Research

Hormonal

Testosterone replacement therapy in middle-aged and older men significantly increases the risk of elevated hematocrit (>50%) and prostate events compared to placebo.

If you are an older man considering testosterone therapy, expect your blood thickness (hematocrit) and prostate markers (PSA) to rise. You must commit to regular blood tests and prostate exams. The risk of heart attacks or death does not appear to increase significantly, but the risk of thick blood and prostate issues does.

GoodSupportsHIGH confidence
The combined rate of all prostate events was significantly greater in testosterone-treated men than in placebo-treated men (OR = 1.78, 95% confidence interval [CI], 1.07–2.95)... Testosterone-treated men were nearly four times as likely to have hematocrit >50% as placebo-treated men (OR = 3.69, 95% CI, 1.82–7.51).
Olga M. Calof et al. · The Journals of Gerontology Series A · 2005

Why this rating

Meta-analysis of 19 randomized, placebo-controlled trials provides high-quality aggregate evidence, though heterogeneity exists.

Source

Adverse Events Associated With Testosterone Replacement in Middle-Aged and Older Men: A Meta-Analysis of Randomized, Placebo-Controlled Trials

Olga M. Calof et al. · The Journals of Gerontology Series A · 2005

DOI 10.1093/gerona/60.11.1451

Meta-analysis · 19 studiesCited 726×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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