Using the Body Mass Index (BMI)-for-age Growth Charts: A Training for Health Care Provider Assistants Adapted by the CHDP Bay Area Nutrition Subcommittee

Using the Body Mass Index (BMI)-for-age Growth Charts:

A Training for Health Care Provider Assistants

Adapted by the CHDP Bay Area Nutrition Subcommittee (BANS) from

Centers for Disease Control and PreventionNational Center for Chronic Disease Prevention and Health

Promotion

Division of Nutrition and Physical Activity

Maternal and Child Nutrition BranchJanuary 2006

Training ObjectivesTraining Objectives

Understand BMI and its Understand BMI and its importance for health care importance for health care providers providers

Learn how to plot BMI on the Learn how to plot BMI on the BMI-for-age growth chartsBMI-for-age growth charts

Source: Behavioral Risk Factor Surveillance System, CDC.

Obesity Trends* Among U.S. AdultsBRFSS, 1985

No Data <10% 10%–14%

(*BMI ≥30, or ~ 30 lbs overweight for 5’ 4” person)



No Data <10% 10%–14%




No Data <10% 10%–14%




No Data <10% 10%–14%




No Data <10% 10%–14%




No Data <10% 10%–14%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19%




No Data <10% 10%–14% 15%–19% ≥20




No Data <10% 10%–14% 15%–19% ≥20




No Data <10% 10%–14% 15%–19% ≥20




No Data <10% 10%–14% 15%–19% ≥20




No Data <10% 10%–14% 15%–19% 20%–24% ≥25%



(*BMI 30, or ~ 30 lbs overweight for 5’4” person)

No Data <10% 10%–14% 15%–19% 20%–24% ≥25%




Obesity* Trends Among U.S. AdultsBRFSS, 2003


No Data <10% 10%–14% 15%–19% 20%–24% ≥25%

How many…?How many…?

20002000 20052005

Nine Million Kids Nine Million Kids are Overweightare Overweight

Hispanic 22.50%

Asian/PI 11.90%

Black15.60%

0%

10%

20%

30%

40%

50%HispanicAsian/PIBlackWhiteAll Races

All Races

17.90%

not

en

ough

dat

a

Pediatric Nutrition Surveillance System (PedNSS) Growth Pediatric Nutrition Surveillance System (PedNSS) Growth Statistics forStatistics for

City and County of San Francisco 2004City and County of San Francisco 2004BMI for age > 95% for Children 2-4 YearsBMI for age > 95% for Children 2-4 Years

Hispanic 26.60%

Asian/PI 11.40%

Black 24.90%

0%

10%

20%

30%

40%

50%HispanicAsian/PIBlackWhiteAll Races

All Races

19.20%

White 17.90%

Pediatric Nutrition Surveillance System (PedNSS) Growth Pediatric Nutrition Surveillance System (PedNSS) Growth Statistics forStatistics for

City and County of San Francisco 2004City and County of San Francisco 2004BMI for age > 95% for Children 5-19 YearsBMI for age > 95% for Children 5-19 Years

A number that compares a child’s A number that compares a child’s weight to her heightweight to her height

Body Mass Index (BMI) = Body Mass Index (BMI) =

Weight (kg) / Height (m)²Weight (kg) / Height (m)²

BMI is an effective BMI is an effective SCREENING test test to check for possible overweight; to check for possible overweight; but alone it is notbut alone it is not a diagnostic toola diagnostic tool

What is BMI?What is BMI?

BMI is Only an Indirect BMI is Only an Indirect Measure of Body FatMeasure of Body Fat

BMI is Not the Same for BMI is Not the Same for Adults and ChildrenAdults and Children

Adult BMI is evaluated by use of Adult BMI is evaluated by use of cut-off numbers; for example BMI cut-off numbers; for example BMI >30 is indicative of adult obesity>30 is indicative of adult obesity

The BMI for children is useful The BMI for children is useful only when it is plotted on the only when it is plotted on the “BMI-for-age Growth Chart”“BMI-for-age Growth Chart”

Example: 95th percentile tracking Age BMI 2 yrs 19.3 4 yrs 17.8 9 yrs 21.013 yrs 25.1

For Children, BMI Changes with Age

Boys: 2 to 20 years

BMI BMI

BMI BMI

Associated with clinical risk Associated with clinical risk factors for chronic disease factors for chronic disease including hyperlipidemia, including hyperlipidemia, elevated insulin, and high elevated insulin, and high blood pressureblood pressure

Importance of Using Importance of Using BMI-for-ageBMI-for-age

CDC CDC StandardizeStandardized d Growth Growth ChartChart

Formula to calculate BMI

Published May 30, 2000

Percentiles (5th,10th,25th, 50th, 75th,85th,90th,95th)

What is a What is a Percentile?Percentile?

95th

5th

50th Percentile

85th

> 95th percentile Overweight

85th to < 95th Risk of percentileoverweight

< 5th percentileUnderweight

Using BMI-for-age Percentiles to Assess Risk

Steps to Plot BMI-for-ageSteps to Plot BMI-for-age1.1. Obtain accurate weight and Obtain accurate weight and

height measurements height measurements

2.2. Select the appropriate Select the appropriate growth chartgrowth chart

3.3. Record the dataRecord the data

4.4. Calculate BMICalculate BMI

5.5. Plot measurementsPlot measurements

5 year old boy

Weight: 43.5 lb

Height: 43 in

BMI= 16.5

BMI-for-age = 75-84th %tile

Inaccurate height measurement: 42.5 in

BMI=17

BMI-for-age = 85-94th %tile

1. Obtain Accurate Weight and Height Measurements

Accurate Measurements are Critical

Boys: 2 to 20 years

BMI BMI

BMI BMI

2. Select the Appropriate 2. Select the Appropriate Growth ChartGrowth Chart

For ages birth to 36 months old:For ages birth to 36 months old:““Length-for-age,” and “Weight-for-age” Length-for-age,” and “Weight-for-age” ““Weight-for-length,” and “Head Weight-for-length,” and “Head

Circumference-for-age” Circumference-for-age”

For ages 2 to 20 years: For ages 2 to 20 years: ““Weight-for-age,” and “Stature-for-age”Weight-for-age,” and “Stature-for-age”Body Mass Index “BMI-for-age”Body Mass Index “BMI-for-age”

3. Record Data3. Record Data

4. Calculate BMI4. Calculate BMI

English:

Wt (lbs.) ÷Ht (in.) ÷ Ht (in.) x 703

Metric: Wt (kg.) ÷Ht (cm.) ÷ Ht (cm.) x 10,000

4. Calculate BMI4. Calculate BMI

Use a Pediatric BMI WheelUse a Pediatric BMI Wheel

5. Plot Measurements5. Plot Measurements

Age

BMI

50th

75th

85th

5th

95th

Practice using Practice using “BMI-for-age” Growth Chart“BMI-for-age” Growth Chart

Liz (4 y)Pete (3 y) Gabriella (4 y)Photos from UC Berkeley Longitudinal Study, 1973

Please Plot Pete Perfectly

Photo from UC Berkeley Longitudinal Study, 1973

Measurements for Pete:

Age= 3 y 3 wks

Weight= 41 lbs (18.6 kg)

Height= 39.7 in (100.8 cm)

Find BMI and plot.

BMI= Wt ( lbs) ÷ Ht (in) ÷ Ht (in) x 703

BMI=18.3

Boys: 2 to 20 years

BMI BMI

BMI BMI

Answers: Pete’s “BMI-for-age”

Let’s Look at LizLet’s Look at Liz

Liz

Liz’s - BMILiz’s - BMI

Liz

17.7

2-3-02

Graph Gabriella’s Growth Graph Gabriella’s Growth

Gabriella’s BMI Gabriella’s BMI

• For additional training materials related to the growth charts

• For tools related to the growth charts

• To download the growth charts

Please visit:

www.cdc.gov/growthcharts/

Guidelines for Overweight in Adolescent Preventive Services (Am J Clin Nutr 1994;59:307-316)

Obesity Evaluation and Treatment: Expert Committee Recommendations (Pediatrics 1998 Sept;(102)3:e 29)

Assessment of Childhood and Adolescent Obesity: International Obesity Task Force (Am J Clin Nutr 1999, 70,suppl)

Centers for Disease Control and Prevention Website (www.cdc.gov/growthcharts)

American Academy of Pediatrics Policy Statement: Prevention of Pediatric Overweight and Obesity (Pediatrics 2003 Aug (112)2; 424-430)

References

Documents

Using the Body Mass Index (BMI)-for-age Growth Charts: A Training for Health Care Provider Assistants Adapted by the CHDP Bay Area Nutrition Subcommittee