of eligibility, I think 10 per cent of the adult population should be eligible to take statins.”
Studies from 2014 and 2017 had also noted the growing use of statins.
A population-based cross-sectional study by researchers at Christian Medical College (CMC), Vellore in Tamil Nadu, had assessed the use of statin among those with diabetes and coronary heart diseases.
The study involved people from rural and urban Vellore and found that 37.7 per cent with coronary heart disease were taking statins while less than 20 per cent of patients with diabetes used the drugs.
Noting the growing use of the drug, the CMC study stated, “The rate of current statin use in 2016 among the 219 diabetics who were interviewed was 17.0% while among diabetics aged 40 years or older it was 16.6%, which shows an increase from 7.4% and 7.7% respectively in 2010–2012.”
In 2014, researchers had analysed the sale of statins, rate of statin prescriptions and also noted its growing use.
(Edited by Manasa Mohan)
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