Maternal risk of ischaemic heart disease following elective and spontaneous pre-term delivery: retrospective cohort study of 750 350 singleton pregnancies

Hastie, C.E. , Smith, G.C., Mackay, D.F. and Pell, J.P. (2011) Maternal risk of ischaemic heart disease following elective and spontaneous pre-term delivery: retrospective cohort study of 750 350 singleton pregnancies. International Journal of Epidemiology, 40(4), pp. 914-919. (doi: 10.1093/ije/dyq270)

Abstract

<p><b>Background:</b> Previous studies have demonstrated an overall association between pre-term delivery and maternal risk of subsequent ischaemic heart disease (IHD). The underlying mechanism is unknown. We explored whether the association was specific to spontaneous or elective pre-term delivery.</p> <p><b>Methods:</b> We linked three Scottish routine data sources. The Scottish Morbidity Record 1 collects data on all acute hospital admissions, Scottish Morbidity Record 2 collects data on all pregnancies and Scotland's Registrar General collates data from all death certificates. Cox proportional hazards models were used to explore associations between pre-term delivery and subsequent IHD events (fatal and non-fatal) and IHD deaths. Analysis was restricted to women aged between 35 and 65 years at either the time of their first IHD event or at the end of follow-up.</p> <p><b>Results:</b> The cohort comprised 750 350 women who delivered a live, singleton infant following their first pregnancy. We demonstrated independent associations between pre-term delivery and IHD death [hazards ratio (HR) 2.26, 95% confidence interval (CI) 1.88-2.71] and total IHD events (HR 1.58, 95% CI 1.47-1.71). Associations were greater for elective than spontaneous pre-term delivery (P = 0.005). There was a trend whereby the association between pre-term delivery and IHD increased with decreasing age at first event.</p> <p><b>Conclusions:</b> We observed a stronger association between elective pre-term delivery and IHD, than spontaneous pre-term delivery and IHD. Elective pre-term delivery is usually undertaken because of growth restriction or pre-eclampsia, resulting from placental dysfunction. The age trend observed suggests an underlying genetic predisposition to both placental dysfunction and IHD.</p>

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Hastie, Dr Claire and Mackay, Professor Daniel and Pell, Professor Jill
• Authors: Hastie, C.E., Smith, G.C., Mackay, D.F., and Pell, J.P.
• Subjects: R Medicine > RA Public aspects of medicine
• College/School: College of Medical Veterinary and Life Sciences > School of Health & Wellbeing > Public Health; College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health
• Journal Name: International Journal of Epidemiology
• ISSN: 0300-5771
• Published Online: 01 February 2011