The Chakaria food system study: household-level, case-control study to identify risk factor for rickets in Bangladesh

Export-Driven, Extensive Coastal Aquaculture Can Benefit Nutritionally Vulnerable People

Export-orientated shrimp and prawn farming in coastal ghers has been associated with negative environmental, social, and nutritional impacts. This study challenges these perceptions based on field observations from four communities in South West Bangladesh. Most households observed (>60%) were either directly involved in seafood farming or engaged elsewhere in the seafood value chain. Our study set out to establish how the type and location of aquaculture impacted on access to and consumption of aquatic animals. Additionally, we assessed the effects of both household socioeconomic status and intra-household food allocation on individual diet and nutritional outcomes. We used a blended approach, including a 24-h consumption recall on two occasions, analysis of the proximate composition of aquatic animals and biomarkers from whole blood from a sample of the target population. The diverse polyculture systems generated broad social benefits, where “export-oriented” production actually supplied more food locally than to global markets. Key findings: (1) worse-off households achieved higher productivity of farmed aquatic animals on smaller landholding than better-off households with larger landholdings; (2) vegetable production on gher dikes was a significant source of nutrition and income in lower saline gradients; (3) more fish was eaten in lower saline gradients although fish consumption was highly variable within and between households; (4) intra-household allocation of specific foods within diets were similar across communities; (5) recommended nutrient intakes of protein and zinc exceeded daily requirements for adolescent females, but energy, calcium, and iron were below recommended intake levels; (6) n-3 LC-PUFA, expressed as percentage of total fatty acids, in whole blood samples of adolescent females declined with ambient salinity level regardless of household socioeconomic status; (7) analysis of aquatic animals consumed found that mangrove species and tilapia harvested from higher saline ghers contained high levels of desirable PUFAs. These findings suggest that export-driven, extensive coastal aquaculture can be nutrition sensitive when co-products are retained for local consumption.

Aetiology of nutritional rickets in rural Bangladeshi children

OBJECTIVES

A high prevalence of rickets of unknown aetiology has been reported in Chakaria, Bangladesh. Classically, rickets is caused by vitamin D deficiency but increasing evidence from Africa and Asia points towards other nutritional deficiencies or excessive exposure to some metals. The aim of this study was to investigate the aetiology of rickets in rural Bangladeshi children.

METHODS

64 cases with rickets-like deformities were recruited at first presentation together with age-sex-village matched controls. Data and sample acquisition included anthropometry, radiographs, fasted plasma and urinary samples, 24 h weighed dietary intake together with a 24 h urine collection, and ¹³C-breath tests to detect Helicobacter (H.) pylori infection.

RESULTS

One child had active rickets and frank hypovitaminosis D (F, n = 1) and one had deformities with radiological features of Blount disease (M, n = 1). The remaining cases were grouped into those with active rickets, defined as a radiographic Thacher score ≥1.5 (Group A, n = 24, 12M, 12F) and rickets-like bone deformities but not active rickets (Group B, n = 38, 28M, 10F). All children had a low dietary calcium intake, but this was lower in Group A than their controls (mean (SD): 156 (80) versus 323 (249) mg/day, p = 0.005). Plasma 25-hydroxyvitamin D (25OHD) was lower in Group A compared to controls; 63% of Group A and 8% of controls had a concentration <25 nmol/L (p ≤ 0.0001). There was, however, no evidence of differences in skin sunshine exposure. Group A had lower plasma calcium and phosphate and higher 1,25-dihydroxyvitamin D (1,25(OH)₂D) and parathyroid hormone (PTH). 88% of Group A and 0% of controls had undetectable plasma intact fibroblast growth factor (iFGF23), with c-terminal FGF23 (cFGF23) concentrations in the normal range. Urinary phosphate and daily outputs of environmental metals relative to creatinine were higher and tubular maximal phosphate reabsorption per unit glomerular filtration rate (TmP/GFR) was lower in Group A compared to controls. Although less pronounced than Group A, Group B had higher alkaline phosphatase, 1,25(OH)₂D and PTH concentrations than controls but similar calcium intake, TmP/GFR, iFGF23 and cFGF23 concentrations. Mean 25OHD concentrations were also similar to controls and there was no significant difference in the percentage <25 nmol/L (Group B: 13%, controls: 5%, p = 0.2) No group differences were seen in prevalence of anaemia, iron deficiency or H. pylori infection.

CONCLUSION

Nutritional rickets in this region is likely to be predominantly due to low calcium intake in the context of poor vitamin D status and exposure to environmental metals, but not H. pylori infection, anaemia or iron deficiency.

Associations of drinking rainwater with macro-mineral intake and cardiometabolic health: a pooled cohort analysis in Bangladesh, 2016-2019

This study explores the associations of drinking rainwater with mineral intake and cardiometabolic health in the Bangladeshi population. We pooled 10030 person-visit data on drinking water sources, blood pressure (BP) and 24-h urine minerals. Fasting blood glucose (FBG) was measured in 3724 person-visits, and lipids in 1118 person-visits. We measured concentrations of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) in 253 rainwater, 935 groundwater and 130 pond water samples. We used multilevel linear or gamma regression models with participant-, household- and community-level random intercepts to estimate the associations of rainwater consumption with urine minerals and cardiometabolic biomarkers. Rainwater samples had the lowest concentrations of Na, K, Ca and Mg. Rainwater drinkers had lower urine minerals than coastal groundwater drinkers: -13.42 (95% CI: -18.27, -8.57) mmol Na/24 h, -2.00 (95% CI: -3.16, -0.85) mmol K/24 h and -0.57 (95% CI: -1.02, -0.16) mmol Mg/24 h. The ratio of median 24-hour urinary Ca for rainwater versus coastal groundwater drinkers was 0.72 (95% CI: 0.64, 0.80). Rainwater drinkers had 2.15 (95% CI: 1.02, 3.27) mm Hg higher systolic BP, 1.82 (95% CI: 1.19, 2.54) mm Hg higher diastolic BP, 0.59 (95% CI: 0.17, 1.01) mmol/L higher FBG and -2.02 (95% CI: -5.85, 0.81) mg/dl change in high-density lipoprotein cholesterol compared with the coastal groundwater drinkers. Drinking rainwater was associated with worse cardiometabolic health measures, which may be due to the lower intake of salubrious Ca, Mg and K.

Prevalence and risk factors of vitamin D insufficiency and deficiency among 6-24-month-old underweight and normal-weight children living in an urban slum of Bangladesh

OBJECTIVE

We quantified the prevalence of vitamin D status in 6-24-month-old underweight and normal-weight children and identified the socio-economic and dietary predictors for status.

DESIGN

Cross-sectional, baseline data from a nutritional intervention study were analysed. Multinomial logistic regression was used to estimate the odds of being vitamin D deficient or insufficient with the reference being vitamin D sufficient.

SETTING

Urban slum area of Mirpur field site, Dhaka, Bangladesh.

SUBJECTS

Underweight (weight-for-age Z-score <-2·00) and normal-weight (weight-for-age Z-score ≥-1·00) children aged 6-24 months.

RESULTS

Among 468 underweight children, 23·1 % were sufficient, 42·3 % insufficient, 31·2 % deficient and 3·4 % severely vitamin D deficient. Among 445 normal-weight children, 14·8 % were sufficient, 39·6 % insufficient and 40·0 % deficient and 5·6 % severely deficient. With adjusted multinominal regression analysis, risk factors (OR (95 % CI)) for vitamin D deficiency in underweight children were: older age group (18-24 months old; 2·9 (1·5-5·7)); measurement of vitamin D status during winter (3·0 (1·4-6·4)) and spring (6·9 (3·0-16·1)); and maternal education (≥6 years of institutional education; 2·2 (1·0-4·9)). In normal-weight children, older age group (3·6 (1·2-10·6)) and living in the richest quintile (3·7 (1·1-12·5)) were found to be significantly associated with vitamin D insufficiency.

CONCLUSIONS

The study demonstrates a significant burden of vitamin D insufficiency and deficiency in both underweight and normal-weight children <2 years of age from an urban slum of Bangladesh. Identification of risk factors may help in mitigating the important burden in such children.

Calcium Deficiency in Bangladesh: Burden and Proposed Solutions for the First 1000 Days

BACKGROUND

Bangladesh incurs among the highest prevalence of stunting and micronutrient deficiencies in the world, despite efforts against diarrheal disease, respiratory infections, and protein-energy malnutrition which have led to substantial and continuous reductions in child mortality over the past 35 years. Although programs have generally paid more attention to other micronutrients, the local importance of calcium to health has been less recognized.

OBJECTIVE

To synthesize available information on calcium deficiency in Bangladesh in order to inform the design of an effective national calcium program.

METHODS

We searched 3 online databases and a multitude of survey reports to conduct a narrative review of calcium epidemiology in Bangladesh, including population intake, determinants and consequences of deficiency, and tested interventions, with particular reference to young children and women of childbearing age. This was supplemented with secondary analysis of a national household survey in order to map the relative extent of calcium adequacy among different demographics.

RESULTS

Intake of calcium is low in the general population of Bangladesh, with potentially serious and persistent effects on public health. These effects are especially pertinent to young children and reproductive-age women, by virtue of increased physiologic needs, disproportionately poor access to dietary calcium sources, and a confluence of other local determinants of calcium status in these groups.

CONCLUSION

A tablet supplementation program for pregnant women is an appealing approach for the reduction in preeclampsia and preterm birth. Further research is warranted to address the comparative benefit of different promising approaches in children for the prevention of rickets.

Global Consensus Recommendations on Prevention and Management of Nutritional Rickets

BACKGROUND

Vitamin D and calcium deficiencies are common worldwide, causing nutritional rickets and osteomalacia, which have a major impact on health, growth, and development of infants, children, and adolescents; the consequences can be lethal or can last into adulthood. The goals of this evidence-based consensus document are to provide health care professionals with guidance for prevention, diagnosis, and management of nutritional rickets and to provide policy makers with a framework to work toward its eradication.

EVIDENCE

A systematic literature search examining the definition, diagnosis, treatment, and prevention of nutritional rickets in children was conducted. Evidence-based recommendations were developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system that describes the strength of the recommendation and the quality of supporting evidence.

PROCESS

Thirty-three nominated experts in pediatric endocrinology, pediatrics, nutrition, epidemiology, public health, and health economics evaluated the evidence on specific questions within five working groups. The consensus group, representing 11 international scientific organizations, participated in a multiday conference in May 2014 to reach a global evidence-based consensus.

RESULTS

This consensus document defines nutritional rickets and its diagnostic criteria and describes the clinical management of rickets and osteomalacia. Risk factors, particularly in mothers and infants, are ranked, and specific prevention recommendations including food fortification and supplementation are offered for both the clinical and public health contexts.

CONCLUSION

Rickets, osteomalacia, and vitamin D and calcium deficiencies are preventable global public health problems in infants, children, and adolescents. Implementation of international rickets prevention programs, including supplementation and food fortification, is urgently required.

Mineral- and vitamin-enhanced micronutrient powder reduces stunting in full-term low-birth-weight infants receiving nutrition, health, and hygiene education: a 2 × 2 factorial, cluster-randomized trial in Bangladesh

BACKGROUND

The causes of stunting are complex but likely include prenatal effects, inadequate postnatal nutrient intake, and recurrent infections. Low-birth-weight (LBW) infants are at high risk of stunting. More than 25% of live births in low- and middle-income countries are at full term with low birth weight (FT-LBW). Evidence on the efficacy of specific interventions to enhance growth in this vulnerable group remains scant.

OBJECTIVE

We investigated the independent and combined effects of a directed use of a water-based hand sanitizer (HS) and a mineral- and vitamin-enhanced micronutrient powder (MNP) (22 minerals and vitamins) to prevent infections and improve nutrient intake to reduce stunting in FT-LBW infants.

DESIGN

The study was a prospective 2 × 2 factorial, cluster-randomized trial in 467 FT-LBW infants during 2 periods: from 0 to 5 mo postpartum (0-180 d postpartum) and from 6 to 12 mo postpartum (181-360 d postpartum) with the use of 48 clusters. All groups received the same general nutrition, health, and hygiene education (NHHE) at enrollment and throughout the 12 mo. Group assignments initially included the following 2 groups: no HS (control) group or HS from 0 to 5 mo postpartum. These assignments were followed by further divisions into the following 4 groups from 6 to 12 mo postpartum: 1) no HS and no MNP (control), 2) HS only, 3) MNP only, and 4) HS and MNP.

RESULTS

When delivered in combination with NHHE, the use of an HS showed no additional benefit in reducing indicators of infection in the first or second half of infancy or the likelihood of stunting at 12 mo postpartum. FT-LBW infants who received the MNP (with or without the HS) were significantly less likely to be stunted at 12 mo than were controls (OR: 0.35; 95% CI: 0.15, 0.84; P = 0.017).

CONCLUSIONS

The use of a mineral- and vitamin-enhanced MNP significantly reduced stunting in FT-LBW infants in this high-risk setting. The use of a water-based HS did not have an additive effect. This trial was registered at clinicaltrials.gov as NCT01455636.

Global Consensus Recommendations on Prevention and Management of Nutritional Rickets

BACKGROUND

Vitamin D and calcium deficiencies are common worldwide, causing nutritional rickets and osteomalacia, which have a major impact on health, growth, and development of infants, children, and adolescents; the consequences can be lethal or can last into adulthood. The goals of this evidence-based consensus document are to provide health care professionals with guidance for prevention, diagnosis, and management of nutritional rickets and to provide policy makers with a framework to work toward its eradication.

EVIDENCE

A systematic literature search examining the definition, diagnosis, treatment, and prevention of nutritional rickets in children was conducted. Evidence-based recommendations were developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system that describe the strength of the recommendation and the quality of supporting evidence.

PROCESS

Thirty-three nominated experts in pediatric endocrinology, pediatrics, nutrition, epidemiology, public health, and health economics evaluated the evidence on specific questions within five working groups. The consensus group, representing 11 international scientific organizations, participated in a multiday conference in May 2014 to reach a global evidence-based consensus.

RESULTS

This consensus document defines nutritional rickets and its diagnostic criteria and describes the clinical management of rickets and osteomalacia. Risk factors, particularly in mothers and infants, are ranked, and specific prevention recommendations including food fortification and supplementation are offered for both the clinical and public health contexts.

CONCLUSION

Rickets, osteomalacia, and vitamin D and calcium deficiencies are preventable global public health problems in infants, children, and adolescents. Implementation of international rickets prevention programs, including supplementation and food fortification, is urgently required.

Home fortification with calcium reduces Hb response to iron among anaemic Bangladeshi infants consuming a new multi-micronutrient powder formulation

OBJECTIVE

To investigate whether the recommended dietary intake of Ca in anaemic infants compromises the expected Hb response, via home fortification with a new Ca- and Fe-containing Sprinkles™ micronutrient powder (MNP).

DESIGN

A double-blind, randomized controlled, 2-month trial was conducted in Bangladesh. Infants were randomized to one of two MNP intervention groups containing Fe and other micronutrients, with or without Ca. Hb, anthropometrics and dietary intake were measured pre- and post-intervention while family demographics were collected at baseline.

SETTING

Twenty-six rural villages in the Kaliganj sub-district of Gazipur, Bangladesh.

SUBJECTS

One hundred infants aged 6-11 months.

RESULTS

A significant increase in Hb (MNP, 13·3 (sd 12·6) g/l v. Ca-MNP, 7·6 (sd 11·6) g/l; P < 0·0001) was noted in infants from both groups. However, infants receiving MNP without Ca had a significantly higher end-point Hb concentration (P = 0·024) and rate of anaemia recovery (P = 0·008). Infants receiving MNP with Ca were more likely to remain anaemic (OR 3·2; 95 % CI 1·4, 7·5). Groups did not differ in dietary intake or demographic and anthropometric indicators.

CONCLUSIONS

Although both groups showed significant improvement in Hb status, the nutrient-nutrient interaction between Fe and Ca may have diminished the Hb response in infants receiving the Ca-containing MNP.

Vitamin D deficiency amongst minority ethnic groups in the UK: a cross sectional study

BACKGROUND

Vitamin D deficiency is common amongst minority groups in Britain but its magnitude amongst South Asian (SA) and Black African-Caribbean (AC) groups is not well defined. The steroidal, endocrine nature of vitamin D provides it with a putative link with cardiovascular disease (CVD), and we hypothesised that aberrant levels of this hormone would reflect a heightened risk of CVD in these ethnic groups.

METHODS

SA (n=1105, 57% male) and AC (n=748, 51% male) were recruited as part of a community heart failure study from 20 primary care practices, Birmingham, UK. Vitamin D2/D3 levels were measured to determine rates of total vitamin D status, which were age/sex adjusted.

RESULTS

The majority of SAs had severe vitamin D deficiency (42.2%, 95% CI: 39.2-45.1), which was more frequent than in AC (12.5%, 10.2-14.9, p<0.001. Vitamin status in SA and AC was unrelated to the presence of osteoporosis, and on multivariate analysis of SA, vitamin D levels were independently associated with age (β=0.18, p<0.001), haemoglobin (β=0.12, p=0.002), and negatively with alkaline phosphatase (a marker of bone mineralisation, β=-0.11, p=0.022). Amongst AC, vitamin D was independently associated with having ever smoked (β=-0.13, p=0.006) and systolic blood pressure (β=0.10, p=0.038).

CONCLUSIONS

Vitamin D deficiency is a frequent biochemical observation amongst minority groups in Britain but the clinical significance is unclear, and ethnically specific. A proportionate susceptibility to bone disease is not apparent in either minority group.

Demographic, dietary, and biochemical determinants of vitamin D status in inner-city children

BACKGROUND

Reports of clinical rickets are particularly evident in minority infants and children, but only limited analyses of vitamin D are available in this demographic group.

OBJECTIVE

We sought to characterize circulating 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D [1,25(OH)(2)D], and their determinants, including circulating parathyroid hormone (PTH), total alkaline phosphatase activity (ALP), calcium, and phosphorus, in minority infants and children.

DESIGN

We obtained demographic information and blood samples for measurement of PTH, ALP, 25(OH)D, and 1,25(OH)(2)D in >750 6-mo- to 3-y-old children. Dietary intake data were obtained and analyzed.

RESULTS

The mean (±SD) 25(OH)D concentration was 66 ± 22 nmol/L (26.3 ± 8.7 ng/dL). A total of 15% of children had 25(OH)D concentrations less than the recommended target threshold of 50 nmol/L. Combined elevations of PTH and ALP occurred in only 2.5% of children. Determinants of 25(OH)D included vitamin D intake, age (decreasing with age), skin type (greater concentrations in lighter-skinned children than in darker-skinned children), formula use (higher intakes), season (greater concentrations in the summer and fall than in the winter and spring), and, inversely, PTH. The mean 1,25(OH)(2)D concentration was 158 ± 58 pmol/L (60.6 ± 22.5 pg/mL), which was consistent with a reference range of 41-274 pmol/L or 15.7-105.5 pg/mL. Determinants for 1,25(OH)(2)D were age (decreasing with age), sex (greater concentrations in girls than in boys), skin type (greater concentrations in lighter-skinned children than in darker-skinned children), and, inversely, serum calcium and phosphorus.

CONCLUSIONS

Although 15% of subjects were vitamin D insufficient, only 2.5% of subjects had elevations of both PTH and ALP. The greater 25(OH)D concentrations observed with formula use confirm that dietary vitamin D fortification is effective in this demographic group. Circulating 1,25(OH)(2)D is higher in infants than in older children and adults and, in contrast to 25(OH)D, is not directly correlated with nutrient intakes.

Meals and dephytinization affect calcium and zinc absorption in Nigerian children with rickets

Nutritional rickets resulting from calcium insufficiency is common in Nigeria and high dietary phytate is thought to inhibit calcium and zinc absorption. We compared the effects of a high-phytate meal and enzymatic dephytinization on calcium and zinc absorption in Nigerian children with and without rickets. Nineteen children with rickets and 15 age-matched control children, aged 2-10 y, were given calcium (600 mg/d) and ergocalciferol (1250 microg/wk). After 6 wk, calcium and zinc absorption were measured in both groups with and without maize porridge using stable isotopes. One week later, absorption measurements were repeated to assess the effects of enzymatic dephytinization and fermentation of the maize porridge. The phytate concentration of maize porridge (3.87 +/- 0.38 g/kg wet weight) was reduced by enzymatic dephytinization (2.83 +/- 0.41 g/kg; P < 0.001) but not by fermentation (3.35 +/- 0.27 g/kg; P = 0.08). Calcium and zinc absorption were unaffected by the presence of rickets or by fermentation of maize porridge. Calcium absorption was greater with a meal (61.3 +/- 25.1%) than without (27.8 +/- 14.6%; P < 0.001). Zinc absorption was lower with a meal (16.2 +/- 8.0%) than without (63.4 +/- 23.9%; P < 0.001). Enzymatic dephytinization increased relative zinc absorption from a meal by 101 +/- 81% (P < 0.001) but did not affect calcium absorption. Rickets was not associated with impaired calcium or zinc absorption. Calcium absorption was enhanced by maize porridge, but zinc absorption was reduced. Enzymatic dephytinization increased zinc absorption. Multiple strategies may be required to optimize calcium and zinc absorption in deficient populations.

Apparent efficacy of food-based calcium supplementation in preventing rickets in Bangladesh

To determine whether increased Ca intakes can prevent rickets in a susceptible group of children living in a rickets-endemic area of Bangladesh, we conducted a 13-month long, double-blind, clinical trial with 1-to 5-year-old children who did not present with rickets but ranked in the upper decile of plasma alkaline phosphatase (AP) activity of a screening cohort of 1,749 children. A total of 158 children were randomized to a milk-powder-based dietary supplement given daily, 6 days/week, and providing either 50, 250, or 500 mg Ca, or 500 mg Ca plus multivitamins, iron, and zinc. Upon initial screening, 194 healthy children presented with no rachitic leg signs and had serum AP in the upper decile (>260 u/dl) of the cohort. When 183 of those subjects were re-screened after a 7-month pre-trial period, 23 (12.6%) had developed rachitic leg signs, suggesting an annual risk of 21.5% in this cohort. Of those still not presenting with leg signs and completing 13 months of dietary intervention, none showed rachitic leg signs, none showed significant radiological evidence of active rickets, and all showed carpal ossification normal for age after that intervention. These results are consistent with even the lowest amount of supplemental Ca (50 mg/day) being useful in supporting normal bone development in this high-risk population.

Clinical and radiographic improvement of rickets in Bangladeshi children as a result of nutritional advice

BACKGROUND

Calcium-deficiency rickets is common in south-east Bangladesh and responds to calcium supplementation.

AIM

To evaluate the healing effect on active rickets of a five-component nutritional advice programme aimed at doubling dietary calcium intakes.

METHODS

Forty-nine children aged <10 years with mild lower limb deformities and active rickets were followed over a period of 12 months. All were provided with a five-component nutritional advice programme advocating (i) the routine addition of 1 g limestone/kg rice, (ii) consuming small fish (including bones) instead of large ones, and (iii) daily consumption of 5 g ground sesame seeds, (iv) 100 g leafy vegetables and, if possible, (v) 100 ml of milk.

RESULTS

Radiographic scores improved in 90% of children. The response was positively associated with age (r=0.34, n=48, p=0.01) and severity of radiographic score at baseline (r=0.85, n=49, p<0.0001).

CONCLUSIONS

Despite the lack of a statistically significant association between radiographic improvement and compliance with nutritional advice, in mild calcium-deficiency active rickets, nutritional advice may be a cost-effective treatment and possibly a valuable long-term solution to the problem.