Preeclampsia Increases Risk of Early-Onset Dementia in Women: JAMA

Preeclampsia remains a significant concern for maternal and fetal health which affects close to 2% to 5% of pregnancies. Beyond its immediate impact, this disorder is now linked to long-term health risks, including an increased chance of cardiovascular and kidney diseases. A recent research published in the Journal of American Medical Association uncovered another consequence which was a threefold increased risk of late-onset vascular dementia 20 years post-pregnancy. This cohort study explored whether preeclampsia and other hypertensive disorders during pregnancy are also associated with an elevated risk of early-onset dementia.

The study utilized the Conception study, a nationwide prospective cohort study which drew data from the French National Health Insurance Information System. This comprehensive database included all deliveries in France after gestation of 22 weeks from January 1, 2010 to December 31, 2018. The study focused on individuals who were aged 30 years or older without a history of dementia by monitoring them from delivery until December 31, 2021. This research used crude and adjusted Cox proportional hazards regression models to calculate hazard ratios (HRs). These models treated exposures to hypertensive disorders of pregnancy (HDPs) as time-varying variables and adjusted for factors like obesity, diabetes, smoking, addiction and social deprivation.

The results found that, out of the 1,966,323 individuals (average maternal age 34.6 years), 128 developed dementia during a mean follow-up period of nine years. The individuals who developed young-onset dementia were generally older, more socially deprived, more likely to be smokers and more likely to have diabetes when compared to the individuals without dementia. The study found that preeclampsia significantly increased the risk of young-onset dementia (HR, 2.65). The risk was even higher when preeclampsia occurred before gestation of 34 weeks (HR, 4.15) or was superimposed on chronic hypertension (HR, 4.76). Also, severe preeclampsia was not linked to an increased risk of young-onset dementia.

These findings suggest a dose-dependent relationship between preeclampsia and early-onset dementia with higher risks linked to earlier onset and chronic conditions. While previous studies have associated preeclampsia with cognitive impairments and white matter lesions, this is the first to identify a direct link to early-onset dementia.

The outcomes of this study caution that their identification of dementia based solely on hospital diagnoses may have underestimated the true incidence. More studies are required to confirm these findings and to determine whether preeclampsia is an independent risk factor for dementia or if both conditions share common underlying risk factors.

Source:

Olié, V., Lailler, G., Torres, M. J., Regnault, N., Carcaillon-Bentata, L., & Blacher, J. (2024). Young-Onset Dementia Among Individuals With History of Preeclampsia. In JAMA Network Open (Vol. 7, Issue 5, p. e2412870). American Medical Association (AMA). https://doi.org/10.1001/jamanetworkopen.2024.12870