Effect of sex steroid use on cardiovascular risk in transsexual individuals: a systematic review and meta‐analyses

Abstract

P>Objective To summarize the available evidence on the cardiovascular effects of cross-sex steroid use in transsexuals. Methods We searched relevant electronic databases and sought additional references from experts. Eligible studies reported on cardiovascular events, venous thromboembolism, blood pressure and fasting serum lipids. Data were extracted in duplicate. We used the random-effects model to estimate the pooled weighted mean difference (WMD) and 95% confidence intervals (CIs). Results We found 16 eligible studies, mostly uncontrolled cohorts of varied follow-up durations (1471 male-to-female (MF) and 651 female-to-male (FM) individuals). In the MF individuals, cross-sex hormone use was associated with a statistically significant increase in fasting serum triglycerides without changes in the other parameters (WMD = 23 center dot 39 mg/dl; 95% CI = 4 center dot 82-41 center dot 95). In the FM individuals, there was a similar increase of triglycerides (WMD = 31 center dot 35 mg/dl; 95% CI = 7 center dot 53-55 center dot 17) and a reduction of high density lipoprotein (HDL)-cholesterol (WMD = -6 center dot 09 mg/dl; 95% CI = -11 center dot 44 to -0 center dot 73). There was a statistically significant but clinically trivial increase in systolic blood pressure (WMD = 1 center dot 74 mmHg; 95% CI = 0 center dot 21-3 center dot 27). Analyses were associated with significant heterogeneity across studies. There were very few reported cardiovascular events (deaths, strokes, myocardial infarctions or venous thromboembolism), more commonly among MF individuals. Conclusions Very low quality evidence, downgraded due to methodological limitations of included studies, imprecision and heterogeneity, suggests that cross-sex hormone therapies increase serum triglycerides in MF and FM and have a trivial effect on HDL-cholesterol and systolic blood pressure in FM. Data about patient important outcomes are sparse and inconclusive.