Age, menstruation history, and the brain

Area of Science:

• Neuroscience
• Reproductive Endocrinology
• Gerontology

Background:

• Menstruation history, including menopausal status and reproductive stage duration, may influence brain structure.
• Understanding these associations is crucial for identifying factors affecting cognitive aging.

Purpose of the Study:

• To investigate the cross-sectional association between menstruation history measures and brain volume.
• To explore how menopausal status, age at menopause, age at menarche, and reproductive stage duration relate to total brain volume (TBV) and hippocampal volumes (HV).

Main Methods:

• Utilized data from 5,072 UK Biobank women (aged 45-79), excluding specific medical histories (e.g., hysterectomy, hormone therapy, stroke).
• Employed multiple linear hierarchical regression models to analyze associations.
• Conducted sensitivity analyses using propensity score matching to compare premenopausal and postmenopausal women.

Main Results:

• Postmenopausal women exhibited larger TBV (1.06%) and HV (2.17%) than premenopausal women.
• Delayed age of menopause (after 45) was associated with smaller TBV and HV.
• Earlier age of menarche and longer reproductive stage duration were linked to smaller TBV.

Conclusions:

• Menopause may impact brain volume independently of typical aging processes.
• Early menarche, late menopause, and longer reproductive duration show negative associations with brain volume.
• The link between late menopause and reduced hippocampal volume warrants further investigation for dementia risk assessment.