Background:
The ratio of soluble fms-like tyrosine kinase 1 (sFlt1) to placental growth factor (PIGF) (sFlt-1/PIGF) is a validated biomarker for short-term prediction of pre-eclampsia (PET) risk. Currently the evidence supporting retesting SFlt-1/PIGF ratio is low, however emerging evidence suggests an association between rate of change, and risk of PET and shorter latency to delivery.[1-2]
Aim:
To assess whether the rate of change in sFlt-1/PlGF ratio per day (delta) is associated with shorter latency to delivery and occurrence of PET.
Methods:
A retrospective cohort study was conducted on all women undergoing at least two sFlt-1/PlGF tests at a single tertiary centre in Australia between 2021 and 2024 (n = 171).
Results:
Overall, no significant correlation was found between delta and latency to delivery (r= 0.0253, p=0.746). Mean delta was not significantly higher in women who developed PET (2.03 vs -5.51, 95% CI -3.37 – 18.66, p=0.171). When stratified by initial test result, the subgroup with an initial normal test was observed to have a significant correlation between delta and latency to delivery (r = -0.202, p=0.047). Within this subgroup, mean delta was also significantly higher in women who developed PET (0.62 vs 1.42, 95% CI 0.19 – 1.42, p-0.01). In the initial abnormal test subgroup, there was no significant association.
Conclusion:
In women with an initial normal sFlt-1/PIGF ratio, the delta was significantly associated with shorter latency to delivery and PET development. These findings support delta sFlt-1/PlGF as a potential prognostic marker in this subgroup, warranting further investigation.