Chris Iliades, MD is a regular contributor to Bottom Line Health. He was an ear, nose, throat, head, and neck surgeon before becoming a full-time medical writer.
Hospital records during the COVID-19 pandemic show that men are more likely to be hospitalized for severe COVID than women. Blood testing on many male patients admitted for COVID reveal that they have lower levels of testosterone than men in the healthy, general population, according to several studies. Researchers at Washington University School of Medicine in St Louis had found that men admitted to their hospital with COVID commonly had low testosterone.
Which Came First? Low Testosterone or COVID?
Low testosterone is common in many older men because testosterone levels start to decline after age 30 and continue to drop by one to two percent every year. Testosterone levels also go down during a severe illness such as COVID, so researchers from Saint Louis University School of Medicine and Washington University School of Medicine conducted a study designed to find out which comes first, low testosterone or COVID-19.
Their study is published in the American Medical Society journal JAMA Network Open, and it suggests that men who have low testosterone before a COVID infection are at higher risk for COVID hospitalization than men with normal testosterone. The research team reviewed the hospital records of 723 men who tested positive for COVID, mostly in 2020. To be included in the study they had to have had a testosterone level tested before their hospital admission. The study identified and included all 723 men, who were at an average age of about 55.
Of the 723 men in the study, 116 had low testosterone before their admission and 180 had low testosterone that was being treated with testosterone replacement. The rest of the men, numbering 427, had normal testosterone. These were the key findings…
The research team concludes from the study that low testosterone is a risk factor for a more severe COVID infection along with other risk factors such as older age, obesity, diabetes, hypertension, chronic lung diseases and cardiovascular disease.
What’s the Normal Testosterone Range?
A normal range of testosterone for men is between 300 to 1,000 nanograms per deciliter (ng/dL). In their study, the investigators found that the risk of severe COVID starts with testosterone under 200 ng/dL. This risk occurs independent of other severe COVID risk factors.
Symptoms of low testosterone can include loss of sex drive, erectile dysfunction, depression, irritability, weakness, fatigue, and loss of muscle mass. These symptoms can cause a lower quality of life and can be treated with testosterone replacement therapy.
Testosterone Therapy Is Not Risk Free
The findings of the study suggest that correcting low testosterone can be a strategy for preventing severe COVID, along with vaccination. However, testosterone replacement therapy has some risks. Testosterone may increase the risk of prostate cancer or the risk from prostate cancer because testosterone speeds the growth of prostate cancer cells. Testosterone therapy has also been linked to a higher risk of heart disease in some studies, but this link is not as well established as the prostate cancer link.
Before testosterone replacement can be recommended as a risk reduction strategy for COVID, more research will need to be done. This study was an observational study, meaning it relied on a review of medical records. To prove that low testosterone is a risk factor for COVID, studies will need to compare men with low testosterone to men with normal testosterone going forward over time (a longitudinal study).