Hypertensive Disorders of Pregnancy: No Longer Just an "obstetrician's Disease".

We value the interest and discussion that our article has generated.1Brohan M.P. Daly F.P. Kelly L. et al.Hypertensive disorders of pregnancy and long-term risk of maternal stroke-a systematic review and meta-analysis.Am J Obstet Gynecol. 2023; 229: 248-268Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar We appreciate the insights of authors Olie and colleagues and wish to offer our response to their letter. Olie and colleagues suggest that the inclusion of hypertensive disorders of pregnancy (HDPs) in risk stratification models may add limited value for cardiovascular risk prediction based on existing evidence from the Norwegian HUNT Study.2Markovitz A.R. Stuart J.J. Horn J. et al.Does pregnancy complication history improve cardiovascular disease risk prediction? Findings from the HUNT study in Norway.Eur Heart J. 2019; 40: 1113-1120Crossref PubMed Scopus (91) Google Scholar This study indicated that the inclusion of preeclampsia in cardiovascular risk prediction models yielded limited improvements after taking traditional cardiovascular risk factors into account. However, we suggest the need for a cautious interpretation of these findings for the following reasons:1.This study had a median follow-up time of just 8.2 years, whereas existing longitudinal research suggests that HDPs may signal an increase in longer-term cardiovascular risk in women spanning decades.3Skjaerven R. Wilcox A.J. Klungsøyr K. et al.Cardiovascular mortality after pre-eclampsia in one child mothers: prospective, population based cohort study.BMJ. 2012; 345e7677Crossref PubMed Scopus (163) Google Scholar,4Leon L.J. McCarthy F.P. Direk K. et al.Preeclampsia and cardiovascular disease in a large UK pregnancy cohort of linked electronic health records: a CALIBER study.Circulation. 2019; 140: 1050-1060Crossref PubMed Scopus (167) Google Scholar2.The findings of the Norwegian HUNT Study represent a predominantly White population and may not be generalizable to all settings.5Jatta F. Sundby J. Vangen S. Lindskog B.V. Sørbye I.K. Owe K.M. Association between maternal origin, pre-pregnancy body mass index and caesarean section: a nation-wide registry study.Int J Environ Res Public Health. 2021; 18: 5938Crossref PubMed Scopus (8) Google Scholar3.Although existing studies have tended to focus predominantly on cardiovascular risk prediction models, there has been little published research on risk prediction models for either stroke or other endpoints, such as chronic kidney disease (CKD).6Barrett P.M. Khashan A.S. McCarthy F.P. Kublickiene K. Adverse pregnancy outcomes and maternal health: action needed for long-term benefit.Acta Obstet Gynecol Scand. 2020; 99: 1107-1109Crossref PubMed Scopus (4) Google Scholar4.If HDPs can add even modest improvements to risk prediction models in relative terms, this may still add value for disease prevention in absolute terms given that very large numbers of women are affected by HDPs. Olie and colleagues highlight that temporality is key to assessing patients' risk and that for any women who experience an HDP, their immediate risk of postpartum stroke is greater than women who remained normotensive in pregnancy. We agree with this assertion, but we do not believe that this affected our findings. As outlined in our Methods section, we excluded any studies where the outcome occurred <3 months after delivery.1Brohan M.P. Daly F.P. Kelly L. et al.Hypertensive disorders of pregnancy and long-term risk of maternal stroke-a systematic review and meta-analysis.Am J Obstet Gynecol. 2023; 229: 248-268Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar We fully agree with Olie and colleagues that the lack of detailed information on the role of key mediators remains an important gap in current knowledge. Associations between HDP and long-term risk of maternal stroke may be mediated by chronic hypertension, diabetes mellitus, or other factors.7de Havenon A. Delic A. Stulberg E. et al.Association of preeclampsia with incident stroke in later life among women in the Framingham Heart Study.JAMA Netw Open. 2021; 4e215077Crossref Scopus (20) Google Scholar Further research is required to better delineate causal mechanisms. This may inform whether future prevention efforts should focus on the primary prevention of self-resolving HDPs or the secondary prevention of potential post-pregnancy mediators. We agree that the greatest operational gain for women's cardiovascular health may arise from taking HDPs into account in the long-term assessment of cardiometabolic risk after the end of pregnancy. Knowledge levels for associations between HDP and cardiovascular disease, CKD, and stroke are suboptimal among affected women and healthcare professionals.6Barrett P.M. Khashan A.S. McCarthy F.P. Kublickiene K. Adverse pregnancy outcomes and maternal health: action needed for long-term benefit.Acta Obstet Gynecol Scand. 2020; 99: 1107-1109Crossref PubMed Scopus (4) Google Scholar,8Roth H. LeMarquand G. Henry A. Homer C. Assessing knowledge gaps of women and healthcare providers concerning cardiovascular risk after hypertensive disorders of pregnancy - a scoping review.Front Cardiovasc Med. 2019; 6: 178Crossref PubMed Scopus (47) Google Scholar However, HDPs cannot remain "an obstetrician's disease" if we want to harness this "window of opportunity" for chronic disease prevention. Concerted efforts are needed to improve knowledge levels on the increased risk of a range of chronic diseases for women affected by HDPs. Finally, we agree that robust evaluations will be required to monitor the effect of any health promotion initiatives that seek to optimize awareness of these associations. Earlier consideration of hypertensive disorders of pregnancy in women's life to reduce lifelong risk of strokeAmerican Journal of Obstetrics & GynecologyVol. 230Issue 3PreviewWe have read with interest the systematic review by Brohan et al1 about the increased long-term risk of maternal stroke in women who experienced a hypertensive disorder of pregnancy (HDP). Brohan et al1 suggest that their results advocate the integration of HDPs in the global cardiovascular risk stratification. Given recent results showing that adding preeclampsia history to an established prediction model of long-term cardiovascular risk leads to very modest improvements,2 we believe that this proposal could be challenged. Full-Text PDF