An observed correlation between male-pattern hair loss and more severe COVID-19 symptoms has prompted some scientists to speculate that the hormone causing the hair loss may also make it easier for the coronavirus to attack the body's cells. This link might also help explain the increased risk of severity for men (58%) vs women (42%).
A small study of 41 patients found that 71% of men hospitalized with serious COVID-19 symptoms also had male-pattern baldness. It is estimated that 31-53% of a similar male population has male-pattern hair loss. Thus the incidence is higher than expected, offering preliminary support for a linkage.