Hormone replacement therapy and cognition: systematic review and meta-analysis

Area of Science:

• Neuroscience
• Endocrinology
• Gerontology

Background:

• Observational studies suggest hormone replacement therapy (HRT) may reduce cognitive decline and dementia risk.
• Conflicting results exist regarding HRT's impact on cognitive health in postmenopausal women.

Purpose of the Study:

• To systematically review and evaluate studies on HRT for preventing cognitive decline and dementia in healthy postmenopausal women.

Main Methods:

• Searched MEDLINE, HealthSTAR, PsychINFO, and Cochrane Library for relevant studies (1966-2000).
• Included randomized controlled trials and cohort studies for cognitive decline, and cohort/case-control studies for dementia risk.
• Assessed study quality using Jadad and US Preventive Services Task Force criteria.

Main Results:

• HRT improved specific cognitive functions (verbal memory, vigilance, reasoning, motor speed) in symptomatic menopausal women, but not asymptomatic women.
• A meta-analysis of observational studies indicated HRT use was associated with a reduced risk of dementia (OR, 0.66; 95% CI, 0.53-0.82).
• Methodological limitations, including potential biases and confounders, restrict the interpretation of dementia risk findings.

Conclusions:

• HRT may offer specific cognitive benefits for women experiencing menopausal symptoms.
• While observational data suggest a dementia risk reduction with HRT, significant methodological limitations necessitate cautious interpretation.
• Future research should focus on elucidating HRT's specific cognitive effects and addressing study design limitations.