The use of adjustment factors to address the impact of inflammation on vitamin A and iron status in humans.

Many nutrient biomarkers are altered by inflammation. We calculated adjustment factors for retinol and ferritin by using meta-analyses of studies containing the respective biomarker and 2 acute phase proteins in serum, C-reactive protein (CRP), and α1-acid glycoprotein (AGP). With the use of CRP and AGP we identified 4 groups in each study: reference (CRP ≤5 mg/L, AGP ≤1 g/L), incubation (CRP >5 mg/L, AGP ≤1 g/L), early convalescence (CRP >5 mg/L, AGP >1 g/L), and late convalescence (CRP ≤5 mg/L, AGP >1 g/L). For each biomarker, ratios of the geometric means of the reference to each inflammation group concentration were used to calculate adjustment factors for retinol (1.13, 1.24, and 1.11) and ferritin (0.77, 0.53, and 0.75) for the incubation, early, and late convalescent groups, respectively. The application of the meta-analysis factors in more recent studies compares well with study-specific factors. The same method was used to calculate adjustment factors for soluble transferrin receptor (sTfR) and body iron stores (BISs) in Lao children. We found no advantage in adjusting sTfR for inflammation; in fact, adjustment decreased iron deficiency. Neither adjusted (10% <0 mg/kg) nor nonadjusted (12% <0 mg/kg) BISs detected as much iron deficiency as did ferritin (18% <12 µg/L) and adjusted ferritin (21% <12 µg/L) unless the cutoff for BISs was increased from 0 to <3 mg/kg. However, we could find no evidence that the larger number of children identified as having BISs <3 mg/kg had risks of anemia comparable to those identified by using ferritin <12 µg/L. In conclusion, both corrected and uncorrected ferritin concentrations <12 µg/L are associated with more iron deficiency and anemia than either sTfR >8.3 mg/L or BISs <0 mg/kg in Lao children.

Impact of inflammation on the biomarkers of iron status in a cross-sectional survey of Lao women and children.

Anaemia is prevalent in South East Asia and Fe deficiency (ID) is considered to be the main cause, but the role of subclinical inflammation in the aetiology is uncertain. In the present study, we determined the influence of inflammation on the biomarkers of Fe status in women and children, and herein, we discuss the proportion of anaemia associated with ID. As part of the 2006 Lao People's Democratic Republic (The Lao PDR) National Nutrition Survey, blood collected from 482 young children and 816 non-pregnant women was analysed. Plasma ferritin, transferrin receptor (sTfR), Hb, C-reactive protein (CRP) and α-1-acid glycoprotein (AGP) concentrations were measured. ID was assessed using ferritin concentrations ( < 12 (children) or < 15 (adults) µg/l), sTfR concentrations (>8.3 mg/l) and body Fe stores (BIS < 0). Elevated CRP (>5 mg/l) and/or AGP (>1 g/l) concentrations were used to categorise inflammation status in order to correct the Fe biomarkers for inflammation. Inflammation was present in 14% of adults and 43% of children. Anaemia was present in 37.6% of both women (Hb concentrations < 120 g/l) and children (Hb concentrations < 110 g/l). Correcting ferritin concentrations for inflammation increased the prevalence of ID from 24.3 to 26% for women and from 18 to 21% for children (P< 0.001 for both). Ferritin concentrations were more helpful in detecting ID than sTfR concentrations or BIS, but regression analysis found that sTfr concentrations explained more of the variance in Hb concentrations in both women (20%) and children (17%) than ferritin concentrations (5 and 1.4%, respectively). Nevertheless, the total variance in Hb concentrations explained was only 26 and 18 % in women and children, respectively, and other factors may be more important than ID in contributing to anaemia in The Lao PDR.

Household food security and buffering mechanisms in Thai and non-Thai households in Nong Loo Sub-district, Sangkhla Buri, Thailand.

This was a cross sectional study to measure any difference between Thai and Non-Thai households in the prevalence of food security and the effect of state and local buffering mechanisms on household food security status in Nong Loo Sub-district in Kanchanaburi Province. Seventy-five point eight percent of 211 households (120 Thai and 91 non-Thai households) were food insecure. Non-Thai households were found to be significantly more food insecure than Thai households (95.6% compared with 60.8%; OR=21.4). Non-Thais tended to have less knowledge of and access to buffering mechanisms; however, this was not statistically significant. Of interest, however, was that no statistically significant association was found between household food insecurity and lack of access to buffering mechanisms. Qualitative interview results suggested that landownership, possession of a Thai card (Government registration card), increased food prices, and a dependence on imported food from other districts were important factors associated with household food insecurity in the sub-district. This survey underlines the importance of the food insecurity as a problem among Thai and, more severely, among non-Thai households and provides stake holders with information that can be used to intensify programs to address this problem. Thailand has a long border area with a high proportion of non-Thai households, and it is likely that similar food insecurity problems exist in other areas also. Further research on nutrition security (as distinct from food security) of this population is recommended in order to better assess the impact of the observed food insecurity.

Thiamine deficiency and parasitic infection in rural Thai children.

A study was carried out to determine whether thiamine deficiency in northeast Thailand is linked with parasitic infection. We assessed the thiamine status and tested for parasitic infections in 231 children between 6 and 12 years of age in Nam Phong District of Khon Kaen Province, Thailand. Thiamine deficiency [thiamine pyrophosphate effect (TPPE) > 20%] and parasitic infections (mostly Strongyloides stercoralis) were identified in 16 and 45% of the children, respectively. No association between thiamine deficiency and parasitic infection was found. The general health of the children, according to Thai standard anthropometric curves, was within the normal range. The suboptimal thiamine status and the high prevalence of parasitic infection require attention.

Estimation of population iodine intake from iodized salt consumed through bouillon seasoning in Senegal.

Universal salt iodization (USI) is the main global strategy to eliminate iodine deficiency. Regulation of USI programs often omits salt used in processed foods, despite their increasing contribution to salt intake. In West Africa, bouillon seasoning is a widely consumed source of salt and is therefore relevant to USI effectiveness. To develop program guidance around iodine in bouillon, iodine retention in 13 bouillon brands commercially available in Senegal was measured over 6 months. Iodine content was measured in broth using various water volumes and cooking times, as well as in rice cooked in the broth. Average iodine loss in bouillon over 6 months in 95% humidity at 40-40.5 °C was 4.5% (13.6% for cubes and 0.8% for powder sachets). Iodine was retained in broth with cooking times of up to an hour and in rice cooked in broth. Modeling of contribution to iodine intake revealed that bouillon is an important source of dietary iodine in Senegal. Results may inform salt iodization standards and regulation in Senegal and countries with similar bouillon consumption levels.