Carole Vézina

Effect of prenatal exposure to polychlorinated biphenyls on incidence of acute respiratory infections in preschool Inuit children.

Objective We set out to assess whether environmental prenatal exposure to polychlorinated biphenyls (PCBs) is associated with incidence of acute respiratory infections in preschool Inuit children. Study design We reviewed the medical charts of 343 children from 0 to 5 years of age and evaluated the associations between PCB-153 concentration in umbilical cord plasma and the incidence rates of acute otitis media (AOM) and of upper and lower respiratory tract infections (URTIs and LRTIs, respectively). Results The incidence rates of AOM and LRTIs were positively associated with prenatal exposure to PCBs. Compared with children in the first quartile of exposure (least exposed), children in fourth quartile (most exposed) had rate ratios of 1.25 (p < 0.001) and 1.40 (p < 0.001) for AOM and LRTIs, respectively. There was no association between prenatal PCB exposure and incidence rate of URTIs or hospitalization. Conclusion Prenatal exposure to PCBs could be responsible for a significant portion of respiratory infections in children of this population.

Acute infections and environmental exposure to organochlorines in Inuit infants from Nunavik

The Inuit population of Nunavik (Canada) is exposed to immunotoxic organochlorines (OCs) mainly through the consumption of fish and marine mammal fat. We investigated the effect of perinatal exposure to polychlorinated biphenyls (PCBs) and dichlorodiphenyldichloroethylene (DDE) on the incidence of acute infections in Inuit infants. We reviewed the medical charts of a cohort of 199 Inuit infants during the first 12 months of life and evaluated the incidence rates of upper and lower respiratory tract infections (URTI and LRTIs, respectively), otitis media, and gastrointestinal (GI) infections. Maternal plasma during delivery and infant plasma at 7 months of age were sampled and assayed for PCBs and DDE. Compared to rates for infants in the first quartile of exposure to PCBs (least exposed), adjusted rate ratios for infants in higher quartiles ranged between 1.09 and 1.32 for URTIs, 0.99 and 1.39 for otitis, 1.52 and 1.89 for GI infections, and 1.16 and 1.68 for LRTIs during the first 6 months of follow-up. For all infections combined, the rate ratios ranged from 1.17 to 1.27. The effect size was similar for DDE exposure but was lower for the full 12-month follow-up. Globally, most rate ratios were > 1.0, but few were statistically significant (p < 0.05). No association was found when postnatal exposure was considered. These results show a possible association between prenatal exposure to OCs and acute infections early in life in this Inuit population.

Traditional food consumption is associated with higher nutrient intakes in Inuit children attending childcare centres in Nunavik

OBJECTIVES To describe traditional food (TF) consumption and to evaluate its impact on nutrient intakes of preschool Inuit children from Nunavik. DESIGN A cross-sectional study. METHODS Dietary intakes of children were assessed with a single 24-hour recall (n=217). TF consumption at home and at the childcare centres was compared. Differences in childrens nutrient intakes when consuming or not consuming at least 1 TF item were examined using ANCOVA. RESULTS A total of 245 children attending childcare centres in 10 communities of Nunavik were recruited between 2006 and 2010. The childrens mean age was 25.0±9.6 months (11-54 months). Thirty-six percent of children had consumed at least 1 TF item on the day of the recall. TF contributed to 2.6% of total energy intake. Caribou and Arctic char were the most reported TF species. Land animals and fish/shellfish were the main contributors to energy intake from TF (38 and 33%, respectively). In spite of a low TF intake, children who consumed TF had significantly (p<0.05) higher intakes of protein, omega-3 fatty acids, iron, phosphorus, zinc, copper, selenium, niacin, pantothenic acid, riboflavin, and vitamin B12, and lower intakes of energy and carbohydrate compared with non-consumers. There was no significant difference in any of the socio-economic variables between children who consumed TF and those who did not. CONCLUSION Although TF was not eaten much, it contributed significantly to the nutrient intakes of children. Consumption of TF should be encouraged as it provides many nutritional, economic, and sociocultural benefits.Objectives. To describe traditional food (TF) consumption and to evaluate its impact on nutrient intakes of preschool Inuit children from Nunavik. Design. A cross-sectional study. Methods. Dietary intakes of children were assessed with a single 24-hour recall (n=217). TF consumption at home and at the childcare centres was compared. Differences in childrens nutrient intakes when consuming or not consuming at least 1 TF item were examined using ANCOVA. Results. A total of 245 children attending childcare centres in 10 communities of Nunavik were recruited between 2006 and 2010. The childrens mean age was 25.0±9.6 months (11–54 months). Thirty-six percent of children had consumed at least 1 TF item on the day of the recall. TF contributed to 2.6% of total energy intake. Caribou and Arctic char were the most reported TF species. Land animals and fish/shellfish were the main contributors to energy intake from TF (38 and 33%, respectively). In spite of a low TF intake, children who consumed TF had significantly (p<0.05) higher intakes of protein, omega-3 fatty acids, iron, phosphorus, zinc, copper, selenium, niacin, pantothenic acid, riboflavin, and vitamin B12, and lower intakes of energy and carbohydrate compared with non-consumers. There was no significant difference in any of the socio-economic variables between children who consumed TF and those who did not. Conclusion. Although TF was not eaten much, it contributed significantly to the nutrient intakes of children. Consumption of TF should be encouraged as it provides many nutritional, economic, and sociocultural benefits.OBJECTIVES To describe traditional food (TF) consumption and to evaluate its impact on nutrient intakes of preschool Inuit children from Nunavik. DESIGN A cross-sectional study. METHODS Dietary intakes of children were assessed with a single 24-hour recall (n=217). TF consumption at home and at the childcare centres was compared. Differences in childrens nutrient intakes when consuming or not consuming at least 1 TF item were examined using ANCOVA. RESULTS A total of 245 children attending childcare centres in 10 communities of Nunavik were recruited between 2006 and 2010. The childrens mean age was 25.0±9.6 months (11-54 months). Thirty-six percent of children had consumed at least 1 TF item on the day of the recall. TF contributed to 2.6% of total energy intake. Caribou and Arctic char were the most reported TF species. Land animals and fish/shellfish were the main contributors to energy intake from TF (38 and 33%, respectively). In spite of a low TF intake, children who consumed TF had significantly (p<0.05) higher intakes of protein, omega-3 fatty acids, iron, phosphorus, zinc, copper, selenium, niacin, pantothenic acid, riboflavin, and vitamin B12, and lower intakes of energy and carbohydrate compared with non-consumers. There was no significant difference in any of the socio-economic variables between children who consumed TF and those who did not. CONCLUSION Although TF was not eaten much, it contributed significantly to the nutrient intakes of children. Consumption of TF should be encouraged as it provides many nutritional, economic, and sociocultural benefits.

Exposure to toxic metals and persistent organic pollutants in Inuit children attending childcare centers in Nunavik, Canada.

Arctic populations are exposed to substantial levels of environmental contaminants that can negatively affect childrens health and development. Moreover, emerging contaminants have never been assessed in Inuit children. In this study, we document the biological exposure to toxic metals and legacy and emerging persistent organic pollutants (POPs) of 155 Inuit children (mean age 25.2 months) attending childcare centers in Nunavik. Blood samples were analyzed to determine concentrations of mercury, lead, polychlorinated biphenyls (PCBs), pesticides, brominated flame retardants [e.g., polybrominated diphenyl ethers (PBDEs)] and perfluoroalkyl and polyfluoroalkyl substances [PFASs; e.g. perfluorooctanesulfonate (PFOS) and perfluorooctane (PFOA)]. Lead [geometric mean (GM) 0.08 μmol/L], PCB-153 (GM 22.2 ng/g of lipid), BDE-47 (GM 184 ng/g of lipid), PFOS (GM 3369 ng/L), and PFOA (GM 1617 ng/L) were detected in all samples. Mercury (GM 9.8 nmol/L) was detected in nearly all blood samples (97%). Levels of metals and legacy POPs are consistent with the decreasing trend observed in Nunavik and in the Arctic. PBDE levels were higher than those observed in many children and adolescents around the world but lower than those reported in some U.S. cities. PFOS were present in lower concentrations than in Nunavimmiut adults. There is a clear need for continued biomonitoring of blood contaminant levels in this population, particularly for PBDEs and PFASs.

Consumption of tomato products is associated with lower blood mercury levels in Inuit preschool children.

Some evidence suggests that various diet components and nutrients, including vegetables, fruit and food-derived antioxidants, could mitigate contaminant exposure and/or adverse health effects of contaminants. To examine the effect of the consumption of tomato products on blood mercury levels in Inuit preschool children, 155 Inuit children (25.0±9.1months) were recruited from 2006-2008 in Nunavik childcare centers (northern Québec, Canada). Food frequency questionnaires were completed at home and at the childcare center, and total blood mercury concentration was measured by inductively coupled plasma-mass spectrometry. Multivariate regression analysis was performed after multiple imputation. The median blood concentration of mercury was 9.5nmol/L. Age, duration of breastfeeding, annual consumption frequency of seal meat, and monthly consumption frequency of tomato products were significant predictors of blood mercury levels, whereas annual consumption frequencies of beluga muktuk, walrus, Arctic char, and caribou meat were not. Each time a participant consumed tomato products during the month before the interview was associated with a 4.6% lower blood mercury level (p=0.0005). All other significant predictors in the model were positively associated with blood mercury levels. Further studies should explore interactions between consumption of healthy store-bought foods available in Arctic regions and contaminant exposure.

Impact of a childcare centre nutrition program on nutrient intakes in Nunavik Inuit children.

Purpose: We assessed the impact of a nutrition program implemented in Nunavik childcare centres on Inuit childrens food and dietary intakes. Methods: Two hundred and forty-five Inuit children (age...Purpose: We assessed the impact of a nutrition program implemented in Nunavik childcare centres on Inuit childrens food and dietary intakes. Methods: Two hundred and forty-five Inuit children (aged 25.0 ± 9.6 months) were recruited between 2006 and 2010 in Nunavik childcare centres. Dietary intakes were assessed using a single 24-hour dietary recall (n=217). We compared participants’ energy and nutrient intakes, and the proportions who met iron requirements and Canadas Food Guide – First Nations, Inuit and Metis recommendations, depending on whether or not they attended a childcare centre during the 24-hour dietary reference period. Results: Children who attended a childcare centre on the day of the recall had significantly higher intakes of omega-3 fatty acids, calcium, total iron, bioavailable iron, phosphorus, betacarotene, folate, pantothenic acid, riboflavin, and vitamin K, while a higher proportion of them met the recommended intake for total and bioavailable iron. The proportion of children who m...

Effect of dietary calcium intake on lead exposure in Inuit children attending childcare centres in Nunavik

High blood lead levels (BLLs) can be found in Inuit from Nunavik. At the same time, various nutrients such as calcium could lower lead absorption and toxicity. We examined the effect of dietary calcium intakes on BLLs in 245 preschool Inuit children attending childcare centres in Nunavik. Calcium intake was assessed with one 24-h dietary recall and BLLs were determined by inductively coupled plasma mass spectrometry in whole blood samples. Multiple imputation was performed to deal with missing data. Median blood lead concentration was 0.08 μmol/L. A high proportion of children did not meet the Estimated Average Requirement for vitamin D intake (73 %) and, to a lower extent, for calcium (20 %). Calcium intake was negatively associated with BLLs ( p = 0.0001) while child’s age and energy intake were positively associated with BLLs ( p = 0.015 and p = 0.024, respectively). Consuming traditional foods rich in calcium as well as milk and alternatives may protect against lead exposure.

Usual dietary fatty acid intakes and red-blood-cell membrane fatty acid composition in Inuit children attending child-care centres in Nunavik, northern Québec, Canada.

OBJECTIVES To assess dietary fatty acid intakes and to examine the relationship between dietary sources of n-3 and n-6 PUFA and red-blood-cell (RBC) n-3 and n-6 PUFA composition. DESIGN A cross-sectional study. Dietary intakes were assessed with a 24 h dietary recall. A second recall was performed for 44 % of the children. Usual dietary intakes were estimated with the Software for Intake Distribution Estimation (SIDE). The fatty acid composition was measured in RBC membranes. Multivariate linear regression analyses were performed to explain RBC n-3 and n-6 PUFA concentrations. SETTING Child-care centres in Nunavik, northern Québec, Canada. SUBJECTS One hundred and sixty-seven Inuit children aged 11-53 months. RESULTS A high proportion of the participants had inadequate n-3 and n-6 PUFA intakes (47·9 % and 93·5 %, respectively). Breast-feeding status and consumption of traditional food during the first 24 h dietary recall were significantly associated with RBC n-3 PUFA levels. Older children also tended to have higher RBC n-3 PUFA levels (P = 0·0528), whereas sex, infant formula status and n-3 PUFA dietary intakes were not associated with RBC n-3 PUFA concentrations. RBC n-6 PUFA concentrations were positively associated with breast-feeding status and n-6 PUFA dietary intakes, whereas age, sex and infant formula status were not. CONCLUSIONS The present findings highlight the fact that Inuit pre-school children are not consuming enough n-3 and n-6 PUFA for optimum health. These observations call for actions to increase traditional food intake among Inuit children and to help them and their parents make healthier store-bought food choices.

Using Soluble Transferrin Receptor and Taking Inflammation into Account When Defining Serum Ferritin Cutoffs Improved the Diagnosis of Iron Deficiency in a Group of Canadian Preschool Inuit Children from Nunavik

The prevalence of iron depletion, iron deficient erythropoiesis (IDE), and iron deficiency anemia (IDA) was assessed in preschool Inuit children using soluble transferrin receptor (sTfR) and traditional indicators of iron status while disregarding or taking inflammation into account when defining SF cutoffs. Iron depletion was defined as follows: (1) SF < 15 μg/L regardless of the C-reactive protein (CRP) level and (2) SF < 15 or <50 μg/L with CRP ≤ 5 or >5 mg/L, respectively. IDE corresponded to iron depletion combined with total iron binding capacity > 72 μmol/L and/or transferrin saturation < 16%. Iron depletion and IDE affected almost half of the children when accounting for inflammation, compared to one-third when the SF cutoff was defined regardless of CRP level (P < 0.0001). The prevalence of IDE adjusted for inflammation (45.1%) was very similar to the prevalence observed when sTfR was used as a sole marker of IDE (47.4%). The prevalence of anemia was 15%. The prevalence of IDA (IDE + hemoglobin < 110 g/L) was higher when accounting for than when disregarding inflammation (8.0% versus 6.2%, P = 0.083). Using sTfR and different SF cutoffs for children with versus without inflammation improved the diagnosis of iron depletion and IDE. Our results confirm that Inuit children are at particularly high risk for iron deficiency.