Lipid profile in second trimester of pregnancy as a predictor of preeclampsia in patients attending antenatal clinic in Kilpauk Medical College and Hospital: A prospective cohort study

INTRODUCTION: Hypertensive disorders of pregnancy complicates around 5-10% of all pregnancies. It is one of the common causes of maternal & perinatal morbidity and mortality. How pregnancy initiates the rise in blood pressure or aggravates hypertension still remains an enigma inspite of research for many decades and it still remains one among the most significant and unsolved problems in obstetrics. Studies state that abnormal placentation and endothelial dysfunction are the key factors in the development of preeclampsia. Several markers have been investigated as the predictors of pre-eclampsia. Lipid levels in early pregnancy can be a good predictor of development of pre-eclampsia in patients. Dyslipidemia in early pregnancy leads to more oxidative stress by the formation of lipid peroxides and reactive oxygen species, thus predisposing to the development of pre-eclampsia. According to WHO even in developed countries, preeclampsia accounts for 16% of maternal mortality (Khan & Colleagues 2009). For every case of maternal death there are ten near miss cases. Such is the magnitude of this multi system disorder. Berg & colleagues (2005) stated that around 50% of these preeclampsia related deaths are preventable. Thus early identification of pregnancies at risk may enhance the development of new strategies for antenatal monitoring, to detect disease earlier and intervene appropriately to improve maternal and perinatal outcome. AIM OF THE STUDY: To study whether abnormal lipid profile in the second trimester of pregnancy can be a predictor of pre-eclampsia. MATERIALS AND METHODS: Study Design: Prospective Cohort Study. Study Period: Between Oct 2010 to Mar 2012. Place of Study: Antenatal Clinic, Department of Obstetrics & Gynaecology, Kilpauk Medical College and Hospital. Inclusion Criteria: 1. Pregnant women with singleton pregnancy, 2. With LMP & USG confirmed pregnancy between 17-19 weeks of gestation. Exclusion Criteria: 1. Diabetes mellitus, 2. Chronic hypertension, 3. Renal disorder, 4. Hypothyroidism, 5. Family/personal history of dyslipidemia, 6. On Any medications except for vitamins & minerals, 7. Ultra sound proved congenital anamolies, 8. PCOS. METHODOLOGY: A total of 129 antenatal patients who attended the antenatal clinic of the Department of Obstetrics & Gyncecology, Govt. Kilpauk Medical College, were selected based on the inclusion & exclusion criteria after obtaining their informed consent. All selected women were subjected to a detailed history taking comprising of age, parity, prepregnant body weight, medication history, family history, medical history, detailed obstetric history including previous history of preeclampsia. Then they were subjected to clinical examination and routine laboratory investigations were carried out on the first day. Fasting blood samples (4ml) were collected from these patients on the next day and subjected to lipid profile analysis. Total Cholesterol, HDL, TGL levels were estimated and the levels of LDL and VLDL were calculated indirectly. These patients were regularly followed up in the antenatal op till their delivery once in every two weeks and a thorough clinical examination was carried with special focus on blood pressure and urine albumin. All the details were entered. RESULTS OF THE STUDY: The patients who developed pre-eclampsia were grouped as preeclampsia cohort. And the rest of the patients who remained normotensive till delivery were grouped as normal cohort. The factors taken for analysis were age distribution, obstetric score, Body Mass Index, history of preeclampsia in previous pregnancy, and the components of lipid profile. Mean + SD of all variables of interest were determined for preeclampsia cohort and for normal cohort separately and difference was tested by t test. The predictive values of the individual components of lipid profile were analysed using ROC curve. Logistic regression model was used to estimate the causal effect of each predisposing factor on outcome and to find out the most effective predictor. CONCLUSION: After analysing and comparing the results between the preeclampsia cohort and normal cohort it was concluded that • The pre-pregnant BMI was higher among the patients who developed preeclampsia than normotensive counterparts. • The study cohort had a higher Total cholesterol, Triglyceride, Low density Lipoprotein, Very Low Density Lipoprotein levels. • The preeclampsia cohort also had a lower HDL level. • Thus there exists a positive correlation between dyslipidemia and development of preeclampsia. • Therefore abnormal lipid profile before 20 weeks is a very good predictor of preeclampsia development. Thus it may be concluded that, detecting dyslipidemia before 20 weeks of gestation would help us to recognise pregnancies at high risk for preeclampsia even before the clinical syndrome. Early recognition ,would help us in offering better surveillance to detect and treat the disease earlier for a better maternal and perinatal outcome. Given that the raised triglyceridemia as a feature of the insulin resistance syndrome; interventional studies are required to find out whether pre-pregnancy weight reduction can lower the risk of preeclampsia. The determination of insulin levels, inflammatory markers in early pregnancy and then followed by a thorough assessment of the outcome through a large cohort study, may help in addressing the role of metabolic syndrome in causation of preeclampsia.