Testosterone, SHBG Levels, and Heart Failure Risk: Does the Correlation Imply Causation?

The authors describe a meta-analysis of six observational studies with low risk of bias, which suggests a modest association between low testosterone levels, but not Sex Hormone-Binding Globulin (SHBG), and incidence of heart failure (HF) in men, but not in women. In short, for each reduction of one standard deviation of serum testosterone levels, the hazard ratio of HF increased 10% (HR 1.10, 95% CI: 1.03-1.17).

The polled data show that a total of 233,474 middle-aged participants were followed up for at least 7.7 years; the vast majority of them (90.2%) registered in one single cohort, 3,991 (1.71%) of them had events. In other words, we could observe a small absolute risk increase in comparison to the overall population. Among individuals aged ≥45 years, the incidence of HF is 6.0 per 1,000 person-years, increasing to 21.1 per 1,000 person-years among those aged 65 years or more.

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