David Mwaniki

Micronutrients in childhood and the influence of subclinical inflammation

In the present paper biomarkers of micronutrient status in childhood and some of the factors influencing them, mainly dietary intake, requirements and inflammation will be examined. On a body-weight basis the micronutrient requirements of children are mostly higher than those of an adult, but most biomarkers of status are not age-related. A major factor that is often overlooked in assessing status is the influence of subclinical inflammation on micronutrient biomarkers. In younger children particularly the immune system is still developing and there is a higher frequency of sickness than in adults. The inflammatory response rapidly influences the concentration in the blood of several important micronutrients such as vitamin A, Fe and Zn, even in the first 24 h, whereas dietary deficiencies can be envisaged as having a more gradual effect on biomarkers of nutritional status. The rapid response to infection may be for protective reasons, i.e. conservation of reserves, or by placing demands on those reserves to mount an effective immune response. However, because there is a high prevalence of disease in many developing countries, an apparently-healthy child may well be at the incubation stage or convalescing when blood is taken for nutritional assessment and the concentration of certain micronutrient biomarkers will not give a true indication of status. Most biomarkers influenced by inflammation are known, but often they are used because they are convenient or cheap and the influence of subclinical inflammation is either ignored or overlooked. The objective of the present paper is to discuss: (1) some of the important micronutrient deficiencies in childhood influenced by inflammation; (2) ways of correcting the interference from inflammation.

Efficacy of iron-fortified whole maize flour on iron status of schoolchildren in Kenya: a randomised controlled trial

BACKGROUND Sodium iron edetic acid (NaFeEDTA) might be a more bioavailable source of iron than electrolytic iron, when added to maize flour. We aimed to assess the effect, on childrens iron status, of consumption of whole maize flour fortified with iron as NaFeEDTA or electrolytic iron. METHODS 516 children, aged 3-8 years, from four schools in Marafa, Kenya, were randomly assigned to four groups. All were given the same amount of porridge five times a week. The porridge for one group was made from unfortified whole maize flour; for the other three groups it was fortified with either high-dose NaFeEDTA (56 mg/kg), low-dose NaFeEDTA (28 mg/kg), or electrolytic iron (56 mg/kg). Concentrations of haemoglobin, plasma ferritin, and transferrin receptor were analysed in samples taken at baseline and at the end of the 5-month intervention. The primary outcome was iron-deficiency anaemia. We analysed data on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT00386074. FINDINGS The prevalence of iron-deficiency anaemia in children given unfortified flour was 10%. Compared with placebo, the prevalence of iron-deficiency anaemia in children given flour fortified with high-dose NaFeEDTA, low-dose NaFeEDTA, and electrolytic iron changed by -89% (95% CI -97% to -49%), -48% (-77% to 20%), and 59% (-18% to 209%), respectively. Consumption of high-dose NaFeEDTA improved all measured iron-status indicators. Low-dose NaFeEDTA decreased the prevalence of iron deficiency but did not noticeably change the prevalence of anaemia. Electrolytic iron did not improve any of these iron-status indicators. Children who were iron-deficient at baseline benefited more from high-dose and low-dose NaFeEDTA than those with sufficient iron at baseline. INTERPRETATION Consumption of whole maize flour fortified with NaFeEDTA caused modest, dose-dependent improvements in childrens iron status. Fortification with electrolytic iron did not improve their iron status. Therefore, in high-phytate flours, NaFeEDTA is more suitable than electrolytic iron for supplementation of iron in the diet.

Obesity and regional fat distribution in Kenyan populations: Impact of ethnicity and urbanization

Background: Obesity is increasing rapidly in Africa, and may not be associated with the same changes in body composition among different ethnic groups in Africa. Objective: To assess abdominal visceral and subcutaneous fat thickness, prevalence of obesity, and differences in body composition in rural and urban Kenya. Subjects and methods: In a cross-sectional study carried out among Luo, Kamba and Maasai in rural and urban Kenya, abdominal visceral and subcutaneous fat thicknesses were measured by ultrasonography. Height and weight, waist, mid-upper arm circumferences, and triceps skinfold thickness were measured. Body mass index (BMI), arm fat area (AFA) and arm muscle area (AMA) were calculated. Results: Among 1430 individuals (58.3% females) aged 17–68 years, abdominal visceral and subcutaneous fat, BMI, AFA and waist circumference (WC) increased with age, and were highest in the Maasai and in the urban population. AMA was only higher with increasing age among males. The prevalence of overweight (BMI ≥ 25) (39.8% vs. 15.8%) and obesity (BMI ≥ 30) (15.5% vs. 5.1%) was highest in the urban vs. rural population. Conclusion: Abdominal visceral and subcutaneous fat thickness was higher with urban residency. A high prevalence of overweight and obesity was found. The Maasai had the highest overall fat accumulation.

Prevalence of glucose intolerance and associated risk factors in rural and urban populations of different ethnic groups in Kenya.

OBJECTIVE To assess the prevalence of glucose intolerance in rural and urban Kenyan populations and in different ethnic groups. Further, to identify associations between lifestyle risk factors and glucose intolerance. RESEARCH DESIGN AND METHODS A cross-sectional study included an opportunity sample of Luo, Kamba, Maasai, and an ethnically mixed group from rural and urban Kenya. Diabetes and IGT were diagnosed using a standard OGTT. BMI, WC, AFA, AMA and abdominal subcutaneous and visceral fat thicknesses, physical activity and fitness were measured. Questionnaires were used to determine previous diabetes diagnosis, family history of diabetes, smoking habits, and alcohol consumption. RESULTS Among 1459 participants, mean age 38.6 years (range 17-68 years), the overall age-standardized prevalence of diabetes and IGT was 4.2% and 12.0%. The Luo had the highest prevalence of glucose intolerance among the rural ethnic groups. High BMI, WC, AFA, abdominal visceral and subcutaneous fat thickness, low fitness and physical activity, frequent alcohol consumption, and urban residence were associated with glucose intolerance. CONCLUSIONS The prevalence of diabetes and IGT among different Kenyan population groups was moderate, and highest in the Luo. The role of lifestyle changes and ethnicity on the effect of diabetes in African populations needs further exploration.

Earth-eating and reinfection with intestinal helminths among pregnant and lactating women in western Kenya

We conducted a longitudinal study among 827 pregnant women in Nyanza Province, western Kenya, to determine the effect of earth‐eating on geohelminth reinfection after treatment. The women were recruited at a gestational age of 14–24 weeks (median: 17) and followed up to 6 months postpartum. The median age was 23 (range: 14–47) years, the median parity 2 (range: 0–11). After deworming with mebendazole (500 mg, single dose) of those found infected at 32 weeks gestation, 700 women were uninfected with Ascaris lumbricoides, 670 with Trichuris trichiura and 479 with hookworm. At delivery, 11.2%, 4.6% and 3.8% of these women were reinfected with hookworm, T. trichiura and A. lumbricoides respectively. The reinfection rate for hookworm was 14.8%, for T. trichiura 6.65, and for A. lumbricoides 5.2% at 3 months postpartum, and 16.0, 5.9 and 9.4% at 6 months postpartum. There was a significant difference in hookworm intensity at delivery between geophagous and non‐geophagous women (P = 0.03). Women who ate termite mound earth were more often and more intensely infected with hookworm at delivery than those eating other types of earth (P = 0.07 and P = 0.02 respectively). There were significant differences in the prevalence of A. lumbricoides between geophagous and non‐geophagous women at 3 (P = 0.001) and at 6 months postpartum (P = 0.001). Women who ate termite mound earth had a higher prevalence of A. lumbricoides, compared with those eating other kinds of earth, at delivery (P = 0.02), 3 months postpartum (P = 0.001) and at 6 months postpartum (P = 0.001). The intensity of infections with T. trichiura at 6 months postpartum was significantly different between geophagous and non‐geophagous women (P = 0.005). Our study shows that geophagy is associated with A. lumbricoides reinfection among pregnant and lactating women and that intensities built up more rapidly among geophagous women. Geophagy might be associated with reinfection with hookworm and T. trichiura, although these results were less unequivocal. These findings call for increased emphasis, in antenatal care, on the potential risks of earth‐eating, and for deworming of women after delivery.

Public-private mix for DOTS implementation: what makes it work?

OBJECTIVE To compare processes and outcomes of four public-private mix (PPM) projects on DOTS implementation for tuberculosis (TB) control in New Delhi, India; Ho Chi Minh City, Viet Nam; Nairobi, Kenya; and Pune, India. METHODS Cross-project analysis of secondary data from separate project evaluations was used. Differences among PPM project sites in impact on TB control (change in case detection, treatment outcomes and equity in access) were correlated with differences in chosen intervention strategies and structural conditions. FINDINGS The analysis suggests that an effective intervention package should include the following provider-side components: (1) orienting private providers (PPs) and the staff of the national TB programme (NTP); (2) improving the referral and information system through simple practical tools; (3) the NTP adequately supervising and monitoring PPs; and (4) the NTP providing free anti-TB drugs to patients treated in the private sector. CONCLUSION Getting such an intervention package to work requires that the NTP be strongly committed to supporting, supervising and evaluating PPM projects. Further, using a local nongovernmental organization or a medical association as an intermediary may facilitate collaboration. Investing time and effort to ensure that sufficient dialogue takes place among all stakeholders is important to help build trust and achieve a high level of agreement.

Effects on serum retinol of multi-micronutrient supplementation and multi-helminth chemotherapy: a randomised, controlled trial in Kenyan school children.

Objective: To assess the effects of multi-micronutrient supplementation and multi-helminth chemotherapy on haemoglobin concentration (Hb), using schools as a health delivery system.Study area and population: Nine hundred seventy-seven children between 9 and 18 y of age from 19 primary schools in Bondo District, western Kenya, were included in the trial. The 746 (76.4%) children on whom baseline Hb was available were included in this study.Design: The study was a randomized, placebo-controlled, double-blind, two-by-two factorial trial of the effects of multi-micronutrient supplementation and multi-helminth chemotherapy on Hb after 8 months.Interventions: Single treatment of infected children with albendazole (600 mg) for geohelminths and praziquantel (40 mg/kg) for Schistosoma mansoni and daily supplementation with 13 micronutrients.Results: Multi-micronutrient supplementation (3.5 g/l, 95% CI 1.7, 5.3; P=0.0002) and anthelminthic treatment (2.0 g/l, 95% CI 0.2, 3.9; P=0.03) increased Hb independently (interaction, P=0.33). The effects were also independent of baseline Hb and general nutritional status. The treatment effect was due to reductions in S. mansoni and hookworm intensities of infection, in that Hb increased by 0.4 and 0.2 g/l, respectively, per 100 epg reductions in egg output. Interestingly, among S. mansoni-infected children, the effect of treatment seemed stronger in those with compared to those without co-existing malaria parasitaemia (interaction, P=0.09).Conclusion: Multi-micronutrient supplementation and multi-helminth chemotherapy increased Hb among school children, irrespective of initial Hb and nutritional status.Sponsorship: The Danish International Development Assistance.

Geophagy among school children in western Kenya.

A cross‐sectional study was conducted among 285 school children aged 5–18 years in Nyanza Province, Western Kenya, to determine the prevalence of geophagy and the types and amounts of soil eaten. Stool samples were taken from a subsample of 53 (19%) and their silica content determined to compare the results with the reported geophagy. Geophagy was practised by 73% of the children. The prevalence decreased with age for both sexes up to age 15, then remained stable for girls between 15 and 18 years but continued to decrease for boys in that age range.

Geophagy, iron status and anaemia among primary school children in Western Kenya

As part of a cross‐sectional study among 156 primary school children (median age 13 years, range 10–18) in Western Kenya, geophagy was assessed through interviews. 114 (73.1%) of these children reported eating soil daily. Haemoglobin levels were determined in all 156 children and serum ferritin concentrations in 135. The mean haemoglobin (Hb) concentration was 12.7 g/dl, and median ferritin concentration 27.2 μg/l. Both the proportion of anaemic (Hb < 11.0 g/dl) and of iron‐depleted (ferritin < 12 μg/l) children was significantly higher among the geophageous children than among the nongeophageous (9.6%vs. 0% anaemia; P= 0.037; 18.4%vs. 5.4% iron depletion; P= 0.046). Serum ferritin and haemoglobin concentrations were not correlated (r= 0. 13 5; P= 0. 100). Multiple regression analysis showed that geophagy, hookworm eggs per gram faeces and malaria parasite counts per μl blood were independent predictors of serum ferritin, when controlling for other helminth infections, age and sex, and socio‐economic and educational background of the childrens families and family size (y = 36.038–11.247(geophagy) – 0.010(hookworm epg) + 0.001(malaria parasite counts); R2 = 0.17). Multiple regression analysis with haemoglobin as dependent variable and the same independent variables did not reveal any significant predictors. Analysis of the soil eaten by the children revealed a mean HCl‐extractable iron content of 168.9 mg/kg (SD 44.9). Based on the data on the amounts eaten daily and this mean iron content, soil could provide on average 4.7 mg iron to a geophageous child (interquartile range 2.1–7.1 mg), which is equivalent to 32% of the Recommended Nutrient Intake (RNI) for girls (interquartile range 14–48%) or 42% of the RNI for boys (interquartile range 19–63%). Iron depletion and anaemia are associated with geophagy, but only serum ferritin concentrations were shown to be dependent upon geophagy in the regression model. From the cross‐sectional data no inference about causality can be made. To clarify the possible causal relationships involved, longitudinal studies and iron‐supplementation intervention studies are needed.

Occurrence and characteristics of mandibular fractures in Nairobi, Kenya

Analysis of 355 cases with fractures of the mandible indicated that 74.9% of the cases were due to interpersonal violence and 13.8% were caused by road traffic accidents. The men to women ratio was 8.4:1 and 75.5% of the fracture cases had single fractures while 24.5% had multiple fractures. In cases with a single fracture, the most commonly involved mandibular site was the body (42.2%). The angle of mandible was most frequently fractured (50.5%) in cases with multiple fractures.