Cost-effectiveness of Obesity Prevention Strategies:
Steve Gortmaker, Ph.D.
Harvard School of Public Health
Childhood Obesity Prevention Coalition
Dec 3, 2013
Supported by grants from CDC (1U48DP001946), including the Nutrition and Obesity Policy,
Research and Evaluation Network, the Robert Wood Johnson Foundation, and the JPB Foundation.
This work is solely the responsibility of the authors and does not represent official views of the
Centers for Disease Control and Prevention or any of the other funders.
Outline for Today
• What changes do we need to alter child
obesity in the US? The energy gap
• Lancet Series: causes, trends and best value
for money policies and programs
• CHOICES cost effectiveness modeling in US
– SSB tax, School based physical activity,
reducing marketing to children
• Recent Boston Initiatives
• Implications for Action
Cover of
The
Economist
the energy gap
Claire Wang & Steve Gortmaker
Energy Gap Framework: Rationale
Excess weight gain during growth is a result of energy
intake exceeding expenditure. Measuring underlying
drivers of population weight shift informs surveillance,
goal setting and benchmarking progress.
Definition:
Imbalance between calories children consume each day
and calories required to support normal growth,
physical activity, and body function.
Reference: Wang YC, Gortmaker SL, Sobol AM, Kuntz KM. Pediatrics 2006. 118 (6): 1721-1733
Translating Excess Weight Gain to
Daily Energy Gap
Assumptions
 3500 kcal accumulated= 1 lb weight gain as fat
 Efficiency of energy storage from food: 50-75%
 Linear accumulation of excess weight over 10 y
 Adjustment for higher energy expenditure following
weight gain
Kcal in
Energy Balance (EB)
Body Weight (Kg)
Kcal out
Average Daily Energy Gap (kcal/day):
1988-94 to1999-2002
All Teens
Excess Weight Gained
(Lb)
Daily Energy Gap
(kcal/day)
10
110 -165
 Behavioral implications of 150 kcal for an average kid:
 Replacing 1 can of soda (12 oz) with water (140 kcal)
 Reducing TV watching by an hour (100 kcal/day)
 Walking ~1.9 hours instead of sitting
 Increasing PE from 1 to 3 times/week (240 kcal)
The Energy Gap and Recent Obesity Trends
Increasing childhood obesity in US
What will it take to halt, or reverse these trends so
we can reach the Healthy People goals?
Wang, Orleans, Gortmaker. (2012) Reaching the Healthy People
Goals for Reducing Childhood Obesity: Closing the Energy Gap. Am
J Prev Med.
64.
Recent work of Hall
• The bodyweight response to a change of
energy intake is slow, with half times of
about 1 year
• An adult with a BMI higher than 35 kg/m²,
(14% of US population), needs a change
greater than 500 kcal per day to return to the
average bodyweight of the 1970s
• Children have much less excess weight!
Hall KD, Sacks G, Chandramohan D, Chow CC, Wang YC, Gortmaker
SL, Swinburn BA. Quantification of the effect of energy imbalance on
bodyweight. Lancet. 2011 Aug 27;378(9793):826-37.
Science, Policy and Action
•Governments need to lead obesity prevention, but
so far few have shown leadership
•It is crazy that we do effectiveness studies and do
not measure intervention costs
•Empirical evidence of how to prevent obesity is
limited but growing: cost-effectiveness policy and
program analyses indicate several are both
effective and cost saving
Gortmaker, Swinburn, Levy et al. Changing the future of obesity: science,
policy, and action, Lancet 2011; 378: 838–47.
Evidence for Leveling Off Childhood
Overweight/Obesity Rates
 Happening all over US
 In MA 2009-2012 75% of school districts had
decreasing trend1
 Boston rates 2009-11 decline from 42.6 to 39.9
(N of 12,000/year)
 =>Evidence for change – but rates still at
historically high levels
1 Wenjun Li, James Buszkiewicz, Robert Leibowitz, Anne Sheetz, Laura York, Thomas Land. Trends in
overweight and obesity prevalence in Massachusetts school districts (2009-2013). Poster presented at New Balance
Obesity Conference, Boston, MA 2013.
2 The Status of Childhood Weight in Massachusetts, 2011. Preliminary Results from Body Mass Index Screening
in Massachusetts Public School Districts, 2009-2011. Massachusetts Department of Public Health. 2012.
CHOICES Pilot Study
Modeling the Cost Effectiveness of
Childhood Obesity Interventions in the
United States
Why Cost Effectiveness?
When you talk to decision makers about your
work (what you can do to improve childhood
obesity), they want to know three things
• What is feasible (the intervention,
program, policy)?
• How effective is it?
• What will it cost?
Cost-effectiveness Plane
Difference in Cost
+
Higher costs
Worse outcome
Higher costs
Better outcome
-
+
Lower costs
Worse outcome
Lower costs
Better outcome
Difference in Effectiveness
Why Cost Effectiveness?
We cannot afford all the childhood obesity
interventions we’d like to implement, so why
not begin with those producing the “biggest
bang for the buck?”
Pilot Cost-effectiveness Models
•
•
•
Originally funded by Robert Wood Johnson
Foundation
Adapted Australian ACE (Assessing Cost
Effectiveness) methodology
• ACE Prevention and ACE Obesity
Continued work with JPB funding
• CHOICES project (CHildhood ObesIty Cost
Effectiveness Study)
CHOICES Team for Pilot
• Harvard (Gortmaker, Cradock, Giles,
Weinstein, Resch, Ward, Long, Barrett,
Sonneville, Wright)
• Columbia University (Wang)
• Deakin (Swinburn, Carter, Moodie, Sacks)
• Queensland (Vos, Barendregt)
Key Methods in CHOICES
• Recruitment of a stakeholder group
• Selection of interventions
• Specification of the Intervention,
implementation and costing
• Intervention effects evidence synthesis
• Modeling short and long term cost
effectiveness
• Uncertainty and sensitivity analyses
• Implementation and equity considerations
Recruitment of Stakeholder Group
•
•
•
•
US policy makers and researchers
Nutrition/physical activity researchers
Programmatic experts
Provide advice on specification of
interventions, data sources,
implementation
Selection of Interventions
• Selected by investigators, with stakeholder
input
• Both nutrition and physical activity
interventions
• Both policy and programmatic
• Interventions can be clearly specified
• Can be spread throughout US
The CHOICES Logic Model
Intervention
recruitment
Intervention
Implementation
BMI and
Obesity
DALYS
QALYS
Health care
costs
averted
Intervention, Effects, and Costing
Intervention
recruitment
Intervention
Implementation
Costs of
• intervention
• current practice
BMI and
Obesity
Short term
outcomes:
$cost/BMI
DALYS
QALYS
Health care
costs
averted
Long term
Outcomes:
health care
offsets
$cost/DALY
Intervention, Effects, and Costing
Intervention
recruitment
Intervention
Implementation
Costs of
• intervention
• current practice
BMI and
Obesity
Short term
outcomes:
$cost/BMI
DALYS
QALYS
Health care
costs
averted
Long term
Outcomes:
health care
offsets
$cost/DALY
Intervention, Effects, and Costing
Intervention
recruitment
Intervention
Implementation
Costs of
• intervention
• current practice
BMI and
Obesity
Short term
outcomes:
$cost/BMI
DALYS
QALYS
Health care
costs
averted
Long term
Outcomes:
health care
offsets
$cost/DALY
Intervention, Effects, and Costing
Intervention
recruitment
Intervention
Implementation
Costs of
• intervention
• current practice
BMI and
Obesity
Short term
outcomes:
$cost/BMI
DALYS
QALYS
Health care
costs
averted
Long term
Outcomes:
health care
offsets
$cost/DALY
Implementation and Equity Considerations
•
•
•
•
•
•
•
Level of evidence (pathway to BMI)
Equity and impact on disparities
Acceptability to stakeholders
Feasibility
Sustainability
Side effects
Social and policy norms
Evidence from Pilot Interventions

Potential Impact of a Sugar-sweetened Beverage Excise Tax
on BMI, Disability Adjusted Life Years, and Healthcare Costs
in the United States (Long)

Cost-effectiveness of a state policy requiring minimum
levels of moderate-to-vigorous physical activity during
elementary school physical education classes (Barrett)

Potential Impact of Eliminating the Tax Subsidy of Food and
Beverage Television Advertising Directed at Children and
Adolescents on BMI, DALYs, and Healthcare Costs in the
United States (Sonneville)
SSB Excise Tax Intervention
 In
2012 8 states and 2 cities considered
legislation to increase SSB taxes, although
none passed1
 The modeled intervention consists of:
An excise tax of one cent per ounce of SSB,
applied nationally and administered at the
state level
1
Yale Rudd Center SSB Excise Tax Map, 2012
29
Active PE Intervention
Implementation of a state policy directing the U.S.
state boards of education to include a requirement
for 50% of PE time to be devoted to MVPA in the
state PE curriculum for the elementary school level

Based on policies passed by state legislatures in
Texas (SB 891, 2009) & Oklahoma (SB 1876, 2010)

Implemented within existing PE time provided

Children are exposed on ~2 days/week during the
school year from the ages of 5-11 years
30
TV Advertising Intervention
 Eliminate
the tax deductibility of TV
advertising costs for nutritionally poor
foods and beverages advertised to
children and adolescents ages 2-19
Conduct uncertainty and scenario analyses
• Computer simulation model 2005 US population
• Use @Risk and compiled programming model for
uncertainty analyses: 10,000 iterations
• Short-term Outcomes: Effects on BMI compared
to natural history
• Long-term Outcomes: BMI-mediated reductions
in incidence of 9 diseases
• Estimated disability-adjusted life years (DALYs)
averted and healthcare cost savings
• Discounted health effects and costs at 3.5%
Comparison of Results
•
•
All interventions show evidence for
effectiveness
Widely varying:
• Reach (population)
• Total cost of intervention
• Per person BMI change (those in the
intervention)
• Short Term Cost effectiveness ($cost/BMI)
Overview of Short Term Outcomes
Intervention
Reach
Millions
Total Cost Per
US $
Person
Millions
BMI Unit
Reduction
Cost per
unit BMI
reduction
US$
Age 2-19
SSB Excise Tax
(all ages)
287
$147
0.19
$6.44
Active PE in
School (age 5-11)
16.6
$54.7
0.02
$191
$0.8
0.13
$0.08
TV Advertising
74
Change (age 2-19)
Overview of Short Term Outcomes
Intervention
Reach
Millions
Total Cost Per
US $
Person
Millions
BMI Unit
Reduction
Cost per
unit BMI
reduction
US$
Age 2-19
SSB Excise Tax
(all ages)
287
$147
0.19
$6.44
Active PE in
School (age 5-11)
16.6
$54.7
0.02
$191
$0.8
0.13
$0.08
TV Advertising
74
Change (age 2-19)
Overview of Short Term Outcomes
Intervention
Reach
Millions
Total Cost Per
US $
Person
Millions
BMI Unit
Reduction
Cost per
unit BMI
reduction
US$
Age 2-19
SSB Excise Tax
(all ages)
287
$147
0.19
$6.44
Active PE in
School (age 5-11)
16.6
$54.7
0.02
$191
$0.8
0.13
$0.08
TV Advertising
74
Change (age 2-19)
Overview of Short Term Outcomes
Intervention
Reach
Millions
Total Cost Per
US $
Person
Millions
BMI Unit
Reduction
Cost per
unit BMI
reduction
US$
Age 2-19
SSB Excise Tax
(all ages)
287
$147
0.19
$6.44
Active PE in
School (age 5-11)
16.6
$54.7
0.02
$191.00
$0.8
0.13
$0.08
TV Advertising
74
Change (age 2-19)
Comparison to Clinical Interventions
High Five Intervention: $1000/BMI unit change1
Bariatric Surgery: One estimate can be derived
by assessing the average cost divided by
average change in BMI.2-3 This indicates a cost
of about $3000/BMI unit change
•
•
1 Wright,
et al. Paper under review
Kelleher DC, Merrill CT, Cottrell LT, Nadler EP, Burd RS. Recent national trends in the use of adolescent inpatient bariatric
surgery: 2000 through 2009. JAMA Pediatr. 2013;167(2):126-132.
3 Black JA, White B, Viner RM, Simmons RK. Bariatric surgery for obese children and adolescents: a systematic review and
meta-analysis. Obes Rev. 2013.
2
Long-term Outcomes: SSB Excise Tax
Tax would be cost saving within 1 year of
reaching full effect
 Assuming effects would be maintained
indefinitely:

Life-Years Saved
DALYs Averted
4.49 million
5.56 million
Healthcare costs saved $47.1 billion
Healthcare costs saved $321
per dollar spent
39
Long Term Outcomes:
Childhood Interventions
•
Long term cost-effectiveness and cost
saving for childhood interventions require
maintenance of effect for many years (30+)
under current modeling assumptions
Additional Benefit: Revenue!
Intervention
Increased National
Revenue per year
US$
SSB Excise Tax
(all ages)
$12.4 billion/year
Active PE in School
(age 5-11)
TV Advertising Change
(age 2-9)
$356 million/year
Health Equity: SSB Excise Tax
Concerns regarding potentially regressive nature of
SSB excise tax have been raised
 Empirical evidence on soda taxes demonstrates
greater benefit for overweight children and children
in African-American and low-income households1
 Substantial revenue can be earmarked for
progressive nutrition and public health programs

1 Sturm
et al. Health Affairs. 2010;29(5):1052-1058
42
Equity Considerations: PE Intervention

PE time requirements may not be as likely in
schools with higher percentages of low income
students
- Johnston et al. 2007; San Diego State University 2007

So an Active PE policy may have a greater impact
among higher income students who have more PE
time, and be less likely to reach lower income
students

Therefore, potentially inequitable in terms of
socioeconomic status
43
Equity Considerations: TV Advertising

Because low income and ethnic minority children
watch more TV, there is the potential to reduce
obesity disparities and related health outcomes via
this intervention
44
40 CHOICES Cost Effectiveness Studies

Study Goals:
• To generate cost effectiveness estimates for 40 of the
most relevant childhood obesity interventions in the
United States;
• Using comparable methods
• To engage policymakers and the general public in this
issue, and provide guidance so that the most cost
effective strategies for action are identified and become
a focus of discussion and action.
Some New Environmental Change
Strategies in Boston:
Get Sugar Sweetened Beverages Out of
Schools, Preschools, Afterschools,
Government Worksites, Healthcare
Institutions – and Assure Water Access
Reported Consumption of Servings (12 oz)
per Day of Sugary Drinks, Boston High
School Youth - Before and After
Implementation of School Beverage Policy
1.68
1.40
1.8
1.6
1.4
1.2
Change in
Boston P<0.001;
no change in
national sample
1
Boston High School Youth
0.8
0.6
0.4
0.2
0
2004 Pre
2006 Post
Boston Youth Survey data were collected via a collaboration between the City of
Boston and Harvard School of Public Health. N=1079 in 2004 and 1223 in 2006
OSNAP Initiative
• PRC 2010-2014 core research project
• In partnership with Boston Public Schools,
YMCA of Greater Boston, Boston Boys and Girls
Clubs, Boston Centers for Youth and Families,
Boston Public Health Commission
• Builds on PRC work with YMCA of the USA, BPS
Food and Nutrition Services
48
Goals for Nutrition and Physical
Activity in Out-of-School Time
•
•
•
•
•
•
•
•
•
Include 30 minutes of moderate, fun, physical activity for every
child every day
Offer 20 minutes of vigorous physical activity 3 times per week
Ban sugar-sweetened drinks from snacks served
Offer water as a drink at snack every day
Eliminate use of commercial broadcast TV/movies
Limit recreational computer time to less than one hour per day
Offer a fruit or vegetable option every day at snack
Ban foods with trans fats from snacks served
Ban sugar-sweetened drinks brought in from outside the snack
program
Out of School Nutrition and
Physical Activity Initiative
Serving water during afterschool: Impact
of Group Randomized Trial
Catherine Giles, Erica Kenney, Steven Gortmaker, Rebekka
Lee, Julie Thayer, Helen Mont-Ferguson, Angie Cradock
RCT: Fall 2010-Spring 2011
• 20 afterschool programs in Boston
• Matched pairs (program partners, lunch
provider, demographics, PA facilities)
• 5 days of data collection pre/post
• 1097 children in consent pool in Fall
• Snack intake collected on 590 students in Fall
• Accelerometer data collected on 568 students
in Fall
OSNAP Impact
• Intervention effects: increases in times water served
per day (0.59; p<0.001) and ounces of water served
per day (3.33: P<0.001)
• The intervention resulted in a 76.0 kcal decrease in
beverages offered (p<0.001), mainly by replacing
juice with water (servings of milk were unaffected).
• Check out the materials: www.osnap.org
– Assessments - Interactive Action Planning
– Step-by-Step Topic Specific Guides - Implementation Guides
Giles CM, Kenney EL, Gortmaker SL, Lee RM, Thayer JC, Mont-Ferguson H, Cradock AL.
Am J Prev Med. 2012 Sep;43(3 Suppl 2):S136-42.
Menino expands sugary drink ban
Some beverages won’t be allowed on city properties
A Coca-Cola machine in front of the Boston Fire Department’s station on Columbus Avenue in the South End. (John
Tlumacki/Globe Staff)
By Meghan E. Irons
Globe Staff / April 8, 2011
Can Cost Effectiveness Research Help to
Reverse the Obesity Epidemic?
•Note the first success in tobacco control in retrospect was
not really that complex and cost effective strategies were
key: reduce marketing, raise taxes to increase price,
restrict consumption in public places, combined with
some treatment…..these together had a substantial impact
•We can alter the course of the obesity epidemic –
evidence seems to indicate that policy and regulatory
strategies are key and that cost effectiveness evaluation
can be critical so efforts is targeted
•Strategies to lower sugar sweetened beverage access
should be central to any obesity control strategy