In cases of preeclampsia, liver damage is a major concern. HELLP syndrome, a severe complication, occurs when the liver’s blood vessels constrict, leading to elevated liver enzymes and low platelet counts. This condition can cause life-threatening bleeding in mothers. Another critical condition related to preeclampsia is acute fatty liver of pregnancy (AFLP). Despite its name, AFLP is not a typical fatty liver but rather a severe form of liver failure that can be fatal.
While AFLP is rare in countries with low obesity rates among pregnant women, such as Japan, it is more common in nations where obesity is prevalent. In these regions, monitoring liver function is crucial because pregnancy can exacerbate liver disorders, leading to severe complications or even death.
Preeclampsia is often considered a “placental disease,” but it also affects other systemic organs, including the liver and adipose tissue. Routine antenatal check-ups typically include liver function tests to check for viral hepatitis and assess liver health. These tests sometimes predict preeclampsia, especially HELLP syndrome, in the latter part of pregnancy. However, they are not very effective at predicting the onset of preeclampsia early on.
Recent research by Liu et al. has explored the predictive value of affordable biochemical markers, including liver enzymes, in early pregnancy. Their study involved over 1,000 pregnant women and found that gamma-glutamyl transpeptidase (γ-GTP), alkaline phosphatase (ALP), and the ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) could predict preeclampsia. High levels of γ-GTP and ALP were strong indicators, while a higher AST/ALT ratio was linked to a lower risk. Additionally, the hepatic steatosis index (HSI), which combines liver enzyme levels with body mass index (BMI), was a good predictor, especially in women with high BMI.
The study revealed that HSI was particularly useful in predicting preeclampsia in obese pregnant women. However, it was less effective in non-obese women. Although γ-GTP was the only marker related to BMI, the researchers could not definitively say that obesity is the main cause of preeclampsia. Instead, they noted that preeclampsia is more common in obese women with abnormal liver enzymes.
Maternal obesity is already known as a risk factor for preeclampsia, and low-dose aspirin is used to reduce this risk. However, predicting high-risk pregnancies solely based on background factors is insufficient. To enhance prediction accuracy, new serum markers such as pregnancy-associated plasma protein-A (PAPP-A) and placental growth factor (PlGF), along with Doppler ultrasound of the uterine artery, are being utilized. These tests, though promising, are costly and require specialized equipment and training.
Routine biochemical tests, like liver enzyme measurements, are more accessible, even in resource-limited settings. Implementing these tests along with low-dose aspirin could be a practical strategy for preventing severe preeclampsia-related liver damage. This approach could be applied globally, but further research is needed to refine these strategies and understand the underlying mechanisms better.
Additionally, investigating how changes in these markers relate to the disease’s pathology is crucial. HELLP syndrome, a severe preeclampsia complication, is believed to result from liver damage due to placental debris, including soluble fms-like tyrosine kinase-1 (sFlt-1). However, the precise pathways linking these enzymatic changes to preeclampsia remain unclear. Understanding these relationships and exploring new treatment strategies, such as statin therapy, could offer more robust prevention methods.