Menopause Hormone Therapy Shows No Association with Dementia Risk: New Review - Video

Hormone therapy after menopause doesn't raise dementia risk, according to the largest review ever conducted. A comprehensive meta-analysis commissioned by the World Health Organization (WHO), published in Healthy Longevity, examined over 1 million women's health records and found no strong evidence linking menopause hormone therapy (MHT, also called HRT) to higher or lower chances of dementia.

What is a meta-analysis? Unlike single studies, meta-analyses combine dozens of research projects using statistical methods to find true patterns and cancel out noise. They start with a clear question, systematically gather all relevant published studies, extract raw data, standardize results for fair comparison, and apply math models to reveal overall effects. This approach minimizes bias better than expert opinion alone while pooling enough data for reliable conclusions.

Why this matters for menopause: MHT replaces hormones like estrogen lost during menopause, dramatically easing hot flashes, night sweats, insomnia, low libido, and osteoporosis. Benefits usually outweigh small risks like slight blood clot increases for some women. But conflicting studies created confusion—did it help or hurt brain health long-term?

Researchers reviewed all available evidence, mostly observational studies tracking thousands of women over years. They analyzed different MHT types, doses, start ages, and formulas. Most showed weak, inconsistent links to dementia—some slightly positive, some negative—but all rated "low certainty" due to cause-and-effect limitations.

Key findings:

• No overall dementia risk increase from MHT

• One trial found estrogen-only MHT after age 65 added just 6.27 dementia cases per 1,000 women—clinically insignificant

• Results match 2024 Lancet Commission conclusions

• FDA recently dropped "black box" dementia warnings from MHT labels

Study limitations persist: most data were observational, MHT timing varied widely, and premature menopause cases (hysterectomy/oophorectomy) need more research.

Takeaway for women: MHT appears cognitively neutral when used properly for symptom relief. Benefits for quality of life—sleep, mood, bone health—remain clear. Discuss timing, personal risks, and delivery method (pills, patches, gels) with doctors.

REFERENCE: Melville, Melissa et al.; Menopause hormone therapy and risk of mild cognitive impairment or dementia: a systematic review and meta-analysis; The Lancet Healthy Longevity, Volume 6, Issue 12, 100803; DOI: 10.1016/j.lanhl.2025.100803