Visceral adipose tissue differences in black and white ...

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metabolic variables were studied in 8 black and. 10 white age- and weight-matched obese women undergoing a 6-mo weight-reducing regimen. Fat pat- terning.
Visceral adipose women1’ Joan

M

Conway,

Susan

ABSTRACT studied

tissue

Z Yanovski,

Fat distribution

8 black

in

women

undergoing

terning

was

and

a 6-mo

determined

by

Nib

and

10 white

weight-matched

weight-reducing

regimen.

using

anthropometry

total,

subcutaneous,

ipose

(VAT)

at the

L2-L3

spine,

women

had

the

during,

smaller

L2-L3

ences

before,

(P

depots 0.004)

=

persisted

after

an

was

similar

23%

VAT

than

white

less

(P

glycerides

lower 0.006)

=

density-lipoprotein study

bolic

risk

1995;61

L4-L5

(P

that

factors

sites.

(P

0.007).

=

Black

(P < 0.001). exist

for obesity-related

illness.

who

in

posity,

computed

body

tomography,

sition

than

do white

children

this meta-

Am J Clin

Nutr

regional

adi-

ethnicity

particularly

hypertension,

tance

(1-4).

The

performed

in

studies

have

dominal

are

Black 50%

are

kg/m2] of black

of severe

complications VAT depot, Differences

Am

J Clin

comes

from

the

effect by

race

on

of

obesity

composition for in

is an increased

1995;61:765-71.

these

little

with metabolic

observed surrogates,

in

Printed

more

deposits

trends

fatness,

these

in

fat

socioecodistribution, in

black,

differences

central

of VAT

as might

patterns

of obesity

and

are

therefore

more

associated with and Pi-Sunyer

obese black women (as defined had less insulin resistance, less serum They

of total than white

in their

I

medical

From

vice,

triglycerides concluded

by glu-

than did upperthat upper-body

body fatness, is less detrimental women. Actual VAT was not

study.

the US Department

Beltsville

Human

Laboratory, of Diabetes,

[body

mass

index

ical

whether the to the greater

excess preva-

to the size of the to obesity. and

white

(12).

The

between

fat-free American

Radiology, 2

mass Society

The

800

Center,

Institute

and

Institutes

used

Agricultural

Research

and the National Digestive

National

Optifast

of Agriculture,

Nutrition

Kidney was

Research

Ser-

Human

Per-

and

of Mental

Diseases,

of Health,

in the study

Diet

Health,

National

Department

Bethesda,

of Clin-

MD.

a gift of Sandoz

Nutrition

Corp

(Minneapolis). 3

of obesity-related

© 1995

ethnic of

differ-

evident in the into adulthood.

patterns

The

of fat depo-

factors. exceeding

composition

in USA.

are

metabolic aberrations of VAT. However, Dowling

obesity, independent for black women

Institute

of the

be-

in body-fat

intolerance, and lower obese white women.

formance

black

density

large

and

decades

this

in childhood,

fat distribution

the

or how

704),

Apparently,

differences

(19) found that upper-body waist-hip ratios) actually

measured

that

recently =

women, as measured by anthropometnic that they may be more likely than white

to demonstrate larger depots

cose body

(n

VAT-deposition

variables.

to have

The

independent

women,

black suggest

likely

four

body

white

women

pattern

children adolescence

reported

about

more

between

(18).

were

is known

mellitus

risk

almost

further

patterns

are also

obese

to an increased

noted

abwomen,

obesity-related they

severely

difference

whites

Nutr

been

white

diabetes

However,

studies

between in

of

resis-

numerous

association

(1 1). It is not known women is secondary

in body have

and

be

insulin

aberrations

affected

obesity,

documented

blacks

to

and

at a similar degree of obesity, or to some other factors unrelated

populations best

an

adipose tissue and mortality,

Although

a prevalence

(10).

women 32

(5-8).

non-insulin-dependent

disease

white

lence

on have

particularly as

evidence

shown

data

such

the

metabolic

who

cardiovascular (BMI)> morbidity

of

populations

and

limited

conditions

than

bulk

consistently

women, (9),

hyperlipidemia,

white

obesity

there

that increased visceral with greater morbidity

central

thickness was

(17).

mass

and Conupper-body

This

begins

a more

nomic status, and age. Despite these apparent

likely these

Introduction

study

ences between black and white preschool period and through (18)

black

patterns

skeletal

Zillikens greater

50).

of

CARDLA

have

women

It is well established (VAT) is associated

in the

children

Mueller

denser

skinfold

(n

population

black

and

composition,

a large

cause

deposition

and

subscapular whites

of fat-deposition

affect Obesity,

increased with

are described

compared

WORDS

an

Differ-

:765-71.

KEY

on

as compared

centrality

from

VAT

44)

of a heavier

mass (12-15). In 1990, that black women have

at both

women

Data

in

because

based

confirmed

(P 0.031) and tnhigher plasma high-

differences

in blacks denser muscle (16) suggested

the

weight loss. Although groups, black women had

women

and way (n

Black

women

(FFM)

adof

fast.

0.054)

-

plasma glucose with significantly

racial

levels

S Hubbard

obesity

visceral

L4-L5

white

pat-

17.2-kg

in both

concentrations

suggest

Fat computed

a modified

than

average

ratio

after

of VAT and

waist-hip

had significantly

and

and

were obese

and

and

Van

in black and white

Mention

guarantee imply 4

of a trade or warranty

approval Address

Building

or proprietary US

to the exclusion reprint

308,

mark by the

requests

Room

101,

of other to IM

10300

product

Department

products

Conway,

Baltimore

does

of Agriculture that

may

not

constitute and

does

a not

be suitable.

USDA/ARS/BHNRC/DHPL, Avenue,

Beltsville,

MD

20705-

2350. Received

June

Accepted

for

for Clinical

21,

1994.

publication

Nutrition

October

7, 1994.

765

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lumbar

and

variables

and

to quantitate areas

A Avila,

metabolic

age-

tomography tissue

differences

766

CONWAY The

present

study

was

conducted

to determine

whether

white women, and variables in obese

age-

during,

and

weight-matched

women

very-low-energy-diet

before,

and

after

AL

kJ/d

dif-

ferences exist in VAT between black and how these differences might affect metabolic

El

(800

period gradually a

program.

wk

kcal/d)

consumed

(refeeding) increased

they

were

in

lasted their

five

consuming

a balanced

5024-6276 kJ/d (1200-1500 living during all periods

and

Subjects

dietary exercise

Twenty

obese

women,

weight-loss

parents Similarly, One

and

woman

were

born

to have

was

in

VAT

white

All

grandparents all black women

black

den

9 black

study.

born

measured

woman

was

white

in the West States.

by

unable

participated

women

Indies

Two

computed

in

had

and

white

were

CT

5 of

the

last

Body

week

to

abdominal

made

degree

of

abdomen

activity,

but

required

to

determined

and only recruited

MD,

No

selections

by

body

overweight,

or physical

have a BMI weight loss. loss treatment

> 30 (kg/m2), because of the The subjects were participating study, designed to evaluate

type,

subjects

were

maximal

(thigh) (24). level of the

amount of expected in a 6-mo weightthe effects of binge

region was

height

was

Body isotope

composition dilution

and

tions

to calculate

with

measured

and

without

variables,

binge-eating

the

data

are

disorder

not

between

for

presented

any

of the

by binge-eating

status. Subjects were in general a diagnosis of hypertension subjects taking medication wk

before

beginning

good health. In particular, none or dyslipidemia at study entry. discontinued these medications

the

study.

No

subject

had

overt

had All 2

diabetes,

in

no

method

to report.

Detroit)

was

for

by

one white woman Program guidelines

time

point

during

abdominal dcx (CI)

and mid-thigh was calculated

risk,

low-density-lipoprotein

at

one

time

approved ical the

point

by the

Research US

and

during

the

National

and

the

Center in Bethesda, Research Center periods.

during (1200

which kcal/d).

metabolic

women

The

first

subjects Initial

measures

protocol

Clin-

Committee

of

Research

consent

was

Waist

was

Ser-

obtained

A CT was

NIH/NIMH

MD, and in Beltsville, period

the USDA/ARS MD. There

(baseline)

assessed

800;

Corp,

and

the

supine spine

for

this

period.

volunteers were diet (VLED)

Minneapolis)

containing

at the L2-L3

of 1 wk,

subcutaneous

kJ/d and During

provided (Optifast 3349

To

with

a stadiometer.

underwater impedance

weighing, analysis

between

lack

from

the

(% BF)

the

equa-

density

selected

by

hy-

as

the

BLA

from

equations

BIA of

two

methods. between

of validated body

we

fat

with the the total TAT

the body A density

but

excluded

calculated

(RJL,

Gray

et al

circumferences, as follows (27): [square

9800;

tissue in each

lumbar software

(SAT) with made

pixels ranging of attenuation nonfatty

soft

the

conicity

in-

Milwaukee)

was

placed

view of the transaxial

were

levels.

The

package each the

in the

lower lumbar sections were images currently

image VAT,

the area and the

calculated.

cross-sectional

was traced mask was

the

Electric, subject

the L4-L5

using

(wt/ht)]

General

a lateral scout One-centimeter and

and

root

Each

by

measurements, the from the minimal

CT scanner used. For adipose tissue (TAT),

adipose

that included all units. This range (fat)

was

circumference was calculated

by the HIGHLIGHT

measure

ery of cursor.

hip

(model

analyzed

available (cm2) of

to consume 5024 and anthropometnic during

were

(WHR)

all measurements.

position and was performed.

Human three

were

consisted

NIH

fat

using

X 0. 109

scanner

used

obtained at the

period the liquid-formula

Nutrition

high-

Intramural

Agriculture

were instructed CT scanning were

study Studies

informed

had

concentrations

of Health Human

the 12 wk of the second with a very-low-energy Sandoz

The

of Agriculture’s

vice (USDA/ARS) and written from all subjects. The research was conducted

dietary

white

study.

Institutes

Subpanel

Department

Clinical Nutrition

two

(LDL)-cholesterol

and

body

calculated

Program

study,

0. 1 cm

was kg and

(25), developed in a population of obese women. Zillikens and Conway (26) demonstrated that prediction equations developed from BIA data in white populations are applicable in a black

black and Education

the

0.01

women,

Percent

Education

one

to the nearest

difference

body black

and (WTR)

hypertension,

at

the minimal Weight

the

ratio

mild

nearest

therefore analyses.

estimated by and bioelectric

(15),

abdominal ratio

for

(ht),

(hip), mid-thigh

women

minimal waist-thigh

met the National Cholesterol (23) for high cholesterol at one

and

fat by any of the in bone density

population. The waist-hip

(22)

balance

percent

weighing

buttocks,

and

significant

as assessed by fasting blood glucose. During the 6-mo course of study two white women met National High Blood Pressure guidelines

during

height

hip

in percent body known differences

white

drostatic

the

(wt),

(waist),

statistical

to the

was

weight

women, all

was (2H2O),

black

subjects

were

and

period.

abdomen of

in several

measured

(21).

found

included

on an electronic

of women of the

were

aerobic during

we also measured the abdomen at the the umbilicus was displaced from the

used

There

differences

during

measures (baseline)

dietary

minimal

Although umbilicus,

(BIA).

significant

food

patterning

circumference

groups Because

no

program

subsequent

at the

eating on weight loss and were therefore selected by presence or absence of binge-eating disorder (20). Four black women and five white women met criteria for binge-eating disorder Because

own

of

free-

image,

the

peniph-

a region of interest (ROI) of the resulting body ROl

from values tissues,

-150 to -50 Hounsfield included adipose tissue air,

and

bone.

The

total

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Bethesda,

were

were

their

were

All subjects were assessed study and health status and

Experimental

of the

measures

circumferences

their data are presented. by advertisement in the

measurements, Subjects

too obese completed

period.

andfat

Anthropometnic

One

secondary

the

woman was 18 women

VLED

of each

third

diet

subjects

monitored. A low-intensity was initiated by the subjects

initiation

composition

to fit into all three

and one black The remaining

the

at the

The

unable

(CT).

scanning

week obtained

the remain-

subjects tomography

to tolerate

claustrophobia the CT scanner.

area.

1 1 white,

the

and were born in the United States. had black parents and grandparents.

United

the

and

of

were (walking)

The

consumed

Methods

the

meals.

energy-deficient

kcal/d).

the baseline and refeeding periods. weekly by a physician during the compliance program

equal

12 wk, during which the women energy intake, so that by the final 6

RACIAL TABLE

DIFFERENCES

of demographic

data

at study Black

entry’

All

women

White

Education

(y)

14.3

± 2.0

34.8

±

165.3

±

(y) (cm)

Weight

(kg)

109.5

Hip

(cm) (cm)

Weight

loss

Percent

body

2

and

1.7

38.6

± 6.3

demographic

± 6.0 ± 8.1

0.84

± 0.1

1 10.9

± 14.0

parisons

were

133.0

± 16.9

period

and race)

± 5.9

17.1

± 15.0

groups.

52.8 ± 6.9

51.5

± 5.4

differences

between

races

were

were

t tests

were

characteristics

± 10.5

significant

SDs

performed

made

by using

Significance

mean

± SD

as a determination

black

and

test means

white

for of

women,

% BF, waist, hip, and age. of VAT, SAT, and TAT calculated. All other com-

a three

set at P

where

(SAS

as the measure

computed

by two

of variance

was

except

PC-SAS

that included Bartlett’s used to compare the

between

analysis

with

calculated

including: wt, ht, WHR, WTR, BMI, Pearson product-moment correlations with anthropometric surrogates were

± 24.4

38.2

Unpaired variances

± 8.6

17.4

no

tendency

of variability. equality of

128.8 fat (%) were

±

102.9

Means

factorial

(ANOVA) 0.05.

=

(dietary

for unbalanced

Data

are presented

as

indicated.

by

t test.

Entry

P