Limiting Television to Reduce Childhood Obesity: Cost-Effectiveness of Five Population Strategies

Objective: To quantify the potential population-wide costs, number of individuals reached, and impact on obesity of five effective interventions to reduce children's television viewing if implemented nationally. Study Design: Utilizing evidence from systematic reviews, the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES) microsimulation model estimated the cost, population reach, and impact on childhood obesity from 2020 to 2030 of five hypothetical policy strategies to reduce the negative impact of children's TV exposure: (1) eliminating the tax deductibility of food and beverage advertising; (2) targeting TV reduction during home visiting programs; (3) motivational interviewing to reduce home television time at Women, Infants, and Children (WIC) clinic visits; (4) adoption of a television-reduction curriculum in child care; and (5) limiting noneducational television in licensed child care settings. Results: Eliminating the tax deductibility of food advertising could reach the most children [106 million, 95% uncertainty interval (UI): 105-107 million], prevent the most cases of obesity (78,700, 95% UI: 30,200-130,000), and save more in health care costs than it costs to implement. Strategies targeting young children in child care and WIC also cost little to implement (between $0.19 and $32.73 per child reached), and, although reaching fewer children because of the restricted age range, were estimated to prevent between 25,500 (95% UI: 4600-59,300) and 35,400 (95% UI: 13,200-62,100) cases of obesity. Home visiting to reduce television viewing had high costs and a low reach. Conclusions: Interventions to reduce television exposure across a range of settings, if implemented widely, could help prevent childhood obesity in the population at relatively low cost.

Projected U.S. State-Level Prevalence of Adult Obesity and Severe Obesity

BACKGROUND

Although the national obesity epidemic has been well documented, less is known about obesity at the U.S. state level. Current estimates are based on body measures reported by persons themselves that underestimate the prevalence of obesity, especially severe obesity.

METHODS

We developed methods to correct for self-reporting bias and to estimate state-specific and demographic subgroup-specific trends and projections of the prevalence of categories of body-mass index (BMI). BMI data reported by 6,264,226 adults (18 years of age or older) who participated in the Behavioral Risk Factor Surveillance System Survey (1993-1994 and 1999-2016) were obtained and corrected for quantile-specific self-reporting bias with the use of measured data from 57,131 adults who participated in the National Health and Nutrition Examination Survey. We fitted multinomial regressions for each state and subgroup to estimate the prevalence of four BMI categories from 1990 through 2030: underweight or normal weight (BMI [the weight in kilograms divided by the square of the height in meters], <25), overweight (25 to <30), moderate obesity (30 to <35), and severe obesity (≥35). We evaluated the accuracy of our approach using data from 1990 through 2010 to predict 2016 outcomes.

RESULTS

The findings from our approach suggest with high predictive accuracy that by 2030 nearly 1 in 2 adults will have obesity (48.9%; 95% confidence interval [CI], 47.7 to 50.1), and the prevalence will be higher than 50% in 29 states and not below 35% in any state. Nearly 1 in 4 adults is projected to have severe obesity by 2030 (24.2%; 95% CI, 22.9 to 25.5), and the prevalence will be higher than 25% in 25 states. We predict that, nationally, severe obesity is likely to become the most common BMI category among women (27.6%; 95% CI, 26.1 to 29.2), non-Hispanic black adults (31.7%; 95% CI, 29.9 to 33.4), and low-income adults (31.7%; 95% CI, 30.2 to 33.2).

CONCLUSIONS

Our analysis indicates that the prevalence of adult obesity and severe obesity will continue to increase nationwide, with large disparities across states and demographic subgroups. (Funded by the JPB Foundation.).

Cost-Effectiveness of Water Promotion Strategies in Schools for Preventing Childhood Obesity and Increasing Water Intake

OBJECTIVE

This study aimed to estimate the cost-effectiveness and impact on childhood obesity of installation of chilled water dispensers ("water jets") on school lunch lines and to compare water jets' cost, reach, and impact on water consumption with three additional strategies.

METHODS

The Childhood Obesity Intervention Cost Effectiveness Study(CHOICES) microsimulation model estimated the cost-effectiveness of water jets on US childhood obesity cases prevented in 2025. Also estimated were the cost, number of children reached, and impact on water consumption of the installation of water jets and three other strategies.

RESULTS

Installing water jets on school lunch lines was projected to reach 29.6 million children (95% uncertainty interval [UI]: 29.4 million-29.8 million), cost $4.25 (95% UI: $2.74-$5.69) per child, prevent 179,550 cases of childhood obesity in 2025 (95% UI: 101,970-257,870), and save $0.31 in health care costs per dollar invested (95% UI: $0.15-$0.55). In the secondary analysis, installing cup dispensers next to existing water fountains was the least costly but also had the lowest population reach.

CONCLUSIONS

Installating water jet dispensers on school lunch lines could also save almost half of the dollars needed for implementation via a reduction in obesity-related health care costs. School-based interventions to promote drinking water may be relatively inexpensive strategies for improving child health.

Assessing the effectiveness of training models for national scale-up of an evidence-based nutrition and physical activity intervention: a group randomized trial

BACKGROUND

There is a great need to identify implementation strategies to successfully scale-up public health interventions in order to achieve their intended population impact. The Out-of-school Nutrition and Physical Activity group-randomized trial previously demonstrated improvements in children's vigorous physical activity and the healthfulness of foods and beverages consumed. This implementation study aimed to assess the effects and costs of two training models to scale-up this evidence-based intervention.

METHODS

A 3-arm group-randomized trial was conducted to compare effectiveness of in-person and online training models for scaling up the intervention compared to controls. One-third of sites were randomized to the in-person train-the-trainer model: local YMCA facilitators attended a training session and then conducted three learning collaborative meetings and technical assistance. One-third were assigned to the online model, consisting of self-paced monthly learning modules, videos, quizzes, and facilitated discussion boards. Remaining sites served as controls. Fifty-three afterschool sites from three YMCA Associations in different regions of the country completed baseline and follow-up observations using a validated tool of afterschool nutrition and physical activity practices. We used multivariable regression models, accounting for clustering of observations, to assess intervention effects on an aggregate afterschool practice primary outcome, and conducted secondary analyses of nine intervention goals (e.g. serving water). Cost data were collected to determine the resources to implement each training model.

RESULTS

Changes in the primary outcome indicate that, on average, sites in the in-person arm achieved 0.44 additional goals compared to controls (95%CI 0.02, 0.86, p = 0.04). Increases in the number of additional goals achieved in sites in the online arm were not significantly greater than control sites (+ 0.28, 95% CI -0.18, 0.73, p = 0.24). Goal-specific improvements were observed for increasing water offered in the in-person arm and fruits and vegetables offered in the online arm. The cost per person trained was $678 for the in-person training model and $336 for the on-line training model.

CONCLUSIONS

This pilot trial presents promising findings on implementation strategies for scale-up. It validated the in-person training model as an effective approach. The less expensive online training may be a useful option for geographically disbursed sites where in-person training is challenging.

TRIAL REGISTRATION

Although this study does not report the results of a health care intervention on human subjects, it is a randomized trial and was therefore retrospectively registered in ClinicalTrials.gov on July 4, 2019 in accordance with the BMC guidelines to ensure the complete publication of all results (NCT04009304).

Cost-Effectiveness Analysis and Stakeholder Evaluation of 2 Obesity Prevention Policies in Maine, US

OBJECTIVE

To evaluate the potential cost-effectiveness of and stakeholder perspectives on a sugar-sweetened beverage (SSB) excise tax and a Supplemental Nutrition Assistance Program (SNAP) policy that would not allow SSB purchases in Maine, US.

DESIGN

A cost-effectiveness simulation model combined with stakeholder interviews.

SETTING

Maine, US.

PARTICIPANTS

Microsimulation of the Maine population in 2015 and interviews with stakeholders (n = 14). Study conducted from 2013 to 2017.

MAIN OUTCOME MEASURES

Health care cost savings, net costs, and quality-adjusted life-years (QALYs) from 2017 to 2027. Stakeholder positions on policies. Retail SSB cost and implementation cost data were collected.

ANALYSIS

Childhood Obesity Intervention Cost-Effectiveness Study project microsimulation model with uncertainty analysis to estimate cost-effectiveness. Thematic stakeholder interview coding.

RESULTS

Over 10 years, the SSB and SNAP policies were projected to reduce health care costs by $78.3 million (95% uncertainty interval [UI], $31.7 million-$185 million) and $15.3 million (95% UI, $8.32 million-$23.9 million), respectively. The SSB and SNAP policies were projected to save 3,560 QALYs (95% UI, 1,447-8,361) and 749 QALYs (95% UI, 415-1,168), respectively. Stakeholders were more supportive of SSB taxes than the SNAP policy because of equity concerns associated with the SNAP policy.

CONCLUSIONS AND IMPLICATIONS

Cost-effectiveness analysis provided evidence of potential health improvement and cost savings to state-level stakeholders weighing broader implementation considerations.

Effects of a before-school program on student physical activity levels

Many children are not sufficiently physically active. This study uses a quasi-experimental design to evaluate whether participation in a before-school physical activity program called Build Our Kids' Success (BOKS) increases physical activity. Participants (n = 426) were students in Fall, 2016 enrolled in BOKS programming and matched non-BOKS control students from the same grades (Kindergarten-6) and schools in Massachusetts and Rhode Island. Analyses conducted in 2017 examined differences between children in BOKS versus controls in total daily steps, minutes of moderate-to-vigorous (MVPA), vigorous (VPA), and total physical activity (TPA) assessed via Fitbit Charge HR™ monitors. Additional analyses compared physical activity on program days and non-program days. Students (mean age = 8.6 y; 47% female, 58% White, Non-Hispanic) wore monitors an average of 21.7 h/day on 3.2 days during the school week. Compared with controls, on BOKS days, BOKS participants accumulated more steps (1147, 95% confidence interval (CI): 583-1712, P < 0.001), MVPA minutes (13.4, 95% CI: 6.6-20.3, P < 0.001), and VPA minutes (4.0, 95% CI: 1.2-6.7, P = 0.005). Across all school days, BOKS participants accumulated more total steps than controls (716, 95% CI: 228-1204, P = 0.004). Compared to days without BOKS programming, on BOKS days, BOKS participants accumulated more steps (1153; 95% CI: 841-1464, P < 0.001) and daily minutes of MVPA (8.8, 95% CI: 5.3-12.2, P < 0.001), VPA (3.0, 95% CI: 1.6-4.5, P < 0.001), and TPA (20.8, 95% CI: 13.6-28.1, P < 0.001). BOKS programming promotes engagement in additional accumulated steps during the school week and physical activity on days that students participate. Clinical Trial Registration: www.ClinicalTrials.gov, NCT03403816, available at: https://clinicaltrials.gov/ct2/show/NCT03403816?term=NCT03403816&rank=1.

Simulation of Growth Trajectories of Childhood Obesity into Adulthood

BACKGROUND

Although the current obesity epidemic has been well documented in children and adults, less is known about long-term risks of adult obesity for a given child at his or her present age and weight. We developed a simulation model to estimate the risk of adult obesity at the age of 35 years for the current population of children in the United States.

METHODS

We pooled height and weight data from five nationally representative longitudinal studies totaling 176,720 observations from 41,567 children and adults. We simulated growth trajectories across the life course and adjusted for secular trends. We created 1000 virtual populations of 1 million children through the age of 19 years that were representative of the 2016 population of the United States and projected their trajectories in height and weight up to the age of 35 years. Severe obesity was defined as a body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) of 35 or higher in adults and 120% or more of the 95th percentile in children.

RESULTS

Given the current level of childhood obesity, the models predicted that a majority of today's children (57.3%; 95% uncertainly interval [UI], 55.2 to 60.0) will be obese at the age of 35 years, and roughly half of the projected prevalence will occur during childhood. Our simulations indicated that the relative risk of adult obesity increased with age and BMI, from 1.17 (95% UI, 1.09 to 1.29) for overweight 2-year-olds to 3.10 (95% UI, 2.43 to 3.65) for 19-year-olds with severe obesity. For children with severe obesity, the chance they will no longer be obese at the age of 35 years fell from 21.0% (95% UI, 7.3 to 47.3) at the age of 2 years to 6.1% (95% UI, 2.1 to 9.9) at the age of 19 years.

CONCLUSIONS

On the basis of our simulation models, childhood obesity and overweight will continue to be a major health problem in the United States. Early development of obesity predicted obesity in adulthood, especially for children who were severely obese. (Funded by the JPB Foundation and others.).

Cost-Effectiveness of a Clinical Childhood Obesity Intervention

OBJECTIVES

To estimate the cost-effectiveness and population impact of the national implementation of the Study of Technology to Accelerate Research (STAR) intervention for childhood obesity.

METHODS

In the STAR cluster-randomized trial, 6- to 12-year-old children with obesity seen at pediatric practices with electronic health record (EHR)-based decision support for primary care providers and self-guided behavior-change support for parents had significantly smaller increases in BMI than children who received usual care. We used a microsimulation model of a national implementation of STAR from 2015 to 2025 among all pediatric primary care providers in the United States with fully functional EHRs to estimate cost, impact on obesity prevalence, and cost-effectiveness.

RESULTS

The expected population reach of a 10-year national implementation is ∼2 million children, with intervention costs of $119 per child and $237 per BMI unit reduced. At 10 years, assuming maintenance of effect, the intervention is expected to avert 43 000 cases and 226 000 life-years with obesity at a net cost of $4085 per case and $774 per life-year with obesity averted. Limiting implementation to large practices and using higher estimates of EHR adoption improved both cost-effectiveness and reach, whereas decreasing the maintenance of the intervention's effect worsened the former.

CONCLUSIONS

A childhood obesity intervention with electronic decision support for clinicians and self-guided behavior-change support for parents may be more cost-effective than previous clinical interventions. Effective and efficient interventions that target children with obesity are necessary and could work in synergy with population-level prevention strategies to accelerate progress in reducing obesity prevalence.

Using cost-effectiveness analysis to prioritize policy and programmatic approaches to physical activity promotion and obesity prevention in childhood

Participation in recommended levels of physical activity promotes a healthy body weight and reduced chronic disease risk. To inform investment in prevention initiatives, we simulate the national implementation, impact on physical activity and childhood obesity and associated cost-effectiveness (versus the status quo) of six recommended strategies that can be applied throughout childhood to increase physical activity in US school, afterschool and childcare settings. In 2016, the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES) systematic review process identified six interventions for study. A microsimulation model estimated intervention outcomes 2015-2025 including changes in mean MET-hours/day, intervention reach and cost per person, cost per MET-hour change, ten-year net costs to society and cases of childhood obesity prevented. First year reach of the interventions ranged from 90,000 youth attending a Healthy Afterschool Program to 31.3 million youth reached by Active School Day policies. Mean MET-hour/day/person increases ranged from 0.05 MET-hour/day/person for Active PE and Healthy Afterschool to 1.29 MET-hour/day/person for the implementation of New Afterschool Programs. Cost per MET-hour change ranged from cost saving to $3.14. Approximately 2500 to 110,000 cases of children with obesity could be prevented depending on the intervention implemented. All of the six interventions are estimated to increase physical activity levels among children and adolescents in the US population and prevent cases of childhood obesity. Results do not include other impacts of increased physical activity, including cognitive and behavioral effects. Decision-makers can use these methods to inform prioritization of physical activity promotion and obesity prevention on policy agendas.

Three Interventions That Reduce Childhood Obesity Are Projected To Save More Than They Cost To Implement

Policy makers seeking to reduce childhood obesity must prioritize investment in treatment and primary prevention. We estimated the cost-effectiveness of seven interventions high on the obesity policy agenda: a sugar-sweetened beverage excise tax; elimination of the tax subsidy for advertising unhealthy food to children; restaurant menu calorie labeling; nutrition standards for school meals; nutrition standards for all other food and beverages sold in schools; improved early care and education; and increased access to adolescent bariatric surgery. We used systematic reviews and a microsimulation model of national implementation of the interventions over the period 2015-25 to estimate their impact on obesity prevalence and their cost-effectiveness for reducing the body mass index of individuals. In our model, three of the seven interventions--excise tax, elimination of the tax deduction, and nutrition standards for food and beverages sold in schools outside of meals--saved more in health care costs than they cost to implement. Each of the three interventions prevented 129,000-576,000 cases of childhood obesity in 2025. Adolescent bariatric surgery had a negligible impact on obesity prevalence. Our results highlight the importance of primary prevention for policy makers aiming to reduce childhood obesity.

US States' Childhood Obesity Surveillance Practices and Recommendations for Improving Them, 2014-2015

Introduction

Routine collection, analysis, and reporting of data on child height, weight, and body mass index (BMI), particularly at the state and local levels, are needed to monitor the childhood obesity epidemic, plan intervention strategies, and evaluate the impact of interventions. Child BMI surveillance systems operated by the US government do not provide state or local data on children across a range of ages. The objective of this study was to describe the extent to which state governments conduct child BMI surveillance.

Methods

From August through December 2014, we conducted a structured telephone survey with state government administrators to learn about state surveillance of child BMI. We also searched websites of state health and education agencies for information about state surveillance.

Results

State agency administrators in 48 states and Washington, DC, completed telephone interviews (96% response rate). Based on our interviews and Internet research, we determined that 14 states collect child BMI data in a manner consistent with standard definitions of public health surveillance.

Conclusion

The absence of child BMI surveillance systems in most states limits the ability of public health practitioners and policymakers to develop and evaluate responses to the childhood obesity epidemic. Greater investment in surveillance is needed to identify the most effective and cost-effective childhood obesity interventions.

State-level estimates of childhood obesity prevalence in the United States corrected for report bias

BACKGROUND/OBJECTIVES

State-specific obesity prevalence data are critical to public health efforts to address the childhood obesity epidemic. However, few states administer objectively measured body mass index (BMI) surveillance programs. This study reports state-specific childhood obesity prevalence by age and sex correcting for parent-reported child height and weight bias.

SUBJECTS/METHODS

As part of the Childhood Obesity Intervention Cost Effectiveness Study (CHOICES), we developed childhood obesity prevalence estimates for states for the period 2005-2010 using data from the 2010 US Census and American Community Survey (ACS), 2003-2004 and 2007-2008 National Survey of Children's Health (NSCH) (n=133 213), and 2005-2010 National Health and Nutrition Examination Surveys (NHANES) (n=9377; ages 2-17). Measured height and weight data from NHANES were used to correct parent-report bias in NSCH using a non-parametric statistical matching algorithm. Model estimates were validated against surveillance data from five states (AR, FL, MA, PA and TN) that conduct censuses of children across a range of grades.

RESULTS

Parent-reported height and weight resulted in the largest overestimation of childhood obesity in males ages 2-5 years (NSCH: 42.36% vs NHANES: 11.44%). The CHOICES model estimates for this group (12.81%) and for all age and sex categories were not statistically different from NHANES. Our modeled obesity prevalence aligned closely with measured data from five validation states, with a 0.64 percentage point mean difference (range: 0.23-1.39) and a high correlation coefficient (r=0.96, P=0.009). Estimated state-specific childhood obesity prevalence ranged from 11.0 to 20.4%.

CONCLUSION

Uncorrected estimates of childhood obesity prevalence from NSCH vary widely from measured national data, from a 278% overestimate among males aged 2-5 years to a 44% underestimate among females aged 14-17 years. This study demonstrates the validity of the CHOICES matching methods to correct the bias of parent-reported BMI data and highlights the need for public release of more recent data from the 2011 to 2012 NSCH.

Promoting Physical Activity With the Out of School Nutrition and Physical Activity (OSNAP) Initiative: A Cluster-Randomized Controlled Trial

IMPORTANCE

Millions of children attend after-school programs in the United States. Increasing physical activity levels of program participants could have a broad effect on children's health.

OBJECTIVE

To test the effectiveness of the Out of School Nutrition and Physical Activity (OSNAP) Initiative in increasing children's physical activity levels in existing after-school programs.

DESIGN, SETTING, AND PARTICIPANTS

Cluster-randomized controlled trial with matched program pairs. Baseline data were collected September 27 through November 12, 2010, with follow-up data collected April 25 through May 27, 2011. The dates of our analysis were March 11, 2014, through August 18, 2015. The setting was 20 after-school programs in Boston, Massachusetts. All children 5 to 12 years old in participating programs were eligible for study inclusion.

INTERVENTIONS

Ten programs participated in a series of three 3-hour learning collaborative workshops, with additional optional opportunities for training and technical assistance.

MAIN OUTCOMES AND MEASURES

Change in number of minutes and bouts of moderate to vigorous physical activity, vigorous physical activity, and sedentary activity and change in total accelerometer counts between baseline and follow-up.

RESULTS

Participants with complete data were 402 racially/ethnically diverse children, with a mean age of 7.7 years. Change in the duration of physical activity opportunities offered to children during program time did not differ between conditions (-1.2 minutes; 95% CI, -14.2 to 12.4 minutes; P = .87). Change in moderate to vigorous physical activity minutes accumulated by children during program time did not differ significantly by intervention status (-1.0; 95% CI, -3.3 to 1.3; P = .40). Total minutes per day of vigorous physical activity (3.2; 95% CI, 1.8-4.7; P < .001), vigorous physical activity minutes in bouts (4.1; 95% CI, 2.7-5.6; P < .001), and total accelerometer counts per day (16,894; 95% CI, 5101-28,686; P = .01) increased significantly during program time among intervention participants compared with control participants.

CONCLUSIONS AND RELEVANCE

Although programs participating in the OSNAP Initiative did not allot significantly more time for physical activity, they successfully made existing time more vigorously active for children receiving the intervention.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01396473.

Modeling the Cost Effectiveness of Child Care Policy Changes in the U.S

INTRODUCTION

Child care facilities influence diet and physical activity, making them ideal obesity prevention settings. The purpose of this study is to quantify the health and economic impacts of a multi-component regulatory obesity policy intervention in licensed U.S. child care facilities.

METHODS

Two-year costs and BMI changes resulting from changes in beverage, physical activity, and screen time regulations affecting a cohort of up to 6.5 million preschool-aged children attending child care facilities were estimated in 2014 using published data. A Markov cohort model simulated the intervention's impact on changes in the U.S. population from 2015 to 2025, including short-term BMI effects and 10-year healthcare expenditures. Future outcomes were discounted at 3% annually. Probabilistic sensitivity analyses simulated 95% uncertainty intervals (UIs) around outcomes.

RESULTS

Regulatory changes would lead children to watch less TV, get more minutes of moderate and vigorous physical activity, and consume fewer sugar-sweetened beverages. Within the 6.5 million eligible population, national implementation could reach 3.69 million children, cost $4.82 million in the first year, and result in 0.0186 fewer BMI units (95% UI=0.00592 kg/m(2), 0.0434 kg/m(2)) per eligible child at a cost of $57.80 per BMI unit avoided. Over 10 years, these effects would result in net healthcare cost savings of $51.6 (95% UI=$14.2, $134) million. The intervention is 94.7% likely to be cost saving by 2025.

CONCLUSIONS

Changing child care regulations could have a small but meaningful impact on short-term BMI at low cost. If effects are maintained for 10 years, obesity-related healthcare cost savings are likely.

Cost Effectiveness of Childhood Obesity Interventions: Evidence and Methods for CHOICES

INTRODUCTION

The childhood obesity epidemic continues in the U.S., and fiscal crises are leading policymakers to ask not only whether an intervention works but also whether it offers value for money. However, cost-effectiveness analyses have been limited. This paper discusses methods and outcomes of four childhood obesity interventions: (1) sugar-sweetened beverage excise tax (SSB); (2) eliminating tax subsidy of TV advertising to children (TV AD); (3) early care and education policy change (ECE); and (4) active physical education (Active PE).

METHODS

Cost-effectiveness models of nationwide implementation of interventions were estimated for a simulated cohort representative of the 2015 U.S. population over 10 years (2015-2025). A societal perspective was used; future outcomes were discounted at 3%. Data were analyzed in 2014. Effectiveness, implementation, and equity issues were reviewed.

RESULTS

Population reach varied widely, and cost per BMI change ranged from $1.16 (TV AD) to $401 (Active PE). At 10 years, assuming maintenance of the intervention effect, three interventions would save net costs, with SSB and TV AD saving $55 and $38 for every dollar spent. The SSB intervention would avert disability-adjusted life years, and both SSB and TV AD would increase quality-adjusted life years. Both SSB ($12.5 billion) and TV AD ($80 million) would produce yearly tax revenue.

CONCLUSIONS

The cost effectiveness of these preventive interventions is greater than that seen for published clinical interventions to treat obesity. Cost-effectiveness evaluations of childhood obesity interventions can provide decision makers with information demonstrating best value for the money.

Validity and reliability of a simple, low-cost measure to quantify children's dietary intake in afterschool settings

BACKGROUND

Interest in evaluating and improving children's diets in afterschool settings has grown, necessitating the development of feasible yet valid measures for capturing children's intake in such settings.

OBJECTIVE

The purpose of this study was to test the criterion validity and cost of three unobtrusive visual estimation methods compared with a plate-weighing method: direct onsite observation using a 4-category rating scale and offsite rating of digital photographs taken onsite using 4- and 10-category scales.

DESIGN

Researchers observed and photographed 174 total snack meals consumed across 2 days at each program.

PARTICIPANTS/SETTING

Participants were 111 children in first through sixth grades attending four afterschool programs in Boston, MA, during December 2011.

STATISTICAL ANALYSIS

Visual estimates of consumption were compared to weighed estimates (the criterion measure) using intraclass correlations.

RESULTS

All three methods were highly correlated with the criterion measure, ranging from 0.92 to 0.94 for total calories consumed, 0.86 to 0.94 for consumption of prepackaged beverages, 0.90 to 0.93 for consumption of fruits/vegetables, and 0.92 to 0.96 for consumption of grains. For water, which was not preportioned, coefficients ranged from 0.47 to 0.52. The photographic methods also demonstrated excellent interrater reliability: 0.84 to 0.92 for the 4-point and 0.92 to 0.95 for the 10-point scale. The costs of the methods for estimating intake ranged from $0.62 per observation for the onsite direct visual method to $0.95 per observation for the criterion measure.

CONCLUSIONS

Feasible, inexpensive methods can validly and reliably measure children's dietary intake in afterschool settings. Improving precision in measures of children's dietary intake can reduce the likelihood of spurious or null findings in future studies.

Validity of a practitioner-administered observational tool to measure physical activity, nutrition, and screen time in school-age programs

BACKGROUND

Nutrition and physical activity interventions have been effective in creating environmental changes in afterschool programs. However, accurate assessment can be time-consuming and expensive as initiatives are scaled up for optimal population impact. This study aims to determine the criterion validity of a simple, low-cost, practitioner-administered observational measure of afterschool physical activity, nutrition, and screen time practices and child behaviors.

METHODS

Directors from 35 programs in three cities completed the Out-of-School Nutrition and Physical Activity Observational Practice Assessment Tool (OSNAP-OPAT) on five days. Trained observers recorded snacks served and obtained accelerometer data each day during the same week. Observations of physical activity participation and snack consumption were conducted on two days. Correlations were calculated to validate weekly average estimates from OSNAP-OPAT compared to criterion measures. Weekly criterion averages are based on 175 meals served, snack consumption of 528 children, and physical activity levels of 356 children.

RESULTS

OSNAP-OPAT validly assessed serving water (r = 0.73), fruits and vegetables (r = 0.84), juice >4oz (r = 0.56), and grains (r = 0.60) at snack; sugary drinks (r = 0.70) and foods (r = 0.68) from outside the program; and children's water consumption (r = 0.56) (all p <0.05). Reports of physical activity time offered were correlated with accelerometer estimates (minutes of moderate and vigorous physical activity r = 0.59, p = 0.02; vigorous physical activity r = 0.63, p = 0.01). The reported proportion of children participating in moderate and vigorous physical activity was correlated with observations (r = 0.48, p = 0.03), as were reports of computer (r = 0.85) and TV/movie (r = 0.68) time compared to direct observations (both p < 0.01).

CONCLUSIONS

OSNAP-OPAT can assist researchers and practitioners in validly assessing nutrition and physical activity environments and behaviors in afterschool settings.

TRIAL REGISTRATION

Phase 1 of this measure validation was conducted during a study registered at clinicaltrials.gov NCT01396473.

Identifying sources of children's consumption of junk food in Boston after-school programs, April-May 2011

INTRODUCTION

Little is known about how the nutrition environment in after-school settings may affect children's dietary intake. We measured the nutritional quality of after-school snacks provided by programs participating in the National School Lunch Program or the Child and Adult Care Food Program and compared them with snacks brought from home or purchased elsewhere (nonprogram snacks). We quantified the effect of nonprogram snacks on the dietary intake of children who also received program-provided snacks during after-school time. Our study objective was to determine how different sources of snacks affect children's snack consumption in after-school settings.

METHODS

We recorded snacks served to and brought in by 298 children in 18 after-school programs in Boston, Massachusetts, on 5 program days in April and May 2011. We measured children's snack consumption on 2 program days using a validated observation protocol. We then calculated within-child change-in-change models to estimate the effect of nonprogram snacks on children's dietary intake after school.

RESULTS

Nonprogram snacks contained more sugary beverages and candy than program-provided snacks. Having a nonprogram snack was associated with significantly higher consumption of total calories (+114.7 kcal, P < .001), sugar-sweetened beverages (+0.5 oz, P = .01), desserts (+0.3 servings, P < .001), and foods with added sugars (+0.5 servings; P < .001) during the snack period.

CONCLUSION

On days when children brought their own after-school snack, they consumed more salty and sugary foods and nearly twice as many calories than on days when they consumed only program-provided snacks. Policy strategies limiting nonprogram snacks or setting nutritional standards for them in after-school settings should be explored further as a way to promote child health.

Improving nutrition and physical activity policies in afterschool programs: results from a group-randomized controlled trial

OBJECTIVE

Afterschool programs can be health-promoting environments for children. Written policies positively influence nutrition and physical activity (PA) environments, but effective strategies for building staff capacity to write such policies have not been evaluated. This study measures the comprehensiveness of written nutrition, PA, and screen time policies in afterschool programs and assesses impact of the Out of School Nutrition and Physical Activity (OSNAP) intervention on key policies.

METHODS

Twenty afterschool programs in Boston, MA participated in a group-randomized, controlled trial from September 2010 to June 2011. Intervention program staff attended learning collaboratives focused on practice and policy change. The Out-of-School Time (OST) Policy Assessment Index evaluated written policies. Inter-rater reliability and construct validity of the measure and impact of the intervention on written policies were assessed.

RESULTS

The measure demonstrated moderate to excellent inter-rater reliability (Spearman's r=0.53 to 0.97) and construct validity. OSNAP was associated with significant increases in standards-based policy statements surrounding snacks (+2.6, p=0.003), beverages (+2.3, p=0.008), screen time (+0.8, p=0.046), family communication (+2.2, p=0.002), and a summary index of OSNAP goals (+3.3, p=0.02).

CONCLUSIONS

OSNAP demonstrated success in building staff capacity to write health-promoting policy statements. Future research should focus on determining policy change impact on practices.

Increasing water availability during afterschool snack: evidence, strategies, and partnerships from a group randomized trial

BACKGROUND

Providing drinking water to U.S. children during school meals is a recommended health promotion strategy and part of national nutrition policy. Urban school systems have struggled with providing drinking water to children, and little is known about how to ensure that water is served, particularly in afterschool settings.

PURPOSE

To assess the effectiveness of an intervention designed to promote water as the beverage of choice in afterschool programs.

DESIGN

The Out of School Nutrition and Physical Activity Initiative (OSNAP) used a community-based collaboration and low-cost strategies to provide water after school. A group RCT was used to evaluate the intervention. Data were collected in 2010-2011 and analyzed in 2011.

SETTING/PARTICIPANTS

Twenty afterschool programs in Boston were randomized to intervention or control (delayed intervention).

INTERVENTION

Intervention sites participated in learning collaboratives focused on policy and environmental changes to increase healthy eating, drinking, and physical activity opportunities during afterschool time (materials available at www.osnap.org). Collaboration between Boston Public Schools Food and Nutrition Services, afterschool staff, and researchers established water-delivery systems to ensure children were served water during snack time.

MAIN OUTCOME MEASURES

Average ounces of water served to children per day was recorded by direct observation at each program at baseline and 6-month follow-up over 5 consecutive school days. Secondary measures directly observed included ounces of other beverages served, other snack components, and water-delivery system.

RESULTS

Participation in the intervention was associated with an increased average volume of water served (+3.6 ounces/day; p=0.01) during snack. On average, the intervention led to a daily decrease of 60.9 kcals from beverages served during snack (p=0.03).

CONCLUSIONS

This study indicates the OSNAP intervention, including strategies to overcome structural barriers and collaboration with key actors, can increase offerings of water during afterschool snack. OSNAP appears to be an effective strategy to provide water in afterschool settings that can be helpful in implementing new U.S. Department of Agriculture guidelines regarding water availability during lunch and afterschool snack.

Rationale, design and methods of the HEALTHY study behavior intervention component

HEALTHY was a multi-center primary prevention trial designed to reduce risk factors for type 2 diabetes in adolescents. Seven centers each recruited six middle schools that were randomized to either intervention or control. The HEALTHY intervention integrated multiple components in nutrition, physical education, behavior change and communications and promotion. The conceptual rationale as well as the design and development of the behavior intervention component are described. Pilot study data informed the development of the behavior intervention component. Principles of social learning and health-related behavior change were incorporated. One element of the behavior intervention component was a sequence of peer-led, teacher-facilitated learning activities known as FLASH (Fun Learning Activities for Student Health). Five FLASH modules were implemented over five semesters of the HEALTHY study, with the first module delivered in the second semester of the sixth grade and the last module in the second semester of the eighth grade. Each module contained sessions that were designed to be delivered on a weekly basis to foster self-awareness, knowledge, decision-making skills and peer involvement for health behavior change. FLASH behavioral practice incorporated individual and group self-monitoring challenges for eating and activity. Another element of the behavior intervention component was the family outreach strategy for extending changes in physical activity and healthy eating beyond the school day and for supporting the student's lifestyle change choices. Family outreach strategies included the delivery of newsletters and supplemental packages with materials to promote healthy behavior in the home environment during school summer and winter holiday breaks. In conclusion, the HEALTHY behavior intervention component, when integrated with total school food and physical education environmental changes enhanced by communications and promotional campaigns, is a feasible and acceptable mechanism for delivering age-appropriate social learning for healthy eating and physical activity among an ethnically diverse group of middle school students across the United States.

Hereditary complement factor I deficiency

We describe four cases (from three families) of hereditary factor I deficiency, bringing the total number of cases now reported to 23. In one family there are two affected siblings: one has suffered recurrent pyogenic infections; the other is asymptomatic. In the second family, the patient had recurrent pyogenic infections and a self-limiting vasculitic illness; in the third family, the patient suffered recurrent pyogenic and neisserial infections. All four patients had markedly reduced concentrations of C3 in the serum (family 1 propositus: 28%; family 1 asymptomatic sibling: 15%; family 2: 31%; and family 3: 31% normal human serum) which was in the form of C3b. Low IgG2 levels may occur in primary C3 deficiency, and a reduction in IgG2 concentration to 1.14 g/l (normal: 1.30-5.90 g/l) was found in the patient from family 2. Using radioligand binding assays, we demonstrated increased binding of C3b to erythrocytes in a patient with factor I deficiency. This C3b could not be cleaved by autologous serum but could be cleaved by normal serum or purified factor I. We review and compare the published cases of C3, factor H and factor I deficiency.

Quantification of IgG on erythrocytes of patients and normals by a radio-ligand-binding assay

A monoclonal IgG anti-human IgG, 1B12, was used in a radio-ligand-binding assay to quantify IgG on erythrocytes of patients and normals. The assay detected a range of 10-700 IgG molecules. Good correlation was achieved between the number of molecules and the strength of agglutination in antiglobulin tests performed in capillary tubes. The assay was capable of detecting subagglutinating immune bound IgG on erythrocytes from patients with systemic lupus erythematosus (SLE).

Three decades of reference serology

I have tried to show that blood group serology developed rapidly out of necessity and demonstrated a high degree of polymorphism on red cells that was unmatched at that time in man. With new knowledge, these observations have proved to be accurate and informative and correlate well with subsequent biochemical and molecular studies on the antigenic structures, in spite of the fact that they were achieved by relatively simple technology. Serology still has the capacity to focus on points of interest and even to solve problems, albeit in conjunction with other modern and more sophisticated techniques. It provides a good discipline for any scientist to make unbiased and objective studies.

C4 Chido 3 and 6 distinguish two diabetogenic haplotypes: HLA-B49, SC01,DR4,DQw8 and B8,SC01,DR3,DQw2

The combination of the HLA complement allotypes BFS, C2C, C4AQ0 (deleted gene) and C4B1, termed SC01 complotype, usually present in the HLA-B8,DR3,DQw2 diabetogenic haplotype, has also been found in a novel "low frequency" HLA-B49,DR4,DQw8 haplotype associated with Spanish insulin-dependent diabetes mellitus (IDDM). Family studies of C4 antigenic determinants Rodgers/Chido and their specific C4d nucleotide sequences confirm that this novel haplotype bearing Chido -3, -6 is not due to a recent recombination from the common HLA-B8,DR3 haplotype bearing Chido 3,6; moreover, Chido analysis at the serological or DNA level is presently the only way to distinguish both SC01 complotypes, since BF, C2, steroid 21-hydroxylase and C4 genes do not reveal other differences by restriction fragment analysis. On the other hand, HLA-B49,SC01,DR4 is the first DR4-bearing IDDM-susceptible haplotype with a deleted C4 gene described so far and the only DR4-bearing haplotype found in the Spanish population. This report further supports the fact that extended haplotypes with deleted (or "not duplicated") genes in the class III region contain IDDM-susceptibility more often than non-deleted (or "duplicated") haplotypes in the Spanish and other Mediterranean populations.

Immunoblotting human C4 bound to human erythrocytes in vivo and in vitro

A study of C4 bound to human erythrocytes in vitro and in vivo has been made by immunoblotting with mouse monoclonal anti-C4c and anti-C4d and human polyclonal anti-C4d (Rodgers and Chido) following SDS-PAGE. Multi-banded patterns differentiated between C4A and C4B isotypes. Treatment of EC4b with trypsin eliminated immunoblotting but not agglutination reactions. Serum inactivation (factor I) of EC4b resulted in banding patterns similar to those obtained from patients' EC4d. Treatment of EC4b membranes with NH2OH affected many of the bands, two were lost, one was markedly reduced and others had altered SDS-PAGE mobility. Interpretation of the bands has been made in terms of C4-acceptor complexes and inactivation fragments of C4. A distinct difference in the banding of C4A and C4B isotypes has been detected.

In vivo and in vitro binding of C4 molecules on red cells: a correlation of numbers of molecules and agglutination

The fourth component of human complement (C4) is one that is essential to the antibody-mediated classical activation pathway. C4d, present on all normal and most patient red cells (RBCs), may be detected by the human antisera anti-Rodgers (Rg) and -Chido (Ch). A study has been made of the Rg/Ch antigens on normal and patient RBCs in an attempt to understand the mechanism by which C4 is bound to normal RBCs in the absence of RBC antibodies (Abs). Because RBCs from C1q-deficient patients express Rg/Ch, it seems that C1q is not essential for C4 binding. Treatment of normal RBCs with proteolytic enzymes, including trypsin, eliminated positive reactions with anti-Rg/Ch even though the C4d fragment is considered to be resistant to cleavage by trypsin. By correlating agglutination reactions with numbers of bound C4d and C3d molecules, it is evident that both C4d and C3d were affected by trypsin treatment and that anti-Rg/Ch were not capable of agglutinating RBCs with less than 50 molecules of bound C4d. It is concluded that trypsin-sensitive and -insensitive RBC membrane structures may both act as acceptors for C4. RBCs with null phenotypes of the major blood group systems all expressed Rg/Ch antigens, so none of the structures that carry these antigens act preferentially as acceptors for C4.

Erythroid HLA class I expression in 300 patients with haematological, renal and rheumatological disorders

The expression of HLA class I was assessed on erythrocytes by haemagglutination with monoclonal antibodies to monomorphic epitopes on the heavy and light (beta 2-microglobulin) chains. Previously, enhancement of HLA class I expression was observed on erythrocytes of many patients with systemic lupus erythematosus (SLE) and chronic lymphatic leukaemia (CLL), and we have now tested erythrocytes from patients (and 130 normal controls) with other auto-immune diseases and renal and haematological disorders. The striking enhancement in patients with SLE and CLL was confirmed. A significant increase in expression was also observed in aplastic anaemia patients following bone marrow transplantation and in renal patients with primary glomerulonephritis who had received a transplant. No class I was expressed by erythrocytes from many patients with inherited haemoglobinopathies and high reticulocyte counts, which suggests that the enhancement in SLE patients cannot be accounted for by immature or young erythrocyte populations. The distribution of HLA-A and -B types in the patients with enhanced class I expression did not relate to those antigens previously detected more frequently on erythrocytes, B7(Bga), B17(Bgb), A28(Bgc), B8 or A10, and the enhancement was not associated with any particular HLA types.

HLA class I expression on erythrocytes and platelets from patients with systemic lupus erythematosus, rheumatoid arthritis and from normal subjects

It has previously been shown, by a haemagglutination assay, that patients with systemic lupus erythematosus (SLE) express increased levels of HLA class I on erythrocytes compared with normal subjects and patients with rheumatoid arthritis (RA). A radioligand-binding assay, using monoclonal antibody W6/32, was devised to quantify HLA class I expression on erythrocytes and platelets. An increased number of class I molecules was expressed on erythrocytes from 45 patients with SLE (mean = 354 molecules per cell, median = 255 molecules, range = 30-1270 molecules per cell), compared with cells from 46 normal subjects (mean = 132, median = 78, range = 40-550) and 31 RA patients (mean = 132, median = 89, range = 26-497). The presence of HLA-B7 correlated with increased class I expression on erythrocytes from both normal subjects and patients with SLE. Levels of HLA class I in serum were measured. All subjects with HLA-A9 (A23, 24) showed higher levels of serum class I than their A9-negative counterparts, and there was no difference in levels between SLE patients and normal subjects. There were no correlations between class I levels in serum and on erythrocytes amongst SLE patients or normal subjects. Red cells were fractionated, according to their age in vivo, on Percoll gradients. Class I levels fell with increasing erythrocyte age in all individuals, but were higher in all fractions from SLE patients compared with age-matched fractions from normal subjects. HLA-B7-positive erythrocytes also expressed higher class I levels in each Percoll fraction, compared with their HLA-B7-negative counterparts, suggesting that enhanced B7 expression is not due to greater structural stability of this class I allotype. These data are compatible with the hypothesis that class I is expressed as an intrinsic protein of erythrocyte membranes and that expression is increased amongst patients with SLE.

A study of HLA (Bg) on red cells and platelets by immunoblotting with monoclonal antibodies

HLA class I antigens (Bg) on red cells (RBCs) are expressed by some normal donors and by many patients with systemic lupus erythematosus (SLE). To identify the membrane components previously detected by hemagglutination with HLA class I-specific monoclonal antibodies (MoAbs), RBC membrane preparations were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotted with the HLA class I MoAbs. Two components were obtained that reacted with the MoAbs: a heavy chain of 45 kDa and a light chain termed beta2-microglobulin (beta2-M) of 11 kDa. The effect of chloroquine and acid elution in stripping HLA antigens is shown to be due to the removal of beta2-M, as only that component was detected in eluates from reactive RBCs. Neither antibody elution method affected the heavy chain expression assessed by immunoblotting. It is concluded that HLA class I antigens on RBCs are integral membrane components of the type normally found and wisely distributed on many nucleated cells. Platelets, which have stronger HLA class I antigen expression, were also studied, and their membrane preparations yielded heavy chain and beta2-M molecules; the effect of chloroquine treatment was harder to assess than that of acid elution, owing to the sensitivity with which both components are detected in immunoblotting. In eluates obtained from acid treatment only beta2-M is detected.

C4 reference typing report

Human C4 is most polymorphic at the protein level, distinction between allotypes of the C4A and C4B proteins resting on electrophoretic migration patterns and difference in hemolytic activity. The aim of the C4 reference typing has been the definition of reference variants, the assignment of rare variants, and the investigation of duplicated, deleted, or non-expressed and hybrid genes. Samples from 136 individuals, predominantly with known segregation, from 16 laboratories were investigated by standard electrophoretic techniques, for their relative hemolytic activity, reactivity with monoclonal antibodies and Rg/Ch reagents, alpha-, and beta-chain types, relative electrophoretic migration distance, as well as the C4/21-OH-TaqI RFLPs. The results were evaluated in three groups; they consisted in the definition of the eight most common C4 alleles, and the ten Rg/Ch standard phenotypes in group I. In group II twelve C4A and fourteen C4B duplications among 96 complotypes, as well as eighteen deleted/non-expressed C4A and twenty-two C4B alleles, and hybrid alleles were seen by correlation of lytic activity, electrophoretic mobility, and monoclonal and/or Rg/Ch reactivity. Group III consisted of the newly defined allotypes A 8, A 7, A 58, A 55, A 45, B 45, B 35, and B 22, furthermore of alleles subdividing the A 1/A 91, and the B 13/B 12/B 11 regions. The reference typing has allowed reclassification of the majority of described C4 allotypes and resulted in a revision of the C4 nomenclature.

C4 nomenclature statement (1990)

A common and revised nomenclature of the allotypes of the fourth component (C4) of human complement has been proposed. It is based on the results of the C4 Reference Typing of the VIth Complement Genetics Workshop and Conference, Mainz, FRG, 1989, the previous C4 nomenclature and the guidelines for human gene nomenclature (ISGN). The designation of allotypes derives from their relative electrophoretic mobility, the distinction between C4A and C4B proteins from their relative hemolytic activity. Common alleles retain their single digit numeric designation, intermediate variants their two- or three-digit designations; newly discovered alleles should not interfere with already described variants. At least 13 C4A alleles, 16 C4B alleles as well as non-expressed genes at each C4 locus are presently known. There are also duplicated loci of each C4 gene; they should be designated by repetition of the locus symbol at the haplotype or genotype level. As a phenotype they will be placed in parenthesis without repetition of the locus symbol. Aberrant allotypes or hybrid genes should be explained by a special suffix. No special nomenclature is recommended for restriction fragment length polymorphisms. Their designation should follow the general rules of the ISGN.

Human leukocyte antigens (HLA) class I (Bg) on red cells studied with monoclonal antibodies

Monoclonal antibodies, capable of detecting monomorphic epitopes on HLA class I polypeptides and beta-microglobulin (Beta2-M), have been used by a variety of techniques to ascertain the type of structure detected on red blood cells (RBCs). Hemgglutination with class I monoclonal antibodies confirmed the reported relationship between Bg blood groups and HLA. It also established that the expression of HLA on RBCs which do not have nuclei is not normally strong, but may be enhanced in patients, notably those with systemic lupus erythematosus (SLE). Estimates of the number of class I molecules on mature RBCs by a radioligand-binding assay have confirmed that all HLA-B7 (Bga) individuals have higher numbers but that SLE patients usually have the most (124/RBC). Class I polypeptides were not elevated in the plasma of SLE patients and all RBCs lost molecules on aging in the circulation. These two facts suggest that HLA on RBCs is not acquired from plasma. when RBCs from SLE patients were immunoblotted with monoclonal antibodies, a complete 45 kDa intrinsic transmembrane heavy chain of HLA class I and a light chain of 11 kDa (Beta2-M) were detected. Chloroquine treatment and acid elution of RBCs did not remove HLA class I but only Beta2-M, As most antibodies recognize epitopes that depend on close association of class I with Beta2-M, the lost reactivity of treated RBCs may be understood.

Null alleles of human complement C4. Evidence for pseudogenes at the C4A locus and for gene conversion at the C4B locus

The two genes for the C4A and C4B isotypes of the fourth component of human complement are located in the MHC class III region. Previous studies have demonstrated the unusual expression of C4 genes in the form of aberrant or duplicated haplotypes. Null alleles of C4A or C4B (AQ0 or BQ0) have been defined by the absence of gene products and occur at frequencies of 0.1-0.3. However, only some C4 null alleles are due to gene deletions, the remainder were thought to be nonexpressed genes. We have analyzed the C4 gene structure of 26 individuals lacking either C4A or C4B protein. The DNA of individuals with apparently nonexpressed C4 genes was tested for the presence of C4A- and C4B-specific sequences using restriction fragment analysis and isotype-specific oligonucleotide hybridization of DNA amplified by polymerase chain reaction. All nondeleted AQ0 allels had C4A-specific sequences and may thus be described as pseudogenes, whereas the nondeleted BQ0 alleles had C4A-instead of C4B-specific sequences. Gene conversion is the probable mechanism by which a C4A gene is found at the second C4 locus normally occupied by C4B genes.

C4: Rodgers and Chido typing

Rodgers (Rg) and Chido (Ch)-typing, by means of haemagglutination inhibition, has been performed on 136 plasma/serum samples selected by or submitted to the 1989 Workshop. All were tested for two Rg and six Ch antigenic determinants and a proportion were also tested for WH. The established interrelationships for the antigenic determinants have been fully supported and previously reported associations with C4 allotypes have been maintained. A second example of the Ch phenotype Ch:-1, 2,-3,4,5-6 was detected in an Italian family with the B3 allotype.

An epitope on C4 beta light (L) chains detected by human anti-Rg; its relationship with beta chain polymorphism and MHC associations

Two out of ten Rg-specific antisera tested contain a third antibody specific for the beta chain of C4. Analysis of the beta chains of 66 unrelated individuals by sodium dodecyl sulfate polyacrylamide gel electrophoresis revealed that the epitope detected is located exclusively on the light (L) beta chain. A strong, but incomplete, association between the beta chain epitope and the expression of the Rg:2 determinant on the alpha chain of the same protein was also observed. While H (heavy) and L beta chains were not associated with a particular C4 isotype, previously unrecorded associations of beta chain polymorphism with the DR locus have been established.

HLA class I (Bg) antigens on red cells of SLE patients: a serological study with polyclonal and monoclonal antibodies

The enhanced HLA class I (Bg) on red blood cells (RBC) of many patients with systemic lupus erythematosus has allowed a significant correlation to be made between their HLA-B types and haemagglutination reactivity with lymphocytotoxic anti-HLA-B sera stimulated by pregnancy alone. Therefore the class I expression on these RBC relates to classical, rather than non-classical, class I gene products. Studies of class I expression on RBC by means of monoclonal antibodies (MAb) to epitopes on the heavy polypeptide chain and beta 2-microglobulin (beta 2m) have suggested that the complete extracellular structure is present. The specific effect of chloroquine in 'stripping HLA' from RBC had been assumed to support the concept that HLA class I was adsorbed from plasma. However, from our data, we conclude that HLA class I is an intrinsic membrane component. We suggest that the action of chloroquine is to remove beta 2m alone, which prevents normal class I expression and also results in conformational changes to the class I heavy chain, but that it is not capable of removing the membrane-bound heavy chain.

An update on Rodgers and Chido, the antigenic determinants of human C4

Rodgers (Rg) and Chido (Ch) blood groups are antigenic determinants of the fourth component of human complement (C4). Nine determinants have been defined by means of hemagglutination-inhibition (HAI) with polyspecific human antiserums. The association of C4A isotypes with Rg and of C4B isotypes with Ch is strong hut not complete. Derived amino acid sequences from the C4d region of selected C4 allotypes of known antigenic expression have provided support for the previously reported complex serologic interrelationships. A structural model for antigenic determinants at four polymorphic sites, incorporating sequential and conformational epitopes, was subsequently proposed. Allotype and Rg/Ch data obtained from donors and patients, many with accompanying families, have augmented the model and revealed no exceptions. The antigenic determinants, therefore, make an important contribution to the complex polymorphism of C4.

A new low-frequency antigen BOW (Bowyer)

BOW is a 'new' low-frequency red-cell antigen, detected in 2 unrelated English blood donors, that is sensitive to alpha-chymotrypsin and pronase. Anti-BOW is present in many polyspecific reagents used to define low-frequency antigens. Red-cell groups of the proposita, R.B., and her family show that the BOW blood group segregates independently from the ABO, Rh, MNSs, P1 and Kell blood group systems.

The antigenic determinants, Rg/Ch/WH, expressed by Japanese C4 allotypes

The expression of antigenic determinants, Rg/Ch/WH, on Japanese C4 allotypes has been studied. Although the Japanese C4 allotype frequencies are known to differ from Europeans, the antigenic expression of their C4 allotypes correlates with associations described previously. All 89 random donors and 17 selected donors were Rg:1,2 so neither Rg:1,-2 nor Rg:1,-2 was found. The frequency of Ch:1,-2,3 was elevated while that of Ch:1,2,3 was reduced, which was seen as a direct result of the higher frequency of B2 and B5 allotypes. None of the Japanese were Ch:1,2,-3, but this can be accounted for by the absence of the A*6,B*1 haplotype. The WH determinant, which has been associated completely with Rg:1,-2 in Caucasians, was found at a higher frequency, 32%, in association with an A*3,2,B*QO haplotype expressing Rg:1,2, which has not been described previously. Detailed investigation showed that the A3 allotype was Rg:1,2 whereas the A2 allotype only expressed Rg1 (Rg:1,-2 WH+).

Antigenic determinants expressed by human C4 allotypes; a study of 325 families provides evidence for the structural antigenic model

The antigenic determinants of human C4 have been defined by human IgG antisera, Rodgers (Rg) and Chido (Ch), in hemagglutination-inhibition assays (HAI). Eight (2 Rg and 6 Ch) are of high frequency, greater than 90%, and 1, WH, is of low frequency, 15%. The phenotypic combinations are complex; generally, C4A expresses Rg, and C4B has Ch, but reverse antigenicities have been established both by HAI and by sequence data of selected C4 allotypes. A study of 325 families provides data on the antigenic expression of each C4 allotype and demonstrates strong associations. A structural model for the antigenic determinants of C4 proteins has been proposed and is completely supported by the family material. Of the 16 possible antigenic combinations for C4 proteins, only 3 are undetected. A new Ch combination has been recorded in two French families. The reported sequence variation within the C4d region can account for the antigenic determinants but leaves the location of electrophoretic variation in C4 still unclear.

The study of a French family with two duplicated C4A haplotypes

The finding of two duplicated C4A haplotypes in a normal French family led to a detailed study of their C4 polymorphism. The father had an extremely rare A*6A*11, B*QO haplotype inherited by all of his children and the mother had the more common A*3A*2, B*QO haplotype. Two HLA identical daughters only have four C4A alleles. The father's A11 allotype expresses Ch:1 (Chido) rather than Rg:1 (Rodgers) and represents a new Ch phenotype Ch:1,-2,-3,-4,-5,-6. In order to clarify the genetic background in this unusual family, DNA studies of restriction fragment length polymorphisms (RFLPs) were undertaken. The father's rare haplotype, which expresses two C4A allotypes, results from a long and a short C4 gene normally associated with the A*6, B*1 that also exhibits the Bg/II RFLP. As it travels in an extended MHC haplotype HLA A2, B57(17), C2*C, BF*S, DR7 that is most frequently associated with A*6, B*1, we postulate that the short C4B has been converted in the alpha chain region to a C4A gene which produces a C4A protein. This report of a short C4A gene is the first example in the complex polymorphism of C4.

There are two C4 genetic loci and a null allele in the chimpanzee

Genetic polymorphism in C4 in the chimpanzee was studied by agarose gel electrophoresis of desialated plasma and development of patterns by immunofixation with antiserum to human C4 and by a C4-sensitive hemolytic overlay. In general, immunofixation patterns showed multiple partially overlapping bands of which only the most cathodal had strong hemolytic activity. In analogy to human C4, the latter were designated C4B, whereas those detected by immunofixation which had little hemolytic activity were designated C4A. Chimp C4A and C4B reacted with human and mouse (monoclonal) anti-C4B and human anti-Ch1 but neither reacted with monoclonal anti-C4A or human anti-Ch2, Ch3, Rg1, or Rg2. On sodium dodecyl sulfate polyacrylamide gel electrophoresis, the alpha chain of C4B showed a slightly lower apparent relative mass than that of C4A at around Mr 93,000. There were three C4A variants and two C4B variants inherited in families as autosomal codominant traits, as C4A-C4B cosegregating pairs with no detectable crossing-over. These pairs were inherited with chimpanzee leukocyte antigen types C2 and BF variants without detectable crossing-over. Half-null C4 haplotypes with C4B QO were observed in family studies. Nine BF, C2, C4A, C4B allelic haplotypic combinations (complotypes) were identified among presumably unrelated chimpanzees.

Expression of MHC class I determinants on erythrocytes of SLE patients

Strong expression of MHC Class I determinants had been observed on the erythrocytes of three genetically C4 deficient patients who all had SLE. In a study of 35 other SLE patients who were not C4 deficient, 30 showed a marked increase in the expression of MHC Class I on their erythrocytes. There was a correlation between the expression of erythrocyte Class I and disease activity. The polymorphic HLA determinants were detected by haemagglutination with human cytotoxic antisera from untransfused pregnant women. A shared monomorphic epitope of HLA-A, -B and -C, and beta 2-microglobulin were detected by haemagglutination with monoclonal antibodies. A monoclonal antibody for a monomorphic epitope on MHC Class II alpha and beta chains did not react. Erythrocytes from a group of RA patients and a group of normal controls had moderate and low expression respectively. We suggest that MHC Class I may be induced on erythrocytes maturing in a milieu containing mediators derived from activated cells of the immune system. Aberrant tissue expression of MHC antigens may be more widespread than has been previously recognized in diseases mediated by immune mechanisms.

Allo-anti-Chido in a Ch-positive patient

Allo-anti-Chido (Ch) was detected in a patient whose red cells typed as Ch+. The C4 allotype of the patient was A4,B2 which associates strongly with the Ch phenotype Ch:1,-2,3,4,-5,6. Anti-Ch2 + Ch5 were the Ch specificities identified. Absence of only Ch2 and Ch5 determinants on the C4B protein allowed this unique immune response to blood transfusion.

Three Chido determinants detected on the B5Rg+ allotype of human C4: their expression in Ch-typed donors and families

A study was made of polyspecific human allo-anti-C4, anti-Chido (Ch), which reacts with determinants usually located on C4B protein. Some anti-Ch reagents are capable of reacting with Ch- red cells coated with C4 from Ch:-1,-2,-3 donors. A complex serologic pattern demonstrated three more Ch determinants, Ch4, Ch5, and Ch6, which were detected by haemagglutination-inhibition tests. All Ch:1,2,3 samples were Ch:4,5,6 but samples lacking one or more of the Ch1,Ch2,Ch3 series of determinants also lacked some of the new determinants. MHC typed families demonstrated the inheritance of the new determinants as part of the Ch haplotype, and associations with C4 allotypes and haplotypes have been established. Ch4 always associates with C4B protein. Ch5 and Ch6, normally detected on C4B protein, were detected in several individuals who lacked C4B (BQO allotypes) and were therefore presumed in these instances to be located on the accompanying C4A protein.