Research already has suggested that men face a greater risk of severe illness and death from COVID-19. Now, scientists say male pattern baldness might actually be a risk factor, reports the Telegraph. "We really think that baldness is a perfect predictor of severity," says Brown University's Carlos Wambier, lead author of two small studies in Spain. The first study of 41 men admitted to Spanish hospitals with COVID-19 found 71% had male pattern baldness, which is estimated to affect 31% to 53% of white men. The second study of 122 men admitted to three Madrid hospitals with COVID-19 found 79% had male pattern baldness, reports Science. As male pattern baldness is linked to dihydrotestosterone—an androgen, or so-called "male" sex hormone—the thought is that androgens may boost the virus' ability to penetrate cells.
There is other evidence in support of this theory. For instance, a study of 42,000 men with prostate cancer in Veneto, Italy, found patients on androgen-deprivation therapy—drugs that reduce levels of androgens that fuel prostate cancer cells—were significantly less likely to fall ill, be hospitalized, or die of COVID-19 than men with prostate cancer who were not taking the drugs. These results are replicated in a second, still-unpublished study, whose author believes "androgen deprivation may limit those severe outcomes," per Science. A US trial is already underway to see if drugs that treat male pattern baldness (by blocking the conversion of testosterone to dihydrotestosterone) are effective at treating COVID-19. Another study of 200 veterans in Los Angeles, Seattle, and New York will analyze the effect of prostate cancer drugs, per the Telegraph. (More coronavirus stories.)