Study of Calcium to Creatinine Ratio in a Spot Sample of Urine for Early Prediction of Pre Eclampsia

Field: Medicine (Health Sciences)

INTRODUCTION:
Despite so much research and changes in management pre eclampsia is still a leading cause of maternal morbidity and mortality in India and worldwide. About 5-7% of the pregnancy are affected by pre eclampsia and hypertensive disorders. pre eclampsia is a multi system disorder pathology behind is reduced perfusion of organs due to vasospasm. It is usually associated with proteinuria or edema or both. This is the disorder of widespread vascular endothelial malfunction and vasospasm which occurs after 20 weeks of gestation and presents till 4-6 weeks postpartum.
AIMS AND OBJECTIVES:
To evaluate calcium to creatinine ratio for the early diagnosis of pre eclampsia and thus identify population at greater risk to be included in primary prevention programme.
Study Design:
Prospective study.
Study Population:
Women of gestatioal age < 20 weeks attending AN clinic in the Obstetrics and Gynaecology Department, Coimbatore Medical College Hospital, Coimbatore.
Study Period:
January 2018 to January 2019.
Sample Size: 200.
Selection Criteria:
INCLUSION CRITERIA:
Antenatal women of any age, Singleton pregnancy, Gestational age less than 20 weeks,
Any parity, Normotensive patients, Without proteinuria.
EXCLUSION CRITERIA:
•	Blood pressure 140/90mmhg or more.
•	Proteinuria –tested with dipstick >1+ in random urine sample
•	History of PIH in past pregnancy
•	History of chronic hypertension
•	Diabetes mellitus
•	Renal disease
•	Vascular disease
•	Immunological disease
METHODOLOGY:
All antenatal women who attended the outpatient department at the department
of obstetrics and gynaecology Coimbatore medical college hospital based on selection
criteria will be enrolled in this study.
1. Informed written consent will be obtained from all patients.
2. Participation in the study was voluntary.
3. All subjects were informed about the aims and objectives of the study, the test
to be done and the nature of their population.
4. A detailed history, a complete physical general examination and obstetric
examination was performed.
5. A spot urine sample was collected for estimation of calcium and creatinine.
6. Urinary Calcium was determined by orthocresophthalein method and urinary
creatinine by jaffes method.
7. CCR was calculated those with ratio <0.04 were considered positive those
with a ratio of >0.04 were considered as test negative.
8. Cutoff for CCR is taken as < 0.04.
9. Patients are then followed to predict how many of them developed pre eclampsia.
STATISTICAL ANALYSIS:
The results obtained were further analysed for SD, t test, SEM, and p value. The p value <0.001 was consider significant. comparative study was done by using chi square test.
RESULTS:
All 200 low risk antenatal patients were then followed till delivery once in four weeks to predict how many of them developed pre eclampsia. And the results obtained were analysed for statistical significance and if pre eclampsia developed managed as per local protocol.
Out of 200 samples, 19 women had positive calcium creatinine ratio while 181 had negative calcium creatinine ratio.
Among the 19 positive CCR ratio-
• 15 developed hypertension i,e 6 developed severe pre eclampsia, 5 developed non severe pre eclampsia and 4 developed gestational induced hypertension, while the remaining 4 women remains normotensive and No one developed eclampsia.
While among 181 negative CCR ratio ,one women developed gestational induced hypertension.
The incidence of preterm birth is more common than term birth in hypertension of pregnancy and it is about more than 40%. In our study also when comparing the association of gestational age at delivery with CCR, premature deliveries is more than term deliveries in women those who developed hypertension during pregnancy and it showed p value of 0.000* and it is statistically significant.
In our study we compared the association of gestational age of collection with CCR,
• First trimester (14 weeks)-69 had negative CCR and 3 of them had positive CCR.
• Second trimester(14-20 weeks)-112 had negative CCR and 16 had positive CCR.
While comparing the association of gestational age of collection with CCR had p value of 0.046 and it is statistically significant. And the second trimester CCR (84%) is more ideal than first trimester(15%) CCR.
The association of PIH with CCR in primigravida and multigravida is also statistically significant with significant p value of 0.000*. The incidence of positive CCR in primi and multi in our study is about 11% and 5% respectively, which is as similar as incidence of PIH in primi and multi and its about 10-15% and 5% respectively.
CONCLUSION:
The estimation of Calcium Creatinine Ratio in a spot sample of urine for prediction of pre eclampsia had p value of < 0.001 and it is statistically significant and it can be used as a screening test for low risk asymptomatic antenatal women with less than 20 weeks of gestation for prediction of pre eclampsia.
Also the association of gestational age of collection less than 20 weeks with CCR, has a significance p value and it is also statistically significant and while comparing second trimester CCR is more ideal than first trimester.
The association of PIH with CCR in primigravida and multigravida is also statistically significant with significant p value of 0.000*.
It can therefore be suggested as a screening test for low risk antenatal women with less than 20 weeks of gestation for prediction of pre eclampsia, especially when the government encourages in booking visit.
As PICME (Pregnancy and Infant Cohort Monitoring and Evaluation) entry should be made before 12 weeks as per government norms, so we can have the opportunity to screen the mother with this CCR ratio at earlier period to predict pre-eclampsia during this booking visit.
And also PMSMA-The Pradhan Mantri Surakshit Matritva Abhiyan under ministry of health and family welfare guarantees an antenatal care free of cost universally to all pregnant women in their second and third trimesters of pregnancy on the 9th of every month.
We can also screen the mother with this CCR ratio to predict the pre eclampsia as a part of this government schemes.
Pre eclampsia is a chief cause for maternal morbidity and mortality in worldwide, especially in developing countries. Many research work are going on for a better predictor for pre eclampsia and therefore to prevent the maternal mortality and mortality associated with that.
An accessibility of a good screening test would pledge and encourage more exploration work in the direction of secondary prevention of early diagnosis and treatment.