Influence of carotene-rich vegetable meals on the prevalence of anaemia and iron deficiency in Filipino schoolchildren

OBJECTIVE

To determine the effects of eating carotene-rich green and yellow vegetables on the prevalence of anaemia, iron deficiency and iron-deficiency anaemia in schoolchildren.

SUBJECTS AND METHODS

Schoolchildren (n=104), aged 9-12 years, received standardized meals containing 4.2 mg of provitamin A carotenoids/day (mainly beta-carotene) from yellow and green leafy vegetables and at least 7 g dietary fat/day. The meals were provided three times/day, 5 days/week, for 9 weeks at school. Before and after the dietary intervention, total-body vitamin A pool size was assessed by using the deuterated-retinol-dilution method; serum retinol and beta-carotene concentrations were measured by high-performance liquid chromatography; and whole blood haemoglobin (Hb) and zinc protoporphyrin (ZnPP) concentrations were measured by using a photometer and a hematofluorometer, respectively.

RESULTS

After 9 weeks, the mean total-body vitamin A pool size increased twofold (95% confidence interval (CI): -0.11, -0.07 micromol retinol; P<0.001), and serum beta-carotene concentration increased fivefold (95% CI: -0.97, -0.79 micromol/l; P<0.001). Blood Hb (95% CI: -1.02, -0.52 g per 100 ml; P<0.001) and ZnPP increased (95% CI: -11.82, -4.57 microol/mol haem; P<0.001). The prevalence of anaemia (Hb<11.5 g per 100 ml) decreased from 12.5 to 1.9% (P<0.001). There were no significant changes in the prevalence of iron deficiency or iron-deficiency anaemia.

CONCLUSIONS

Ingestion of carotene-rich yellow and green leafy vegetables improves the total-body vitamin A pool size and Hb concentration, and decreases anaemia rates in Filipino schoolchildren, with no effect on iron deficiency or iron-deficiency anaemia rates.

The effect of a school-based weekly iron supplementation delivery system among anemic schoolchildren in the Philippines

OBJECTIVE

To determine the effect of a school-based weekly iron supplementation delivery system (WISDS) on the prevalence of anemia among anemic schoolchildren.

SUBJECTS AND METHODS

Two hundred and forty-two Filipino schoolchildren aged 6-12 years with hemoglobin (Hb) concentration <12 g/dl and enrolled for school year 2003-2004. UNICEF iron-folate tablets containing 60 mg elemental iron and 0.40 mg folic acid were given weekly through directly observed supplementation by the teachers for 27 weeks. Compliance to iron supplementation was monitored by the teachers and was recorded using a monitoring form and a supplementation calendar. Hb concentration, weight and height were determined at baseline and at post-intervention.

RESULTS

At post-intervention, the participants' mean Hb concentration increased by 0.4 g/dl (95% confidence interval =0.3, 0.5 g/dl; P<0.0001), anemia prevalence was reduced by 53.7, and 84.3% of the participants had 100% compliance to supplementation.

CONCLUSIONS

The school-based WISDS reduced anemia prevalence among anemic schoolchildren and resulted in high compliance to and coverage of iron supplementation.

Bacillary disease and health seeking behavior among Filipinos with symptoms of tuberculosis: implications for control

SETTING

Urban and rural communities and urban poor settlements in the Philippines.

OBJECTIVE

To determine bacillary disease and action taking among individuals with symptoms of tuberculosis (TB), and to analyze their implications for TB control.

STUDY DESIGN AND METHOD

Subjects aged 20 years and older were interviewed in the 1997 nationwide stratified multi-cluster survey. Sputum acid-fast smears and cultures were done in subjects with abnormal screening chest radiographs.

RESULTS

Individuals with TB symptoms comprised 18.1% of the population studied. The prevalence of bacillary disease was 39/1000 in symptomatic subjects compared to 13/1000 in asymptomatic subjects. Symptom screening had a 14.3% positive predictive value and a 91.4% negative predictive value for bacillary disease. Significantly more symptomatic than asymptomatic subjects attended chest radiographic screening during the survey. However, in response to their symptoms, the majority (43.0%) took no action or self medicated (31.6%), while 11.8% consulted a private practitioner, 7.5% a public health center, 4.4% a hospital, and 1.7% a traditional healer.

CONCLUSION

Sputum smear examination after symptom screening was acceptable for case finding. The health seeking behavior of subjects with TB symptoms was inappropriate. A health education program and public-private collaboration in directly observed therapy, short course (DOTS) are essential for TB control in the Philippines.

Efficacy of a vitamin A-fortified wheat-flour bun on the vitamin A status of Filipino schoolchildren

BACKGROUND

Wheat flour is a possible food vehicle for vitamin A fortification.

OBJECTIVE

This study assessed the efficacy of consumption of a vitamin A-fortified wheat-flour bun (pandesal) on the vitamin A status of school-age children.

DESIGN

This was a double-masked clinical trial conducted in 396 and 439 children aged 6-13 y attending 4 rural schools in the Philippines. The children were randomly assigned to a vitamin A-fortified (experimental) or nonfortified (control) group. A 60-g vitamin A-fortified pandesal (containing approximately 133 microg retinol equivalents) or a nonfortified pandesal was consumed by the children 5 d/wk for 30 wk. Vitamin A status, hemoglobin concentration, anthropometric status, morbidity, and dietary intake were assessed at baseline and 30 wk later. A modified relative dose response (MRDR) was assessed in a subsample of 20% of the children ( approximately 75/group) with the lowest initial serum retinol concentration at the 30-wk follow-up.

RESULTS

Baseline serum retinol significantly modified the effect of the intervention. The fortified group, whose initial serum retinol concentrations were below the median, had a 0.07 +/- 0.03-micromol/L greater improvement in serum retinol at the 30-wk follow-up than did the control group (P: = 0.02). Improved vitamin A status was also evident in the MRDR subsample. End-of-study differences in the MRDR showed that vitamin A- fortified pandesal intake decreased the percentage of children with inadequate liver vitamin A stores by 50% (15.3% compared with 28.6%; P: = 0.05).

CONCLUSIONS

Daily consumption of vitamin A-fortified pandesal significantly improved the vitamin A status of Filipino school-age children with marginal-to-low initial serum retinol concentrations.

Bioconversion of plant carotenoids to vitamin A in Filipino school-aged children varies inversely with vitamin A status

BACKGROUND

It is important to understand the factors affecting strategies to improve the vitamin A status of populations. We reported previously that a 3-d deuterated-retinol-dilution (DRD) procedure might be used to indicate total body stores of vitamin A.

OBJECTIVE

We studied the ability of 3-d DRD to detect changes in the body pool size of vitamin A and the effect of vitamin A status on the bioconversion of plant carotenoids to vitamin A.

DESIGN

Two separate, unrelated studies were conducted in 7-13-y-old children with poor or marginal serum retinol concentrations (0.32-0.93 micromol/L) by feeding them controlled diets daily for 5 d/wk for 12 wk, after treatment with an anthelmintic drug. In school 1 (n = 27), lunch and 2 snacks that were provided at school contained 2258 retinol equivalents/d (mostly from orange fruit and vegetables) and 5.3 MJ/d from 33 g fat, 37 g protein, and 209 g carbohydrates; in school 2 (n = 25), 2 snacks provided 2.5 MJ/d from 9.4 g fat, 9.6 g protein, and 119 g carbohydrates, but no carotenes.

RESULTS

In school 1, mean serum beta-carotene increased from 0.12 to 0.62 micromol/L (P = 0.0001) and serum retinol increased from 0.68 to 1. 06 micromol/L (P = 0.0001). In school 2, serum beta-carotene increased from 0.06 to 0.11 micromol/L (P = 0.0001) and serum retinol increased from 0.66 to 0.86 micromol/L (P = 0.0001). In school 1, but not school 2, improvement in serum retinol varied inversely with baseline retinol (r = -0.38, P = 0.048). In both schools, 3-d DRD showed reductions in the ratio of serum deuterated to nondeuterated retinol (D:H retinol) postintervention, denoting improvements in vitamin A status; the higher D:H retinol (ie, the poorer the status) at baseline, the greater the reduction in D:H retinol postintervention (school 1: r = -0.99, P = 0.0001; school 2: r = -0.89, P = 0.0001).

CONCLUSIONS

Three-day DRD can detect changes in the body pool size of vitamin A, although a predictive equation to quantitate total body stores of vitamin A with the use of 3-d data needs to be developed. Bioconversion of plant carotenoids to vitamin A varies inversely with vitamin A status; improvement in status after dietary interventions is strongly influenced by total body stores of vitamin A and is influenced little or not at all by serum retinol.

Tuberculosis in the urban poor settlements in the Philippines

SETTING

Urban poor settlements in the Philippines.

OBJECTIVE

To determine the magnitude of the tuberculosis problem in urban poor settlements in comparison with urban areas studied in the Nationwide Tuberculosis Prevalence Survey.

STUDY DESIGN AND METHOD

A multistage cluster survey of BCG scar, tuberculin test, chest radiography and sputum examination for bacillary disease, in urban poor areas.

RESULTS

The prevalences of culture-positive and smear-positive tuberculosis were 17.5 +/- 2.3 (95% CI 13.3-22.4) and 7.9 +/- 2.3 per thousand (95% CI 2.611.5), respectively. Extrapolated to the total population, the rates in the urban poor settlements were 12.4 +/- 1.7 (95% CI 9.6-16.2) and 5.6 +/- 1.6 per thousand population (95% CI 1.3-8.3), respectively. The prevalence of active pulmonary tuberculosis in subjects aged 10 years or more was 66 +/- 5.6/1000 (95% CI 55-77). The BCG vaccination rate was 72%. The overall prevalence of tuberculosis infection was 66%, and 39% in those aged 5-9 years, corresponding to an annual risk of infection (ARI) of 6.5%.

CONCLUSION

The problem of tuberculosis was substantial in the urban poor settlements, and was appreciably worse than that in the general urban population.

The 1997 Nationwide Tuberculosis Prevalence Survey in the Philippines

SETTING

The Philippines is a developing country where tuberculosis (TB) remains a significant public health problem.

OBJECTIVE

To determine the prevalence of TB as a basis for setting the targets of the National Tuberculosis Control Program.

STUDY POPULATION AND METHODS

A multi-stage cluster survey of a random sample of 21960 subjects from 36 clusters nationwide was undertaken from 2 April to 31 July 1997. BCG scar verification and tuberculin testing was performed for subjects aged 2 months and over, and chest radiography screening was done on subjects 10 years and older. Sputum samples were collected from individuals who were initially assessed to have abnormal chest radiographs to determine the prevalence of bacillary tuberculosis. Acid-fast smear by modified Kinyoun's technique and culture on Löwenstein Jensen were done to demonstrate Mycobacterium tuberculosis.

RESULTS

The prevalence of active pulmonary TB was 42/1000 population. The prevalence of culture-positive and smear-positive cases was 8.1 and 3.1/1000, respectively. The prevalence was similar in urban and rural areas.

CONCLUSION

Morbidity from TB remains high. Allowing for methodological differences from the survey in 1981-1983, the prevalence of active pulmonary TB was unchanged. There was only a minimal decrease, of 37% for smear-positive cases and 25% for culture-positive cases, in the 14-year interval.

Evaluation of the effect of vitamin A-fortified margarine on the vitamin A status of preschool Filipino children

OBJECTIVES

This study assessed the effects of consuming a highly hydrogenated, vitamin A (VA)-fortified margarine not requiring refrigeration on VA status of preschool children.

DESIGN

A double-masked randomized community trial.

SETTING

Six rural villages in Cavite, Southern Luzon, the Philippines.

SUBJECTS

296 and 285 children 3-6 y of age in the VA-fortified (experimental) and non-fortified (control) margarine groups, respectively.

INTERVENTION

Each week for 6 months households were given 250 g of VA-fortified margarine [providing 28.8 micrograms retinol equivalents (RE) per g] or non-fortified (0 microgram RE) margarine of identical appearance for each enrolled child. Children's vitamin A status [serum retinol, xerophthalmia, and conjunctival impression cytology (CIC) status] and dietary intake were assessed at baseline and follow-up; margarine intake was monitored throughout the study.

RESULTS

Daily margarine intake per child averaged 27 g in the experimental group (providing 776 micrograms RE) and 24 g (0 microgram RE) in the control group. After 6 months, mean serum retinol increased from 26.4 to 28.8 micrograms/dl in the experimental group but decreased from 26.6 to 25.1 micrograms/dl in controls (P < 0.001 at 6 months); the multiple-adjusted increment over controls was 2.4 micrograms/dl (P < 0.01). More importantly, the prevalence of low serum retinol (< 20 micrograms/dl) decreased from 25.7 to 10.1% in the experimental group but remained unchanged in controls (26.7 to 27.7%) (P < 0.01 at 6 months). At follow-up no experimental children had developed xerophthalmia but 1.4 and 1.8% of controls developed nightblindness and Bitot's spots, respectively. There were no differences in CIC between groups.

CONCLUSION

Consumption of VA-fortified margarine significantly improved VA status of preschool Filipino children.

Disposal of faeces of children under two years old and diarrhoea incidence: a case-control study

This is a report on the relationship of disposal of faeces of children under two years old and diarrhoeal incidence from a clinic-based case-control study. Based on data on 275 cases and 381 controls recruited from 16 clinics in Metropolitan Cebu in the Philippines over a five-month period, the results showed that unsanitary disposal of young children's stools was associated with a 34% increase (OR = 1.34) in clinically diagnosed diarrhoeas and a 63% increase (OR = 1.63) in pathogen-positive diarrhoeas relative to those who were following sanitary practices. Despite several methodological limitations, the findings suggest that the exposure variable under investigation might be an important risk factor for diarrhoeas. Further studies are indicated because of the value of identifying specific hygiene behaviours related to the transmission of enteric pathogens for purposes of formulating interventions.

Vitamin A deficiency in the Philippines: a study of xerophthalmia in Cebu

An investigation of xerophthalmia was undertaken in four ecological zones in Cebu in the Philippines. One thousand seven hundred fifteen children aged 1 to 16 years were examined in 12 barrios. Clinical, biochemical and anthropometric data were collected from the children. Dietary and socioeconomic information was obtained from the households. Multivariate statistical techniques were used to examine factors possibly associated with xerophthalmia. Of children 47% had deficient or low serum vitamin A levels and 4.5% had clinical signs of xerophthalmia. Approximately 2% had both low serum vitamin A levels and clinical eye signs and were then defined as having active xerophthalmia. Vitamin A deficiency was more prevalent in males than females. Xerophthalmia was most common in the 4 to 6 year old age group. Diarrhea, roundworm infestation and measles were not positively correlated with xerophthalmia but whooping cough and tuberculosis were. Low intakes of carotene and vitamin A were associated with xerophthalmia but protein and fat intakes were not. A higher incidence of xerophthalmia occurred in children of working than nonworking mothers. Data on home production and use of vegetables and fruits are presented. The results of this study are being used to introduce three alternate intervention strategies to control xerophthalmia.