SHBG levels inversely linked to hypertension in middle-aged adults

Levels of sex hormone-binding globulin (SHBG) show an inverse relationship with the development of hypertension and change in blood pressure (BP) levels, independent of major risk factors, according to a community-based study.

A total of 2,816 middle-aged participants were examined in this study, with a focus on cardiometabolic risk factors in 2002‒2005. A representative sample of 1,954 men and women was invited for a follow-up in 2012‒2014, while 1,327 participants were included in a second visit. Mean follow-up period was 9.7 years.

The researchers measured BP according to the guidelines set by the seventh Joint National Committee of Hypertension and recorded new cases of hypertension. They also measured SHBG at baseline. After excluding individuals treated with BP-lowering drugs, linear regression analyses and logistic regression analyses were performed to examine the association between SHBG, BP, and new hypertension cases.

At follow-up, the mean systolic and diastolic BPs were 123 and 72 mm Hg, respectively, and the corresponding mean increase from baseline was 5.8 and 2.9 mm Hg. Some 167 (16.1 percent) new cases of hypertension were identified during the follow-up period.

In the fully adjusted model, one standard deviation (SD) increase in SHBG at baseline inversely correlated with the risk of developing hypertension at follow-up (odds ratio, 0.74, 95 percent confidence interval [CI], 0.58‒0.95). After adjusting for covariates, one SD increase in SHBG correlated with a decrease in mean systolic BP (delta, ‒1.5 mm Hg, 95 percent CI, ‒2.2 to ‒0.8) and diastolic BP (delta, ‒1.0 mm Hg, 95 percent CI, ‒1.5 to ‒0.4).