Objective: To systematically review and summarize studies investigating an association between a history of preeclampsia and cognitive function later in life.
Data sources: Studies published before August 2017 were identified without any language restriction or study design limits through electronic searches of 10 main databases including MEDLINE and ClinicalTrials.gov.
Methods of study selection: We considered all observational studies that included preeclampsia as a clearly defined prespecified risk factor and that examined a cognition-related outcome measure including validated cognitive tests, magnetic resonance brain imaging, or a clinical diagnosis of dementia. Study quality was assessed using the New-Castle Ottawa scale. All review stages were conducted independently by two reviewers, and disagreement was resolved by a third reviewer. Where possible, data were pooled using a random-effects model.
Tabulation, integration, and results: Of 3,126 potentially relevant studies, 13 were included in our review (1,314 women with prior preeclampsia and 289,080 women with prior normotensive pregnancy); median time since pregnancy was 6 years. A higher number of self-reported deficits in perception, memory, and motor functioning on the Cognitive Failure Questionnaire was reported in women with vs without prior preeclamptic pregnancies (Cognitive Failure Questionnaire mean total score 41.5 vs 36.8 out of 100, weighted mean difference of -5.1 points [-9.4 to -0.8]). Our meta-analysis did not reveal significant differences in studies assessing attention (Digit Symbol Substitution or Coding); however, women with preeclampsia performed worse on one of two meta-analyzed tests assessing memory (Letter Number Sequencing mean total score: 10.6 vs 10.1 out of 21, weighted mean difference of 0.63 points 0.06-1.2). Pooling of cognitive outcome measures for studies assessing brain imaging or a clinical diagnosis of dementia were limited by differences in reporting and marked heterogeneity between studies.
Conclusion: Although preeclampsia is associated with subjective cognitive symptoms, our systematic review did not demonstrate clear evidence of impairment on standard neurocognitive tests. There is a paucity of high-quality studies assessing cognitive outcomes after preeclampsia.