Platelet Count-to-platelet Distribution Width Ratio and other Platelet Indices as Cost-effective Markers of Preeclampsia: a case control study.

Abstract

Background Platelet indices, like platelet count (PC), plateletcrite, mean platelet volume (MPV) and platelet distribution width (PDW), and their ratios have shown to be costeffective and better predictors of preeclampsia (PE). However, platelet count/platelet distribution width ratio was not studied. Objective To compare platelet indices and their ratios between pregnant women with and without predictors of preeclampsia. Method An analytical, comparative, case-control study. Two groups were compared; pregnant women with preeclampsia (case, n=24) and without preeclampsia (control, n=72). Multivariable linear regression analysis for hematological parameters was performed to assess the effect of gestational age. Logistic regression was performed to calculate odds ratio. Receiver operating characteristic curve was used to determine sensitivity, specificity and cutoff values. P < 0.05 was considered significant. Result There was statistically significant reduction in values of platelet count, plateletcrit, platelet count/mean platelet volume, and platelet count/platelet distribution width among the pregnant women with preeclampsia compared to control group, while significant increase was noticed in platelet distribution width and mean platelet volume. platelet count/platelet distribution width had the highest area under the curve (AUC) of 0.767, followed by platelet distribution width (AUC=0.752). At the cutoff of 15.1 (p<0.001) for platelet count/platelet distribution width, sensitivity was 70.8%, and specificity was 81.9%. The odds of diagnosing true positive cases of preeclampsia was 11.02 (95% CI =3.79-31.99, p=<0.001) times higher compared to values below it at this cutoff. Conclusion Platelet indices are economical tests that can act as indicators of risk of preeclampsia. Among these, platelet count/platelet distribution width has the highest sensitivity and specificity in the detection of preeclampsia at the cutoff of 15.1 and has emerged as better predictor of preeclampsia.