Comparison of haematological and biochemical ...

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Journal of Obstetrics and Gynaecology, 2014; Early Online: 1–4 © 2014 Informa UK, Ltd. ISSN 0144-3615 print/ISSN 1364-6893 online DOI: 10.3109/01443615.2014.948817

Comparison of haematological and biochemical changes between non-anaemic and anaemic primigravid women in a north Indian population to establish normative values H. Shankar1, N. Kumar2, D. N. Rao1, N. Chandhiok2, R. Sandhir3, A. Kriplani1, L. Dhaliwal4, R. Sehgal1, V. L. Jindal1, L. Maithi1, S. Kandpal1, A. Kumar1 & S. Kurra1 1All India Institute of Medical Sciences, Ansari Nagar, 2Indian Council of Medical Research, Ansari Nagar, New Delhi, 3Panjab University and

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4Postgraduate Institute of Medical Education & Research, Chandigarh, India­

Pregnancy is accompanied by several haemodynamic, biochemical and haematological changes, which may lead to severe problems, if they are not suitably addressed. The current study highlights the haematological and biochemical differences observed in anaemic (AP) and non-anaemic primigravida (NAP), at their 2nd trimester, in a north Indian population. There were significant differences (p  0.05) in the body weight and body temperature of NAP compared with AP. A significant decrease (p  0.001) in haematological parameters including haemoglobin, haematocrit, erythrocyte count, MCH and MCHC, was observed in AP; however, MCV was found significantly higher (p  0.038). Many biochemical parameters viz. potassium, albumin, total protein and calcium levels were significantly reduced (p  0.01) in AP, except alkaline phosphatase whose level was found significantly increased (p  0.01). The findings of the study suggest that haematological and biochemical changes take place in anaemia during pregnancy. Further, the results obtained shall be used for establishing normative values for similar populations. Keywords: Anaemia, biochemical changes, haematological parameters, normative values, pregnancy

Introduction Pregnancy is a state where haematological and biochemical alteration takes place as a function of physiological adaptation of the body. A routinely used haematological test reveals the general health of the body and is widely used during pregnancy, as it is the most reliable, quick and cost-effective test (Shen et al. 2010). One of the most studied haematological indices include haemoglobin (Hb) concentration, and low Hb (Hb  11.0 g/dl), referred as anaemia, is a widely recognised haematological abnormality (CDC 1998). According to the World Health Organization, anaemia during pregnancy is a common and serious problem (Reveiz et al. 2007) which needs to be addressed carefully. Anaemia is still a cause of considerable perinatal morbidity and mortality and is highly prevalent in South Asian countries; India being highest among them (Kalaivani 2009). Furthermore, nearly half of the maternal deaths due to anaemia occur in South Asian nations;

India contributes to about 80% of these maternal deaths (Ezzati et al. 2002). Maternal and child health is still a prevalent issue of public health in South-east Asian countries, which directly contributes to the development of any community. As this group is most vulnerable to environmental factors and various disease-related sickness and death; it is a national priority to run various pregnancy protection programmes to overcome this dire problem. Various strategies and national policies have been laid down by India and are currently being adopted (Government of India 2013) to overcome anaemia, but the situation is still overwhelming. The possible reasons behind this scenario are multifactorial and include iron, folate and B12 deficiency (Kalaivani 2009); low iron intake in the diet; low bioavailability of supplemented iron; infections associated with malaria and hookworm infestations (National Nutrition Monitoring Bureau (NNMB) 2003; Toteja and Singh 2004); the scarcity of iron supply; vomiting and constipation symptoms associated with iron intake, all of which hamper the frequency/regularity of iron intake (Schultink et  al. 1993). Thus, along with emphasising the role of the abovementioned factors in anaemia, careful monitoring of haematological and biochemical parameters might help to improve the current situation. Since the obtained values were derived from local inhabitants having a similar ethnicity, race, lifestyle, environmental set-up, these findings are useful for establishing reference values for the particular region. The current study was thus aimed to assess the status of haematological and biochemical changes along with anthropometric parameters in non-anaemic (NAP) and anaemic primigravid (AP) women and to contribute in establishing the normative values in this north Indian population.

Material and methods A total of 520 primigravid women between the ages of 19 and 30 years, and at 13–16 weeks’ gestation, were recruited on their first visit to the antenatal clinic at the Outpatient Department of Gynaecology and Obstetrics, AIIMS, New Delhi. On the basis of Hb values, they were grouped into non-anaemic (11.0  Hb  13.0; n  272) and anaemic group (8.0  Hb  11.0 g/dl; n  248). Both oral and written consent was obtained from each participant. The women who did not take any iron supplementation in

Correspondence: D. N. Rao, Room. No. 3030, Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi-110029, India. E-mail: [email protected]

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2  H. Shankar et al. the previous 3 months were enrolled into the study. The inclusion criteria included primigravid status of: age 19–30 years; having an Hb range 8.0–13.0 g/dl; and a body mass index (BMI) range of 18–22 kg/m2. Exclusion criteria included: age  19 and  30; a history of chronic illness or any metabolic disease, such as diabetes mellitus, malignancy and heart disease; infectious diseases, such as tuberculosis, HIV, endocrine disorders. After enrolment, 5 ml venous blood was drawn and anticoagulated with K EDTA at a concentration of 1.5 mg/ml. The blood samples were analysed for Hb, haematocrit (Hct), red blood cells (RBC), total leucocyte count (TLC) and biochemical parameters viz. fasting blood sugar, sodium, potassium, calcium, albumin, globulin, creatinine, total protein, total bilirubin, total cholesterol and alkaline phosphatase, by means of an automated cell counter Sysmax A-380. However, mean corpuscular haemoglobin (MCH), mean corpuscular haemo­globin concentration (MCHC) and mean corpuscular volume (MCV) values were calculated with the help of standard formulae, described elsewhere (Sarma 1990). All measurements were made within 2 h of venipuncture. Data was analysed using SPSS for windows (version 20.0) and the results were expressed as means  SE. Mean values were compared using the student’s unpaired t-test. Differences were considered to be statistically significant at an error probability of   0.05 (p  0.05). Ethical approval for this study was obtained from the Institutional Ethical Committee of All India Institute of Medical Sciences, New Delhi, India. The values of haematological and biochemical parameters for reference purposes were considered from the study described elsewhere (Queenan et al. 2010). These already reported reference values were used for comparing the results, to check whether the obtained values comply with the published standards.

Table II. Haematological profile of non-anaemic and anaemic primigravid women (mean  SE).

Parameters Haemoglobin (g/dl) Total leukocyte count ( 103/ml) Haematocrit (%) Red blood cell count ( 106/ml) MCH (pg/cell) MCHC (g/dl) MCV (fl oz)

Non-anaemic primigravid (n  272)

Anaemic primigravid (n  248)

p value

11.96  0.05 8.63  247.7

10.08  0.05 8.13  124.1

 0.0001 NS

36.08  0.17 4.27  0.10

32.95  0.38 3.78  0.03

 0.0001  0.0001

28.58  0.24 33.25  0.14 86.05  0.62

27.23  0.30 31.08  0.25 88.76  1.19

0.0004  0.0001 0.038

MCH, mean corpuscular haemoglobin; MCHC, mean corpuscular haemoglobin concentration; MCV, mean corpuscular volume; NS, not significant.

AP as compared with NAP women. TLC was comparable in both the groups, whereas MCV was significantly higher (p  0.038) in AP women (Table II). Although all the biochemical values obtained were within the published normal reference range (Queenan et al. 2010), most of the parameters were still influenced by anaemia during pregnancy and were significantly different between both the groups: serum potassium level was found significantly decreased (p  0.009), along with albumin, total protein and calcium levels in AP, compared with NAP women (p  0.001). Furthermore, alkaline phosphatase level was significantly higher (p  0.002) in AP women. Apart from these, the rest of the studied parameters showed no significant differences between the groups (Table III). Table IV comprises the relevant reported values of haematological parameters published in various studies.

Results The presented observations are a part of the Anemia Task Force Group activity, Indian Council of Medical Research, India, and are represented in Tables I–III. Table I represents the anthropometric and haemodynamic characteristics of respondents, which showed significantly decreased body weight (p  0.029) and increased body temperature (p  0.041) in AP compared with NAP women. Mean age and BMI were found to be similar in both the groups. All other studied parameters were comparable in both the groups, except diastolic blood pressure, which was low in AP women but statistically non-significant (p  0.057). All the haematological values were within normal reference range among the two groups, as expected; but there were significantly decreased values (p  0.001) of Hb concentration, Hct percentage, RBC count, MCH and MCHC concentration, observed in Table I. Anthropometric and haemodynamic characteristics of non-anaemic and anaemic primigravid women (mean  SE).

Parameters Age (years) Height (cm) Weight (kg) Body mass index (kg/m2) BP systolic (mmHg) BP diastolic (mmHg) Heart rate (per min) Temperature (°F)

Non-anaemic primigravid (n  272)

Anaemic primigravid (n  248)

p value

23.08  0.19 156.2  0.50 53.71  0.92 21.59  0.22 110.6  0.55 72.06  0.48 85.82  0.53 98.21  0.04

23.14  0.18 156.3  0.44 51.31  0.57 21.17  0.21 110.3  0.61 70.67  0.55 85.59  0.68 98.31  0.03

NS NS 0.029 NS NS 0.057 NS 0.041

­BP, blood pressure; NS, not significant.

Discussion The study compared the anthropometric, haemodynamics, haematological and biochemical indices in AP and NAP women, with matching socioeconomic status, income and education. The participants without any previous or present history of any medical complexities of metabolism, having an Hb range of 8.0–13.0 g/dl and a BMI of 18–22 kg/m2 were selected for the study. Hence, the findings may be applied as normative values for north Indian primigravid women. The study recorded non-significantly reduced diastolic blood pressure, which might be due to the reduced RBCs observed in AP Table III. Biochemical profile of non-anaemic and anaemic primigravid women (mean  SE).

Parameters

Non-anaemic primigravid (n  272)

Anaemic primigravid (n  248)

p value

Fasting blood glucose (mg/dl) Sodium (mEq/l) Potassium (mEq/l) Albumin (g/dl) Globulin (g/dl) Total protein (g/dl) Creatinine (mg/dl) Alkaline phosphatase (U/l) Total Bilirubin (mg/dl) Cholesterol (mg/dl) Calcium (mg/dl)

85.29  0.52 137.9  1.38 4.28  0.03 4.49  0.03 2.99  0.03 7.43  0.05 0.78  0.06 78.64  4.25 0.54  0.01 161.8  1.75 9.40  0.04

84.19  0.56 136.9  1.04 4.16  0.03 4.25  0.03 2.94  0.03 7.17  0.05 0.67  0.02 100.8  6.04 0.64  0.08 159.9  2.16 9.14  0.04

NS NS 0.009  0.0001 NS 0.0004 NS 0.002 NS NS  0.0001

­NS, not significant.

Comparison of haematological and biochemical changes  3 Table IV. Reported haematological values at the 2nd trimester of pregnancy. Reference range/values (mean  SE) Study

Hb (g/dl)

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12.2 (10.4–14) Shen et al. (2010)* Schultink et al. (1993) 11.1  1.0 Queenan et al. (2010) 9.7–14.8 James et al. (2008) 11.41  1.16 Ogbodo et al. (2012)† 9.59  0.13 Sharma and Nagar (2013)‡ 7.78  0.39 Kumar et al. (2013)‡ 9.81 Al-Kuran et al. (2012) 10.8  1.57 Akinbami et al. (2013) 10.81  1.72 Onwukeme and Uguru (1990) 11.75  2.52 Osonuga et al. (2011) –

Hct (%) 36.0 (31–41) 31.2  2.9 30.0–39.0 33.12  3.0 27.92  0.37 28.38  2.43 – 32.5  4.63 29.76  5.21 36  7.06 32.45  4.38

RBC count ( 106/ml)

MCV (fl oz)

MCH (pg/cell)

MCHC (g/dl)

4.05 (3.35–4.75) 90.3 (82.3–98.2) 30.6 (27.8–33.4) 33.8 (32.2–35.4) – – – – 2.81–4.49 82.0–97.0 30.0–33.0 – 3.80  0.33 87.49  7.02 30.15  3.01 34.42  1.30 – – – – 3.56  0.47 77.52  4.32 21.32  2.50 26.32  2.94 – – – – 3.91  0.63 84.1  9.68 28.1  3.52 33.3  1.22 – 78.38  5.72 28.63  2.50 36.49  1.08 – – – – – – – –

TLC ( 103/ml) 8.3 (4.3–12.2) – 5.6–14.8 9.66  2.84 – – – 8.3  2.67 7.88  2.32 6.41  2.88 7.52  2.74

­ b, haemoglobin; Hct, haematocrit; MCH, mean corpuscular haemoglobin; MCHC, mean corpuscular haemoglobin concentration; MCV, mean corpuscular volume; RBC count, H red blood cell count; TLC, total leukocyte count. *Values reported at 10–14 weeks’ gestation. †Values expressed as mean  SE. ‡Values reported for anaemia during pregnancy.

women. Hypotension in pregnancy is more frequently observed in cases of anaemia and also leads to increased risk of abortions and premature deliveries (Harsányi and Kiss 1985). However, Zhang and Klebanoff (2001) reported contradictory findings, stating the effects of various confounding risk factors (young age, short, light and lean stature, poverty and gaining less weight) on low blood pressure. After controlling for these factors, no association was observed with preterm birth in their study. In the current study, all participants were from a middle socioeconomic group, with similar age, height and BMI; however, a significant difference in body weight (95% confidence interval, CI: 0.24–4.66) was observed between the two groups when allocated on the basis of Hb values. Thus, it may be inferred that low body weight might be another contributing factor for the low diastolic blood pressure observed in AP women. The difference in body temperature was also found significant between the two groups (CI: –0.209 to –0.004). Anaemia might be the possible cause for this significantly increased body temperature in AP, mainly attributed with iron deficiency, which plays a central role in thermoregulation in two ways: affecting heat production by compromising thyroid hormone response and rate of heat loss by modulating competing demands of body for tissue oxygenation with respect to decreased blood flow in order to minimise body heat loss (Brigham and Beard 1996). Thus, the reduced delivery of oxygen to the tissues leads to heat production in case of anaemia and similar results were obtained in the present study in which significantly raised body temperature was found in AP when compared with NAP (Table I). A significant difference was observed in Hb and Hct percentage (p  0.001; CI: 1.73–2.02 and CI: 2.34–3.92) of AP compared with NAP women (∼ 33% vs ∼ 36%). The decreased Hct percentage might be due to plasma volume expansion in anaemia during pregnancy leading to haemodilution, fluid retention via hormonal regulations and iron deficiency (James et al. 2008; Khoigani et al. 2012). Recently, low levels of Hb and Hct during the first and second half of the pregnancy have been reported to be associated with complications, such as pre-eclampsia and premature preterm rupture of membranes (Khoigani et al. 2012). Apart from all other haematological parameters, MCV was found to be significantly higher (CI: –5.28 to –0.15), which showed a larger size of RBCs in AP women. Furthermore, lower values of MCH and MCHC (CI: 0.61–2.09 and CI: 1.63–2.72) were observed, due to a lesser amount of Hb present in the RBCs and given volume of packed cells, respectively; revealed normocytic

hypochromic anaemia in AP women. The values obtained were within the reported normal reference ranges. The potassium level also significantly declined in AP women (CI: 0.03–0.21) though values lie within the range considered for reference purposes (Queenan et al. 2010), However, slight variation was observed from the values reported in a study where the serum potassium level was recorded during different trimesters of pregnancy (Tomala et  al. 1994). The reduced albumin and total protein levels observed in AP women (CI: 0.15–0.34 and CI: 0.11–0.39) might be due to the protein energy malnutrition. This may be supported with the high MCV and low Hct observed in AP women (Table II). Thus, increased dietary nutrient intake should be taken into consideration that will not only improve the growth and development of the baby but will also help the woman to adapt to changes for healthy childbirth (Ogbodo et al. 2012). The difference in the serum level of calcium was also observed among the groups (CI: 0.16–0.37). Calcium is the most abundant mineral in the body and in the blood; it exhibits three forms, which are in equilibrium with one another. One of the forms is bound to albumin that represents 30–45% of total calcium in blood (Tran 2005). Abnormal total blood calcium concentration may arise from alteration of plasma albumin concentration. The significantly lower calcium value obtained in the current study is well in contrast with reduced levels of albumin in AP women (Table III), which is in accordance with the observation of Hanna (2009). In India, many studies have been conducted, which have studied haematological variables during pregnancy (Shah 2012; Sharma and Nagar 2013; Kothari et al. 2013; Kumar et al. 2013) but none of the studies provided the normative values for AP and NAP women. For a similar gestation period during pregnancy, the studies reported varying results (Table IV). Although a few studies have attempted to derive normal reference values of haematological indices during pregnancy for a specific population (Shen et al. 2010; James et al. 2008; Al-Kuran et al. 2012; Akinbami et al. 2013; Onwukeme and Uguru 1990), none of them compared the values between anaemic and non-anaemic pregnancy. Furthermore, a literature survey suggests that a comparison of haematological, haemodynamics and biochemical parameters between AP and NAP women has not been reported. Very recently, Al-Kuran et al. (2012) validated the reportable indices of haematology, liver and renal function in pregnancy in Middle Eastern population and the data was found consistent with the reported data for other populations. A prospective longitudinal study was performed to

4  H. Shankar et al. investigate the haematological profile during pregnancy on Chinese women and the investigators compared it with established values of white and black women. They found the lower reference values for Hb and platelet count during pregnancy in Chinese women as compared with those of White and Black women (Shen et al. 2010). In another study, James et al. (2008) compared the values obtained in haematological profiles of pregnant primigravid Jamaican women with the established norms and found it them to be in contrast with the published standards.

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Conclusion Ideally, the reference values for these parameters should be defined for specific populations, as the findings would be the true reflection of the blood profile from local inhabitants, which would be less diversified due to the non-involvement of various confounding factors, such as ethnicity, race, lifestyle, environmental set-up, genetic make-up, etc. Most of the studies have compared haematological parameters during pregnancy with non-pregnant women (Shah 2012; Kothari et al. 2013; Onwukeme and Uguru 1990; Osonuga et al. 2011) and a few have considered the already published values as reference standard for interpretation of their results (Shah 2012; Sharma and Nagar 2013). Since the results of biochemical tests during pregnancy may also differ from normal reference ranges, they may be mistakenly interpreted as abnormal and result in unnecessary and potentially dangerous therapeutic actions (Tran 2005). It is imperative to establish normative values for north Indian or similar populations and compare the haematological and biochemical markers in anaemic and non-anaemic pregnancy, since these indices vary widely under the influence of various confounding factors and thus should be critically evaluated.­­ Declaration of interest:  The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper. The authors are highly grateful to Indian Council of Medical Research for providing funding for conducting the present study.

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