Update: Study linking hydroxychloroquine to increased death risk is retracted

Editor’s note: The study referenced in this story has been retracted by the medical journal The Lancet due to questions on the veracity of its primary data sources. Read more here.

Coronavirus patients who took hydroxychloroquine or its related drug chloroquine were more likely to die or develop an irregular heart rhythm that can lead to sudden cardiac death, compared to those who did nothing, a retrospective review published in The Lancet shows.

Why it matters: Despite warnings from the Food and Drug Administration, President Trump has insisted the anti-malarial drug as a "game-changer" and admitted he has taken it as a preventative even though the drug is unproven.

The big picture: The medical journal's review consisted of 96,000 hospitalized patients diagnosed with the coronavirus in six continents, the largest analysis of medical records on the drug, between Dec. 20, 2019, and April 14, 2020.

• About 15,000 of the 96,000 patients were treated with hydroxychloroquine or chloroquine alone, or combined with an antibiotic known as a macrolide.

The findings: Those given the drug alone had a 34% increased risk of dying and a 137% increased risk of heart arrhythmias.

• Those who took the drug paired with an antibiotic had a 45% increased risk of death and a 411% risk of heart arrhythmias. This combination is one President Trump has been encouraging.

The mean age of patients was 54 years old and 53% were men.

• Those excluded were those on mechanical ventilators or who received remdesivir, an antiviral drug made by Gilead Sciences.

The bottom line: The FDA has adamantly warned against taking hydroxychloroquine or chloroquine because of the risk of heart complications and unproven claims it prevents COVID-19 infections.

Go deeper: Stunned Fox News host reacts to Trump taking hydroxychloroquine