Blood Test May Predict Preeclampsia
Protein Implicated in Life-Threatening Complication of Pregnancy
Karumanchi's study will be published next week in The New England Journal of Medicine but was released Thursday to coincide with his presentation of these findings at the annual meeting of the Society of Maternal-Fetal Medicine in New Orleans.
Last March, a study in the Journal of Clinical Investigation headed by Karumanchi first implicated rising levels of sFlt-1 as a possible cause of preeclampsia.
"We did a preliminary study on 20 women with preeclampsia and found that all had elevated levels," he tells WebMD. "And when we took that protein and injected it in rats, they all developed preeclampsia symptoms -- high blood pressure, protein spillage in urine, edema, and changes that led to blood vessel damage."
In the new study, his Harvard team joined NIH investigators in measuring sFlt-1 and PIGF levels in 240 women. "Essentially, in every case, sFlt-1 levels started to rise five to six weeks prior to the onset of symptoms in women who went on to develop preeclampsia -- and the higher the levels, the more severe their condition," says Karumanchi, of Beth Deaconess Medical Center. "They did not rise in women who didn't develop preeclampsia. That suggests these elevated protein levels are a cause -- rather than a consequence -- of the disease."
In a prepared statement, Duane Alexander, MD, director of the NIH's National Institute of Child Health and Human Development calls Karumanchi's findings "the most promising lead yet in the pursuit of a life-threatening disorder that has defied all attempts to prevent or cure it." Alexander was not involved in the study, but researchers at his agency were.
Still, in an accompanying editorial to Karumanchi's study, Caren G. Solomon, MD, MPH, and Ellen W. Seely, MD, of Brigham and Women's Hospital -- another Harvard-affiliated institution -- write that the results "are intriguing, but questions still remain." They indicate that other, undiscovered factors may likely have a more direct link to preeclampsia.