Acute Kidney Injury Common in Women Hospitalized With Preeclampsia

By Scott Baltic

November 01, 2019

NEW YORK (Reuters Health) - Pregnancy-related acute kidney injury (AKI) is seen in about 15% of women hospitalized with preeclampsia, according to a new study from South Africa.

More than half of the AKI cases were severe (stage 2 or 3), and AKI was associated with high rates of maternal and perinatal mortality, researchers report in Hypertension, online September 30.

The biggest risk factor for AKI was a history of hypertensive disorder in a previous pregnancy. Rates of maternal death, eclampsia, stroke, and stillbirth were all higher in women with AKI than in those without.

Clinicians working in middle-income settings should be aware of the significant likelihood of AKI in women presenting with preeclampsia and ensure prompt renal function testing, said Dr. Frances Conti-Ramsden of King’s College London, who worked on the study.

"Clinicians should take into account . . . that women who have experienced preeclampsia or another hypertensive disorder of pregnancy in a previous pregnancy are at higher risk of acute kidney injury," she told Reuters Health by email.

When AKI is diagnosed in women with preeclampsia, "this should alert clinicians to a higher risk of poor outcomes, including maternal and fetal death," Dr. Conti-Ramsden added. "In women with severe acute kidney injury, clinicians should consider delivering the baby promptly if appropriate."

Her team used data from the CRADLE 2 prospective observational study, which involved 1,547 women with preeclampsia admitted to any of three tertiary-care public hospitals in South Africa between 2015 and 2016.

More than one in seven participants (15.3%) had changes in serum creatinine consistent with Kidney Disease Improving Global Outcomes criteria for AKI. Among these individuals, 107 had stage-1 AKI, 67 had stage 2, and 63 had stage 3.

Women with any stage of AKI were significantly more likely to die, have an eclamptic seizure, have a stroke, or be admitted to intensive care, compared with women who did not develop AKI.

There were seven maternal deaths among women with AKI (3.0%), but no significant association with AKI stage. However, eclampsia rates did increase with AKI stage, as did rates of admission to the intensive-care unit.

Women who developed AKI were also significantly more likely to experience a stillbirth, and stillbirth rates rose significantly with increasing AKI severity. The perinatal mortality (including stillbirths) among offspring of women with AKI was 37.1%.

Of the 230 surviving women with AKI, 154 (67.0%) had recovered from AKI at discharge. This rate of renal recovery fell significantly with increasing stage of AKI: 90.5% of women with stage 1 AKI, 59.3% of women with stage 2, and 34.4% of those with stage 3.

Of the 37 women with creatinine concentrations assessed post-discharge, 31 (83.8%) had renal recovery and six (16.2%) did not; the six had all experienced stage 2 or 3 AKI.

Given the high rate of ongoing kidney impairment at discharge in women who had experienced preeclampsia-associated AKI, Dr. Conti-Ramsden said, "we recommend that these women are followed up with repeat renal function testing."

Dr. Line Malha, a nephrologist at Weill Cornell Medicine and NewYork-Presbyterian, in New York City, questioned whether the researchers were able to adjust for underlying kidney injury in the participants. "There are a lot of confounders in there," she told Reuters Health by phone.

She also noted that diagnosing preeclampsia is "a big issue" and that the authors had a clear definition for AKI, but not for preeclampsia. Still, she said, "I think this study is important. It will open a lot of eyes."

The study had no commercial funding, and the authors disclosed no conflicts of interest.


Hypertension 2019.