Alteration of circulating micronutrients with overt and occult infections in anaemic Guatemalan preschool children

Associations between serum C-reactive protein and serum zinc, ferritin, and copper in Guatemalan school children

Inflammation affects trace nutrient concentrations, but research on copper and particularly in children is limited. We assessed associations between serum C-reactive protein (CRP) and zinc, iron, copper, and other biomarkers (alkaline phosphatase, hemoglobin, and albumin), in 634 healthy 6- to 11-year-old Guatemalan schoolchildren. CRP was measured by a standardized, high-sensitive method. For significant associations with CRP, we stratified nutrient concentrations across categories of CRP and compared concentrations above and below several CRP cutoff points (0.5, 1, 3, 5, and 10 mg/L), and then adjusted values using correction factors (ratios of geometric means of the nutrients in the low and high groups). Prevalence of serum zinc (<65 μg/dL0, ferritin (<15 μg/L), and copper (<90 μg/dL) deficiency were 21%, 2.1%, and 23.8%, respectively. Median (25th and 75th percentiles) CRP was 0.56 (0.26 and 1.54) mg/L. CRP concentration was positively associated with ferritin and copper concentrations (r = 0.23 and 0.29, respectively; P < 0.0001) but not with zinc and other biomarkers (P > 0.05). Regardless of CRP cutoffs, high (> cutoff) vs. low (≤ cutoff) CRP levels had higher ferritin and copper concentrations and lower prevalence of copper deficiency of <90 μg/dL (P < 0.05). Adjustment for inflammation had the greatest influence on recalculated prevalence for the CRP 0.5 mg/L cutoff. The low ferritin prevalence hardly changed (from 2.1% to 2.5%) while the low copper prevalence changed appreciably (from 23.8% to 31.2%). In conclusion, CRP was positively associated with ferritin and copper but not with zinc concentrations. Adjustment for inflammation had little effect on low ferritin prevalence, low to begin with, and a large impact on low copper prevalence. High-sensitive CRP methods and the use of very low CRP cutoffs may be more accurate than traditional CRP methods in the adjustment of serum copper concentrations for inflammation in healthy school children.

Trace element status and inflammation parameters after 6 months of Roux-en-Y gastric bypass

BACKGROUND

Knowledge about the practical consequences of the nutritional status of Fe, Zn, and Cu and inflammation in obesity is limited. The objective of this study was to evaluate changes on trace element status and their potential associations with selected inflammation parameters in patients after Roux-en-Y gastric bypass (RYGBP).

METHODS

Sixty-three women (mean age, 36.9 ± 9.2 years, body mass index, 43.8 ± 4.3 kg/m²) were evaluated at baseline and 6 months after RYGBP. Anthropometric (weight, waist circumference), body composition (fat mass and fat-free mass), dietary (nutrient intakes), and metabolic and inflammation (glucose, insulin, HOMA-IR, adiponectin, HDL-cholesterol, LDL-cholesterol, triglycerides, hs-CRP, leukocytes, polymorphonuclear neutrophils (PMN)) parameters were determined in addition to selected indices of Fe, Zn, and Cu status.

RESULTS

All but one (HDL-cholesterol) metabolic and inflammation parameters had significant differences when compared before and after RYGBP. Hemoglobin, serum ferritin, the size of the rapidly exchangeable zinc pool, and plasma copper decreased after RYGBP. Plasma and hair zinc, as well as zinc protoporphyrin increased. The change in Hb was significantly associated (p < 0.05) to the change in leukocytes (r = 0.33) and adiponectin (r = -0.44). Zinc protoporphyrin change was associated to the change in PMN (r = 0.32) and HDL-cholesterol (r = -0.29). No other associations between the changes of the rest of Fe, Zn, and Cu parameters with the changes of any of the metabolic and inflammation parameters were observed.

CONCLUSION

RYGBP produced significant weight and fat mass losses, with improvement of metabolic and inflammation parameters. Iron, zinc, and copper status were impaired after the surgery.

Vitamin A for non-measles pneumonia in children

BACKGROUND

Acute respiratory infections, mostly in the form of pneumonia, are the leading causes of death in children under five years of age in developing countries. Some clinical trials have demonstrated that vitamin A supplementation reduces the severity of respiratory infection and mortality in children with measles.

OBJECTIVES

To determine whether adjunctive vitamin A is effective in infants and children diagnosed with non-measles pneumonia.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2004); MEDLINE (1996 to November Week 3, 2004); EMBASE (1990 to September 2004); LILACS (9 January 2004); CINAHL (1990 to November 2004); Biological Abstracts (1990 to November 2004) and Current Contents (1990 to September 2004); and the Chinese Biomedicine Database (CBM) (1994 to November 2004).

SELECTION CRITERIA

Only parallel-arm, randomised and quasi-randomised controlled trials in which children (younger than 15 years old) with non-measles pneumonia were treated with adjunctive vitamin A were included.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed trial quality. Study authors were contacted for additional information.

MAIN RESULTS

Five trials involving 1453 infants and children were included. There was no significant reduction in the mortality associated with pneumonia in children treated with vitamin A compared to those who were not (pooled odds ratio (OR) 1.49; 95% confidence interval (CI) 0.66 to 3.35). In addition, there was a lack of a statistically significant effect on duration of stay in hospital (weighted mean difference (WMD) 0.08; 95% CI -0.43 to 0.59). Vitamin A was associated with a 39% reduction in antibiotic firstline failure (OR 0.65; 95% CI 0.42 to 1.01). Children receiving vitamin A were no more likely to experience vomiting (OR 0.77; 95% CI 0.45 to 1.33), diarrhoea (OR 0.57; 95% CI 0.31 to 1.05), bulging of the fontanelles (OR 8.25; 95% CI 0.44 to 155.37) or irritability (OR 0.93, 95% CI 0.56 to 1.57) than those not receiving vitamin A. There was no statistical significance between vitamin A and placebo groups (OR 0.90; 95% CI -1.10 to 2.90) in chest x-ray results. Disease severity after supplementary high-dose vitamin A was significantly worse in children who received vitamin A compared with placebo. Low-dose vitamin A was associated with a significant reduction in the recurrent rate of bronchopneumonia (OR 0.12; 95% CI 0.03 to 0.46).

AUTHORS' CONCLUSIONS

The evidence did not suggest a significant reduction with vitamin A adjunctive treatment in mortality, measures of morbidity, nor an effect on the clinical course of pneumonia in children with non-measles pneumonia. However, not all studies measured all outcomes, limiting the number of studies that could be incorporated into the meta-analyses, so that there may have been a lack of statistical power to detect statistically significant differences.

Plasma zinc concentrations are depressed during the acute phase response in children with falciparum malaria

Plasma concentrations of some micronutrients are altered in the setting of acute infectious or inflammatory stress. Previous studies have provided conflicting evidence concerning the extent and direction of changes in plasma zinc concentrations during the acute phase response. We carried out an observational cohort study in 689 children enrolled in a randomized trial of zinc supplementation during acute falciparum malaria in order to evaluate the relation between plasma zinc concentration and the acute phase response. Plasma zinc was measured by atomic absorption spectrophotometry. On admission, 70% of all subjects had low plasma zinc (<9.2 micromol/L). Multivariate analysis of predictors of admission plasma zinc showed that admission C-reactive protein (CRP), parasite density, and study site were the most important predictors. Predictors of changes in plasma zinc from admission to 72 h included baseline CRP, change in CRP, treatment group, study site, and baseline zinc concentration. In children with acute malaria infection, baseline plasma zinc concentrations were very low and were inversely correlated with CRP (r = -0.24, P < 0.0001) and the degree of parasitemia (r = -0.19, P < 0.0001). Even when CRP and time were taken into account, zinc supplementation increased plasma zinc concentration from admission to 72 h. When available, plasma zinc concentrations should be interpreted with concurrent measures of the acute phase response such as CRP. In children whose age, diet, and/or nutritional status place them at risk of zinc deficiency, those with low plasma zinc levels should be supplemented with oral zinc and followed for clinical and/or biochemical response.

Predictors of plasma zinc concentrations in children with acute diarrhea

BACKGROUND

Plasma and serum zinc concentrations are the most widely used markers of zinc status in individual persons and populations.

OBJECTIVE

The objective was to identify factors that influence plasma zinc concentrations during acute childhood diarrhea.

DESIGN

This was a cross-sectional study of 1757 cases of acute diarrhea in 6-35-mo-old Nepalese children. The association between plasma zinc concentration and several clinical, anthropometric, socioeconomic, and biochemical variables was estimated in simple and multiple linear regression analyses.

RESULTS

We observed a reduction in the mean plasma zinc concentration of 0.59 (95% CI: 0.44, 0.74) micro mol/L per degree ( degrees C) increase in axillary temperature. Having dysentery and an elevated plasma C-reactive protein concentration was also independently associated with lower plasma zinc. Children with clinical features of dehydration had higher plasma zinc concentrations than did those who were not dehydrated. Furthermore, a decrease in plasma albumin of 1 g/L was associated with a decrease in plasma zinc of 0.25 (95% CI: 0.21, 0.29) micro mol/L. The plasma albumin concentration confounded the associations between some clinical variables and plasma zinc, but the association between axillary temperature and dehydration on one hand and plasma zinc on the other was not substantially influenced by the albumin concentration. Moreover, the plasma zinc concentration increased with an increase in observed hemolysis.

CONCLUSIONS

Dehydration, clinical and biochemical indicators of inflammation and hemolysis, and, when possible, plasma albumin concentrations should be taken into account when the plasma zinc concentration is used to estimate zinc status during episodes of diarrhea in childhood.

Effect of zinc on the treatment of Plasmodium falciparum malaria in children: a randomized controlled trial

BACKGROUND

Zinc supplementation in young children has been associated with reductions in the incidence and severity of diarrheal diseases, acute respiratory infections, and malaria.

OBJECTIVE

The objective was to evaluate the potential role of zinc as an adjunct in the treatment of acute, uncomplicated falciparum malaria; a multicenter, double-blind, randomized placebo-controlled clinical trial was undertaken.

DESIGN

Children (n = 1087) aged 6 mo to 5 y were enrolled at sites in Ecuador, Ghana, Tanzania, Uganda, and Zambia. Children with fever and >or=2000 asexual forms of Plasmodium falciparum/ micro L in a thick blood smear received chloroquine and were randomly assigned to receive zinc (20 mg/d for infants, 40 mg/d for older children) or placebo for 4 d.

RESULTS

There was no effect of zinc on the median time to reduction of fever (zinc group: 24.2 h; placebo group: 24.0 h; P = 0.37), a >or=75% reduction in parasitemia from baseline in the first 72 h in 73.4% of the zinc group and in 77.6% of the placebo group (P = 0.11), and no significant change in hemoglobin concentration during the 3-d period of hospitalization and the 4 wk of follow-up. Mean plasma zinc concentrations were low in all children at baseline (zinc group: 8.54 +/- 3.93 micro mol/L; placebo group: 8.34 +/- 3.25 micro mol/L), but children who received zinc supplementation had higher plasma zinc concentrations at 72 h than did those who received placebo (10.95 +/- 3.63 compared with 10.16 +/- 3.25 micro mol/L, P < 0.001).

CONCLUSION

Zinc does not appear to provide a beneficial effect in the treatment of acute, uncomplicated falciparum malaria in preschool children.

Estimation of the effect of the acute phase response on indicators of micronutrient status in Indonesian infants

Many indicators of micronutrient status change during infection because of the acute phase response. In this study, relationships between the acute phase response, assessed by measuring concentrations of C-reactive protein (CRP), alpha(1)-antichymotrypsin (ACT) and alpha(1)-acid glycoprotein (AGP), and indicators of micronutrient status were analyzed in 418 infants who completed a 6-mo randomized, double-blind, placebo-controlled, supplementation trial with iron, zinc and/or beta-carotene. The acute phase response, defined by raised CRP (plasma concentration >10 mg/L), raised AGP (>1.2 g/L), or both raised CRP and AGP, significantly affected indicators of iron, vitamin A and zinc status, independently of the effects of supplementation. Plasma ferritin concentrations were higher by 15.7 (raised AGP) to 21.2 (raised CRP and AGP) micro g/L in infants with elevated acute phase proteins compared with infants without acute phase response (P < 0.001). In contrast, plasma concentrations of retinol were lower by 0.07 (P < 0.05, raised AGP) to 0.12 (P < 0.01, raised CRP) micro mol/L, and of zinc lower by 1.49 (P < 0.01, raised AGP) to 1.89 (P < 0.05, raised CRP and AGP) micro mol/L. Hemoglobin concentrations and the modified relative dose response were not affected. Consequently, the prevalence of iron deficiency anemia was underestimated in infants with raised acute phase proteins by >15%, whereas the prevalence of vitamin A deficiency was overestimated by >16% compared with infants without acute phase response. Hence, using indicators of micronutrient status without considering the effects of the acute phase response results in a distorted estimate of micronutrient deficiencies, whose extent depends on the prevalence of infection in the population.

New concepts on nutritional management of severe malnutrition: the role of protein

Current guidelines for the management of severe malnutrition are mainly based on new concepts regarding the causes of malnutrition and on advances in our knowledge of the physiological roles of micronutrients. In contrast to the early 'protein dogma', there is a growing body of evidence that severely malnourished children are unable to tolerate large amounts of dietary protein during the initial phase of treatment. Similarly, great caution must be exercised to avoid excessive supply of iron and sodium in the diet, while keeping energy intake at maintenance levels during early treatment. Because severely malnourished children require special micronutrients, a mineral-vitamin mix is added to the milk-based formula diets, which are specially designed for the initial treatment and the rehabilitation phase. To further improve nutritional rehabilitation and reduce cases of relapse, 'ready-to-use therapeutic food' and 'ready-to-eat nutritious supplements' with relatively low protein (10% protein calories) and high fat content (54-59% lipidic calories) have been developed. Although current dietary recommendations do not differentiate between oedematous and nonoedematous forms of malnutrition or between adults and children, there are indications that further clarification is still needed for applying dietary measures for specific target groups.

Determinants of plasma retinol concentrations of middle-aged women in rural China

The purpose of this study was to assess the correlates and possible determinants of plasma vitamin A among middle-aged women in rural China. The vitamin A adequacy of the different diets at the five widely varying survey sites was also assessed. Patterns of correlations among dietary and biochemical measurements were strikingly different from previous studies in Western subjects. Plasma beta-carotene was uncorrelated with beta-carotene intake even after adjusting for potential confounders. In counties with low preformed vitamin A intake, plasma retinol correlated with plasma copper (P = 0.007), which in turn was correlated with dietary intake of copper (P = 0.007). In these counties plasma retinol was correlated with plasma beta-carotene (P = 0.001) and was increased 10% in women in the first 2 y of menopause (P = 0.028). Plasma retinol and C-reactive protein levels are inversely correlated (r = -0.15, P < 0.001), indicating that vitamin A status and inflammatory response may be related but the causal direction is unknown. Despite low intake of vitamin A (county averages of 13-78% of recommended daily allowance [RDA]), and particularly of preformed vitamin A, only 3% of these women had plasma retinol levels below 0.7 mumol/L, considered to indicate possible marginal deficiency. Plasma levels of retinol and beta-carotene were more influenced by intrinsic factors such as menopause, lipid status, retinol requirements, and possibly copper status and inflammation than by extrinsic factors such as diet and lifestyle.