1. Catherine J. Lillehoj, Ph.D. 1, Jennifer Thorud, MPH 2, Debra Kane, Ph.D. 2 138th Annual American Public Health Association Conference November 9, 2010 1 Bureau of Nutrition & Health Promotion, 2 Bureau of Family Health, Iowa Department of Public Health, Des Moines, IA 50319

2. Objectives Determine prevalence rate of overweight/obesity among Iowa elementary school students Determine predictors of overweight/obesity among Iowa elementary school students

3. Definitions Body Mass Index (BMI) calculated weight & height. BMI reliable indicator of childhood overweight/ obesity. Inexpensive & easy-to-perform method to screen for weight categories that may lead to health problems. For children, BMI is age- & sex-specific; often referred to as BMI-for-age. CDC & American Academy of Pediatrics recommend BMI to screen for childhood overweight & obesity beginning at 2 years old.

4. Current Data Sources Pediatric Nutrition Surveillance System Children birth - 5 years of age Participating in WIC Less than 40% of all children in Iowa Youth Risk Behavior Survey Self-reported height & weight Self-reported perception of weight High school age Scanty school participation Pilot Intervention Project/CDC Nutrition & Physical Activity Grant 12 schools (3 rd, 4 th, 5 th graders)

5. Overweight & Obesity Weight Status Category% Range Underweight< 5 th percentile Healthy Weight5 th percentile - < 85 th percentile Overweight85 th - < 95 th percentile Obese> 95 th percentile http://www.cdc.gov/healthyweight/assessing/bmi/childrens_bmi/about_childrens_bmi.html

6. The Obesity Epidemic Over two-thirds of Iowa adults overweight or obese (67.2%); equivalent approximately 1.5 million Iowans (BRFSS, 2009). 2009 national overall overweight and obesity median estimate 63.2% (BRFSS, 2009). Approximately 11% Iowa youth (9th–12th grades) considered obese; 13% considered overweight (Youth Risk Behavior Survey, 2007). Among Iowa 3rd, 4th, 5th grade students, 61.2% normal BMI; 23.5% overweight; 15.8 % obese (Spring, 2009). Nationally, prevalence of obesity among children (6 - 11 years) increased in past 3 decades from 6.5% to 19.6%. Prevalence of obesity among adolescents (12 - 19 years) (same time frame) increased from 5.0% to 18.1%. http://www.cdc.gov/HealthyYouth/obesity/index.htm

7. Screening Procedure Equipment Properly calibrated scale (digital) Note: To maintain accuracy, scales periodically validated; recalibrate as needed. Device to measure height (stadiometer) Body Mass Index-for-Age Percentiles –CDC 2009 version) Tool for determining BMI CDC BMI Table at: http://www.cdc.gov/nccdphp/dnpa/bmi/00binaries/bmi- tables.pdf Computer application (e.g., SPSS)

8. Procedure Students weighed & measured in setting that provides privacy. Confidentiality always important; care should be taken findings not accessible to other students or shared with staff. Students react in variety of ways to being weighed & measured at school. Girls often concerned about being overweight regardless of actual size. Boys worry about being short & too thin. During screening, neutral comments like “Kids bodies come in different sizes and shapes” are encouraged. Screeners should be objective, calm & open to students’ concerns. Some students may need to meet with school nurse at a later time to discuss their concerns.

9. Analyses Mixed modeling to control for student nesting within schools conducted with SPSS; fixed & random effects “School” incorporated as a random effect to control for the nested sample (individuals within schools) Overall model fit assessed with F-test statistic Sugar sweetened beverage (SSB) consumption coded 0 – 2+

10. Results Sample Background Characteristics Reliable BMI calculations obtained 1,143 students 2009-2010 school year. Participation rate 79%. Most common reason for lack of calculated BMI was absence from school assessment day (10% of students). 8% of parents refused their child’s participation, 3% of students refused to participate. 51% were boys. Mean age 8.5 years. Race: 91.8% White 4.2% Hispanic 4% Other

11. Results, contd. Only 61% considered to be healthy weight for their height & age More than 20% (21.7%) were 95th BMI percentile or above (by definition should include only 5% of students) 15% in 85th - 94th BMI percentiles, considered overweight About 2% (1.7%) were underweight Across different groups, 52% Hispanic students, 57% African American students, 62% Caucasian students were at healthy weight Males somewhat heavier than females (61.5% vs. 61.1%)

12. Results, contd. Students who participated in Free or Reduced Lunch (F/RL) higher BMI scores (r= –.08, p <.01). Mixed modeling analysis, controlling for student nesting within schools, found F/RL & SSB significantly predicted BMI (F = 5.3, p <.05). Two-way interaction between gender (boys) & SSB significantly predicted BMI (F = 3.0, p <.05).

13. Results, contd.

14. BMI & Consumption of Sugar Sweetened Beverages among Iowa 3 rd Graders, 2010 BMI0 SSB serving 1 SSB serving > 2 SSB servings Normal weight19%31%19% Overweight/ Obese 8%13%11% 24% Iowa 3 rd grade students who consumed > 1 SSB daily were overweight or obese.

15. Conclusions BMI assessment program has shown some success in raising school nurses’ awareness of benefits measuring student BMI. Survey of Iowa school nurses found 3 themes related to benefits : Create awareness of overweight/obesity issue (73.9%) Information gained used to change school policy (60.9%) Create coordinated effort to address the issue of overweight/obesity (56.5%)

16. Survey of Iowa school nurses found most had been measuring student height & weight without school mandates or policies. Most school nurses had not developed or implemented school programs to address issue. School nurses were not confident in ability to use BMI data to convince administrators to implement programs to help students maintain healthy weight; 36.4% reported “Slightly Confident” or “Not Confident.” Conclusions, contd.

17. Only 61% considered to be healthy weight for their height & age 52% Hispanic students, 57% African American students, 62% Caucasian students were at healthy weight 24% Iowa 3 rd grade students who consumed > 1 SSB daily were overweight or obese Mixed modeling analysis, controlling for student nesting within schools, found F/RL & SSB significantly predicted BMI Two-way interaction between gender (boys) & SSB significantly predicted BMI

18. Public Health Implications Need to build on strengths of programs that reach & conduct surveillance of overweight/obesity among Iowa children Examine strategies to reach & serve overweight/ obese Iowa children especially groups at higher risk (e.g., rural schools) Examine collaborating with school nurses to reach students & parent that may want added resources.