Adverse Pregnancy Outcomes Tied to Elevated Dementia Risk: Study Highlights Need for Early Monitoring

The researchers also observed that hypertensive disorders were linked to both all-cause and vascular dementia but not to Alzheimer’s disease. The findings were published online in The Lancet Healthy Longevity on December 12, 2024.

Individuals with adverse pregnancy outcomes face a higher risk of cerebrovascular disease; however, the link between such outcomes and cognitive impairment or dementia remains less clearly established. Therefore, Eliza C Miller, Department of Neurology, Columbia University, New York, NY, USA, and colleagues aimed to synthesize, combine, and evaluate the growing body of evidence exploring the associations between adverse pregnancy outcomes and mild cognitive impairment or dementia in parous women.

For this purpose, the researchers conducted a systematic review and meta-analysis of studies from PubMed, Web of Science, and Embase (up to July 18, 2024), focusing on women with adverse pregnancy outcomes (e.g., hypertensive disorders, gestational diabetes, stillbirth) and their risk of cognitive impairment or dementia. Studies involving men, nulliparous women, or cognitive impairment within six months of pregnancy were excluded. Eligible studies were screened, reviewed, and assessed independently by two investigators. The meta-analysis used random-effects models to pool adjusted hazard ratios (HRs) and confidence intervals (CIs).

The following were the key findings:

• A total of 11,251 publications were identified, with 15 studies (7,347,202 participants) meeting the inclusion criteria for the systematic review and eleven studies (6,263,431 participants) providing sufficient data for meta-analysis.
• Any adverse pregnancy outcome was linked to a higher risk of:
  • All-cause dementia (adjusted HR 1.32).
  • Alzheimer’s disease (HR 1.26).
  • Vascular dementia (HR 1.94).
• Hypertensive disorders of pregnancy were significantly associated with:
  • All-cause dementia (HR 1.32).
  • Vascular dementia (HR 1.78).
  • There is no significant association with Alzheimer’s disease (HR 1.24).
• Stillbirth was not significantly linked to a higher risk of all-cause dementia (HR 1.26).
• Preterm birth and fetal growth restriction showed similar effect directions in individual studies, but data were insufficient for meta-analysis.

"Women with a history of adverse pregnancy outcomes should be assessed for additional dementia risk factors and monitored for early signs of cognitive decline due to their elevated risk. To enhance the reliability of findings, future research should prioritize prospective and objective measurement of both exposures and outcomes," the researchers concluded.

Reference: https://www.thelancet.com/journals/lanhl/article/PIIS2666-7568(24)00186-7/fulltext