Preeclampsia linked to elevated risk of young-onset dementia

Preeclampsia is linked to increased young-onset dementia risk, according to a recent study in JAMA Network Open.¹

Takeaways

Preeclampsia, affecting 2% to 5% of pregnancies, has been associated with various adverse outcomes, including cardiovascular and kidney issues, with recent studies indicating a potential link to young-onset dementia.
The Conception study, based on data from the French National Health Insurance Information System, evaluated the impact of hypertensive disorders of pregnancy (HDPs), including preeclampsia, on long-term dementia risk among individuals aged 30 years and older without prior dementia history.
Findings revealed a significant increase in young-onset dementia risk among individuals with preeclampsia, particularly those with early-onset or superimposed chronic hypertension, highlighting a potential 3 to 4.7-fold higher risk compared to patients without HDPs.
Beyond young-onset dementia, additional research indicates an association between preeclampsia and various forms of dementia, including vascular dementia and Alzheimer's disease, suggesting a broader cognitive impact beyond the immediate postpartum period.
Researchers emphasize the need for more comprehensive studies to better understand and address this association.

Two percent to 5% of pregnancies are impacted by preeclampsia, which has been linked to multiple adverse outcomes impacting patients for decades following pregnancy. These include increased risks of cardiovascular and kidney morbidity and mortality.

Data has also indicated a potential 3-fold increased risk of late-onset vascular dementia a mean 20 years following pregnancy impacted by preeclampsia. To evaluate the impact of preeclampsia and other hypertensive disorders of pregnancy (HDPs) on long-term young-onset dementia risk, investigators conducted a cohort study.

The Conception study was assessed for relevant data, obtained from the French National Health Insurance Information System. All deliveries after 22 weeks’ gestation in France from January 1, 2010, to December 31, 2018, were included in the database.

Participants included individuals without a history of dementia aged 30 years or older. Follow-up occurred from delivery to December 31, 2021, with dementia risk calculated using hazard ratios (HRs) determined based on crude and adjusted Cox proportional hazard regression models.

HDP exposure was reported as a time-varying variable. Covariates included diabetes, obesity, drug or alcohol addition, tobacco use, and social deprivation.

There were 1,966,323 individuals with a mean maternal age of 34.6 years included in the analysis, 128 of whom presented with dementia. A primary diagnosis during hospitalization was used to determine dementia, and the mean follow-up period was 9 years.

An older maternal age was reported among individuals who developed young-onset dementia vs those who did not, of 36.4 years and 34.6 years, respectively. Additionally, smoking deprivation was reported in 13.3% and 12%, respectively, smoking in 14.8% and 9%, respectively, and diabetes in 2.3% and 0.7%, respectively.

The HR for young-onset dementia development among patients with preeclampsia was 2.65 when compared to patients without an HDP, indicating an increased risk. The risk increased further from preeclampsia before 34 weeks’ gestation and preeclampsia superimposed on chronic hypertension, with HRs of 4.15 and 4.76, respectively.

Additional data has also linked HDPs to subsequent maternal dementia.² A systematic review and meta-analysis was conducted to evaluate this association, including literature from the Web of Science, PubMed, Pyschinfo, and CINAHL databases.

HDPs evaluated included preeclampsia, eclampsia, chronic hypertension, gestational hypertension, and preeclampsia superimposed on chronic hypertension. Dementia was reported as the primary outcome, and cognitive impairment as the secondary outcome.

Title and abstract screening and data extraction were performed by 2 independent reviewers. Extracted data included year of publication, author, exposure and outcome definitions, study design, sample size, cofounders, and crude and adjusted estimates.

There were 25 studies included in the final analysis, including 175,132 women with an HDP and 2,326,541 with a normotensive pregnancy. Undifferentiated HDP was not significantly associated with all-cause dementia, with an adjusted HR (aHR) of 1.44.

Certain HDP subtypes were associated with any dementia, including preeclampsia with a pooled HR of 1.29. For vascular dementia, preeclampsia had an HR of 2.53. Preeclampsia was also linked to other cognitive impairments, with an aHR of 1.27 for Alzheimer’s disease.

This data supports the association between preeclampsia and dementia risk. Investigators recommended additional high-quality research to improve understanding about this association.