Use of biomarkers to assess tissue specific androgen adequacy: defining male hypogonadism.

PURPOSE: The criteria for normal testosterone have been established by expert consensus rather than by evidence. We determined whether a cutoff point for normal could be established using biomarkers. MATERIALS AND METHODS: We performed an exploratory investigation of 1,492 hypogonadal men pooled from 7 registration trials. Serum testosterone, prostate specific antigen and hematocrit were measured at baseline and after 90 days of continuous testosterone replacement therapy. RESULTS: Baseline prostate specific antigen, percent change in prostate specific antigen and hematocrit appeared to be most strongly related to baseline serum testosterone. Subgroup analysis and visual inspection of linear spline fit of these data suggested an approximate serum testosterone cutoff for normal of 300 ng/dl for percent change in hematocrit, and 200 ng/dl for baseline prostate specific antigen and percent change in prostate specific antigen. CONCLUSIONS: This exploratory study revealed considerable variation among individuals and target tissues in individuals. Further study should be performed using standardized assays in a broader population.

Risk of Severe COVID-19 in Prevalent Users of Alpha-1 Adrenergic Receptor Antagonists: A National Case-Control Study of Medicare Beneficiaries.

BACKGROUND: Alpha-1 adrenergic receptor antagonists prevent cytokine storm in mouse sepsis models. This led to the hypothesis that alpha-1 blockers may prevent severe coronavirus disease 2019 (COVID-19), which is characterized by hypercytokinemia and progressive respiratory failure. METHODS: We performed an observational case-control study in male Medicare beneficiaries aged 65 years or older, with or without benign prostatic hyperplasia (BPH), and treated with alpha-1 receptor blockers or 5-alpha reductase inhibitors. Adjusted odds ratios (aOR) and 95% confidence intervals (CI) were estimated for outcomes of uncomplicated and severe COVID-19 hospitalization (intensive care unit admission, invasive mechanical ventilation, or death). RESULTS: There were 20,963 cases of hospitalized COVID-19 matched to 101,161 controls on calendar date and neighborhood of residence. In the primary analysis (males with BPH), there was no difference in risk of uncomplicated COVID-19 hospitalization (aOR 1.08, 95% CI 0.996-1.17) or hospitalization with severe complications (aOR 0.97, 95% CI 0.88-1.08). In the secondary analysis (males with or without BPH), the corresponding aORs were 1.02 (95% CI, 0.96-1.09) (uncomplicated) and 0.99 (95% CI, 0.91-1.07) (complicated), respectively. Subgroup and sensitivity analyses yielded similar results. Of note, there was no difference in risk of severe COVID-19 hospitalization when comparing non-selective vs selective alpha-1 blocker use (aOR 0.98, 95% CI 0.86-1.10), higher- vs lower-dose alpha-1 blocker use (aOR 0.96, 95% CI 0.86-1.08), or current vs remote alpha-1 blocker use (aOR 1.04, 95% CI 0.91-1.18). CONCLUSIONS: Prevalent use of alpha-1 receptor blockers was not associated with a protective or harmful effect on risk of uncomplicated or severe hospitalized COVID-19.