Anaemia, Malaria and Sickle Cell Disease

Anaemia prevention for reduction of mortality in mothers and children

The relationship of anaemia as a risk factor for child and maternal mortality is described. Maternal case fatality rates, mainly from hospital studies vary from < 1% to > 50%. These large differences in risk were related primarily to differences in available obstetric care for women living in areas with inadequate antenatal and delivery care facilities. The relative risk of mortality associated with moderate anaemia (haemoglobin [Hb] 40-80 g/L) was 1.35 (95% confidence interval [95% CI] 0.92-2.00) and for severe anaemia (Hb < 47 g/L) was 3.51 (95% CI 2.05-6.00). Nutritional-related anaemia mortality is likely to be greater than malarial anaemia-related mortality. With good antenatal and obstetric care most anaemia-related deaths are preventable, and policies to reduce anaemia prevalence should not be divorced from efforts to provide adequate antenatal and delivery facilities for women in developing countries. In children, although mortality was increased with anaemia (< 50 g/L), the evidence for increased risk with less severe anaemia was inconclusive. A survival analysis of Malawian infants indicated that if Hb decreased by 10 g/L after 6 months of age, the risk of dying before 12 months of age increased 1.72 times. Evidence from a number of studies suggests that mortality due to severe malarial anaemia in children is greater than that due to iron-deficiency anaemia. Primary prevention of nutritional and malarial anaemia in young children could lead to reductions in child mortality.

An analysis of anemia and pregnancy-related maternal mortality

The relationship of anemia as a risk factor for maternal mortality was analyzed by using cross-sectional, longitudinal and case-control studies because randomized trials were not available for analysis. The following six methods of estimation of mortality risk were adopted: 1) the correlation of maternal mortality rates with maternal anemia prevalence derived from national statistics; 2) the proportion of maternal deaths attributable to anemia; 3) the proportion of anemic women who die; 4) population-attributable risk of maternal mortality due to anemia; 5) adolescence as a risk factor for anemia-related mortality; and 6) causes of anemia associated with maternal mortality. The average estimates for all-cause anemia attributable mortality (both direct and indirect) were 6.37, 7.26 and 3.0% for Africa, Asia and Latin America, respectively. Case fatality rates, mainly for hospital studies, varied from <1% to >50%. The relative risk of mortality associated with moderate anemia (hemoglobin 40-80 g/L) was 1.35 [95% confidence interval (CI): 0.92-2.00] and for severe anemia (<47 g/L) was 3.51 (95% CI: 2.05-6.00). Population-attributable risk estimates can be defended on the basis of the strong association between severe anemia and maternal mortality but not for mild or moderate anemia. In holoendemic malarious areas with a 5% severe anemia prevalence (hemoglobin <70 g/L), it was estimated that in primigravidae, there would be 9 severe-malaria anemia-related deaths and 41 nonmalarial anemia-related deaths (mostly nutritional) per 100,000 live births. The iron deficiency component of these is unknown.

Etiology of anemia in pregnancy in south Malawi

BACKGROUND

Anemia in pregnancy is a major public health problem in developing countries. In sub-Saharan Africa, such anemia is generally accepted as resulting from nutritional deficiencies, particularly iron deficiency.

OBJECTIVE

We comprehensively assessed the full spectrum of nutritional and nonnutritional factors associated with pregnancy anemia.

DESIGN

Iron, folate, vitamin B-12, and vitamin A were measured in serum in a cross-sectional study of 150 pregnant women in Blantyre, Malawi. Bone marrow aspirates were evaluated, peripheral blood films were examined for malaria parasites, stool and urine samples were examined for helminthic infection, and tests were done for genetic disorders and for HIV infection. C-reactive protein (CRP) concentrations and erythrocyte sedimentation rates were measured as markers of inflammation.

RESULTS

Of the 150 anemic women, 23% were iron deficient with no evidence of folate, vitamin B-12, or vitamin A deficiencies; 32% were deficient in iron and one or more of the other micronutrients; 26% were not iron deficient but had evidence of one of the other micronutrient deficiencies, most often vitamin A; and 19% were not deficient in any of the micronutrients studied. CRP concentrations were notably high in 54% of the anemic women with no nutritional deficiencies and in 73.5% of the anemic women who were iron replete by bone marrow assessment.

CONCLUSION

The role of chronic inflammation as a possible contributing factor to anemia in pregnancy has important implications for the clinical evaluation and treatment of women.

Nutrition and maternal mortality in the developing world

This review relates nutritional status to pregnancy-related death in the developing world, where maternal mortality rates are typically >/=100-fold higher than rates in the industrialized countries. For 3 of the central causes of maternal mortality (ie, induced abortion, puerperal infection, and pregnancy-induced hypertension), knowledge of the contribution of nutrition is too scanty for programmatic application. Hemorrhage (including, for this discussion, anemia) and obstructed labor are different. The risk of death is greatly increased with severe anemia (Hb <70 or 80 g/L); there is little evidence of increased risk associated with mild or moderate anemia. Current programs of universal iron supplementation are unlikely to have much effect on severe anemia. There is an urgent need to reassess how to approach anemia control in pregnant women. Obstructed labor is far more common in short women. Unfortunately, nutritional strategies for increasing adult stature are nearly nonexistent: supplemental feeding appears to have little benefit after 3 y of age and could possibly be harmful at later ages, inducing accelerated growth before puberty, earlier menarche (and possible earlier marriage), and unchanged adult stature. Deprived girls without intervention typically have late menarche, extended periods of growth, and can achieve nearly complete catch-up growth. The need for operative delivery also increases with increased fetal size. Supplementary feeding could therefore increase the risk of obstructed labor. In the absence of accessible obstetric services, primiparous women <1.5 m in height should be excluded from supplementary feeding programs aimed at accelerating fetal growth. The knowledge base to model the risks and benefits of increased fetal size does not exist.

Pregnancy in sickle cell disease in the UK: results of a multicentre survey of the effect of prophylactic blood transfusion on maternal and fetal outcome

OBJECTIVE

To determine the outcome of pregnancies complicated by sickle cell disease in the UK during 1991-1993 and the effect of prophylactic blood transfusion programmes on maternal and fetal outcome.

DESIGN

A multicentre study.

SUBJECTS

Eighty-one pregnancies complicated by sickle cell disease and 100 pregnancies from women of black African descent without haemoglobinopathies to act as a comparative group. Pregnancies complicated by sickle cell disease were divided by the type of haemoglobinopathy and also by transfusion regimen.

MAIN OUTCOME MEASURES

Antenatal and postnatal complications of sickle cell disease, proteinuric hypertension, preterm delivery, emergency delivery by caesarean section, fetal distress, birthweight, perinatal and maternal mortality.

RESULTS

There were two maternal deaths in the 81 pregnancies and the perinatal mortality rate was 60/1000. Antenatal sickling complications occurred in 46.2% of pregnancies and postnatal sickling complications occurred in 7.7% of pregnancies. Pregnancies complicated by sickle cell disease were significantly more likely to be associated with anaemia, preterm delivery, proteinuric hypertension, birthweight below the 10th centile and caesarean section as an emergency procedure than the comparative group. Severe sickling complications occurred more commonly in the third trimester and there was some evidence that a prophylactic transfusion programme reduced the risk of this. Prophylactic transfusion did not improve obstetric outcome when compared with those pregnancies that were untransfused.

CONCLUSIONS

Sickle cell disease remains a severe complicating factor to pregnancy and perinatal mortality and maternal mortality rates in the UK have increased since last reported. A policy of exchange transfusing all women with homozygous sickle cell disease (HbSS) from 28 weeks gestation is recommended to reduce the risk of maternal complications in the third trimester and puerperium. There remains a role for earlier prophylactic blood transfusion programmes in women with poor obstetric and haematological histories.

Pregnancy in sickle cell disease in Bahrain

OBJECTIVE

To review the maternal and fetal complications in pregnant women with sickle cell disease and to compare their pregnancy outcome with those of controls.

DESIGN

A case-control study.

SETTING

Ministry of Health hospitals in Bahrain.

SUBJECTS

147 pregnancies in 140 women with sickle cell disease and 294 controls matched for age and parity.

MAIN OUTCOME MEASURES

The characteristics of women who had crises, the frequency of the crises, hypertensive disorders of pregnancy, infection, diabetes, perinatal mortality and the delivery statistics in the index and control women.

RESULTS

Maternal mortality was 1.4% and perinatal mortality was 73.3/1000 total births in women with sickle cell disease, there were no maternal deaths and the perinatal mortality was 6.8/1000 births in the control group. Anaemia was treated by blood transfusion in 47% of women with sickle cell disease and, of these, 39% had a crisis that appeared to have been precipitated by the transfusion in the absence of any other predisposing factors. The presence of raised HbF did not decrease the number of crises but reduced their severity.

CONCLUSION

Pregnancy in women with sickle cell disease should be monitored very closely as it constitutes a high risk to both the mother and the baby.

Severe anaemia in pregnancy: a problem of primigravidae in rural Zaire

Haemoglobin levels were measured in 2950 pregnant women attending antenatal clinics in Kimpese, Bas Zaire. 72% were suffering from moderate anaemia (haemoglobin (Hb) 7-11 g/dl) and 3.7% from severe anaemia (Hb less than 7 g/dl) at their first visit, before receiving any haematinics or anti-malarial prophylaxis. Haemoglobin levels rose with both increasing parity (P less than 0.001) and age. Multiple regression analysis revealed that parity was significant but age was not. The fall in haemoglobin early in the second trimester was greatest in primigravidae and diminished with successive pregnancies until the fourth. One in 6 primigravidae approached labour with a haemoglobin level less than 7.7 g/dl. Thick blood smears were examined from 379 women who presented in the first and second trimester. 70% of primigravidae had malaria parasitaemia, compared with 13% of multigravidae (P less than 0.001). Early malaria prophylaxis in the first 2 pregnancies is an important primary health care objective if the contribution of malaria to the significant fall in haemoglobin in the second trimester is to be averted.

Tropical obstetrics and gynaecology. 1. Anaemia in pregnancy in tropical Africa

Major causes of anaemia in pregnancy in tropical Africa are malaria, iron deficiency, folate deficiency and haemoglobinopathies: now there is added also the acquired immune deficiency syndrome (AIDS). Anaemia is often multifactorial, with the different causes interacting in a vicious cycle of depressed immunity, infection and malnutrition. Anaemia progresses through 3 stages: compensation, with breathlessness on exertion only; decompensation, with breathlessness at rest and haemoglobin (Hb) below about 70 g/litre; cardiac failure, with Hb below about 40 g/litre. Without treatment, over half of the women with haematocrit less than 0.13 and heart failure die. Maternal anaemia, malaria and deficiencies of iron and folate cause intrauterine growth retardation, premature delivery and, when severe, perinatal mortality. Surviving infants have low birthweights, immune deficiency and poor reserves of iron and folate. They have entered already the vicious cycle of infection, malnutrition and impaired immunity. Treatment with blood transfusions is even more hazardous since the advent of AIDS, and should be limited to saving the life of the mother. Treatment of malaria is complex as chloroquine-resistant strains are now common. Prevention remains relatively easy with proguanil and supplements of iron and folic acid and is highly cost-effective in the improvement of maternal and infant health; it is more important than ever as it avoids the unnecessary exposure of women and infants to HIV transmitted through blood transfusion.

The aetiology of severe anaemia in pregnancy in Ndola, Zambia

The aetiology of severe anaemia (haemoglobin less than 7.0 g dl-1) has been studied in 37 pregnant Zambians. Aetiology was usually multiple; 31 (84%) had Plasmodium falciparum malaria, 23 (62%) were folate deficient, 13 (35%) were iron deficient, one had sickle-cell anaemia and one had the acquired immunodeficiency syndrome (AIDS). Folate deficiency was most often secondary to malarial haemolysis: iron deficiency was nutritional, but hookworm was contributory in about one-third of patients. The anaemia of malaria and folate deficiency was both more common and more severe than anaemia due to iron deficiency; it was seen in younger women although primigravidae were not over-represented, it occurred earlier in pregnancy, and was associated with low birthweight. AIDS must now be included in the differential diagnosis of anaemia in pregnancy. Vigorous antimalarial treatment and prophylaxis are essential in the management and prevention of anaemia in pregnancy. Total dose iron infusion is indicated only when severe iron deficiency anaemia has been proven, and must be accompanied by antimalarial therapy and folic acid supplements. Because of the risk of transmission of human immunodeficiency virus, it is more important than ever to prevent anaemia and malaria in pregnancy, and to give blood transfusion only as a life-saving treatment.

Clinical course of malaria in pregnancy--a prospective controlled study from India

A prospective hospital-based study was conducted from June 1984 to November 1985 in northern India to study the morbidity pattern of malaria in pregnant women. 78 pregnant and 22 non-pregnant women with malarial infection (60% Plasmodium vivax and 40% P. falciparum) were included in the study. The results were analysed according to period of gestation, parity and type of infection. Severity of clinical illness was significantly higher in pregnant patients for both P. vivax and P. falciparum infections. Some striking differences were found in our study when compared with those from African countries. Multigravidas had a slightly higher morbidity than primigravidas, though the difference was not statistically significant. Even though only a small proportion (1.4%) of our pregnant patients were affected by malaria, cerebral malaria, maternal deaths, intrauterine foetal deaths and pre-term labours were much more common.

Maternal mortality--a world wide problem

Death during pregnancy and delivery is one of the leading causes of death among women in the developing countries. A review of literature, and a comparison of the decline of the maternal mortality in Sweden, concludes that maternal mortality is a sensitive socio-economic index of health in the society, but also that this death cause is one of the few that it is really possible to prevent by the impact of medical services - antenatal and delivery care.