Nighttime vasomotor symptoms (VMS) may be an indicator of Alzheimer disease (AD) in women, according to a recent study published in the American Journal of Obstetrics & Gynecology.
Takeaways
- Nighttime vasomotor symptoms (VMS) in women, such as hot flashes during sleep, may serve as a potential indicator of Alzheimer's disease (AD) risk, particularly when objectively measured.
- Understanding the connection between VMS and AD is crucial, given that 2/3 of AD patients are women.
- VMS have been linked to various physiological changes associated with AD, including alterations in brain function, metabolism, and cardiovascular health, potentially making them modifiable risk factors.
- A study conducted on women aged 45 to 67 years revealed that objectively measured VMS, especially during sleep, were significantly associated with reduced levels of certain plasma-based biomarkers linked to AD.
- These findings suggest that addressing sleep-related VMS could potentially mitigate AD risk, highlighting the importance of further research into the relationship between menopausal symptoms and cognitive decline in women.
Two-thirds of people with AD are women, making it vital to understand risk factors in this population. AD risk may be impacted by effects on the brain, metabolism, and cardiovascular system caused by sex hormones including changing estradiol during menopause.
VMS have been associated with memory performance, white matter hyperintensities, endothelial dysfunction, carotid atherosclerosis, brain function alterations, and resting-state functional connectivity. This indicates VMS as a potential modifiable risk factor for dementia and cognitive impairment.
Investigators conducted a study to evaluate the association between VMS and plasma-based biomarkers of AD. Participants included women aged 45 to 67 years with a uterus and at least 1 ovary who had late perimenopausal or postmenopausal status.
Recruitment occurred in the Allegheny County, Pennsylvania, community from 2017 to 2020. Assessments were performed through telephone and in-person screening procedures, medical history, questionnaires, physical measurements, fasting phlebotomy, and ambulatory VMS and sleep actigraphy monitoring.
Patients underwent VMS monitoring for 3 days using a physiological VMS monitor and VMS diary. The VMS monitor measured sternal skin conductance to determine VMS. The VMS diary included self-reported date-and-time-stamped VMS. VMS was divided by monitoring time and standardized to a 24-hour day to determine VMS rates.
AD plasma-based biomarkers included amyloid β (Aβ), phosphorylated tau, glial fibrillary acidic protein, and neurofilament light. A single-molecule array was used to measure these biomarkers. Covariates included race and ethnicity, educational attainment, head traumas, body mass index, genotypes, glucose and insulin levels, and sleep variables.
Participants were aged an average 59 years, with many being overweight and postmenopausal. An average 5 VMS per day were reported by ambulatory monitoring.
A significant reduction in Aβ42 and Aβ40 was associated with objectively measured VMS, especially sleep VMS. However, VMS was not significantly associated with other biomarkers of AD. Additionally, an association was not found between self-reported VMS and AD biomarkers.
A cluster characterized by low Aβ42 and Aβ40 and one characterized by high Aβ42 and Aβ40 were identified for the analysis. A significant association was also reported between more frequent sleep VMS and membership in the low Aβ42 and Aβ40 cluster, with an odds ratio of 1.18.
The associations between sleep and Aβ42 and Aβ40 remained when adjusting for endogenous estrogen, actigraphy assessed total sleep time, head trauma history, multivariable with head trauma, actigraphy-assessed wake after sleep onset, diabetes mellitus medications, and homeostatic model assessment scores.
These results indicated a potential association between VMS and AD biomarkers. Investigators concluded sleep VMS may be a modifiable risk factor for cognitive decline.
Reference
Thurston RC, Maki P, Chang Y, et al. Menopausal vasomotor symptoms and plasma Alzheimer disease biomarkers. Am J Obstet Gynecol. 2024;230:342.e1-8. doi:10.1016/j.ajog.2023.11.002
