Female hormone linked to all-cause mortality among elderly men
There appears to be a nonlinear relationship between total oestradiol (tE2) and free oestradiol (fE2) and all-cause mortality among older men, according to data from the Three-City cohort study. Specifically, the association is stronger for cardiovascular disease mortality and nonexistent for cancer mortality.
The Three-City cohort included 3,650 men aged ≥65 years who were followed for over 12 years for mortality. Baseline tE2 was measured, and fE2 was estimated using Vermeulen and Södergard algorithms. Oestrogen receptor (ER) was genotyped in a random subsample of 472 men without hormonal treatment.
Mortality data were drawn from death certificates. Inverse probability weighted Cox models were used to evaluate the association of oestradiol with all‐cause and cause‐specific mortality, and its interaction with ER genetic polymorphisms.
During the follow-up, 183 men died from CVD (n=44), cancer (n=57) or other causes (n=82). A quadratic relationship emerged between all‐cause mortality and tE2 and fE2 (p=0.04 and p=0.05, respectively). The risk of death was higher for the top and bottom tertiles compared to the middle one.
The association was pronounced for CVD mortality (p=0.01 for tE2; p=0.02 for fE2) and disappeared for cancer mortality. No evidence of an interaction between oestradiol and any ER polymorphisms on all‐cause mortality was observed.
Researchers cited several potential mechanisms underlying the association between endogenous oestradiol and CVD mortality. First, high or low endogenous oestradiol could be linked to a worse profile of traditional cardiovascular risk factors, including obesity, diabetes and hypercholesterolemia. Second, the possibility of the involvement of inflammation and hypercoagulability. Third, the association may partly reflect the role of testosterone, given that oestradiol and testosterone levels are correlated.
Although more studies are needed to elucidate the mechanisms, the results of the study could help improve the understanding of the role of oestradiol in men’s health, researchers said.