Role of Physical Activity on Bone Mineral Content in Young Children

Previous studies identifying factors that influence peak bone mass have typically focused on older children, although it has been suggested that environmental factors early in life also may be important in optimizing the genetic potential for bone gain1 . Physical activity and calcium intake are considered major environmental factors influencing bone mass accretion. Longitudinal studies beginning in childhood show that high activity early in life is associated with high adult bone density2,3. The long-term effect between bone mass accretion and early calcium intake is less clear, with most trials finding that the beneficial bone effect of high calcium intake does not persist once the supplementation is withdrawn4 . Results of several studies related to bone changes and physical activity that we conducted in young children are reviewed belo

Muscle-bone Relationships in the Lower Leg of Healthy Pre-pubertal Females and Males

Muscle-bone relationships in healthy pre-pubertal children were investigated using four muscle measures as predictors of tibial strength: 66% tibia cross-sectional muscle area (CSMA) by pQCT; leg lean mass (LLM) by DXA; and muscle power (Power) and force (Force) measured during a two-footed jump. Polar strength strain index (pSSI), a calculated surrogate for bone strength at the 20% distal tibia, was obtained on 105 (54 male) self-assessed pre-pubertal children. The amount of muscle (CSMA, LLM) may influence bone strength more than muscle strength (Power, Force) during periods of rapid growth. Correlations and multiple regression partial-R values from models controlling for age, sex, height and weight were obtained for each muscle predictor. CSMA, LLM, Power and Force were positively correlated with pSSI (R=0.84, 0.92, 0.85; 0.66, respectively, all p\u3c 0.01). Partial-R values were highest for LLM (partial-R=0.21), similar for CSMA and Power (0.14, 0.15, respectively) and lowest for Force (0.04) in predicting pSSI. Muscle predictors were associated with total and cortical area (R=0.59 to 0.90; p\u3c 0.01 for all), but not cortical vBMD at the 20% distal tibia site. These data support relationships between muscle predictors and bone parameters measured by pQCT in healthy pre-pubertal children

Effect of Level of Farm Mechanization Early in Life on Bone Later in Life

OBJECTIVE: To determine whether an active rural lifestyle during childhood and adolescence, defined as low farm mechanization, was associated with bone measures later in life.METHODS: DXA bone data from total body, hip and spine, and pQCT data from 4% and 20% distal radius were obtained on 330 individuals (157 women) aged 20-66 years who farmed at least 75% of their lives. Primary bone outcomes included areal bone mineral density (aBMD), aBMD Z-scores, cortical and trabecular volumetric BMD, cortical thickness and periosteal circumference. Relationship between bone and recall of level of farm mechanization as a child was determined after stratifying by sex and controlling for covariates.RESULTS: Controlling for covariates, females from low mechanized farms had higher femoral neck (FN) bone area (p=0.03) than those on high or moderate mechanized farms. No group differences in pQCT ulna measurements or z-scores were found in either gender.CONCLUSION: A low farm mechanization level (high physical activity) prior to 20 years of age is associated with greater FN bone area in females. Future research that includes type and amount of physical activity performed will contribute to growing knowledge of how and when regular physical activity during childhood and adolescence affects adult bone health

Rates of Bone Loss in Young Adult Males

Osteoporosis-related fractures occur more frequently in women compared with men, but mortality is greater in men compared with women. Peak bone mass is a significant predictor of osteoporosis and fracture risk; therefore, it is important to optimize peak bone mass during young adulthood. Several recent longitudinal studies, which are summarized in this article, have investigated bone changes among young men. Cortical bone loss does not appear to be significant until individuals reach their mid-30s and is associated with decreased sex hormone concentrations. Significant trabecular bone loss in young men aged in their 20s has been reported and is associated with reduced lean mass and activity levels, especially among former athletes. Whether changes in activity levels among nonathletes lead to bone loss among young men requires further investigation

Community Outreach and Engagement to Prepare for Household Recruitment of National Children\u27s Study Participants in a Rural Setting

CONTEXT: The National Children\u27s Study (NCS) is a longitudinal study of environmental influences on children\u27s health. Recruitment of a representative birth cohort that will be followed until 21 years of age requires unique approaches across the nationwide study communities.PURPOSE: To describe community outreach and engagement in preparation for household recruitment of women of childbearing age at a rural-classified NCS location that includes 4 adjacent Northern Plains counties spanning 2,500 square miles.METHODS: Outreach and engagement methods focused on rural community characteristics. The team established an advisory council, conducted outreach meetings with agencies and groups, participated in local events, and collaborated with stakeholders. Study awareness was raised using radio announcements, local television stories, and widespread distribution of print materials through churches, businesses, and child care centers. Impact evaluation examined the number of stakeholder events by type. Outcome evaluation examined the number of households contacted for recruitment, numbers of age-eligible women who completed the screening, and exploration of whether women had heard about the study.FINDINGS: Over 300 outreach events occurred, ranging from tribal council meetings to parade entries. Recruitment outcomes were as follows: (1) 80% of 14,700 non-vacant households were reached for potential recruitment; (2) screening interviews were conducted with 89% of the 5,800 age-eligible women identified; and (3) 53% of women who completed the screening had heard about the studyCONCLUSIONS: Outreach targeted to rural communities facilitated strong recruitment outcomes. Collaboration with the cooperative extension service was a unique rural asset that facilitated relevant activities. Participant retention is an ongoing priority

Variation in Cortical Density Within the Cortical Shell of Individuals Across a Range in Densities and Ages

OBJECTIVES: The purpose of this study was to determine variability in cortical volumetric bone density (vBMD) from a single slice tibia image over a range of vBMD readings and ages. METHODS: Males and females (N=80; aged 6-80) were randomly selected from a previous study. Cortical vBMD at the anterior, posterior, medial, and lateral regions as well as the endocortical, mid-cortical, and pericortical regions of the cortical shell were determined using pQCT. RESULTS: Mean anterior ROI cortical vBMD (1111±11 mg/cm(3)) was lower than the posterior and lateral ROIs (1169±7 mg/cm(3) and 1151±9 mg/cm(3), respectively), (p CONCLUSIONS: Variability in cortical vBMD was higher among young individuals and those with lower overall cortical vBMD, while lowest in older individuals and men. The anterior ROI had lower mean cortical vBMD than posterior or lateral regions, and endocortical vBMD was lower than the mid- and pericortical regions

Experience Implementing a Public Health Surveillance System Designed for Fathers of Infants on a South Dakota American Indian Reservation

Introduction: Paternal behaviors and attitudes during pregnancy are not known. A health survey for fathers of recently born infants was developed to be administered concurrently with a maternal survey to assess parental behaviors and attitudes before, during and after pregnancy. Methods: Participants were parents of 149 American Indian infants born from April 1 and Dec. 31, 2015 who were recruited prospectively from data of all births in prespecified reservation counties representing Sisseton Wahpeton Oyate of the Lake Traverse Reservation. Data collection was via hard-copy or online survey. Results: Response rate among mothers was 62 percent (n=92). Of 149 births, 126 listed a father on the birth certificate and 51 percent (n=64) of these completed surveys on average 4.7 months post-birth. Healthwise, 90 percent of fathers reported being overweight or obese, but a small percent visited a health care worker in the previous year to be checked for diabetes (11 percent) or hypertension (14 percent). Among fathers who smoked in the last two years (73 percent), 77 percent of the mothers also smoked compared to 20 percent of mothers smoking if the father did not smoke (pConclusion: Conducting a health survey with both fathers and mothers in a reservation setting is feasible and the father’s attitudes and behaviors related to breastfeeding and smoking were associated with maternal health behaviors. Most fathers attended health care visits with the mother, but they were not being screened for health conditions despite a large proportion being overweight and smokers. Prenatal and antenatal visits may provide an opportune time to engage fathers and address paternal health issues

Cross-Sectional and Longitudinal Association between Glycemic Status and Body Composition in Men: A Population-Based Study

This study sought to evaluate the associations between changes in glycemic status and changes in total body (TB), trunk, and appendicular fat (FM) and lean mass (LM) in men. A population-based study of men aged 20–66 years at baseline were included in cross-sectional (n = 430) and three-year longitudinal (n = 411) analyses. Prediabetes was defined as fasting glucose 100–125 mg/dL. Type 2 diabetes (T2D) was determined by: self-reported diabetes, current anti-diabetic drug use (insulin/oral hypoglycemic agents), fasting glucose (≥126 mg/dL), or non-fasting glucose (≥200 mg/dL). Body composition was evaluated by dual-energy X-ray absorptiometry. Longitudinal analyses showed that changes in TB FM and LM, and appendicular LM differed among glycemic groups. Normoglycemic men who converted to prediabetes lost more TB and appendicular LM than men who remained normoglycemic (all, p \u3c 0.05). Normoglycemic or prediabetic men who developed T2D had a greater loss of TB and appendicular LM than men who remained normoglycemic (both, p \u3c 0.05). T2D men had greater gains in TB FM and greater losses in TB and appendicular LM than men who remained normoglycemic (all, p \u3c 0.05). Dysglycemia is associated with adverse changes in TB and appendicular LM

Fat Mass Gain is Lower in Calcium-supplemented than in Unsupplemented Preschool Children with Low Dietary Calcium Intakes

BACKGROUND: Dietary calcium may play a role in the stimulation of lipolysis and the inhibition of lipogenesis, thereby reducing body fat.OBJECTIVE: The aim was to determine whether an association existed between change in percentage body fat (%BF) or fat mass and calcium intake in children aged 3-5 y.DESIGN: A secondary analysis of a 1-y randomized calcium and activity trial in 178 children was conducted. Three-day diet records and 48-h accelerometer readings were obtained at 0, 6, and 12 mo. Body composition was measured by dual-energy X-ray absorptiometry at 0 and 12 mo.RESULTS: The decrease in %BF was less in girls (-0.6 +/- 2.8%) than in boys (-1.5 +/- 2.6%; P = 0.03) and correlated with age (r = 0.19, P = 0.01) and maternal body mass index (r = 0.19, P = 0.02). Changes in fat mass were not significantly different by activity group or between children randomly assigned to receive calcium or placebo (0.5 +/- 0.9 and 0.6 +/- 0.8 kg, respectively; P = 0.32). Similar findings were observed for the change in %BF. No correlations between %BF and fat mass changes and dietary calcium (r = -0.01, P = 0.9 and r = -0.05, P = 0.5) or total (dietary + supplement) calcium intake (r = -0.02, P = 0.8 and r = -0.06, P = 0.4) were observed. Among children in the lowest tertile of dietary calcium (/d), fat mass gain was lower in the calcium group (0.3 +/- 0.5 kg) than in the placebo group (0.8 +/- 1.1 kg) (P = 0.04) but was not correlated with mean total calcium intake (r = -0.20).CONCLUSION: These findings support a weak relation between changes in fat mass gain and calcium intake in preschool children, who typically consume below recommended amounts of dietary calcium

South Dakota Pregnancy Survey 2016 Data Report

The South Dakota Department of Health, in conjunction with the EA Martin Program at South Dakota State University, conducted a 2016 Pregnancy Risk Assessment Monitoring System (PRAMS)-like surveillance project. The 2016 South Dakota PRAMS-like survey was a statewide population-based survey based on a stratified random sample of women who gave birth to a live-born infant, thereby allowing rates to be estimated for South Dakota mothers giving birth in 2016. The topics included in this survey were selected to enhance our understanding of maternal attitudes and behaviors around the time of pregnancy and the weighted response rate was 67.6%