1218 Predicting hypertensive disorders of pregnancy
Preeclampsia and cardiovascular disease have several underlying risk factors that are common to the two conditions: obesity, insulin resistance, dyslipidaemia, endothelial dysfunction and inflammation. Furthermore, the second half of pregnancy is notable for progressive insulin resistance, hyperinsulinaemia, hyperlipidaemia and increasing inflammatory markers. This would seem to set the stage and predispose pregnant women to the ravages of pregnancy-related hypertensive disorders such as preeclampsia (a multisystem condition characterised by systemic maternal inflammation, endothelial dysfunction and insulin resistance). Perhaps one way to address the interplay would be to question why pregnancy-related hypertension is not more common given that pregnancy is characterised by metabolic and inflammatory risk for elevated blood pressure, but the other is to track metabolic and inflammatory markers to predict future hypertension. Such an investigation was carried out by researchers at Kaiser Permanente in California who followed up women participating in a comprehensive multiphasic health examination programme between 1984 and 1996. The cohort consisted of 3380 women, with 205 subsequently diagnosed with a hypertensive disorder of pregnancy (80 gestational hypertension, 106 preeclampsia or eclampsia, 19 both). Any subjects with any form of hypertension prior to the pregnancy were excluded from the analysis. Risk factors that were considered and measured included serum glucose, cholesterol, leucocyte count, blood pressures (systolic and diastolic), BMI, pre-hypertension (systolic >120 and/or diastolic ≥80mmHg). The outcome of interest was pregnancy-related hypertension in a subsequent pregnancy. On average the pre-pregnancy assessment of risk was carried out 4.6 years before delivery. A fully-adjusted multivariate model containing all pre-gravid cardiometabolic and inflammatory risk factors found that pre-hypertension, obesity (BMI≥25kg/m2) and leucocyte count ≥7.2/cu.mm were independently associated with increased risk for a hypertensive disorder of pregnancy (respective odds ratios of 2.1, 1.6 and 1.6). The risk also increased with the number of risk factors present, with the joint effects of BMI ≥25 and pre-hypertension resulting in a 3.5-fold increased risk for a hypertensive disorder of pregnancy. The study is important in light of the fact that preeclampsia and other pregnancy-related hypertensive disorders are the leading contributors to perinatal morbidity and mortality worldwide, and being forewarned might result in better outcomes for both mother and child.
Am J Obstet Gynecol 2012; doi: 10.1016/j.ajog.2012.05.017
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