Evaluation of serum calcium and serum magnesium in preeclampsia patients

 

 

Abstract               Aims and objective: Evaluation of serum calcium and serum magnesium status in preeclampsia patients. Material and methods: Study was conducted in Department of Biochemistry, in tertiary care centre, Mumbai. In this case-control study serum calcium and serum magnesium status was investigated in two groups: one with newly diagnosed cases of preeclampsia PE (n = 50) and the other of healthy primigravida as controls (n = 50) of same gestational age. Data was analyzed by Students Unpaired t test. Results demonstrated that difference for serum calcium between cases (mean 8.71 ± 0.57 mg/dl) and controls (mean 8.78 ± 0.28 mg/dl) was not significant. Difference for serum magnesium between cases (mean 2.02 ± 0.36 mg/dl) and controls (mean 2.01 ± 0.15 mg/dl) was also not significant. Differences for both parameters were not statistically significant (P value >0.05). Conclusion- we do not found significant difference in the Serum calcium and serum magnesium status in preeclampsia patients and normotensive controls.

Key Word: Serum calcium, serum magnesium, Preeclampsia.

 

 

INTRODUCTION

Pregnancy is a physiological state associated with many alterations in metabolic, biochemical, physiological, haematological and immunological processes. If there are no complications, all these changes are reversible following a few days to a few months after delivery^{1, 2}. Hypertensive disorders of pregnancy and their complications rank as one of the major cause of maternal mortality and morbidity in the world after obstetric haemorrhage, pre-existing medical disorders, sepsis and abortions^1,3. In addition, as it is strongly associated with foetal growth retardation and prematurity, it also contributes largely to perinatal mortality and morbidity^{1, 4}. Preeclampsia is a pregnancy specific syndrome and a leading cause of maternal and foetal morbidity and mortality. Preeclampsia is a multisystem disorder characterized by hypertension to the extent of 140/90 mm of Hg or more, proteinuria (≥ 300 mg/day) and edema induced by pregnancy after 20^th week.⁵ However preeclampsia is a complex multisystem syndrome and far more than gestational hypertension and proteinuria.⁶ Hypertensive disorders during pregnancy occur in women with pre-existing primary or secondary chronic hypertension, and in others who develop new-onset hypertension in the second half of pregnancy. Family history of essential hypertension is a risk factor in development of preeclampsia and there may also be relationship between preeclampsia and metabolic syndrome^{7, 8, 9}.The worldwide prevalence of preeclampsia is 9% and in India it is 8-10%. Preeclampsia is mainly a disease of primigravidas. The incidence is 14.1% in primigravidas versus 5.7% in multigravidas ^{7, 10}. In preeclampsia there is marked increase in response to vasopressin, norepinephrine, and to angiotensin. It is the increased responsiveness of the arterial systems to pressor substances which probably causes the generalized vasoconstriction and hypertension in preeclampsia⁷. Preeclamptic women shows decrease in serum calcium level. An increase in intracellular calcium in vascular smooth muscle cells during pregnancy is consistent with development of vasoconstriction and resultant hypertension.^11,12 The biochemical mechanism is presently unclear for this phenomenon.¹²

Hypomagnesemia in preeclmptic women is associated with haemodilution, renal clearance and increased mineral consumption by growing fetus.^13,14 Magnesium levels may have significant effects on cardiac excitability, vascular tone and contractility.^15,16,17 Since the calcium and magnesium contribute significantly in the functioning of the vascular smooth muscles, the present study was designed to evaluate their role in the preeclampsia.

 

MATERIAL AND METHODS

The study was conducted at the Department of Biochemistry, in a tertiary care centre hospital, after being approved by the Institutional Ethics committee. An informed consent was taken from all the participating women. Serum calcium and serum magnesium were investigated in two groups of pregnant women: one with preeclampsia PE (n = 50) and the other of healthy pregnant women (n =50). The second and third trimester primigravidae patients attending the obstetrics OPDs for routine follow up and patients from obstetrics ward were enrolled for the study. Subjects were grouped into two groups.

Inclusion Criteria: The Study group included primigravida patients > 20weeks gestation with proteinuria with BP ≥140/90mmHg and the Control group included primigravida women > 20weeks gestation normotensive and nonproteinuric. The common inclusion criteria for both groups were: singleton pregnancy, normal foetal morphology and the absence of concomitant disease and gestation between >20 and < 36 gestational weeks.

Exclusion Criteria: (For both the groups) Multiple Pregnancy, Previous History Of Abortion, Hypertension, Diabetes Mellitus, Cardiac illness, Gestational trophoblastic diseases, High grade fever or Any Concomitant illness. The fasting blood samples were collected in plain evacuated tubes. Samples were transferred to the laboratory where serum was separated and tests were performed. Serum calcium measured by O-Cresophthalein complexone method and serum magnesium was measured by calmagite EGTA method on Olympus AU400 Fully automated chemistry analyzer. Results of Preeclampsia (PE) group were compared with the results of control group of healthy pregnant women, matched for age and gestation.

Statistical analysis: For each parameter studied, mean and standard deviation was calculated to estimate the significance. The difference between the groups was measured by Students Unpaired‘t’ test. P Value less than 0.05 was considered as statistically significant. The calculations were performed using the statistical program SPSS for Windows Version 13, with a p value of < 0.05 considered significant.

RESULT AND DISCUSSION

The descriptive information of the study and control groups is as follows- Majority of subjects belonged to age group between 22-26 years. The period of gestation of all subjects was between 26-36 weeks. All the subjects in both the groups were primigravida patients. Our results demonstrated that difference in demographic characteristics between cases and controls was not statistically significant.

Figure 1: Comparison of Serum Calcium between Study and Control group

The serum Calcium levels were within reference range for both the groups. There was not much difference between mean values of both the groups. The difference was statistically non-significant.

 

Figure 4: Comparison of Serum Magnesium between Study and Control group

The serum Magnesium levels were within reference range for both the groups. There was not much difference between mean values of both the groups. The difference was statistically non-significant. Preeclampsia has been labelled as a dreaded disease affecting women and their pregnancy right from ancient times^1,18.,19. The numerous complications associated with it have triggered a phobia in pregnant women and aroused the interest of Obstetricians everywhere¹⁸. Preeclampsia is a pregnancy specific condition that increases maternal and infant morbidity and mortality^5,29. In our study, the patients had mean serum calcium value 8.71 ± 0.57 mg/dl and control group had 8.78 ± 0.28 mg/dl and statistical analysis showed that the difference was not significant. These findings are in agreement with studies by Standley CA et al²⁰, Sanders R et al²¹ and Vahid-Roodsari et al²². In all these studies there was no significant difference in Serum Calcium levels between preeclampsia patients and normal healthy pregnant controls. Interestingly studies by Kumru S et al²³, Sukonpan K et al²⁴, Punthumapol C et al²⁵, Seema Jain et al²⁶ Selina Akhtar et al²⁷, Sura Sagban et al²⁸, Indumati V et al³¹, Neeru Bhaskar et al²⁹, Pallavi P Chaurasia et al³⁰, Magna Manjareeka et al³² and Touhida Ahsan et al³³ found significantly decreased value of Serum Calcium in preeclampsia patients compared to normal pregnant women. This difference in observation of S. Calcium needs further investigation with higher sample size. Mean serum Magnesium in study group was 2.02 ± 0.36 mg/dl and in control group it was 2.01 ± 0.15 mg/dl. Statistical analysis showed that the difference was not significant. These findings are in accordance with the studies by Kumru S et al²³, Punthumapol C et al²⁵ and Neeru Bhaskar et al²⁹. They all concluded that there was no statistically significant difference in Serum Magnesium between preeclampsia patients and controls (normal pregnant women). Studies by Standley CA et al²⁰, Sukonpan K et al²⁴, Vahid-Roodsari et al²², Seema Jain et al²⁶, Indumati V et al³¹, Pallavi P Chaurasia et al³⁰ and Touhida Ahsan et al³³ concluded that there was significantly lowered Serum Magnesium in preeclampsia patients compared to normal pregnant controls. This difference in observation of S. Magnesium also needs further investigation with higher sample size.

 

CONCLUSION

we do not found any significant difference in serum calcium and serum magnesium levels in preeclampsia patients and normal controls. However we suggest further investigation with higher sample size.

 

REFERENCES

1. Amit D. Sonagra, Dattatreya. K, Jayaprakash Murthy D.S. Serum LDH, ALP and uric acid in hypertensive disorders of pregnancy. IJPBS |Volume 2, Issue 3, JULY-SEPT 2012, 201-209.
2. Maternal physiology. In : Cunningham F, Lenevo K, Bloom S, Hauth J, Gilstrap L, Wenstrom K (eds). Williams Obstetrics, 23rd edn. Mc Graw Hill, New York 2011, pp107-131. \
3. Park K. Preventative medicine in obstetrics, pediatrics and geriatrics. In: Park K. (eds). Park’s textbook of preventive and social medicine, 21st edn. M/s Banarasidas Bhanot publishers 2011, pp514-517.
4. Datta D. Hypertensive disorders in pregnancy. In: Konor H. ed. DC Datta’s Textbook of obstetrics. 7th ed. New Central book agency (P) Ltd, Kolkata 2011, pp219-240.
5. Noris M, Perico N, Remuzzi G. Mechanisms of Disease: pre-eclampsia Nature Clinical Practice Nephrology 2005; 1: 98-114.
6. Ness RB, Roberts JM. Heterogeneous causes constituting the single syndrome of preeclampsia: a hypothesis and its implications. American journal of Obstetrics and Gynaecology 1996;175:1365-70
7. Sunitha T, Sameera K, Umaramani G. Study of Biochemical changes in Preeclamptic women. International Journal of Biological and Medical Research. 2012; 3 (3): 2025-2028.
8. Packer CS. Biochemical markers and physiological parameters as indices for identifying patients at risk of developing preeclampsia. J. Hypertens.2005;23:(1) 45-6.
9. NAF Islam, MAR Chowdhury, GM Kibria, S. Akhter. Study of serum lipid profile in Preeclampsia and eclampsia. Faridpur Med. Coll. J. 2010;5(2):56-59.
10. Mordechai Hallak, David K James, Philip J Steer, Carl P Weiner, Bernard Ganik. High risk pregnancy: Management options 2^nd ed. 639 onwards, 2000.
11. Repke JT, Villar J. Pregnancy induced hypertension and low birth weight: the role of calcium. Am J Clin Nutr 1991; 54: 237-41.
12. Zemel MB et al. Altered platelet calcium metabolism as an early of increased peripheral vascular resistance and preeclamsia in urban black women. N Engl J Med 1990; 323: 434-38.
13. Kisters K, Barenbrock M et al. Membrane, intracellular and plasma magnesium and calcium concentrations in preeclamsia. Am J Obstet Hypertens 2000; 13: 756-59.
14. Williams KP, Galerneau F. The role of serum uric acid as prognostic indicator of maternal and fetal complications in hypertensive pregnancies. J Obstet Gyneco 2002; 24: 628-32.
15.  Sanders R, Konijnenberg A, Huijen H J et al. Intracellular and extracellular ionized uncomplicated pregnancy. Clin Chem lab Med 1999; 37: 55-9.
16. Tong GM, Rude RK. Magnesium deficiency in critical illness. J Intensive Care Med 2005; 20: 3-17.
17. Touzy RM. Role of Magnesium in pathogenesis of hypertension. Mol Aspects Med 2003; 24: 107-36.
18. Anjum K Sayyed, Alka B Sontakke. Electrolyte Status in Preeclampsia. Online International Interdisciplinary Research Journal, Volume-III, Issue-III, May-June 2013.
19.  Bell M. A Historical Overview of Preeclampsia-Eclampsia. J Obstet Gynecol Neonatal Nurs 39(5): 510–518, (2010).
20. .Standley CA, Whitty JE, Mason BA:Serum ionized magnesium levels in normal and preeclamptic gestation. Obstet Gynecol. 1997 Jan; 89(1):24-7.
21. Sanders R, Konijnenberg A: Intracellular and extracellular, ionized and total magnesium in Preeclampsia and uncomplicated pregnancy. Clin Chem Lab Med. 1999 Jan;37(1):55-9
22. Vahid-Roodsari, Fatemeh: Serum Calcium and Magnesium in Preeclamptic and Normal Pregnancies; A Comparative Study. J Reprod Infertil. 2008; 9(3):256-262.
23. Kumru S, Aydin S, Simsek M, Sahin K, Yaman M, Ay G: Comparison of serum copper, zinc, calcium, and magnesium levels in preeclamptic and healthy pregnant women. Biol Trace Elem Res. 2003 Aug; 94(2):105-12.
24. Sukonpan K, Phupong V. Serum calcium and serum magnesium in normal and preeclamptic pregnancy. Arch Gynecol Obstet. 2005 Nov;273(1):12-6
25. Chanvitya Punthumapol, Boonsri Kittichotpanich: Serum Calcium, Magnesium and Uric Acid in Preeclampsia and Normal Pregnancy. J Med Assoc; Thai Vol. 91 No. 7, 2008.
26. Jain S, Sharma P, Kulshreshtha S, Mohan G, Singh S. The Role of Calcium, Magnesium and Zinc in Preeclampsia. Biol Trace Elem Res 2009; 133:162-170.
27. Selina Akhtar1, Shelina Begum2, Sultana Ferdousi3. Calcium And Zinc Deficiency In Preeclamptic Women. J Bangladesh Soc Physiol. 2011 December; 6(2): 94-99.
28. Sura Sagban, Nada N. Al-Shawi The Effect of Orally –Administered Calcium Carbonate to Pregnant Women with Mild Preeclampsia. Iraqi J Pharm Sci, Vol. 20(1) 2011.
29. Neeru Bhaskar: Ionic changes in pre-eclamptic women: An overview. Journal of Advance Researches in Biological Sciences 07/2011; 3(1(a)):52-57.
30. Pallavi P Chaurasia: Changes in serum calcium and serum magnesium level in preeclamptic vs normal pregnancy IJBAR (2012) 03(06).
31. Indumati K, Kodliwadmath MV and Sheela MK. The Role of serum Electrolytes in Pregnancy induced hypertension. Journal of Clinical and Diagnostic Research 2011; 5(1): 66-69.
32. Magna manjareeka, sitikantha nanda. Serum electrolyte levels in preeclamptic women: a comparative study. IJPBS, Vol 3/Issue 2/April – June 2012.
33. Touhida Ahsan: Serum Trace Elements Levels in Preeclampsia and Eclampsia: Correlation with the Pregnancy Disorder Biological Trace Element Research June 2013, Volume 152, Issue 3, pp 327-332.