Toxaemia of Pregnancy and Risk of Mortality in Later Life: Evidence from the Royal College of General Practitioners' Oral Contraception Study

Abstract

Objective. To examine whether toxaemia of pregnancy is associated with an increased risk of mortality, in particular premature death. Methods. A cohort nested within the Royal College of General Practitioners' Oral Contraception Study focusing on women who never used oral contraceptives. A total of 2865 parous women with a history of toxaemia of pregnancy were compared with 11,460 parous women without such a history. Adjusted hazards ratios and 95% confidence intervals were calculated for death from all causes, vascular disease and cancer. Risk of premature death before the age of 65 years was compared between the two groups. Results. Women with a history of toxaemia had a significant increased risk of death from any cause (adjusted HR 1.20, 95% CI 1.04-1.39) and from vascular disease (adjusted HR 1.38, 95% CI 1.05-1.82). Women with a history of toxaemia who did not subsequently develop hypertension or vascular disease had significantly increased risks of all-cause and vascular mortality. These risks were not found among women who developed these conditions. Toxaemia of pregnancy was not associated with premature death. Conclusion. Toxaemia of pregnancy was associated with increased mortality but not premature death.

Keywords:

• Cardiovascular diseases
• Cohort
• Mortality
• Preeclampsia
• Women

ACKNOWLEDGMENTS

We thank Mrs. Val Angus for assembling the data set for the nested-cohort study, Mrs Aileen Murphy for other database administration support and Professor Amanda Lee for statistical advice. We also thank Dr Clifford Kay, who established and ran the study for its first 26 years and the many GPs who contributed data.

Declaration of Interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Funding

The OCS has received support from the Royal College of General Practitioners', Medical Research Council, Imperial Cancer Research Fund, British Heart Foundation, Schering AG, Schering Health Care Ltd., Wyeth Ayerst International Inc, Ortho-Cilag Pharmaceutical and Searle.

Table

Table