Pregnancy‐Related Cardiometabolic Disease and Dementia Risk: A Twin Study

Abstract

AbstractBackgroundPregnancy related complications such as gestational diabetes mellitus (GDM) and pregnancy‐induced hypertension (PIH) have been shown to increase risk of cardiometabolic disease and may subsequently contribute to all cause dementia. While GDM and PIH have been genetically associated with their later life, non‐pregnancy related counterparts, it remains to be seen if these conditions independently contribute to dementia risk. This study investigated the degree to which GDM and PIH are genetically associated with dementia.MethodData were analyzed from 5,930 females in the Swedish Twin Registry who reported at least one pregnancy. Traditional twin analyses were conducted to determine the degree to which GDM and PIH are genetically influenced, as well as the degree of genetic and environmental overlap with the non‐pregnancy related variant of these conditions. Survival analyses examined relationships between 1) GDM and dementia and 2) PIH and dementia. Hypertension and diabetes outside of pregnancy were included in their respective models as covariates.ResultFor individuals who reported having been pregnant, risk of later life cardiometabolic risk factors were significantly increased if the similar conditions were experienced during pregnancy (P<.001). Both GDM and PIH showed evidence of significant familial associations, with a higher OR in MZ twins for both conditions (GDM OR = 6.74; 95% CI, 1.06 to 2.76; PIH OR = 8.27; 95% CI, 1.89 to 2.38). The survival models indicated that while neither pregnancy‐related condition was independently associated with dementia risk, diabetes outside of pregnancy was associated with a more than three‐fold increase in dementia risk (HR = 3.77, 95% CI = 1.17 – 1.63).ConclusionIn this large, population‐based cohort we found significant associations between pregnancy conditions and their respective cardiometabolic conditions. Cross‐twin associations further indicated that the association between pregnancy and non‐pregnancy cardiometabolic risk factors was driven by genetic influences. However, GDM and PIH did not appear to convey risk for dementia. These findings suggest that mechanisms driving diabetes and hypertension during pregnancy, while related to their later‐life counterparts, do not increase risk of neurocognitive decline.