Randomized Interventional Study on Prediction of Preeclampsia/Eclampsia in Women With Suspected Preeclampsia: INSPIRE.
Cerdeira AS., O'Sullivan J., Ohuma EO., Harrington D., Szafranski P., Black R., Mackillop L., Impey L., Greenwood C., James T., Smith I., Papageorghiou AT., Knight M., Vatish M.
The ratio of maternal serum sFlt-1 (soluble fms-like tyrosine kinase 1) to PlGF (placental growth factor) has been used retrospectively to rule out the occurrence of preeclampsia, a pregnancy hypertensive disorder, within 7 days in women presenting with clinical suspicion of preeclampsia. A prospective, interventional, parallel-group, randomized clinical trial evaluated the use of sFlt-1/PlGF ratio in women presenting with suspected preeclampsia. Women were assigned to reveal (sFlt-1/PlGF result known to clinicians) or nonreveal (result unknown) arms. A ratio cutoff of 38 was used to define low (≤38) and elevated risk (>38) of developing the condition in the subsequent week. The primary end point was hospitalization within 24 hours of the test. Secondary end points were development of preeclampsia and other adverse maternal-fetal outcomes. We recruited 370 women (186 reveal versus 184 nonreveal). Preeclampsia occurred in 85 women (23%). The number of admissions was not significantly different between groups (n=48 nonreveal versus n=60 reveal; P=0.192). The reveal trial arm admitted 100% of the cases that developed preeclampsia within 7 days, whereas the nonreveal admitted 83% (P=0.038). Use of the test yielded a sensitivity of 100% (95% CI, 85.8-100) and a negative predictive value of 100% (95% CI, 97.1-100) compared with a sensitivity of 83.3 (95% CI, 58.6-96.4) and negative predictive value of 97.8 (95% CI, 93.7-99.5) with clinical practice alone. Use of the sFlt-1/PlGF ratio significantly improved clinical precision without changing the admission rate. Clinical Trial Registration- URL: http://www.isrctn.com. Unique identifier: ISRCTN87470468.