Comorbidities, Health Care Use, Health Care Costs, and

Health Behaviors by BMI

Suzanne M. GoodwinDoctoral Candidate

Department of Health Policy and ManagementJohns Hopkins Bloomberg School of Public Health

sgoodwin@jhsph.edu

AcademyHealth Annual Research MeetingJune 10, 2008

2

Obesity in the U.S.

• 34% of adults in U.S. are obese (BMI≥30 kg/m2)

• Obese persons generally have more comorbidities and higher health care costs and utilization than nonobese

3

JHU-BCBS Patterns of Obesity Care Study

• Partnership with Johns Hopkins University, Blue Cross Blue Shield Association, and 7 BCBS plans

• Evaluate health care utilization, cost and obesity treatment outcomes among 7 BCBS plans

• 2002-5 claims data on selected plan enrollees

– Health Risk Assessment data from 3 plans

4

Study Purpose

• To assess the association between BMI and comorbidities, health care utilization, health care costs and health behaviors among a large cohort of individuals enrolled in 3 BCBS plans

*** Preliminary results – work in progress ***

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Study Sample• 71,058 unique HRA respondents

– 56% female

– Mean age: 48.8 years

• Exclusions

– Missing height or weight

– 10<BMI<70

– Age <18

– Pregnancy within 1 year of HRA completion year

– <6 months plan enrollment in HRA completion year

– Extra HRA records for same person

– Bariatric surgery patients

6

Study Data• Members’ HRA data combined with their claims data for

same year

• HRA data

– Height and weight to calculate BMI

– Self-reported health behaviors (e.g., smoking, alcohol use,

exercise)

• Claims data

– ICD and CPT codes

– Paid costs

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BMI DistributionUnderweight2%

Morbidly Obese3%

Normal40%

Overweight35%

Obese20% Underweight

Normal

Overweight

Obese

Morbidly Obese

Mean BMI = 26.7

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Comorbidities by BMI

0%

5%

10%

15%

20%

25%

30%

35%

40%

0

2

4

6

8

10

12

14

16

Normal Overwt Obese Morbid obese

Overwt OR Obese OR Morbid obese OR

Pre

vale

nc

e

Od

ds

Rat

io

Ref: normal

adjusted for sex, age, plan site, and plan type

* p<0.05

*

*

*

*

*

** * *

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Comorbidities by BMI

0%

3%

6%

9%

12%

15%

Cardiaccondition

Asthma Sleepapnea

Cardiaccondition

Asthma Sleepapnea

0

5

10

15

20

25

Normal Overwt Obese Morbid obese

Overwt OR Obese OR Morbid obese OR

Pre

vale

nc

e

Od

ds

Rat

io

Ref: normal

adjusted for sex, age, plan site, and plan type

* p<0.05**

*

*

*

** * *

10

Hospital Stay by BMI

0%

2%

4%

6%

8%

10%

1+ hospital stay 1+ hospital stay OR

0

0.3

0.6

0.9

1.2

1.5

Normal Overwt Obese Morbid obese

Overwt OR Obese OR Morbid obese OR

Od

ds

Rat

io

Ref: normal

adjusted for sex, age, plan site, plan type, and 6 comorbidities

* p<0.05

**

*

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Health Care Costs by BMI

$0

$1,000

$2,000

$3,000

$4,000

TOTAL Hospital Prof Rx

Normal Overweight Obese Morbidly Obese

Sta

nd

ard

ize

d M

ean

Co

sts

b

ase

d o

n R

VU

s

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Health Behaviors by BMI

0%

10%

20%

30%

40%

50%

Exercise (N=32,147) Smoking (N=22,444) Alcohol (N=44,473)

Normal Overweight Obese Morbidly Obese

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Health Behaviors by BMI

0.25

0.50

0.75

1.00

1.25

1.50

Overweight Obese Morbidly Obese

Ref: normal

Adjusted for sex, age, plan site, and plan type

* p<.05

**

*

*

**

*

Od

ds

Rat

io Exercise Smoking

Alcohol

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Strengths and Limitations

• Largest and most current database that has been used for this type of study

• HRA data

– Self-reported height, weight and health behaviors

– Survey instruments

• Claims data

– Unreported comorbidities and health care services

• Single BMI measurement, one year of claims data

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Conclusions

• Obese more likely to have comorbidity, be hospitalized, have higher health care costs, and engage in unhealthy behaviors

• Findings will help:

– Health plans better understand how obesity is affecting

their members' health and use of health care resources as

well as the impact of obesity on their costs

– Providers, health plans, and employers identify which

conditions to focus on for disease prevention and

management programs

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Acknowledgements• Johns Hopkins University – Jonathan Weiner, Jeanne

Clark, Hsien-Yen Chang, Tom Richards, Andrew Shore, Shari Bolen

• BCBS Association – John Newman, Greg Wozniak, Nadine Caputo, Mary Madison

• BCBS plans – BCBS of Tennessee, BCBS of Hawaii, BCBS of North Carolina, BCBS of Michigan, Independence Blue Cross, Highmark, Wellmark

• Funders – J&J Ethicon Endo-Surgery, Pfizer, GlaxoSmithKline