ABSTRACT
Objectives: To determine the prevalence and risk factors of zinc deficiency among young children in rural south-western Burkina Faso. Methods: We collected socio-economic, demographic, feeding practice and morbidity information from a sample of 473 children 6-18 mo of age residing in southern Orodara health district; and measured plasma zinc concentration (PZC) by ICP-AES and C-reactive protein and alpha-1 acid glycoprotein by ELISA to adjust PZC for inflammation. Zinc deficiency was defined as PZC ˂ 65μg/L. Associations between selected risk factors and low PZC were screened in bivariate analyses and assessed by generalized multivariable logistic regression. Results: Mean adjusted PZC was 68.4±13.1 ug/L, and the prevalence of zinc deficiency was 43.5% [95%CI: 38.4-48.7]. The odds of zinc deficiency was significantly higher in households with no livestock ownership as compared to the two highest quintiles of livestock ownership (OR= 2.4- 2.5, p<0.05) and when more households shared the family compound (OR= 1.8, p<0.026 for 3-4 households as compared to 1 household per compound). Religion was also associated with zinc deficiency, but recent child morbidity history and feeding practices were not. Conclusions: There is a high prevalence of zinc deficiency among young children in rural southwestern Burkina Faso, especially among children living in large family compounds. Homestead livestock rearing and possibly some religious/cultural habits may reduce the risk of zinc deficiency.
ABSTRACT
Objectives: To assess how asymptomatic malaria infection affects the interpretation of biomarkers of iron, vitamin A and zinc status after adjustment for elevated acute phase proteins (APP). Methods: Plasma ferritin (pF), transferrin receptor (sTfR), retinol binding protein (RBP) and zinc (pZn) concentrations were measured among 451 asymptomatic children aged 6-23 months in Burkina Faso, and adjusted for elevated APP (C-reactive protein ≥5 mg/L and/or alpha-1-acidglycoprotein ≥1g/L) based on a four-group categorical model, as per Thurnham. Histidine-rich protein II (HRP2) concentrations >0.75 ng/mL were considered indicative of current or recent malaria parasitemia. Results: 57.4% of children had at least one elevated APP, and 48.5% had elevated HRP2. After adjusting for APP, children with elevated HRP2 had higher pF (23.5+1.5 vs. 11.1+0.8 μg/L, P<0.001) and lower RBP (0.79+0.01 vs. 0.92+0.01 μmol/L, P<0.001) vs. those without. Controlling for APP, there were no differences in pZn among those with and without elevated HRP2 (62.9+0.8 vs. 62.9+0.8 μg/dL, P=0.98). sTfR did not differ by APP status when controlling for HRP2, but was increased in children with elevated HRP2 vs. those without (17.6+0.5 vs. 12.3+0.4mg/L, P<0.0001). After adjusting for HRP2, along with APP, the estimated prevalence of iron deficiency (pF<12 μg/L) increased from 38.7% to 50.6% and vitamin A deficiency (RBP<0.84μmol/L) decreased from 33.4% to 27.7%. Conclusions: Current or recent malaria parasitemia affects indicators of micronutrient status, even after adjusting for APP. Adjusting indicators of iron and vitamin A status based only on APP may inaccurately estimate the prevalence of micronutrient deficiencies in settings with a high prevalence of malaria and inflammation.
ABSTRACT
Objectives: Zinc supplements may decrease incidence of diarrhea among young children at risk of zinc deficiency. We estimated the cost-effectiveness of three approaches for delivery of preventive and therapeutic zinc supplements in rural Burkina Faso. Methods: Cost estimates were derived from data collected during a community-based randomized zinc trial, information on ongoing child-health days to distribute public health services, and an indepth study of the current health care system. Diarrhea incidence reduction is based on intent-totreat analysis of zinc trial data. Activity-based costing using an ingredients approach accounts for the costs of mutually exclusive inputs related to defined program activities for each approach. Cost-effectiveness is analyzed and compared across an intermittent preventive zinc (IPZ) approach (quarterly delivery of 10-days of 10 mg/d supplements to childrens’ homes), and a therapeutic approach (10-days of 20 mg/d supplements delivered during an ill-child consultation at a local clinic (TZ-CSPS) or via community-based health worker (TZ-CHW)). We assume 81.6% of children are reached with IPZ and .06% and 52% of diarrhea cases treated with TZ-CSPS and TZCHW, respectively. Results: Estimated annual program cost per additional child reached is $3.52 (IPZ), $3.49 (TZCSPS) and $17.59 (TZ-CHW). Cost per death averted in the first program-year is estimated to be $3164 (IPZ), $7363 (TZ-CSPS), and $14068 (TZ-CHW), assuming a diarrhea case fatality rate of 0.3% and 2.64 episodes of diarrhea/child/year. Estimated cases of diarrhea averted per year are 11.5% (IPZ), 0.9% (TZ-CSPS), and 8.2%(TZ-CHW). Conclusions: IPZ is the most cost-effective approach for a zinc program among our study population.
ABSTRACT
Objectives: To assess the effect of three zinc supplementation strategies, provided with diarrhea and malaria treatment, on zinc, iron and vitamin A status. Methods: During a community-based, cluster-randomized, zinc supplementation trial, we collected venous blood at baseline and after 48 weeks in a random subsample of 451 rural Burkinabe children 6-18 mo old assigned to 4 groups: 7 mg zinc/d, ORS+placebo for diarrhea (DPZ); 10 mg zinc/d for 10d/16wks followed by daily placebo, ORS+placebo for diarrhea (IPZ); daily placebo, ORS+20mg zinc/d for 10d for diarrhea (TDZ); no intervention (NI). Supplemented children were treated for fever and malaria. Blood hemoglobin concentration (Hb) was measured by HemoCue®. Plasma zinc concentration (pZn), measured by ICP-AES, and plasma ferritin (pF), transferrin receptor (TfR) and retinol-binding protein (RBP) concentrations, measured by ELISA, were adjusted for inflammation. Results: High baseline rates of anemia (88.5% had Hb<11 g/dL), iron deficiency (50.5% had pF<12 ug/L; 89.9% had TfR>8.3 mg/L ), vitamin A deficiency (48.9% had RBP<0.83 umol/L) and zinc deficiency (43.5% had pZn<65 ug/dL) were not different by group. Over 48 weeks, pZn increased significantly more in DPZ (+5.8±1.9%) than in TDZ (-0.7±1.8%) and NI (-1.7±1.3%) but not than in IPZ (+2.3±1.7%). 48-week changes in Hb, pF, TfR and RBP did not differ by group. Conclusions: Daily preventive, but not intermittent preventive or therapeutic zinc supplementation, increased pZn over 48 weeks. Zinc supplementation with malaria and diarrhea treatment did not affect iron and vitamin A status.