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Hormone replacement therapy and cognition: systematic review and meta-analysis
LeBlanc ES, Janowsky J, Chan BK, Nelson HD.. JAMA, 2001-03-01
Topic: Risk, prevention and care in population studies
Context Some observational data suggest that hormone replacement therapy (HRT) may reduce the risk of cognitive decline and dementia but results have been conflicting. Objective To review and evaluate studies of HRT for preventing cognitive decline and dementia in healthy postmenopausal women. Data sources Studies with English-language abstracts identified in MEDLINE (1966-August 2000), HealthSTAR (1975-August 2000, PsychINFO (1984-August 2000); Cochrane Library databases; and articles listed in reference lists of key articles. Study selection Randomized controlled trials and cohort studies were reviewed for the effects of HRT on cognitive decline; cohort and case-control studies were reviewed for dementia risk. No randomized controlled trials regarding dementia risk were identified. Data extraction Twenty-nine studies met inclusion criteria and were rated. Two reviewers rated study quality independently and 100% agreement was reached on Jadad scores and 80% agreement was reached on US Preventive Services Task Force quality scores. A final score was reached through consensus if reviewers disagreed. Data synthesis Studies of cognition were not combined quantitatively because of heterogeneous study design. Women symptomatic from menopause had improvements in verbal memory, vigilance, reasoning, and motor speed, but no enhancement of other cognitive functions. Generally, no benefits were observed in asymptomatic women. A meta-analysis of observational studies suggested that HRT was associated with a decreased risk of dementia (summary odds ratio, 0.66; 95% confidence interval, 0.53-0.82). However, possible biases and lack of control for potential confounders limit interpretation of these studies. Studies did not contain enough information to assess adequately the effects of progestin use, various estrogen preparations or doses, or duration of therapy. Conclusions In women with menopausal symptoms, HRT may have specific cognitive effects, and future studies should target these effects. The meta-analysis found a decreased risk of dementia in HRT users but most studies had important methodological limitations.
Key findings
- Context Some observational data suggest that hormone replacement therapy (HRT) may reduce the risk of cognitive decline and dementia but results have been conflicting.
- A meta-analysis of observational studies suggested that HRT was associated with a decreased risk of dementia (summary odds ratio, 0.66; 95% confidence interval, 0.53-0.82).
- The meta-analysis found a decreased risk of dementia in HRT users but most studies had important methodological limitations.
Why it matters
This review found that hormone replacement therapy did not help prevent cognitive decline in healthy postmenopausal women, though some observational studies suggested a lower dementia risk. The authors note most of those studies had important methodological limitations, so no clear prevention benefit is established.
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Study details
- Study designmeta-analysis
- Evidence strengthHigh
How this study scored 68/100
Published in a top-tier journal, and it is a meta-analysis pooling many studies. Scored zero for sample size, effect reported and studied in people because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 10 / 10 | Tier 1 — top-tier general journal (JAMA) |
| Journal's citation record | 4 / 4 | JAMA: journal h-index 1,011 (OpenAlex, 2026-10-29) |
| Study design | 12 / 12 | A meta-analysis pooling many studies |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2001 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | A review of other studies — randomisation is not credited here |
| Times cited | 6 / 7 | Cited 661 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 24.5 citations a year over 27 year(s) since 2001 |
| Impact for its field and year | 5 / 6 | Cited 34.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 20 other studies in this library |
| Still being cited | 2 / 4 | Cited 31 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 3 / 4 | Last-listed author Heidi D Nelson: h-index 60 (OpenAlex, whole career) |
| Institution's track record | 1 / 3 | Oregon Health & Science University: institution h-index 1,025 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 11255426) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 68 / 100 | — |
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Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
LeBlanc, E. S., Janowsky, J., Chan, B. K., & Nelson, H. D. (2001). Hormone replacement therapy and cognition: systematic review and meta-analysis. JAMA. https://doi.org/10.1001/jama.285.11.1489
Vancouver
LeBlanc ES, Janowsky J, Chan BK, Nelson HD. Hormone replacement therapy and cognition: systematic review and meta-analysis. JAMA. 2001. doi:10.1001/jama.285.11.1489. PMID: 11255426.
BibTeX
@article{leblanc2001-11255426,
author = {LeBlanc, E. S. and Janowsky, J. and Chan, B. K. and Nelson, H. D.},
title = {{Hormone replacement therapy and cognition: systematic review and meta-analysis}},
journal = {JAMA},
year = {2001},
doi = {10.1001/jama.285.11.1489},
pmid = {11255426},
url = {https://doi.org/10.1001/jama.285.11.1489}
}
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