Postmenopausal women with a history of hormone therapy use were biologically younger compared with never-using counterparts, regardless of socioeconomic background, according to study results published in JAMA Network Open.
“We found that historical HT [use] was related to a slower biological aging pace, especially in postmenopausal women with disadvantaged socioeconomic status,” Chenglong Li, PhD, a postdoctoral fellow at the National Institute of Health Data Science at Peking University in Beijing, told Healio. “Moreover, we found the slower biological aging pace was more evident in postmenopausal women receiving hormone therapy after age 55 years or historically using HT for 4 to 8 years, supporting the hypothesis of appropriate timing of receiving HT.”
Li and colleagues conducted a population-based, retrospective cohort study using data from 117,763 postmenopausal women (mean age, 60.2 years) registered in the UK Biobank. At baseline, all participants completed a survey providing data on HT use and biological aging biomarkers from March 2006 to October 2010. Researchers assessed socioeconomic status by education, family income, occupation and the Townsend deprivation index.
Primary outcome was biological aging discrepancy assessed using validated phenotype age calculated through chronological age and nine biomarkers from baseline. Secondary outcomes included all-cause and cause-specific mortality.
Overall, 40.3% of postmenopausal women reported ever having used HT. Mean phenotypic age was 52.1 years for all postmenopausal women.
Current or past HT use was associated with 0.17 fewer years of aging discrepancy compared with never use (P < .001). This discrepancy was more apparent for women who initiated HT at age 55 years or older and for women who used HT for 4 to 8 years, with 0.32 and 0.25 fewer years of aging discrepancy, respectively.
Current or prior HT use was associated with a smaller aging discrepancy, regardless of socioeconomic status. However, the association between HT use and a smaller aging discrepancy was more apparent for women with low socioeconomic status. Researchers observed interactions for higher education and other education, with 0.08 and 0.23 fewer years of aging discrepancy, respectively (P= .02).
In addition, 12.7% of associations with all-cause mortality were explained by ties between HT use and phenotypic aging discrepancy. For cause-specific mortality, 19.3% of associations with CVD and 8.3% of associations with cancer mortality were explained by ties between HT use and phenotypic aging discrepancy.
“Due to the nature of observational study, we could not make formal conclusions about the causal relationships between HT and biological aging,” Li told Healio. “Further investigations capable of making causal inference, especially high-quality randomized controlled clinical trials, are needed to confirm our findings.”