Menopausal HT does not increase risks for CVD, type 2 diabetes for middle-aged women
Menopausal hormone therapy does not affect risks for cardiovascular disease or type 2 diabetes, according to findings from a study of middle-aged postmenopausal women in South Korea published in Menopause.
“To our knowledge, this is the first nationwide population-based study that investigated the effects of menopausal HT on the risk of CVDs and type 2 diabetes among middle-aged postmenopausal women by considering the time-related bias,” Ji-Yeob Choi, PhD, associate professor in the department of biomedical sciences at Seoul National University Graduate School in South Korea, and colleagues wrote. “This study suggested that if baseline underlying diseases and years since menopause were assessed before starting therapy in postmenopausal women with menopausal symptoms, menopausal HT use does not expose them to the risks of CVD and type 2 diabetes.”
Researchers collected and analyzed data from the National Health Insurance Service database in South Korea from 2002 to 2016. Women in the database’s cancer-screening program who self-reported their menopause status between 2006 and 2008 and were aged 40 to 69 years at the onset of menopause were included in the study. Menopausal HT users were considered women who received HT prescriptions for at least 28 days during the study period. HT was classified as estrogen only, combined estrogen and progestogen, tibolone and multitype. Total prescription days were used to estimate cumulative duration of menopausal HT. Participants were followed until first reported CVD, type 2 diabetes, death or the end of the study period. Researchers developed a Cox regression model with a 1-year latency period after the first menopausal HT prescription to evaluate the risks for CVD and type 2 diabetes.
There were 58,060 postmenopausal women included in the analysis, with 8,013 in the HT user group and 50,047 in the nonusers group. After adjusting for covariates, menopausal HT was not associated with total CVD or type 2 diabetes. There were also no associations found with specific CVD outcomes. Duration of menopausal HT use and years since menopause had no effect on the risks for total CVD or type 2 diabetes. Differential effects by HT type were not observed for CVD, but women using multitype HT had an increased risk for type 2 diabetes (HR = 1.213; 95% CI, 1.015-1.448).
When the latency period length was changed, use of menopausal HT was associated with an increased risk for type 2 diabetes with no latency period (HR = 1.12; 95% CI, 1.02-1.23) and with a 6-month latency period (HR = 1.105; 95% CI, 1.004-1.217). No association was observed with a 1-year latency period.
“These results may reflect the ‘depletion of susceptible bias’ that an early increase caused by the initiation of exposure decreases with a longer duration of exposure,” the researchers wrote.
The researchers said the lack of increased risks for CVD and type 2 diabetes with menopausal HT may ease some concerns middle-aged women have with the use of HT.
“Although the protective effects of menopausal HT against CVD and type 2 diabetes were not observed, our results may contribute to reducing the current concerns of menopausal HT use among middle-aged postmenopausal women in Korea,” the researchers wrote.