Physical Activity Among Immigrant Children: A Systematic Review.

BACKGROUND: The health benefits of physical activity (PA) for children are well documented. However, little is known about PA patterns among immigrant children. METHODS: The authors reviewed research on PA patterns of immigrant children. The inclusion criteria included peer-reviewed articles published from January 2010 to May 2018 in English, French, or Spanish that included primary-school-aged (6-12 y) children, and data on immigration status. RESULTS: A total of 11 articles were included in the analyses. These studies revealed a deficit of PA among immigrant children. Immigration status (immigrant or nonimmigrant) and generation of immigration (first, second, and third), ethnic origin, and gender were associated with PA patterns. In general, PA levels were lower among first-generation immigrant children, children of Hispanic and East Asian origin, and girls. The results suggest that questionnaire measures might be biased or inaccurate among immigrant children, highlighting the need for the integration of mixed methods (objective and subjective measures). CONCLUSIONS: A large proportion of children do not meet PA guidelines, and this might be more problematic for immigrant children. Future studies incorporating time since immigration, comparative analyses on gender, sociocultural and socioeconomic characteristics, and mixed methodology could provide a more complete portrait of PA patterns and opportunities for immigrant children.

Psychosocial Stress, Sedentary Behavior, and Physical Activity during Pregnancy among Canadian Women: Relationships in a Diverse Cohort and a Nationwide Sample.

BACKGROUND: Past research shows that psychosocial stress and distress predict sedentary behavior and physical activity, but few studies focus on pregnant women. Our objective was to analyze relationships between psychosocial stress and distress with sedentary behavior and physical activity among pregnant women in Canada. METHODS: We analyzed objectively-measured sedentary behavior and physical activity at 16-18, 24-26, and 32-24 weeks pregnancy in a sociodemographically diverse cohort of 70 women in Montreal, Canada. Participants completed the Perceived Stress Questionnaire and wore an accelerometer for 3 days that quantified sitting time and steps per day. We used univariate general linear models to analyze relationships between perceived stress with sedentary behavior and physical activity at each evaluation. To assess generalizability, we analyzed relationships between psychological distress with self-reported leisure-time sedentary behavior and daily energy expenditure in transportation and leisure physical activities among a sample representative of 166,095 women in the Canadian Community Health Survey. RESULTS: In the Montreal cohort, we observed a positive association between perceived stress and sitting time, with small to moderate effect sizes (partial η2 = 0.08-0.16). We observed negative relationships between perceived stress and steps per day at the first two evaluations only, with small to moderate effect sizes (partial η2 = 0.08-0.11). Relationships for sedentary behavior were similar in the nationwide sample, but with smaller effect sizes (partial η2 = 0.02). There were no relationships between distress and physical activity in the nationwide sample. CONCLUSION: Psychosocial stress represents one risk factor for sedentarity, with relationships evident throughout pregnancy and at the population level. Relationships with physical activity are less consistent, but stress might represent a risk factor for low physical activity in early to mid-pregnancy. Results might guide the development of more comprehensive interventions targeting stress, sedentarity, and physical activity. In particular, integrating psychosocial health into interventions to reduce sedentarity, and including concrete guidelines on sedentary behavior in psychosocial health interventions, might be prioritized.

Relationships between psychological distress and health behaviors among Canadian adults: Differences based on gender, income, education, immigrant status, and ethnicity.

OBJECTIVE: Psychosocial health predicts physical health outcomes in both clinical samples and the general population. One mechanism is through relationships with health behaviors. Results might differ based on sociodemographic characteristics such as education, income, ethnicity, and immigrant status. Our objective was to analyze sociodemographic differences in relationships between psychosocial health measures and health behaviors in the general population of Canadian adults. METHODS: We analyzed relationships between non-specific psychological distress, assessed using the Kessler-10 scale, and five key health behaviors: fruit and vegetable intake, screen sedentary behavior, physical activity, alcohol consumption, and cigarette use. Data were collected by Statistics Canada for the Canadian Community Health Survey in 2011-2014. Our sample included 54,789 participants representative of 14,555,346 Canadian adults. We used univariate general linear models on the weighted sample to analyze relationships between distress (predictor) and each health behavior, controlling for age. We entered sex and one of four sociodemographic variable of interest (education, income, ethnicity, immigrant status) into each model to analyze gender and sociodemographic differences in relationships. RESULTS: Greater distress predicted less fruit and vegetable intake and physical activity, and greater screen sedentary behavior and cigarette use, in the full sample, with small effect sizes (partial η2 up to 0.013). Differences by gender and sociodemographic characteristics were evident for all health behaviors. CONCLUSIONS: Psychosocial health might contribute to persistent socioeconomic disparities in health in part through relationships with health behaviors, although relationships in the general population are modest. Health behavior interventions incorporating psychosocial health might need to be tailored based on socioeconomic characteristics, and future research on intersections between multiple sociodemographic risk factors remains necessary.

Prenatal stress and child development: A scoping review of research in low- and middle-income countries.

INTRODUCTION: Past research has shown relationships between stress during pregnancy, and related psychosocial health measures such as anxiety and depressive symptoms, with infant, child, and adult outcomes. However, most research is from high-income countries. We conducted a scoping review to identify research studies on prenatal stress and outcomes of the pregnancy or offspring in low- and middle-income countries (LMICs), and to synthesize the stress measures and outcomes assessed, the findings observed, and directions for future research. METHODS: We searched PubMed, Scopus, and PsycINFO for English-language abstracts published from Jan 1960-Jan 2017. Search terms were related to stress and psychosocial health; pregnancy; infant or child development; and LMICs. RESULTS: 48 articles were identified. Sixty percent of studies were in upper-middle, 25% in lower-middle, and 15% in low income countries. Most studies used questionnaires, either existing or tailor-made, to assess stress. Eight assessed cortisol. Most studies (n = 31) assessed infant outcomes at birth, particularly gestational age or preterm birth (n = 22, 12 showing significant relationships), and birthweight (n = 21, 14 showing significant relationships). Five studies analyzed outcomes later in infancy such as temperament and motor development, all showing significant results; and nine in childhood such as behavioral development, asthma, and physical growth, with eight showing significant results. CONCLUSIONS: Results highlight the importance of prenatal stress on infant and child outcomes in LMICs. Methods used in high-income countries are successfully employed in LMICs, but tailored tools remain necessary. Careful assessment of covariates is needed to foster analyses of interactive effects and pathways. Studies including longer-term follow-up should be prioritized.

Perceptions of group exercise courses and instructors among Quebec adults.

BACKGROUND: Group exercise courses are popular among adults, but dropout rates are high. Studies of relationships between participants' perceptions and their participation might highlight factors to target to improve adherence and re-enrolment. METHODS: We used a mixed-methods approach to analyse perceptions of group exercise courses and instructors among 463 adults. Participants completed the Exercise Barriers and Benefits Scale, questionnaires on perceptions of the instructor and course, and non-participation. We assessed participation from weeks 2-4 and 5-10, and re-enrolment. We analysed relationships between perceptions and re-enrolment using linear regression and mediation analyses. We conducted group interviews with 11 participants. RESULTS: Predictors of re-enrolment included early participation (ß=0.11, P=0.029) and perceptions of the group social climate (P=0.027). Perceptions of the group mediated the relationship between early participation and re-enrolment (95% CI 0.0036 to 0.0471): early participation predicted more positive perceptions (ß=2.11, P=0.003), which predicted re-enrolment (ß=0.01, P=0.006). Qualitative analyses highlighted instructors' roles in promoting social exchange and integrating participants into the group. CONCLUSIONS: The social climate of group exercise courses is a key factor predicting re-enrolment. Early participation predicts re-enrolment on its own, and also promotes positive perceptions of the group. Instructors can target these factors by sensitising participants to the importance of early participation, and promoting social exchange.

Behavioral risk factors for obesity during health transition in Vanuatu, South Pacific.

UNLABELLED: The South Pacific archipelago of Vanuatu, like many developing countries, is currently experiencing a shift in disease burdens from infectious to chronic diseases with economic development. A rapid increase in obesity prevalence represents one component of this "health transition." OBJECTIVE: To identify behaviors associated with measures of obesity in Vanuatu. DESIGN AND METHODS: Five hundred and thirty four adults from three islands varying in level of economic development were surveyed. Height, weight, waist, and hip circumferences; triceps, subscapular and suprailiac skinfolds; and percent body fat (%BF) by bioelectrical impedance were measured. Diet through 24-h dietary recall and physical activity patterns using a survey were assessed. We analyzed prevalence of obesity and central obesity based on multiple indicators (body mass index, %BF, waist circumference, and waist-to-height ratio), and analyzed differences among islands and associations with behavioral patterns. RESULTS: Obesity prevalence was lowest among rural and highest among suburban participants. Prevalence of central obesity was particularly high among women (up to 73.9%), even in rural areas (ranging from 14.7 to 41.2% depending on the measure used). Heavier reliance on animal protein and incorporation of Western foods in the diet-specifically, tinned fish and instant noodles-was significantly associated with increased obesity risk. CONCLUSIONS: Even in rural areas where diets and lifestyles remain largely traditional, modest incorporation of Western foods in the diet can contribute to increased risk of obesity. Early prevention efforts are thus particularly important during health transition. Where public health resources are limited, education about dietary change could be the best target for prevention.

Brief communication: prenatal and early postnatal stress exposure influences long bone length in adult rat offspring.

Stress during the prenatal and early postnatal periods (perinatal stress, PS) is known to impact offspring cognitive, behavioral, and physical development, but effects on skeletal growth are not clear. Our objective was to analyze effects of variable, mild, daily PS exposure on adult offspring long bone length. Twelve pregnant rat dams were randomly assigned to receive variable stress from gestational days 14-21 (Prenatal group), postpartum days 2-9 (Postnatal), both periods (Pre-Post), or no stress (Control). Differences in adult offspring tibia and femur length were analyzed among treatment groups. Mean tibia length differed among groups for males (P = 0.016) and females (P = 0.009), and differences for femur length approached significance for males (P = 0.051). Long bone length was shorter among PS-exposed offspring, especially those exposed to postnatal stress (Postnatal and Pre-Post groups). Results persisted when controlling for nose-tail length. These differences might reflect early stunting that is maintained in adulthood, or delayed growth among PS-exposed offspring. This study suggests that PS results in shorter long bones in adulthood, independently of effects on overall body size. Stunting and growth retardation are major global health burdens. Our study adds to a growing body of evidence suggesting that PS is a risk factor for poor linear growth.

Prenatal exposure to a natural disaster increases risk for obesity in 5½-year-old children.

INTRODUCTION: An adverse environment in utero, including exposure to prenatal maternal stress (PNMS), can result in poor birth outcomes such as low birth weight, which increases risk of later cardiometabolic diseases such as hypertension and obesity. It is unclear to what extent PNMS influences obesity risk independent of its impact on birth characteristics, especially among humans. Our objective was to determine whether PNMS resulting from a natural disaster influenced risk of childhood obesity. RESULTS: Eight children with high objective PNMS exposure (14.5%) were obese compared to one child (1.8%) with low exposure (P = 0.02). Objective PNMS increased obesity risk (model 1, P = 0.02, odds ratio = 1.37) after controlling for other potential risk factors. DISCUSSION: Results suggest that PNMS might be an independent risk factor in the development of childhood obesity. METHODS: Participants included 111 women who were pregnant during the January 1998 Québec Ice Storm or who conceived within the following 3 months and their children. We tested associations between objective and subjective PNMS from the storm and childhood obesity status at age 5½, controlling for children's birth characteristics and breastfeeding status; household socioeconomic status; maternal obstetric complications, life events and smoking during pregnancy, psychological functioning, and height (model 1, n = 111) or BMI (for a subset of 69 participants, model 2).

Behavioral changes associated with economic development in the South Pacific: health transition in Vanuatu.

UNLABELLED: Health patterns are changing in developing countries; as diet and activity patterns change with economic development, chronic disease prevalence increases, which is a characteristic of health transition. The islands of Vanuatu (South Pacific) have varying rates of economic development and provide a natural experimental model of health transition. OBJECTIVES: To characterize behavioral changes associated with modernization. METHODS: We surveyed 425 children and 559 adults on three islands varying in degree of economic development. We assessed diet (24-h dietary recall), physical activity (mode of transport, work activities, and recreation), substance use, and other behavioral patterns. RESULTS: Spending patterns and access to Western foods followed modernization gradients in our sample, whereas occupational patterns and ownership of technological goods were poor markers of modernization. With increasing economic development, participants consumed more animal proteins and simple carbohydrates. Physical activity levels were high; most participants were active in gardening, and sports were popular, especially in urban areas. However, urban participants spent more time in sedentary recreation. Men's use of alcohol and tobacco increased with economic development, but we observed marked differences in substance use patterns between two rural islands-one with and one without tourism. CONCLUSIONS: Economic development in Vanuatu is accompanied by nutrition transition and increased sedentary recreation, although physical activity levels remain high. Differences in substance use patterns between rural islands with and without tourism indicate a need for more research in rural areas. These findings might inform research in other communities in the early stages of health transition.

Characterizing genetic diversity of contemporary pacific chickens using mitochondrial DNA analyses.

BACKGROUND: Mitochondrial DNA (mtDNA) hypervariable region (HVR) sequences of prehistoric Polynesian chicken samples reflect dispersal of two haplogroups--D and E--by the settlers of the Pacific. The distribution of these chicken haplogroups has been used as an indicator of human movement. Recent analyses suggested similarities between prehistoric Pacific and South American chicken samples, perhaps reflecting prehistoric Polynesian introduction of the chicken into South America. These analyses have been heavily debated. The current distribution of the D and E lineages among contemporary chicken populations in the Western Pacific is unclear, but might ultimately help to inform debates about the movements of humans that carried them. OBJECTIVES: We sought to characterize contemporary mtDNA diversity among chickens in two of the earliest settled archipelagos of Remote Oceania, the Marianas and Vanuatu. METHODS: We generated HVR sequences for 43 chickens from four islands in Vanuatu, and for 5 chickens from Guam in the Marianas. RESULTS: Forty samples from Vanuatu and three from Guam were assigned to haplogroup D, supporting this as a Pacific chicken haplogroup that persists in the Western Pacific. Two haplogroup E lineages were observed in Guam and two in Vanuatu. Of the E lineages in Vanuatu, one was identical to prehistoric Vanuatu and Polynesian samples and the other differed by one polymorphism. Contrary to our expectations, we observed few globally distributed domesticate lineages not associated with Pacific chicken dispersal. This might suggest less European introgression of chickens into Vanuatu than expected. If so, the E lineages might represent lineages maintained from ancient Pacific chicken introductions. The Vanuatu sample might thus provide an opportunity to distinguish between maintained ancestral Pacific chicken lineages and replacement by global domesticates through genomic analyses, which could resolve questions of contemporary haplogroup E chicken relationships and inform interpretations of debated sequences from archaeological samples.

Relationships between body size and percent body fat among Melanesians in Vanuatu.

Obesity is a global epidemic, and measures to define it must be appropriate for diverse populations for accurate assessment of worldwide risk. Obesity refers to excess body fatness, but is more commonly defined by body mass index (BMI). Body composition varies among populations: Asians have higher percent body fat (%BF), and Pacific Islanders lower %BF at a given BMI compared to Europeans. Many researchers thus propose higher BMI cut-off points for obesity among Pacific Islanders and lower cut-offs for Asians. Because of the great genetic diversity in the Asia-Pacific region, more studies analyzing associations between BMI and %BF among diverse populations remain necessary. We measured height; weight; tricep, subscapular, and suprailiac skinfolds; waist and hip circumference; and %BF by bioelectrical impedance among 546 adult Melanesians from Vanuatu in the South Pacific. We analyzed relationships among anthropometric measurements and compared them to measurements from other populations in the Asia-Pacific region. BMI was a relatively good predictor of %BF among our sample. Based on regression analyses, the BMI value associated with obesity defined by %BF (>25% for men, >35% for women) at age 40 was 27.9 for men and 27.8 for women. This indicates a need for a more nuanced definition of obesity than provided by the common BMI cut-off value of 30. Rather than using population-specific cut-offs for Pacific Islanders, we suggest the World Health Organization's public health action cut-off points (23, 27.5, 32.5, 37.5), which enhance the precision of assessments of population-wide obesity burdens while still allowing for international comparison.

Chronic radiation exposure in the Rivne-Polissia region of Ukraine: implications for birth defects.

OBJECTIVES: The health effects of chronic low-dose radiation exposure remains a controversial question. Monitoring after the Chernobyl nuclear accident in Ukraine suggested that chronic low-dose radiation exposure was not linked to cancer mortality among the general population. However, elevated rates of birth defects in contaminated compared to uncontaminated regions suggest that exposure to radiation in utero might impact development and that chronic radiation exposure might represent an underestimated risk to human health. METHODS: We sought to determine current radiation exposure routes in Rivne-Polissia, a region of Ukraine contaminated by the Chernobyl accident. This represents a first step toward comprehensive studies of the effects of chronic radiation exposure on human health. We designed and administered a dietary and activity survey to 344 women in Polissia. We assessed types and sources of food consumed, types of outdoor activities, and alcohol intake. RESULTS: Alcohol intake was low and alone does not account for the observed high rates of birth defects. Wild foods, especially mushrooms and berries, and locally produced foods, especially milk related, were major radiation exposure routes. Additionally, women were exposed to radiation through inhalation while burning grasses and potato vines in fields, and wood for cooking and heating. CONCLUSIONS: Twenty four years after the Chernobyl accident, women continue to be chronically exposed to low-dose radiation at levels exceeding current recommendations. This might contribute (especially synergistically with alcohol consumption and micronutrient deficiencies) to higher prevalence of birth defects in areas of Ukraine with high levels of radiation contamination compared to uncontaminated areas.

Beer is the cattle of women: sorghum beer commercialization and dietary intake of agropastoral families in Karamoja, Uganda.

Karimojong agropastoralists of Uganda have employed a dual subsistence strategy of cattle herding and sorghum cultivation to survive in an unpredictable environment, one afflicted by a severe humanitarian crisis. Armed raiding since the 1970s has led to devastating cattle losses, high male mortality, and increased sedentarization of women and children in densely populated homesteads, where infectious diseases and malnutrition rates are prevalent. Fieldwork in 1998-1999 confirmed the detrimental effects of armed raiding on child growth and development. During this period, however, women maintained largely traditional subsistence patterns. Follow-up fieldwork in 2004 revealed surprising subsistence changes: sorghum beer, an important food and ritual item, was being brewed for sale, which had not been noted in previous literature on the Karimojong. We outline the role of beer in the diet by analyzing the nutritional profile of Karimojong women and children, nutrients supplied by beer, and those supplied by foodstuffs purchased with sales profits. Commercial beer supplied from 3 to 6% of energy intake, and grains leftover from brewing (dregs) supplied from 3 to 12%. Selling beer was women's preferred form of casual labor, with differing patterns of participation in brewing between rural and peri-urban areas. Women who were paid in currency relied on profits to purchase nutrient-rich supplemental foodstuffs important in an otherwise marginal diet, as well as beer. The households of women who worked for other brewers or purchased beer wholesale and sold it retail relied heavily on dregs for daily subsistence. Nutrient intake was highest among women with cattle and sorghum who brewed and sold beer from their homesteads, and lowest among women who lacked sorghum and worked for commercial brewers in urban centers. Because nutritional status remains marginal in Karamoja, beer commercialization as a consequence of subsistence changes could have dramatic health consequences for women and children.

Origins of the Moken Sea Gypsies inferred from mitochondrial hypervariable region and whole genome sequences.

The origins of the Moken 'Sea Gypsies,' a group of traditionally boat-dwelling nomadic foragers, remain speculative despite previous examinations from linguistic, sociocultural and genetic perspectives. We explored Moken origin(s) and affinities by comparing whole mitochondrial genome and hypervariable segment I sequences from 12 Moken individuals, sampled from four islands of the Mergui Archipelago, to other mainland Asian, Island Southeast Asian (ISEA) and Oceanic populations. These analyses revealed a major (11/12) and a minor (1/12) haplotype in the population, indicating low mitochondrial diversity likely resulting from historically low population sizes, isolation and consequent genetic drift. Phylogenetic analyses revealed close relationships between the major lineage (MKN1) and ISEA, mainland Asian and aboriginal Malay populations, and of the minor lineage (MKN2) to populations from ISEA. MKN1 belongs to a recently defined subclade of the ancient yet localized M21 haplogroup. MKN2 is not closely related to any previously sampled lineages, but has been tentatively assigned to the basal M46 haplogroup that possibly originated among the original inhabitants of ISEA. Our analyses suggest that MKN1 originated within coastal mainland SEA and dispersed into ISEA and rapidly into the Mergui Archipelago within the past few thousand years as a result of climate change induced population pressure.