A study of 1,120 midlife women in a 17-year-long prospective cohort study found that women with high PFAS levels in their blood reached menopause two years earlier than those with lower levels.
Known as 'forever chemicals,' PFAS are human-made and used in a wide variety of non-stick and waterproof products and firefighting foams. PFAS chemicals can contaminate drinking water, and it has been estimated that 110m Americans (one out of three) may consume drinking water contaminated with these chemicals.
"PFAS are everywhere. Once they enter the body, they don't break down and build up over time," said the study's lead author Dr Ning Ding, of the University of Michigan School of Public Health in Ann Arbor, Michigan. "Because of their persistence in humans and potentially detrimental effects on ovarian function, it is important to raise awareness of this issue and reduce exposure to these chemicals."
The researchers studied 1,120 midlife women from the Study of Women's Health Across the Nation, a 17-year-long prospective cohort study. They found that women with high PFAS levels in their blood samples reached menopause two years earlier than those with lower levels.
"Even menopause a few years earlier than usual could have a significant impact on cardiovascular and bone health, quality of life, and overall health in general among women," said corresponding author Dr Sung Kyun Park, of the University of Michigan School of Public Health.
Abstract
Context: Previous epidemiologic studies of per- and polyfluoroalkyl substances (PFAS) and menopausal timing conducted in cross-sectional settings were limited by reverse causation because PFAS serum concentrations increase after menopause.
Objectives: To investigate associations between perfluoroalkyl substances and incident natural menopause.
Design and Setting: A prospective cohort of midlife women, the Study of Women’s Health Across the Nation, 1999-2017.
Participants: 1120 multi-racial/ethnic premenopausal women aged 45-56 years.
Methods: Serum concentrations of perfluoroalkyls were quantified by high performance liquid chromatography-isotope dilution-tandem mass spectrometry. Natural menopause was defined as the bleeding episode prior to at least 12 months of amenorrhea not due to surgery or hormone use. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).
Results: Participants contributed 5466 person-years of follow-up, and 578 had incident natural menopause. Compared to the lowest tertile, women at the highest tertile of baseline serum concentrations had adjusted HR for natural menopause of 1.26 (95%CI: 1.02-1.57) for n-perfluorooctane sulfonic acid (n-PFOS) (Ptrend=0.03), 1.27 (95%CI: 1.01-1.59) for branched-PFOS (Ptrend=0.03), and 1.31 (95%CI: 1.04-1.65) for n-perfluorooctanoic acid (Ptrend=0.01). Women were classified into four clusters based on their overall PFAS concentrations as mixtures: low, low-medium, medium-high, and high. Compared to the low cluster, the high cluster had a HR of 1.63 (95% CI: 1.08-2.45), which is equivalent to 2.0 years earlier median time to natural menopause.
Conclusion: This study suggests that select PFAS serum concentrations are associated with earlier natural menopause, a risk factor for adverse health outcomes in later life.
Authors
Sung Kyun Park, Ellen B Gold, Stuart Batterman, Bhramar Mukherjee, Antonia M Calafat, John F Randolph, Siobán D Harlow, Ning Ding
[link url="https://www.sciencedaily.com/releases/2020/06/200603100443.htm"]The Endocrine Society material[/link]
[link url="https://academic.oup.com/jcem/advance-article-abstract/doi/10.1210/clinem/dgaa303/5848088?redirectedFrom=fulltext"]The Journal of Clinical Endocrinology & Metabolism abstract[/link]