Waist Circumference Measurement for Prediction of Preeclampsia: A Population-Based Cohort Study

BACKGROUND: Identifying women at high risk for preeclampsia is essential for the decision to start treatment with prophylactic aspirin. Prediction models have been developed for this purpose, and these typically incorporate body mass index (BMI). As waist circumference (WC) is a better predictor for metabolic and cardiovascular outcomes than BMI in nonpregnant populations, we aimed to investigate if WC is a BMI-independent predictor for preeclampsia and if the addition of WC to a prediction model for preeclampsia improves its performance. METHODS: We used a population-based cohort of 4,696 women with WC measurements taken in the first trimester. The influence of WC on the risk of developing preeclampsia was evaluated by multivariable logistic regression. We generated receiver operating characteristic curves and calculated the area under the curve (AUC) to evaluate the usefulness of WC measurements for prediction of preeclampsia. RESULTS: Women who developed preeclampsia had greater early pregnancy WC than women who did not (85.8 ± 12.6 vs. 82.3 ± 11.3 cm, P < 0.001). The risk of preeclampsia increased with larger WC in a multivariate model, adjusted odds ratio 1.02 (95% confidence interval 1.01–1.03). However, when adding BMI into the model, WC was not independently associated with preeclampsia. The AUC value for preeclampsia prediction with BMI and the above variables was 0.738 and remained unchanged with the addition of WC to the model. CONCLUSIONS: Large WC is associated with a higher risk of preeclampsia, but adding WC to a prediction model for preeclampsia that already includes BMI does not improve the model’s performance.