Does waist circumference predict disease risk beyond metabolic risk factors and body mass
index?
Peter M. Janiszewski, Ian Janssen, and Robert RossSchool of Kinesiology and Health Studies
Queen’s University
Ontario
2007 Obesity Society Annual Scientific Meeting October 21st
Relationship Between BMI and the Risk of Death
Stevens et al., N Engl J Med 1998.
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6 45-54 yrs
55-64 yrs
65-74 yrs
75-84 yrs
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.645-54 yrs
55-64 yrs
65-74 yrs
75-84 yrs
Rel
ativ
e R
isk
Rel
ativ
e R
isk
Body Mass Index Body Mass Index
Women Men<1
9.019
.0-21
.922
.0-24
.925
.0-26
.927
.0-28
.929
.0-31
.9
<19.0
19.0-
21.9
22.0-
24.9
25.0-
26.9
27.0-
28.9
29.0-
31.9
Obesity: A heterogeneous condition
≠
Central ObesityCentral Obesity Peripheral ObesityPeripheral Obesity
Vague 1956, AJCN
Men <102 cm ( < 40 in) >102 cm ( > 40 in) BMI (kg/m2) Class Women < 88 cm ( < 35 in) > 88 cm ( > 35 in)
Overweight 25.0 - 29.9 Increased HighObesity 30.0 - 34.9 I High Very HighObesity 35.0 - 39.9 II Very High Very HighExtreme Obesity > 40 III Extremely High
Health Risk
NIH National Heart, Lung and Blood Institute, 1998, Obesity Research.
Characterizing Obesity Related Health Risk
BMI + WC = HEALTH RISK
Waist Circumference
0
0.5
1
1.5
2
2.5
3
RR
for C
VD
Low WCMid WC
High WC
Low Mid HighBMI
Rexrode et al. 1998, JAMA
0
2
4
6
8
10
12
14
16
RR
for D
iabe
tes
Low WCMid WC
High WC
Low Mid HighBMI
Wang et al. 2005, AJCN
Obesity: A heterogeneous condition
Waist Circumference and Cardiometabolic Risk: A Consensus Statement
• “…there is not yet a compelling body of evidence demonstrating that WC provides…sufficient incremental value in predicting diabetes, CVD, and mortality above and beyond that offered by BMI and commonly evaluated cardiometabolic risk factors…”
• “…WC should only be measured if it can provide additional information that influences patient management.”
The Obesity Society, the American Society for Nutrition, and the American Diabetes Association (2007)
Current Investigation• Objective:
– To determine whether WC predicts risk of diabetes and CVD beyond that explained by commonly evaluated cardiometabolic risk factors and BMI
• Research Design:– Subjects: Men and women from the 1999-2004 National Health and
Nutrition Surveys (NHANES)
– Analysis: Logistic regression to calculate the odds of diabetes and CVD according to sex-specific WC tertiles
– Cardiometabolic Risk Factors: blood pressure, triglycerides, LDL and HDL cholesterol, and fasting glucose levels
Results: Subject Characteristics
Variable Total (n = 5882)
Men(n = 3001)
Women(n = 2881)
Age, y 44.2 ± 0.5 43.3 ± 0.5 45.1 ± 0.5
Waist circumference, cm 95.3 ± 0.4 98.5 ± 0.4 92.1 ± 0.5
BMI, kg/m2 27.7 ± 0.1 27.6 ± 0.1 27.8 ± 0.2
Impaired fasting glucose, % 24.6 (1.1) 30.3 (1.4) 19.0 (1.1)
Diabetes, % 8.1 (0.5) 9.2 (0.7) 7.1 (0.5)
Cardiovascular disease, % 7.0 (0.5) 8.0 (0.7) 6.0 (0.6)
Hypertension, % 27.3 (0.9) 26.6 (1.2) 28.1 (1.0)
High LDL-cholesterol, % 21.6 (0.8) 22.8 (0.9) 20.4 (0.1)
Low HDL-cholesterol, % 19.9 (0.8) 27.8 (1.0) 12.0 (0.9)
High triglycerides, % 14.7 (0.6) 17.0 (1.0) 12.4 (0.6)
Results: WC and Risk of Diabetes and CVDResults: WC and Risk of Diabetes and CVDO
dds
Rat
io fo
r Dia
bete
s
0
1
2
3
Odd
s R
atio
for C
VDLow Med High
Waist Circumference
Low Med High
Waist Circumference
0
1
2
3
4
5
6
7
8
Adjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smoking
Results: WC and Risk of Diabetes and CVDResults: WC and Risk of Diabetes and CVD
0
1
2
3
4
5
6
7
8
Odd
s R
atio
for D
iabe
tes
0
1
2
3
Odd
s R
atio
for C
VDLow Med High
Waist Circumference
Low Med High
Waist Circumference
Adjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smoking, metabolic risk factors and BMIAdjusted for sex, age, race, and smoking
Results: BMI and Risk of Diabetes and CVDResults: BMI and Risk of Diabetes and CVD
0
1
2
3
4
5
6
7
8
Odd
s R
atio
for D
iabe
tes
0
1
2
3
Odd
s R
atio
for C
VDLow Med High
BMI
Low Med High
BMI
Adjusted for sex, age, race, and smoking
Results: BMI and Risk of Diabetes and CVDResults: BMI and Risk of Diabetes and CVD
0
1
2
3
4
5
6
7
8
Odd
s R
atio
for D
iabe
tes
0
1
2
3
Odd
s R
atio
for C
VDLow Med High
BMI
Low Med High
BMI
Adjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smokingAdjusted for sex, age, race, and smoking, metabolic risk factors and WCAdjusted for sex, age, race, and smoking
Results: WC, Cardiometabolic Risk Factors and Diabetes Risk
02468
10121416
0 1 2 3+
Number of Cardiometabolic Risk Factors
Odd
s R
atio
for D
iabe
tes
Low WCModerate WC
High WC
Ptrend < 0.001 for both WC and risk factors
0
2
4
6
8
10
12
0 1 2 3+
Number of Cardiometabolic Risk Factors
Odd
s R
atio
for C
VD
Low WCModerate WC
High WC
Results: WC, Cardiometabolic Risk Factors and CVD Risk
Ptrend < 0.001 for risk factors, not significant for WC
0
2
4
6
8
10
12
0 1 2 3+
Number of Cardiometabolic Risk Factors
Odd
s R
atio
for C
VD
Low WCMod WC
High WC
Results: WC, Cardiometabolic Risk Factors and CVD Risk
Odd
s R
atio
for C
VD
Low Med HighWaist Circumference
0
1
2
3
Conclusions
• WC predicts risk of diabetes, but not CVD, beyond that explained by commonly obtained cardiometabolic risk factors and BMI
* p<0.05 vs Control
Effects of Aerobic Exercise (4 mo) With or Without Weight Loss on Waist Circumference in Obese Men and Women
Red
uctio
n in
Wai
st C
ircum
fere
nce
(cm
)
0
3
6
9
Obese Men
*
*
Control WeightLoss
No WeightLoss
Exercise
0
2
4
6
8
*
*
Obese Women
Control WeightLoss
No WeightLoss
Exercise
No Changein BMI
No Changein BMI
Ross et al. Ann Intern Med (2000) ; Ross et al. Obesity Research (2004)
Conclusions
• WC predicts risk of diabetes, but not CVD, beyond that explained by commonly acquired cardiometabolic risk factors and BMI
• Thus, WC should be a routine clinical measure for the identification and management of the high-risk, abdominally obese patient