Association between age at menarche and cardiometabolic risk among Samoan adults.

OBJECTIVES: Recent studies suggest that early menarche may increase cardiometabolic morbidity and mortality. Yet few studies have examined this association in the Pacific Islands, where obesity prevalence is among the highest globally. We sought to examine associations between age at menarche and cardiometabolic risk in Samoa. METHODS: Participants were from the Soifua Manuia study (n = 285, age 32-72 years) conducted in Samoa from 2017 to 2019. Logistic regressions were conducted to estimate odds of obesity, hypertension, diabetes, dyslipidemia, and metabolic syndrome per one-year increase in age at menarche. Linear regressions were conducted to examine associations between age at menarche and continuous measures of adiposity, blood pressure, insulin resistance, and serum lipids. RESULTS: Median age at menarche was 14 years (IQR = 2). After controlling for relevant covariates, each one-year increase in age at menarche was associated with a 15% decrease (OR = 0.85, 95% CI: 0.72-1.01, p = .067) in odds of hypertension, but a 21% increase (OR = 1.21, 95% CI: 1.01-1.45, p = .044) in odds of diabetes and 18% increase (OR = 1.18, 95% CI: 0.98-1.42, p = .081) in odds of high total cholesterol. Each additional year in age at menarche was associated with a 1.60 ± 0.52 kg (p = .002) decrease in lean mass and 1.56 ± 0.51 kg (p = .003) decrease in fat-free mass. CONCLUSIONS: Associations between age at menarche and cardiometabolic risk may be population-specific and are likely influenced by both current and historical nutritional and epidemiological contexts. Prospective studies are needed to clarify the role of childhood adiposity and other early life exposures on age at menarche and subsequent cardiometabolic risk.

Validity of anthropometric equation-based estimators of fat mass in Samoan adults.

INTRODUCTION: In 1999, a set of highly accurate Polynesian-specific equations to estimate adult body fat from non-invasive field measures of age, sex, height, and weight (Equation 1), age, sex, height, weight, and bioelectrical impedance analysis (BIA) resistance (Equation 2), and age, sex, height, weight, and the sum of two skinfold thicknesses (Equation 3) were published. The purpose of this study was to evaluate the performance of the equation-based estimators in a sample of Samoan adults recruited 20 years later between 2017 and 2019. METHODS: Age, sex, height, weight, BIA resistance, skinfold thickness, and fat mass as measured using dual energy x-ray absorptiometry (DXA) were available for 432 Samoan adults (mean age 50.9 years, 56% female) seen in 2017/2019. We compared equation-derived fat mass and DXA-derived fat mass using scatterplots and Pearson correlation coefficients. We then updated the equation coefficient estimates in a training set (2/3 of the sample) and evaluated the performance of the updated equations in a testing set (the remaining 1/3 of the sample). RESULTS: Equation-derived fat mass was strongly correlated with DXA-derived fat mass for Equation (1) (r2  = 0.95, n = 432), Equation (2) (r2  = 0.97, n = 425), and Equation (3) (r2  = 0.95, n = 426). Updating the equation coefficient estimates resulted in mostly similar coefficients and nearly identical testing set performance for Equation (1) (r2  = 0.96, n = 153), Equation (2) (r2  = 0.98, n = 150), and Equation (3) (r2  = 0.96, n = 150). CONCLUSIONS: The Polynesian-specific body fat estimation equations remained stable despite changing social and environmental factors and marked increase in obesity prevalence in Samoa.

Prevalence of malnutrition among Samoan children aged 5 to 11 years in 2019-2020.

BACKGROUND: Globally, rapid economic development, urbanisation, and nutrition transitions have led to rising levels of malnutrition in all forms. AIM: The study objective was to document the prevalence of overweight/obesity, underweight, stunting, and anaemia among Samoan children in 2019-2020. SUBJECTS AND METHODS: Children from the Ola Tuputupua'e "Growing Up" in Samoa study at ages 5-11 years with complete physical assessments were included. Overweight/obesity, underweight, and stunting were classified using World Health Organisation Z-scores for body mass index-for-age (BMIZ> +1), weight-for-age (WAZ< -2SD), and height-for-age (HAZ< -2SD), respectively. Anaemia was defined as haemoglobin concentration <11.5 g/dL. Prevalence was compared by child age, sex, and census region of residence (representing urbanicity and exposure to nutrition transition) using Wilcoxon two-sample, Chi-square, or Fisher's exact tests. RESULTS: The prevalence of overweight/obesity, underweight, stunting, and anaemia was 36.2%, 0.5%, 1.6%, and 31.6%, respectively. Overweight/obesity in children was positively associated with age and highly prevalent in periurban and urban regions. While children living in the rural region with the lowest exposure to nutrition transition had the highest prevalence of mild-to-moderate stunting, anaemia prevalence was lower compared to those in the urban region. No sex differences in malnutrition were observed. CONCLUSION: Moderate-to-high levels of overweight/obesity and anaemia call for comprehensive intervention strategies.

Accelerometer-based osteogenic indices, moderate-to-vigorous and vigorous physical activity, and bone traits in adolescents.

OBJECTIVES: We investigated the associations of accelerometry-derived osteogenic indices (OIs), moderate-to-vigorous (MVPA), and vigorous intensity physical activity (VPA) with peripheral quantitative computed tomography (pCQT) parameters in 99 adolescents aged 10-13 years. METHODS: Bone parameters were assessed at the distal (4%) and shaft (66%) of the tibia using pQCT. Accelerometers were worn on the right hip for 7 consecutive days. OIs were calculated based on acceleration peak histograms either using all of the peaks (OI) or peaks with acceleration ≥5.2 g (HOI). MVPA and VPA were defined using previously published cut-points. RESULTS: HOI was positively associated with total area (Partial correlation= 0.22, 95% CI=0.01 to 0.41), cortical area (CoA) (0.33, 95% CI=0.13 to 0.50), and stress strain index (SSI) (0.29, 95% CI=0.09 to 0.47) of tibial shaft and with total density at the distal tibia (0.23, 95% CI=0.02 to 0.42). OI was positively associated with CoA (0.31, 95% CI=0.11 to 0.49) and SSI (0.26, 95% CI=0.05 to 0.44) of tibial shaft. MVPA was positively associated with CoA (0.28, 95% CI=0.07 to 0.46) of the tibial shaft. CONCLUSIONS: OI and HOI were positively associated with pQCT parameters while MVPA and VPA demonstrated less consistent associations with them.

C-reactive protein in adult Samoans: Population variation and physiological correlates.

OBJECTIVES: C-reactive protein (CRP) has been associated with adiposity and cardiometabolic disease risk in many populations but remains remarkably understudied in Pacific Islander populations. Here, we provide the first examination of correlates of CRP in adult Samoans (n = 108, ages 35-55 years) to test the hypotheses that CRP exhibits sex-dependent associations with measures of BMI, adiposity, and cardiometabolic disease risks. METHODS: We analyzed associations between measures of adiposity (total fat mass, visceral fat mass, percent total body fat), body mass index (BMI), cardiometabolic risks, behaviors, demographics, and CRP. Unadjusted analyses of CRP were undertaken using Pearson's pairwise, and Spearman's rank correlations; one-way analysis of variance and Kruskal-Wallis tests assessed variables by CRP quartiles. Adjusted analyses of CRP correlates were examined using generalized linear regression. RESULTS: Serum CRP ranged from 0.08 to 13.3 mg/L (median 1.4 mg/L) and varied significantly by sex t (108) = -2.47, p = .015. CRP was weakly to moderately associated with measures of adiposity and BMI (r and ρ ranged between 0.25 and 0.50, p < .05) and some cardiometabolic markers (including HbA1c, fasting insulin, and insulin resistance). CRP was significantly associated with percent body fat in women and men, adjusting for other variables. CONCLUSIONS: These data are among the first to demonstrate CRP correlates in a sample of adult Samoans. CRP differed by sex and was associated with BMI, adiposity, and some cardiometabolic risk markers. These data align with findings in other populations.

Persistence of anaemia among Samoan preschool age children: a longitudinal study.

OBJECTIVE: To characterise the prevalence and persistence of anaemia among Samoan children over a 2-3-year period. DESIGN: Data were from two consecutive waves (2015 and 2017-2018) of the Ola Tuputupua'e 'Growing up' study. Anaemia (Hb < 11·0 or 11·5 g/dl for 2-4 and ≥ 5 years old, respectively) was considered 'transient' when it occurred at only one wave or 'persistent' if it was present at two consecutive waves. Child, maternal and household correlates of anaemia were examined using log-binomial and modified Poisson regressions. SETTING: Eleven Samoan villages. PARTICIPANTS: Mother-child pairs (n 257) recruited in 2015 and reassessed in 2017-2018. RESULTS: Anaemia prevalence was 33·9 % in 2015 and 28·0 % in 2017-2018; 35·6 % of cases identified in 2015 were persistent. Risk of anaemia at only one wave was lower among children who were older in 2015 (age 4 v. 2 years, adjusted relative risk (aRR) = 0·54, (95 % CI 0·35, 0·84), P = 0·007), had older mothers (≥ 40 v. 18-29 years, aRR = 0·61, (95 % CI 0·39, 0·95), P = 0·029) and had higher daily sodium intake (for every 100 mg/d, aRR = 0·97, (95 % CI 0·95, 0·99), P = 0·003) than children with no anaemia. Children whose anaemia persisted were more likely to have had a mother with anaemia (aRR = 2·13, (95 % CI 1·17, 3·89), P = 0·013) and had higher daily dietary iron intake (for every 10 mg/d, aRR = 4·69, (95 % CI 1·33, 16·49), P = 0·016) than those with no anaemia. CONCLUSIONS: Alongside broadly targeted prevention efforts, which are warranted given the moderate-high anaemia prevalence observed, specific attention should be paid to children with risk factors for persistent anaemia. Routine screening of children whose mothers have anaemia should be encouraged.

Development of a Parkinson's disease specific falls questionnaire.

BACKGROUND: Falls are a major health burden for older adults with Parkinson's disease (PD), but there is currently no reliable questionnaire to capture the circumstances and consequences of falls in older adults with PD. This study aimed to develop a PD-specific falls questionnaire and to evaluate its test-retest reliability in older adults with PD. METHODS: A novel PD-specific falls questionnaire (PDF-Q) was developed in two modes (online and paper-based version) and used to assess falls and near-falls events over the past 12-months. Questions were agreed upon by an expert group, with the domains based on previous falls-related questionnaires. The questions included the number and circumstances (activities, location and direction) of falls and near-falls, and consequences (injuries and medical treatment) of falls. The PDF-Q was distributed to 46 older adults with PD (online n = 30, paper n = 16), who completed the questionnaire twice, 4 weeks apart. Kappa (κ) statistics were used to establish test-retest reliability of the questionnaire items. RESULTS: Pooled results from both questionnaires for all participants were used to assess the overall test-retest reliability of the questionnaire. Questions assessing the number of falls (κ = 0.41) and the number of near-falls (κ = 0.51) in the previous 12-months demonstrated weak agreement, while questions on the location of falls (κ = 0.89) and near-falls (κ = 1.0) demonstrated strong to almost perfect agreement. Questions on the number of indoor (κ = 0.86) and outdoor (κ = 0.75) falls demonstrated moderate to strong agreement, though questions related to the number of indoor (κ = 0.47) and outdoor (κ = 0.56) near-falls demonstrated weak agreement. Moderate to strong agreement scores were observed for the most recent fall and near-fall in terms of the direction (indoor fall κ = 0.80; outdoor fall κ = 0.81; near-fall κ = 0.54), activity (indoor fall κ = 0.70; outdoor fall κ = 0.82; near-fall κ = 0.65) and cause (indoor fall κ = 0.75; outdoor fall κ = 0.62; near-fall κ = 0.56). CONCLUSIONS: The new PDF-Q developed in this study was found to be reliable for capturing the circumstances and consequences of recent falls and near-falls in older adults with PD.

The skeletal maturity of Australian children aged 10-13 years in 2016.

Skeletal maturity can be used as a biological indicator of the tempo of growth in children and adolescents. We present a description of skeletal maturity from a cohort of white Australian children and describe variation in skeletal maturity based on child age. Participants (n = 71; age 10.5-13.9 years) were recruited from the 'Healthy, Active Preschool & Primary Years (HAPPY)' study. Left hand-wrist radiographs were used to determine skeletal maturity using the Tanner-Whitehouse III (TW3) RUS technique. In boys, the mean skeletal maturity offset (bone age - chronological age) was -0.12 ± 0.19 years and 57.9% had delayed skeletal maturity compared to chronological age. Among those with delayed skeletal maturity, the average delay was 0.99 years (range 0.02-2.54 years). In girls, skeletal age was advanced, on average, compared to chronological age by 0.32 ± 0.20 years. Among the 39.4% of girls with delayed skeletal maturity, the average delay was 0.48 years (range: 0.01-2.28). Four children in the sample exhibited a delay in skeletal maturity greater than 2 years. In the context of secular trends towards advanced skeletal maturity observed globally, delayed skeletal maturation in this white, economically privileged cohort are surprising and warrant further exploration.

Body size and composition of Samoan toddlers aged 18-25 months in 2019.

BACKGROUND: The "Foafoaga O le Ola (Beginning of Life)" study is a prospective birth cohort of n = 160 Samoan mother-infant dyads established in 2017-2018. A primary study aim is to explore how a missense variant at CREBRF rs373863828 impacts growth in early life, given its association with increased body size but lower risk of diabetes in adult Samoans. Here, we examine body size and composition by genotype among toddlers aged 18.7-24.5 months. METHODS: Height, weight, head circumference, mid-upper-arm circumference, and abdominal circumference, as well as subscapular, triceps, iliac crest and thigh skinfold thickness were measured among 107 toddlers with known rs373863828 genotype; 42 of these toddlers completed dual-energy X-ray absorptiometry (DXA) scans from which body composition (total body less head fat mass, lean mass, bone mass, % fat mass and % fat-free mass) was estimated. RESULTS: After controlling for sex and age, toddlers with at least one copy of the CREBRF minor allele (AA/AG) were 1.31 cm taller (SE = 0.64, p = 0.045) than toddlers with the GG genotype. CONCLUSION: Whether greater linear growth in early childhood could contribute to the metabolically protective effects associated with the CREBRF variant in adulthood should be explored in future studies.

The Association Between Muscle Mass and Strength in Relation to Bone Measures in a Paediatric Population: Sex-Specific Effects.

Post-puberty, bone mass displays clear sex-specific patterns. However, research has suggested that a sexual dimorphism in bone mass is evident in younger children and is likely attributable to differences in lean mass. Thus, we aimed to determine whether the association with both overall muscle mass and/or muscle strength was different between the sexes in a paediatric population. Participants were recruited as part of the Vitamin D in Pregnancy Study, Australia. There were 209/402 (52.3%) children at the 11-year follow-up, and 172 had complete data. Children were assessed for bone mineral content (BMC), bone mineral density (BMD) and lean mass by DXA (Lunar). Handgrip strength (kg) was measured using a dynamometer (JAMAR). Linear regression models were adjusted for height, weight, age and pubertal stage. In adjusted models, including both muscle strength and lean mass, the observed association differed between boys and girls. At the spine in boys, BMC and BMD were associated with muscle strength (ß 0.34 [95%CI 0.09-0.59] and 0.008 [95%CI 0.003-0.014]; respectively) but not total muscle mass. However, muscle mass was associated with BMC and BMD at the total body (less head). In girls, spine BMC and BMD were associated with total lean mass (ß 0.95 [95%CI 0.61-1.3] and ß 0.01 [95%CI 0.005-0.02], respectively), with a similar pattern of association with total body (less head) measures. Muscle mass and strength appear to have sexually dimorphic effects on bone mass in school-aged children. These findings should be replicated in longitudinal studies.

Prospective associations with physiological, psychosocial and educational outcomes of meeting Australian 24-Hour Movement Guidelines for the Early Years.

BACKGROUND: Several countries have released movement guidelines for children under 5 that incorporate guidelines for sleep, physical activity and sedentary behavior. This study examines prospective associations of preschool children's compliance with the 24-Hour Australian movement guidelines (sleep, physical activity, screen time) and physiological, psychosocial and educational outcomes during primary school. METHODS: Data were from the Healthy Active Preschool and Primary Years Study (Melbourne, Australia; n = 471; 3-5 years; 2008/9). Follow-ups occurred at 3 (2011/12; 6-8 years), 6 (2014/15; 9-11 years) and 7 (2016; 10-12 years) years post baseline. Multiple regression models assessed associations between compliance with guidelines at baseline and later outcomes. RESULTS: Children were 4.6 years at baseline (53% boys; 62% high socio-economic families). Most children met physical activity (89%) and sleep (93%) guidelines; 23% met screen-time guidelines; and 20% met all guidelines at baseline. Meeting all of the three guidelines was associated with lower BMI z-scores at 9-11 years of age (b = - 0.26, 95%CI -0.47, - 0.05). Meeting physical activity guidelines was associated with higher total body bone mineral density (b = 0.64, 95%CI 0.15, 1.13), and total body bone mineral content (b = 183.19, 95%CI 69.92, 296.46) at 10-12 years of age. Meeting sleep guidelines was associated with better reading (b = 37.60, 95%CI 6.74, 68.46), spelling (b = 34.95, 95%CI 6.65, 63.25), numeracy (b = 39.09, 95%CI 11.75, 66.44), language (b = 44.31, 95%CI 11.77, 76.85) and writing (b = 25.93, 95%CI 0.30, 51.57) at 8-9 years of age. No associations were evident for compliance with screen-time guidelines or for psychosocial outcomes. CONCLUSIONS: Compliance with different movement behavior guidelines was associated with different outcomes. Strategies to support children in meeting all of the guidelines are warranted to maximize health and educational outcomes. Future research investigating dose-response associations, and potential mechanisms, is necessary.

Effect of maternal nutrient intake during 31-37 weeks gestation on offspring body composition in Samoa.

BACKGROUND: Pregnancy dietary intake may be associated with newborn body composition, a predictor of future obesity. In Samoa, an energy-dense diet contributes to an alarming prevalence of adult obesity. Identifying associations between pregnancy nutrition and infant body composition in this setting may guide strategies to mitigate intergenerational transmission of obesity risk. AIM: To examine dietary macro- and micronutrient intake of Samoan women during the third trimester of pregnancy and associations with infant body composition. SUBJECTS AND METHODS: At 34-41 weeks of gestation, we measured dietary intake from the prior month using a Food Frequency Questionnaire (FFQ). Dual-energy X-ray absorptiometry (DXA) measured infant body composition at 1-14 days. We used multivariable linear regression models accounting for confounders to identify independent effects of nutrient intake on infant body composition. RESULTS: After adjusting for maternal body mass index, age, gravidity, infant age, and sex, a respective 0.2 g increase and 0.2 g decrease in infant bone mass was associated with fibre and saturated fat intake. Increased protein intake was associated with 0.02 g decrease in bone mass. CONCLUSIONS: While maternal dietary intake was not associated with infant adiposity or lean mass, we observed an effect on bone mass whose role in regulating metabolic health is overlooked.

Circulating Levels of Inflammation and the Effect on Exercise-Related Changes in Bone Mass, Structure and Strength in Middle-Aged and Older Men.

Chronic, low-grade systematic inflammation has been associated with bone loss and increased fracture risk. We previously reported that exercise improved femoral neck bone mineral density (BMD), geometry and strength and lumbar spine trabecular BMD in middle-aged and older men, but had no effect on markers of inflammation. The aim of this study was to examine the association between basal inflammatory status and the adaptive skeletal responses to exercise. Secondary analysis was completed on 91 men aged 50-79 years who participated in an 18-month program of progressive resistance training plus weight-bearing impact exercise (3 day/week) with and without additional calcium-vitamin D3. Markers of inflammation (serum hs-CRP, TNF-α and IL-6) and DXA and QCT-derived BMD, bone structure and strength at the lumbar spine and proximal femur were measured at baseline and 18 months. Multiple regression was used to assess associations between skeletal changes and both baseline levels of individual inflammatory markers and a composite inflammatory index derived from the number of markers categorized into the highest tertile. Baseline serum hs-CRP, TNFα and IL-6 and the composite inflammatory index score were not associated with skeletal changes at any site after adjusting for age, change in lean mass, disease(s)/medication use and adherence to the exercise intervention. In conclusion, this study indicates that basal inflammatory status does not influence the osteogenic response to exercise training in healthy middle-aged and older men.

Strategies and challenges associated with recruiting retirement village communities and residents into a group exercise intervention.

BACKGROUND: Randomized controlled trials (RCTs) provide the highest level of scientific evidence, but successful participant recruitment is critical to ensure the external and internal validity of results. This study describes the strategies associated with recruiting older adults at increased falls risk residing in retirement villages into an 18-month cluster RCT designed to evaluate the effects of a dual-task exercise program on falls and physical and cognitive function. METHODS: Recruitment of adults aged ≥65 at increased falls risk residing within retirement villages (size 60-350 residents) was initially designed to occur over 12 months using two distinct cohorts (C). Recruitment occurred via a three-stage approach that included liaising with: 1) village operators, 2) independent village managers, and 3) residents. To recruit residents, a variety of different approaches were used, including distribution of information pack, on-site presentations, free muscle and functional testing, and posters displayed in common areas. RESULTS: Due to challenges with recruitment, three cohorts were established between February 2014 and April 2015 (14 months). Sixty retirement villages were initially invited, of which 32 declined or did not respond, leaving 28 villages that expressed interest. A total of 3947 individual letters of invitation were subsequently distributed to residents of these villages, from which 517 (13.1%) expressions of interest (EOI) were received. Across three cohorts with different recruitment strategies adopted there were only modest differences in the number of EOI received (10.5 to 15.3%), which suggests that no particular recruitment approach was most effective. Following the initial screening of these residents, 398 (77.0%) participants were deemed eligible to participate, but a final sample of 300 (58.0% of the 517 EOI) consented and was randomized; 7.6% of the 3947 residents invited. Principal reasons for not participating, despite being eligible, were poor health, lack of time and no GP approval. CONCLUSION: This study highlights that there are significant challenges associated with recruiting sufficient numbers of older adults from independent living retirement villages into an exercise intervention designed to improve health and well-being. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry: ACTRN12613001 161718 . Date registered 23rd October 2013.

Dietary patterns are associated with child, maternal and household-level characteristics and overweight/obesity among young Samoan children.

OBJECTIVE: Among young Samoan children, diet may not be optimal: in 2015, 16·1 % of 24-59-month-olds were overweight/obese, 20·3 % stunted and 34·1 % anaemic. The present study aimed to identify dietary patterns among 24-59-month-old Samoan children and evaluate their association with: (i) child, maternal and household characteristics; and (ii) nutritional status indicators (stunting, overweight/obesity, anaemia). DESIGN: A community-based, cross-sectional study. Principal component analysis on 117 FFQ items was used to identify empirical dietary patterns. Distributions of child, maternal and household characteristics were examined by factor score quintiles. The regression of nutritional status indicators v. these quintiles was performed using logistic regression models. SETTING: Ten villages on the Samoan island of Upolu. SUBJECTS: A convenience sample of mother-child pairs (n 305). RESULTS: Two dietary patterns, modern and neo-traditional, emerged. The modern pattern was loaded with 'westernized' foods (red meat, condiments and snacks). The neo-traditional pattern included vegetables, local starches, coconuts, fish and poultry. Following the modern diet was associated with urban residence, greater maternal educational attainment, higher socio-economic status, lower vitamin C intake and higher sugar intake. Following the neo-traditional diet was associated with rural residence, lower socio-economic status, higher vitamin C intake and lower sugar intake. While dietary patterns were not related to stunting or anaemia, following the neo-traditional pattern was positively associated with child overweight/obesity (adjusted OR=4·23, 95 % CI 1·26, 14·17, for the highest quintile, P-trend=0·06). CONCLUSIONS: Further longitudinal monitoring and evaluation of early childhood growth and development are needed to understand the influences of early diet on child health in Samoa.

Validity of hip-worn inertial measurement unit compared to jump mat for jump height measurement in adolescents.

Jump tests assess lower body power production capacity, and can be used to evaluate athletic ability and development during growth. Wearable inertial measurement units (IMU) seem to offer a feasible alternative to laboratory-based equipment for jump height assessments. Concurrent validity of these devices for jump height assessments has only been established in adults. Therefore, the purpose of this study was to evaluate the concurrent validity of IMU-based jump height estimate compared to contact mat-based jump height estimate in adolescents. Ninety-five adolescents (10-13 years-of-age; girls N = 41, height = 154 (SD 9) cm, weight = 44 (11) kg; boys N = 54, height = 156 (10) cm, weight = 46 (13) kg) completed 3 counter-movement jumps for maximal jump height on a contact mat. Inertial recordings (accelerations, rotations) were concurrently recorded with a hip-worn IMU (sampling at 256 Hz). Jump height was evaluated based on flight time. The mean IMU-derived jump height was 27.1 (SD 3.8) cm, and the corresponding mean jump-mat-derived value was 21.5 (3.4) cm. While a significant 26% mean difference was observed between the methods (5.5 [95% limits of agreement 2.2 to 8.9] cm, P = 0.006), the correspondence between methods was excellent (ICC = 0.89). The difference between methods was weakly positively associated with jump height (r = 0.28, P = 0.007). Take-off velocity-derived jump height was also explored but produced only fair congruence. In conclusion, IMU-derived jump height exhibited excellent congruence to contact mat-based jump height and therefore presents a feasible alternative for jump height assessments in adolescents.

Nutrient intake among Samoan children aged 2-4 years in 2015.

BACKGROUND: Young children are particularly vulnerable to malnutrition as nutrition transition progresses. The aim of this study was to examine the adequacy of macro- and micronutrient intake among 2-4.99-year-old Samoan children. METHODS: Child dietary intake was measured using a 117-item food frequency questionnaire (FFQ) with a 30-day reference period. Daily total energy and nutrient intake was calculated by multiplying the frequency of daily consumption by the nutrient content of a fixed, standard portion size. Adequacy of macro- and micronutrient intake was determined using age-specific US Dietary Guidelines. RESULTS: Most children met or exceeded recommendations for carbohydrate, fat and protein intake. More than half of the sample were not meeting the Recommended Dietary Allowance (RDA) for calcium (59.0%), 44.6% were not meeting RDA for potassium and intake of vitamin A and E was inadequate among 25.9% and 25.6%, respectively. Eighty per cent of children exceeded the tolerable upper limit for sodium. Adequacy of intake varied by age and census region of residence. CONCLUSION: Since inadequate dietary micronutrient intake was more common among older children (4-4.99 years) and those in the rural region, intervention should be targeted at those groups.

Child, maternal and household-level correlates of nutritional status: a cross-sectional study among young Samoan children.

OBJECTIVE: Young children are particularly vulnerable to malnutrition as nutrition transition progresses. The present study aimed to document the prevalence, coexistence and correlates of nutritional status (stunting, overweight/obesity and anaemia) in Samoan children aged 24-59 months. DESIGN: A cross-sectional community-based survey. Height and weight were used to determine prevalence of stunting (height-for-age Z-score +2) based on WHO growth standards. Anaemia was determined using an AimStrip Hemoglobin test system (Hb <110 g/l). SETTING: Ten villages on the Samoan island of Upolu. SUBJECTS: Mother-child pairs (n 305) recruited using convenience sampling. RESULTS: Moderate or severe stunting was apparent in 20·3 % of children, 16·1 % were overweight/obese and 34·1 % were anaemic. Among the overweight/obese children, 28·6 % were also stunted and 42·9 % anaemic, indicating dual burden of malnutrition. Stunting was significantly less likely among girls (OR=0·41; 95 % CI 0·21, 0·79, P<0·01) than boys. Overweight/obesity was associated with higher family socio-economic status and decreased sugar intake (OR per 10 g/d=0·89, 95 % CI 0·80, 0·99, P=0·032). The odds of anaemia decreased with age and anaemia was more likely in children with an anaemic mother (OR=2·20; 95 % CI 1·22, 3·98, P=0·007). No child, maternal or household characteristic was associated with more than one of the nutritional status outcomes, highlighting the need for condition-specific interventions in this age group. CONCLUSIONS: The observed prevalences of stunting, overweight/obesity and anaemia suggest that it is critical to invest in nutrition and develop health programmes targeting early childhood growth and development in Samoa.

Influence of a School-based Physical Activity Intervention on Cortical Bone Mass Distribution: A 7-year Intervention Study.

Cortical bone mass and density varies across a bones length and cross section, and may be influenced by physical activity. This study evaluated the long-term effects of a pediatric school-based physical activity intervention on tibial cortical bone mass distribution. A total of 170 children (72 girls and 98 boys) from one school were provided with 200 min of physical education per week. Three other schools (44 girls and 47 boys) continued with the standard 60 min per week. Tibial total and cortical area, cortical density, polar stress-strain index (SSI), and the mass and density distribution around the center of mass (polar distribution, mg) and through the bones cortex (radial distribution subdivided into endo-, mid-, and pericortical volumetric BMD: mg/cm3) at three sites (14, 38, and 66 %) were assessed using peripheral quantitative computed tomography after 7 years. Girls in the intervention group had 2.5 % greater cortical thickness and 6.9 % greater SSI at the 66 % tibia, which was accompanied by significantly greater pericortical volumetric BMD compared to controls (all P < 0.05). Region-specific differences in cortical mass were also detected in the anterior, medial, and lateral sectors at the 38 and 66 % tibial sites. There were no group differences at the 14 % tibia site in girls, and no group differences in any of the bone parameters in boys. Additional school-based physical education over seven years was associated with greater tibial structure, strength, and region-specific adaptations in cortical bone mass and density distribution in girls, but not in boys.

Effects of Habitual Physical Activity and Fitness on Tibial Cortical Bone Mass, Structure and Mass Distribution in Pre-pubertal Boys and Girls: The Look Study.

Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P < 0.05), which was largely due to a 6.4-7.8 % (P < 0.05) greater cortical mass in the posterior-lateral, medial and posterior-medial 66 % tibial regions. Cortical area was not significantly different across PA-fitness categories in girls, but active-fit girls had 6.1 % (P < 0.05) greater SSIpolar compared to inactive-fit girls, which was likely due to their 6.7 % (P < 0.05) greater total bone area. There was also a small region-specific cortical mass benefit in the posterior-medial 66 % tibia cortex in active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.