— And you can’t avoid it, researcher warns
by Kristen Monaco, Staff Writer, MedPage Today June 4, 2020
Environmental exposure to certain synthetic chemicals was associated with early menopause, according to a new study.
In an analysis of over 1,100 premenopausal women, those who fell into the highest tertile for exposure to per- and polyfluoroalkyl substances (PFAS) — a family of endocrine-disrupting chemicals — were at a 63% higher risk for natural menopause, reported Ning Ding, PhD, MPH, of the University of Michigan School of Public Health in Ann Arbor, and colleagues.
As they noted in their study online in the Journal of Clinical Endocrinology & Metabolism, this equated to about a median 2-year earlier time to natural menopause — an onset age of 50.8 for those with high concentrations of exposure versus 52.8 for those with low concentrations.
When the data were broken down into 22 specific chemical types, women with the highest tertile of serum exposure of certain PFAS had a significantly higher risk for earlier natural menopause than women in the lowest tertile:
- N-23 perfluorooctane sulfonic acid (n-PFOS): HR 1.26 (95% CI 1.02-1.57, P for trend=0.03)
- Branched-24 PFOS: HR 1.27 (95% CI 1.01-1.59, P for trend=0.03)
- N-perfluorooctanoic acid: HR 1.31 (95% CI 1.04-1.65, P for trend=0.01)
However, perfluorohexane sulfonic acid concentrations were not significantly associated with the incidence of natural menopause, the researchers noted.
“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 the senior author of the study, Sung Kyun Park, ScD, MPH, co-director of the Occupational Epidemiology Program in the Center for Occupational Health and Safety Engineering at the University of Michigan School of Public Health, in a statement.
PFAS are most commonly found in everyday consumer household items like nonstick cookware, food packaging, furniture, insulation, and even drinking water, and because of their inability to break down, they’re often dubbed “forever chemicals.”
Several prior studies have tied PFAS exposure to several other adverse health outcomes and metabolic dysfunction, some of which include weight gain, trouble with weight maintenance, chronic kidney disease, and celiac disease.
“PFAS are everywhere. Once they enter the body, they don’t break down and build up over time,” Ding explained in a statement. “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 prospective cohort Study of Women’s Health Across the Nation (SWAN) included 1,120 ethnically diverse premenopausal women, ranging in age from 45 to 56. Natural menopause was defined as 12 months of amenorrhea without external causes like hysterectomy, bilateral oophorectomy, or hormone therapy. Of the 1,120 participants, 578 had a recorded date of natural final menstrual period.
The women were followed for 17 years, and serum concentrations of PFAS were quantified with high performance liquid chromatography-isotope dilution-tandem mass spectrometry. Tertiles of PFAS concentrations were split into four levels: low, low-medium, medium-high, and high.
One thing to bear in mind when it comes to PFAS exposure is to understand concentration patterns and mixtures of multiple PFAS, the researchers pointed out. “Results of mixture analyses showed a larger joint effect on ovarian aging compared with single PFAS.”
Study limitations, the researchers said, included that the first enrollment was at age 45, and therefore women who had an even earlier start of menopause before this age were excluded. In addition, the size of the cohort was drastically reduced due to the high rate of hormone therapy use.
“Due to PFAS widespread use and environmental persistence, their potential adverse effects remain a public health concern,” Ding and co-authors concluded.