Journal of Clinical Densitometry, vol. 6, no. 2, 75–85, 2003 Copyright 2003 by Humana Press Inc. All rights of any nature whatsoever reserved. 1094-6950/03/6:75–85/$20.00
Review Article Clinical Applications of Body Composition Measurements Using DXA Carlina V. Albanese,*,1 Evelyn Diessel,2 and Harry K. Genant2 1Osteoporosis and Bone Pathology Unit of Study, Institute of Radiology, University of Rome “La Sapienza,”Viale Regina Elena, 326, 00161 Rome, Italy; and 2Osteoporosis and Arthritis Research Group,University of California San Francisco, San Francisco CA 94143-0628, USAAbstract
Dual-energy X-ray absorptiometry (DXA) scanning was primarily developed for the diagnosis of osteo-
porosis and was initially applied to studies of the clinically important sites of the lumbar spine, femoral neck,and forearm. The rapid adoption of DXA has led to the development of different, competing generations ofequipment. Improvements have been achieved through advances in X-ray generation and detection technol-ogy, modification of data acquisition protocols, and implementation of more sophisticated image analysisalgorithms. As a result, DXA has been extended to allow the study of the total skeleton and its regional parts,as well as soft-tissue composition measurement. The three major components of the body: fat mass, lean mass,and bone mineral mass, can now be easily measured using a single whole body DXA scan with high precisionand low scanning time.
The comprehensive view of body composition provided by DXA makes it an attractive technique for a vari-
ety of clinical applications such as the prevention of cardiovascular and metabolic diseases, clinical manage-ment of different chronic diseases, and monitoring of the impact of treatment regimens on body tissues.
In this article we review the contribution DXA has made to the understanding of body composition in clin-
Key Words: Adults; body composition; clinical applications; review; whole body DXA. Introduction
osteoporosis, the prediction of fracture risk (1–2),and the monitoring of therapies (3). In addition to
BMD assessment, DXA devices are capable of mea-
devices were primarily developed for the diagnosis
suring body composition of the total body or body
of osteoporosis. Bone mineral density (BMD) mea-
surements in the proximal femur, the lumbar spine,
The main measurement technique is based on the
or the forearm provide a means for the diagnosis of
differential attenuation by bone, fat, and lean tissueof transmitted photons at two energy levels (4). The
Received September 26, 2002; Accepted January 29, 2003.
transmission at two energy levels allows the deriva-
*Address correspondence to Carlina V. Albanese, Osteo-
tion of two different components such as fat and lean
porosis and Bone Pathology Unit of Study, Institute of
mass in regions without bone. In regions with bone
Radiology, University of Rome “La Sapienza,” Viale Regina
the two components, bone and soft tissue, are mea-
Elena, 326, 00161 Rome, Italy. E-mail: carlina.albanese@uniroma1.it
sured, and the composition of the soft tissue needs to
DXA Devices for Body Composition and Total Body BMD Measurements
a Effective dose in brackets includes ovaries. b Patient doses according to the manufacturer.
be estimated with respect to the adjacent tissue val-
use of BMD measurements in osteoporosis. DXA
ues. Therefore, a body-composition scan of the total
body-composition measurements show a high corre-
body measures three compartments of the body: fat
lation with the abovementioned techniques (7–9),
and lean body mass, as well as total body bone min-
and are rapidly gaining interest and acceptance in
eral. Proteins, glycogen, mineral, and water (includ-
ing water and organic materials of the bone) are
This article provides an overview of the different
included in the component of lean tissue (5).
areas for which body-composition measurements
The DXA output provides information about the
with DXA have been instituted in clinical practice.
following masses (in grams): fat, lean tissue, and
Our research was based, in part, on a review of the
bone mineral content (BMC) of the total body and
current literature on body composition in adults.
body regions. The fat content is given in percentage. Additionally, regional and total body BMD (in
DXA Devices
A variety of alternative techniques for body com-
DXA technology has improved significantly in
position measurements are available and have been
the last few years, especially scanning times.
reviewed by Jensen (6). Anthropometry, for exam-
Whereas a few years ago a body-composition scan
ple, predicts fat content by measuring skinfold thick-
required more than 15 min, new DXA devices are
ness (ST) and body circumferences. Total body
capable of scanning the total body in less than 5 min.
water (TBW) can be measured by isotope dilution
Reduced scanning times are more convenient for
technique (injection or drinking of tritium or deu-
patients and technical staff and have contributed to
terium solution). A person’s average body density
increased acceptance of DXA measurements in body
can be estimated by underwater weighing. Total
composition research and clinical practice.
body potassium (TBK) counting predicts lean body
Table 1 lists current DXA devices that are
mass by measuring the naturally radioactive isotope
equipped with a body-composition mode. In addi-
potassium 40K. Other available techniques include
tion to these devices, older models such as the QDR
neutron activation analysis, bioelectrical impedance
1000 and QDR 2000 (Hologic Inc., Bedford, MA,
analysis (BIA), computed tomography (CT), mag-
USA), XR-26 (Norland Inc., Fort Atkinson, WI,
netic resonance imaging (MRI), and ultrasonogra-
USA) are still being used in clinical practice.
phy. Many of these techniques are restricted to a
For whole body scanning, it is imperative that all
small number of laboratories. In contrast, DXA
parts of the body (also arms and feet) are included in
devices are widely available owing to the widespread
the scan field for precise measurements. However,
Clinical Applications of Whole Body DXA
there are some limitations with respect to the size of
higher, and the technical staff should be appropri-
the imaging table and the X-ray dosage. For exam-
ately protected (15,16). An overview of the patients’
ple, patients taller than 1.82 m (6 ft) may not fit
radiation exposure using various DXA device is
entirely on the table. The accuracy of the measure-
given in Table 1. Considering the annual dose equiv-
ment is then slightly reduced. In very obese patients,
alent from natural background radiation (2400 µSv
e.g., over 135 kg (300 lb), the X-ray dosage may not
per annum), and from other imaging procedures
be sufficient for imaging the abdomen. Some devices
such as dental bitewing (60.0 µSv), chest X-ray
offer special modes for obese patients with increased
(50.0 µSv), and thoracic and lumbar lateral spine X-
ray (820.0 µSv), the radiation exposure from whole
To assess lean and fat mass composition, the
DXA systems use different calibration techniques.
In comparison to pencil-beam systems, fan-beam
The XR-26 and QDR systems rely on external cali-
geometry causes projection and magnification arti-
bration, using wedges made of aluminum and Lucite
facts. The projected area depends on the tissue
(polymethylmethacrylate) calibrated against stearic
height above the scanning table. The influence on
acid as 100% fat, and diluite saline solution as 100%
body-composition data is still under investigation;
lean tissue (10). The DPX systems use a plastic poly-
however, improved correction algorithms are being
oymethylen (Delrin) as 40% fat equivalent and water
implemented. The Prodigy, listed in Table 1, uses a
(~5% fat) as standard measurement (4). Therefore,
thin fan beam that requires multiple raster scans sim-
when comparing body-composition measurements
between various DXA devices, results of fat and lean
Quality control in bone densitometry is essential
tissue show high correlations but also systematic dif-
not only for clinical drug trials or epidemiological
ferences owing to different calibration (11). Tothill
studies in which multiple densitometers are
et al. (12) compared three DXA devices of different
involved, but also in routine clinical practice. To
manufacturers and found deviations in fat values of
ensure consistent performance, a quality-control
6% in the total body and up to 13% in the trunk.
scan with a known standard is carried out daily, and
Differences were also found when comparing two
the measurement is then compared with previous
distinct DXA models of the same manufacturer
scans in a quality-control database. The standard
used for these daily quality-control scans differs
Deviation in measurement results between the
with the manufacturer and may consist of anthropo-
devices can also be explained by the variations in the
morphic phantoms or geometric objects of known
technology. Differences exist in hardware (X-ray
voltage, higher and lower energy spectra using
Different standards for body-composition mea-
switching kilovolt or K-edge filters, different detec-
surements, such as the Variable Composition
tors) and in software (algorithms for edge detection,
Phantom (VCP), have been evaluated recently (18).
assumptions regarding distribution of soft tissue
DXA devices are proven to have long-term stabil-
above bone). Additionally, the imaging geometry
ity and provide high precision in BMD scans of
(pencil- and fan-beam) may cause deviation in mea-
1–2% and in body-composition scans of 2–6%
surement results. A pencil-beam (collimated by a
pinhole collimator) is coupled to a single detectorand scans the total body in a raster. In contrast, a fan-
Clinical Applications
beam (slit collimator) is coupled to a multidetectorlinear array. Fan-beam systems use only three (QDR
Precise and accurate measurements of body com-
4500) or four (Expert) parallel sweeps across the
position are useful in achieving a greater under-
patient for a complete total body scan. The advan-
standing of human energy metabolism in physiology
tage of these techniques is the improved scanning
and in different clinical conditions, and in evaluating
time of 3 or 4 min. Fan-beam systems have a higher
interventions. Many disease processes affect bone
X-ray flux, and thus image quality is also improved.
and soft tissue at the same time. Therefore, the com-
As a consequence, radiation doses for patients are
prehensive view of body composition provided by
Nutritional Disorders
Overview of the Main Field of Clinical Applications of
Total body DXA accurately estimates the body
composition and the composition of weight loss in
1. Nutritional disorders
obese subjects (19), as well as other clinical condi-
tions in both overweight (20–22) and obese (22–23)
subjects, and can be used for monitoring such a con-
dition during therapeutic interventions.
2. Gastrointestinal disorders
Hendel et al. investigated the relationships
between body composition by DXA, fat distribu-
tion, sex hormone, and other cardiovascular risk
factors in overweight postmenopausal women (19).
3. Hepatobiliary disorders
Androgenicity, cigarette smoking, and alcohol con-
sumption correlate independently and positively
4. Renal disorders
with a central fat distribution. Furthermore, athero-
genic levels of lipids and lipoproteins were inde-
pendently related to central fat distribution,
androgenicity, and low levels of estrogens. Carey et
5. Endocrinological disorders
al. investigated the relationship between abdominal
fat and insulin sensitivity by DXA in normal and
overweight women (21). In this study, abdominal
adiposity appeared to be a strong marker and may
6. Bone disorders
be a major determinant of insulin resistance in
women. Goodpaster et al. (22) studied obese and
overweight women and men, using DXA to evalu-
7. Pulmonary diseases
ate abdominal fat and CT to evaluate subcutaneous
abdominal fat. They concluded that subcutaneous
fat as a component of central adiposity is also an
8. Drugs and substances
important independent marker of insulin resistance
in obesity. A relationship between fat distribution,
glucose tolerance, and gallstone pathogenic factors
was also demonstrated in obesity with the direct
9. Other disorders
measurements of fat mass by DXA (23).
Nutrition plays an important role in skeletal min-
eralization. The nutrients known with certainty to be
important are calcium, vitamin D, protein, and calo-
ries. Therefore, any form of malnutrition may also
affect total skeleton mineralization.
It is well known that women with anorexia ner-
vosa develop osteoporosis (24). However, afterweight gain an increase in total body fat and leanmass as well as an increase in total BMC was
whole body DXA makes it an attractive technique
observed in these patients (25). Contrary to the
for a variety of clinical research and practice appli-
symptoms associated with undernutrition, patients
with anorexia tended to remain energetic and
Following is a discussion of DXA’s contribution
shown high activity levels. There are indications
to the understanding of body composition, including
that in such patients a high level of physical activ-
bone mineral measurements, in different fields of
ity may result in an increase of total bone mass
Clinical Applications of Whole Body DXAGastrointestinal Disorders
Two different patterns of tissue loss may be found
Malnutrition is a common presenting feature in
in cirrhotic patients: in women, lean tissue is main-
patients with active Crohn’s disease (27). Analysis
tained while fat stores are reduced, as in early star-
of body composition is important in states of acute
vation; in men, lean tissue is reduced and body fat is
and chronic illness to quantify the magnitude of the
normal, as seen under conditions of stress (35). The
malnutrition. Such knowledge allows the clinician
reason for a gender difference in tissue loss in cir-
to assess the extent of nutritional depletion, which
rhotic patients could be related to the abundance of
in turn provides objective guidelines for the type
fat stores in females, which are progressively used to
and amount of required nutritional support. Patients
cope with the metabolic needs until muscle mass
with active Crohn’s disease have diminished total
remains the exclusive energy store (35).
body fat. Fat stores are the most severely affected,
Factors influencing muscle mass, such as nutri-
being 70% of normal value (27). It has been
tional depletion, altered protein turnover, and physi-
reported that DXA provides an accurate measure-
cal inactivity, may also, in part at least, negatively
ment of body fat, compared with other methods of
study, in malnourished subjects with Crohn’s dis-
Finally, in a study of hepathobiliary disorders by
DXA a significant association was reported between
Malabsorption in patients with celiac disease
increases of abdominal fat mass and gallstone devel-
may lead to alteration of nutritional state and cal-
cium balance. It is well-known that a gluten-free
Renal Disorders
diet may eliminate subjective symptoms and steat-
A number of factors may lead to malnutrition in
orrhea, but does not restore normal body composi-
patients with chronic renal failure. Malnutrition is a
tion. In fact, untreated patients show lower body
major factor in the greatly increased morbidity and
weight, fat mass, lean tissue mass, and BMD at the
mortality that occurs in these patients (36).
lumbar spine and total skeleton measured by DXA
It has been reported (37) that change in body
(29). After treatment, only lean mass seems to be
weight induced by hemodialysis has no influence on
whole body or regional BMC and fat tissue mass
Total gastrectomy is another condition known to
measurements by DXA. On the contrary, a change in
be complicated by both reduction of bone mineral-
the measurement of whole body lean-tissue mass is
ization (31) and nutritional disorders. However,
strongly correlated with change in body weight after
Liedman et al., using whole body DXA in a prospec-
hemodialysis. These findings agree with prior results
tive clinical study, reported a reduction of the body
of studies investigating the effect of hemodialysis on
fat, but they did not find an increased prevalence of
body composition by DXA and support the view that
osteoporosis in patients after total gastrectomy, even
DXA is a useful tool for estimating short-term
changes in body composition, such as those induced
Hepatobiliary Disorders
In patients undergoing renal transplantation, rapid
Malnutrition frequently occurs in patients with
changes in body composition occur, with variations
liver disease and may represent a risk factor influ-
in fat distribution (40) and bone mineralization (41).
encing both their short- and long-term survival (33).
In such patients, the widespread use of corticos-
The potential role of DXA in the assessment of body
teroids for immunosuppression, together with the
composition in cirrhotic patients is of particular
negative input of surgery and immobilization, could
interest, not only because it can provide additional
be associated with nutritional deterioration, the
and more precise information on their nutritional sta-
potential for an increase of body fat, and loss of lean
tus, but also because the estimation of metabolically
active body compartments by means of body-com-position analysis is essential for physiological
Endocrinological Disorders
processes standardization, such as energy expendi-
Growth hormone (GH) is one of the main energy
metabolism and body-composition regulators (42).
GH deficiency in young adults causes a change in
Bone Disorders
body composition with increased fat mass and
There is a great need for a simple method to iden-
reduced lean mass (43). Toogood et al. reported that
tify persons at low risk of developing osteoporosis,
even in the elderly, in whom GH secretion is nor-
because bone densitometry is too expensive and
mally very low, the additional imposition of GH
time-consuming for general use in an unselected
deficiency owing to organic disease may cause
population. Such a method would allow low-risk
changes in body composition with significant bio-
individuals to be excluded from screening with
logical impact (44). GH replacement therapy in
BMD measurements and/or increase the years
hypopituitary adults may alter body composition
between follow-up bone mass measurements. Fat
through its well-known lipolytic, anabolic, and
mass is decreased in osteoporotic patients and may
anti-natriuretic actions. A short-term study has
have an important protective role on the skeleton
shown that GH replacement therapy tends to nor-
(50). It was reported that women weighing more
malize soft-tissue body composition (43). A long-
than 71 kg have a very low risk of being osteopenic
term study has demonstrated that the beneficial
compared to women weighing less than 64 kg.
effects of GH therapy on body composition, i.e., a
Therefore, weight could be used to exclude women
reduction in body fat and an increase in lean mass,
from a screening program for postmenopausal osteo-
are preserved for at least 4 yr in hypopituitary
porosis (51). In a large study designed to compare
adults (45). An increase of whole body BMC and
body composition and BMD in Chinese women with
BMD in hypopituitary patients with adult-onset GH
vertebral fracture, it was found that not only fat mass
deficiency after 2-yr treatment was also reported
but also lean mass, height, and BMD at all sites were
significantly lower in fractured patients than normal
In acromegaly, body composition is characteristi-
cally altered by an increase in lean mass and a cor-
Paget’s disease is characterized by an increase in
responding reduction in fat mass (42). Treatment
bone turnover, often at multiple skeletal sites that are
with the somatostatin analog, octreotide, reduces
more susceptible to deformity or fracture than nor-
hormonal effects on target tissue. Short-term
mal bone. Whole body DXA measurements allow
octreotide therapy reduces GH levels, leading to a
regions of interest to be defined, so that the BMD of
significant reduction in lean mass as assessed by
focal areas within the skeleton can be assessed. It
DXA (47). Acromegaly may induce abnormalities in
was reported (53) that pagetic bone is more dense
bone metabolism. Kayath and colleagues (48)
than nonpagetic bone before treatment. With rise-
reported that osteopenia occurs in a minority of
dronate treatment, whole body BMC increases
patients with acromegaly and is predominant in the
because there has been an increase at pagetic and
spine. The authors did not find any correlation
nonpagetic sites. That the greatest increases in BMD
between duration of hypersomatotropism, GH/IGF-1
occur at trabecular sites affected with Paget’s disease
levels, and BMD, and they concluded that the major-
probably reflects, in part, the larger volume of the
ity of these patients have preserved BMD despite the
pre-treatment remodeling space in trabecular com-
Estimating body-composition changes is of inter-
The diagnosis of osteopetrosis is based on quali-
est in Cushing’s disease, which is characterized by
tative description of standard radiographs showing
redistribution of fat from peripheral to central parts
universal osteosclerosis. However, this technique
of the body owing to an excess of adrenocortical
does not permit the degree of osteosclerosis to be
steroids. Patients with this syndrome show reduced
measured. Whole body DXA was used to quantify
amounts of fat and lean-tissue masses in the arms
the osteosclerosis in the two subtypes of autosomal
and a slight reduction of total BMD and BMC com-
dominant osteopetrosis (54). In both types, BMC
pared with obese subjects and similar to nonobese
and BMD were markedly increased at the axial as
controls owing to depletion of selective protein
well as at the appendicular skeleton compared to
depots, as seen in hypercortisolism (49).
normals. Moreover, the authors have suggested that
Clinical Applications of Whole Body DXA
measurements of whole body BMC and BMD may
Drugs and Substances
be useful to complete the radiologic examination of
Glucocorticoids negatively affect bone mineral-
such patients, and in order to establish future thera-
ization, lipids, and glucose metabolism and can
peutic regimes, DXA might be helpful in monitoring
therefore modulate whole body composition. In
patients affected by giant cell arteritis, 2-yr treatmentwith high doses of prednisolone during the first 6 mo
Pulmonary Diseases
and lower doses thereafter resulted in a significant
The measurements of lean mass and fat mass
increase in total body fat as well as in trunk fat that
reserves in individuals with chronic obstructive pul-
remained after switching to a low-dose glucocorti-
monary disease (COPD) can aid in designing an
coid schedule (60). In female patients with systemic
adapted nutritional regimen, e.g., nutritional support
lupus erythematosus, the severity of disease and cor-
in malnutrition and food restriction in obesity,
ticosteroid exposure were independently associated
improving the clinical management of this condition
with a negative effect both on total body BMD and
(55). Body weight and lean mass abnormalities can
affect the health-related quality of life (HRQL) in
A number of hormones (62–65) have been shown
COPD patients. It was demonstrated that although
to modulate body composition measured by whole
body weight and lean mass abnormalities influence
body DXA. The menopause is associated with an
HRQL, their effects appear to be mediated through
increase in total body fat and decline in lean body
increased levels of dyspnoea in patients with sym-
mass. Oral estradiol/dydrogesterone and tibolone
tomatic obstructive lung disease (56). It was also
prevent total body fat changes, whereas transdermal
shown that respiratory muscle strength is closely
estradiol/oral dydrogesterone and tibolone prevent
associated with body weight and lean mass in
lean mass changes. Furthermore, oral estradiol/
patients with COPD. The comparison of respiratory
dydrogesterone prevents the shift to a central,
muscle strength with lean body mass should be use-
android fat distribution (62). Tamoxifene, an anti-
ful for studying the mechanism of respiratory mus-
estrogenic agent used in patients with advanced
cle weakness in patients with COPD (57).
breast cancer, may lead to an increase in fat content
In cystic fibrosis, the combination of pulmonary
in women who are undergoing this treatment (63).
dysfunction, which can increase energy require-
The administration of testosterone enanthate for 6
ments, and malabsorption, caused by pancreatic
mo as contraception in healthy men resulted in a
insufficiency and reduced bile-salt concentration,
modest reduction in fat mass and small increases in
make it difficult to provide adequate nutrition.
lean mass, muscle strength, and bone density (64).
Knowledge of body composition is important in
Exogenous androgens increase lean body mass and
states of acute and chronic illness where an individ-
modulate abdominal fat distribution in obese post-
ual may not be able to consume an adequate diet to
meet nutrition needs. Such a knowledge allows clin-
GH is a potent anabolic agent that tends to nor-
icians to provide nutrients needed for maintenance
malize body composition as shown in several studies
and repair (58). In addition, in cystic fibrosis, bone
on GH-deficient hypopituitary adults (43,45–46). In
mineral status may be impaired, although the patho-
addition, a low dose of biosynthetic GH can elevate
genesis of this bone mineral deficit is still uncertain.
insulin-like growth factor (IGF)-I levels in GH-defi-
The reduction of lumbar spine, femoral, and whole
cient adults and has a pronounced physical impact
body BMD observed in these patients suggests a
and a decline in fat mass, without the side effects
reduction in both cortical and trabecular BMD.
seen at higher dosage schedules (66).
Bachrach and colleagues have proposed that either
Total parenteral nutrition (TNP) may be subject to
osteopenia or osteoporosis be included as health
the inadequate provision of certain nutrients and the
risks for adults with cystic fibrosis and that bone
resulting nutritional complications may affect bone,
mineral status of such patients be assessed on a rou-
lean mass, and fat mass. However, it was reported
that patients receiving home TNP present a stable
body composition with no significant change in lean
ered in the design of future intervention studies for
mass, fat mass, or total BMC after a mean period of
20 mo. Individual changes in body weight and lean
Patients affected by reflex sympathetic dystrophy
mass were correlated with change in home par-
syndrome exhibited, before treatment, decreased
enteral nutrition energy supply (67).
lean and bone masses, and increased fat mass ascompared to the unaffected limb after 1-yr treatment. Other Diseases
In patients whose clinical manifestations had sub-
DXA has recently been used to study the body
sided, increased bone and lean masses were
composition of patients affected by diabetes (68),
acquired immunodeficiency syndrome (AIDS)
Whole body DXA analysis has been shown to
(69,70), and different neurological conditions such
reliably detect body-composition changes in amy-
as sympathetic dystrophy syndrome (71), amy-
otrophic lateral sclerosis (72) and can be used to pro-
otrophic lateral sclerosis (72), tetraplegy (73), and
vide a basis for appropriate nutritional advice
Patients with noninsulin-dependent diabetes
An increase in lean mass with a concomitant
mellitus (NIDDM) and those with insulin-depen-
decrease in fat mass was described in tetraplegic
dent diabetes mellitus (IDDM) may present an
patients after 8 wk of electrically stimulated leg
alteration of fat distribution that can result in pre-
mature cardiovascular risks (75). It was shown that
The patients, affected by Duchenne muscular dys-
abdominal adiposity seems to be a strong marker
trophy, exhibit total bone osteopenia and elevated
and may be a major determinant of insulin resis-
body fat, owing not to obesity, but probably to fatty
tance in overweight women (23) and that fat distri-
infiltration of skeletal muscles, known to occur in
bution becomes more abdominal with age and with
this disease. A significant correlation between mus-
menopause (76,77). In a controlled study (68), it
cle function and the percentage of regional variation
was reported that patients with IDDM have signifi-
of lean mass was also demonstrated (74).
cantly less total body and abdominal fat than thoseaffected by NIDDM, irrespective of age andmenopausal status. In postmenopausal patients
Conclusions
with IDDM, total body fat and abdominal fat werelower than those found in normal subjects, whereas
these were higher in premenopausal patients with
rapid, noninvasive bone measurements and body-
NIDDM as compared to normal subjects.
composition estimates with low radiation exposure
AIDS is characterized by progressive weight
for many clinical applications. Regional and total
loss and severe inanition. It was demonstrated that
body DXA have been of growing interest in differ-
women lose significant lean body mass in the late
ent fields of medicine because it offers an interest-
stages of wasting. However, in contrast to men,
ing alternative to other time-honored reference
women exhibit a progressive and disproportionate
methods mainly used by nutrition specialists. DXA
decrease in fat mass relative to lean mass at all
is simple to perform, less dependent on operator
stages of wasting, consistent with gender-specific
skills and experience, highly reproducible, and
effects in body composition in AIDS wasting (69).
A longitudinal study on changes in body composi-
In the clinical management of patients affected by
tion in AIDS showed a reasonable agreement
different chronic diseases, whole body DXA may
among DXA, TBW, BIA, and ST (70). The authors
provide further information about the natural history
demonstrate that weight loss is composed of a large
of the disease, and more importantly, may offer a
proportion of lean mass compatible with undernu-
noninvasive method for determining appropriate
trition and do not support the hypothesis of exces-
nutritional support during disease progression. It can
sive lean mass catabolism in such a disease,
also be used to evaluate and monitor the response to
suggesting that this information should be consid-
Clinical Applications of Whole Body DXAAcknowledgments
14. Abrahamsen B, Gram J, Hansen TB, Beck-Nielsen H. 1995
Cross Calibration of QDR 2000 and QDR 1000 Dual-
energy X-ray densitometers for bone mineral and soft-tissue
Breazeale and Carla Belloni for preparing the manu-
measurements. Bone 16 (3): 385–390.
15. Blake GM, Patel R, Lewis MK, et al. 1996 New generation
dual X-ray absorptiometry scanners increase dose topatients and staff. J Bone Miner Res 11(Suppl 1):S157. References
16. Steel SA, Baker AJ, Saunderson JR. 1998 An assessment of
the radiation dose to patients and staff from a Lunar Expert-
1. Cummings SR, Black DM, Nevitt MC, et al. 1993 Bone
XL fan beam densitometer. Physiol Meas 19:17–26.
density at various sites for prediction of hip fractures. The
17. Spector E, LeBlanc A, Shackelford L. 1995 Hologic QDR
Study of Osteoporosis Fractures Research Group. Lancet
2000 Whole-body scans: a comparison of three combina-
tions of scan modes and analysis software. Osteoporosis Int
2. Ross P, Huang C, Davis J, et al. 1995 Predicting vertebral
deformity using bone densitometry at various skeletal sites
18. Diessel E, Fuerst T, Njeh CF, et al. 2000 Evaluation of a new
and calcaneus ultrasound. Bone 16:325–332.
body composition phantom for quality control and cross-
3. Orwell ES, Oviatt SK. 1991 Longitudinal precision of dual-
calibration of DXA devices. J Appl Physiol 89:599–605.
energy x-ray absorptiometry in a multicenter study. J Bone
19. Hendel HW, Gotfredsen A, Andersen I, Hojgaard L, Hilsted
J. 1996 Body composition during weight loss in obese
4. Mazess RB, Barden HS, Bisek JP, Hanson J. 1990 Dual-
patients estimated by dual energy X-ray absorptiometry and
energy x-ray absorptiometry for total-body and regional
by total body potassium. Int J Obes Relat Metab Disord
bone-mineral and soft-tissue composition. Am J Clin Nutr
5. Pietrobelli A, Formica C, Wang Z, Heymsfield SB. 1996
Relationships and independence of body composition, sex
Dual-energy x-ray absorptiometry body composition model:
hormones, fat distribution and other cardiovascular risk fac-
review of physical concepts. Am J Physiol 34:941–951.
tors in overweight postmenopausal women. Int J Obes Relat
6. Jensen MD. 1992 Research techniques for body composi-
tion assessment. Perspectives in practice. J Am Diet Assoc
21. Carey DG, Jenkins AB, Campbell LV, Freund J, Chisholm
DJ. 1996 Abdominal fat and insulin resistance in normal
7. Heymsfield SB, Wang J, Heshka S, kehayias JJ, Pierson RN
and overweight women: direct measurements reveal a
Jr. 1989 Dual-photon absorptiometry: comparison of bone
strong relationship in subjects at both low and high risk of
mineral and soft tissue mass measurements in vivo with
established methods. Am J Clin Nutr 49:1283–1289.
22. Goodpaster BH, Thaete FL, Simoneau JA, Kelley DE. 1997
8. Tothill P, Han TS, Avenell A, McNeill G, Reid DM. 1996
Subcutaneous abdominal fat and thigh muscle composition
Comparisons between fat measurements by dual-energy X-
predict insulin sensitivity independently of visceral fat.
ray absorptiometry, underwater weighing and magnetic res-
onance imaging in healthy women. Eur J Clin Nutr
23. Hendel HW, Hojgaard L, Andersen T, et al. 1998 Fasting
gall bladder volume and lithogenicity in relation to glucose
9. Heymsfield SB, Lichtman S, Baumgartner RN, et al. 1990
tolerance, total and intra-abdominal fat masses in obese
Body composition of humans: comparison of two improved
non-diabetic subjects. Int J Obes 22:294–302.
four-compartment models that differ in expense, technical
24. Seeman E, Szmukler GI, Formica C, Tsalamandris C,
complexity and radiation exposure. Am J Clin Nutr
Mestrovic R. 1992 Osteoporosis in anorexia nervosa: the
influence of peak bone density, bone loss, oral contraceptive
10. Goodsitt MM. 1992 Evaluation of a new set of calibration
use, and exercise. J Bone Miner Res 7(12):1467–1474.
standards for the measurement of fat content via DPA and
25. Orphanidou CI, McCargar LJ, Birmingham CL, Belzberg
AS. 1997 Changes in body composition and fat distribution
11. Modlesky CM, Lewis RD, Yetman KA, et al. 1996
after short-term weight gain in patients with anorexia ner-
Comparison of body composition and bone mineral mea-
vosa. Am J Clin Nutr 65:1034–1041.
surements from two DXA instruments in young men. Am J
26. Lichtenbelt WD van Marken, Heidendal GAK, Westerterp
KR. 1997 Energy expenditure and physical activity in rela-
12. Tothill P, Avenell A, Love J, Reid DM. 1994 Comparison
tion to bone mineral density in women with anorexia ner-
between Hologic, Lunar, and Norland dual-energy X-ray
absorptiometers and others techniques used for whole-body
27. Royall D, Greenberg GR, Allard JP, Baker JP, Knursheed
soft tissue measurements. Eur J Clin Nutr 48:781–794.
NJ. 1995 Total enteral nutrition support improves body
13. Ellis KJ, Shypailo RJ. 1998 Bone mineral and body compo-
composition of patients with active Crohn’s disease. JPEN
sition measurements: cross-calibration of pencil-beam and
fan-beam dual-energy X-ray absorptiometers. J Bone Miner
28. Royall D, Greenberg GR, AlIard JP, Baker JP, Harrison JE,
Knursheed NJ. 1994 Critical assessment of body composi-
tion measurements in malnourished subjects with Crohn’s
44. Toogood AA, Adams JE, O’Neill PA, Shalet SM. 1996
disease: the role of bioelectric impedance analysis. Am J
Body composition in growth hormone deficient adults over
the age of 60 years. Clin Endocrinol Oxf 45(4):399–405.
29. Gonzalez D, Mazure R, Mautalen C, Vazquez H, Bai J. 1995
45. Al-Shoumer KAS, Page B, Thomas E, Murphy M, Beshyah
Body composition and bone mineral density in untreated
SA, Johnston G. 1996 Effects of four years’ treatment with
and treated patients with celiac disease. Bone
biosynthetic human growth hormone (GH) on body compo-
sition in GH-deficient hypopituitary adults. Eur J
30. Mazure RM, Vazquez H, Gonzalez D, et al. 1996 Early
changes of body composition in asymptomatic celiac dis-
46. Johannsson G, Rosen T, Bosaeus I, Sjöström, Bengtsson
ease patients. Am J Gastroenterol 9(4):726–730.
BA. 1996 Two years of growth hormone (GH) treatment
31. Mellstrom D, Johaansson C, Johnell O, et al. 1993
increases bone mineral content and density in hypopituitary
Osteoporosis, metabolic aperations and increased risk for
patients with adult-onset GH deficiency. J Clin Endocrinol
vertebral fractures after partial gastrectomy. Calcif Tissue
47. Hansen TB, Gram J, Bjerret P, Hagen C, Bollerslev J. 1994
32. Liedman B, Bosaeus I, Mellstrom D, Lundell L. 1997
Body composition in active acromegaly during treatment
Osteoporosis after total gastrectomy. Scand J Gastroenterol
with octreotide: a double-blind, placebo-controlled cross-
over study. Clin Endocrinol 41:323–329.
33. Italian Multicentre Cooperative Project on Nutrition in
48. Kayath MJ, Viera JG. 1997 Osteopenia occurs in a minor-
Liver Cirrhosis. 1994 Nutritional status in cirrhosis. J
ity of patients with acromegaly and is predominant in the
spine. Osteoporos Int. 7(3):226–230.
34. Madden AM, Morgan MY. 1997 The potential role of dual-
49. Wajchenberg BL, Bosco A, Marone MM, et al. 1995
energy x-ray absorptiometry in the assessment of body com-
Estimation of body fat and lean tissue distribution by dual
position in cirrhotic patients. Nutrition 13(1):40–45.
energy X-ray absorptiometry and abdominal body fat eval-
35. Riggio O, Andreoli A, Diana F, et al. 1997 Whole body and
uation by computed tomography in Cushing’s disease. J
regional body composition analysis by dual-energy X-ray
Clin Endocrinol Met 80(9):2791–2794.
absorptiometry in cirrhotic patients. Eur J Clin Nutr
50. Mautalen C, Bagur A, Vega E, Gonzalez D. 1996 Body
composition in normal and osteoporotic women. Medina B
36. Degoulet P, Legrain M, Roach I, et al. 1992 Mortality risk
factors in patients treated by chronic hemodialysis. Nephron
51. Michaelsson K, Bergstrom R, Mallmin H, Holmberg L,
Wolk A, Ljunghall S. 1996 Screening for osteopenia and
37. Georgiou E, Virvidakis K, Douskas G, et al. 1997 Body
osteoporosis: selection by body composition. Osteoporos
composition changes in chronic hemodialysis patients
before and after hemodialysis as assessed by dual-energy x-
52. Lau EMG, Chan HHL, Woo J, Sham A, Leung PC. 1996
ray absorptiometry. Metabolism 46(9):1059–1062.
Body composition and bone mineral density of chinese
38. Stenver DI, Gotfredsen A, Hilsted J, Nielsen B. 1995 Body
women with vertebral fracture. Bone 19(6):657–662.
composition in hemodialysis patients measured by dual-
53. Patel S, Pearson D, Bhallah A, Maslanka W, White DA,
energy X-ray absorptiometry. Am J Nephrol 15(2):105–110.
Hosking DJ. 1997 Changes in bone mineral density in
39. Formica C, Atkinson MG, Nyulasi I, McKay J, Heale W,
patients with Paget’s disease treated with risedronate. Ann
Seeman E. 1993 Body composition following hemodialy-
sis: studies using dual-energy X-ray absorptiometry and
54. Grodum E, Gram J, Brixen K, Bollerslev J. 1995 Autosomal
bioelectrical impendence analysis. Osteoporos Int
dominant osteopetrosis: bone mineral measurements of the
entire skeleton of adults in two different subtypes. Bone
40. Hart PD, Wilkie ME, Edwards A, Cunningham J. 1993 DuaI
energy X-ray absorptiometry versus skinfold measurements
55. Pichard C, Kyle UG, Janssens JP, et al. 1997 Body compo-
in the assessment of total body fat in renal transplant recip-
sition by X-ray absorptiometry and bioelectrical impen-
ients. Eur J Clin Nutr 47:347–352.
dance in chronic respiratory insufficiency patients. Nutrition
41. Kwan JTC, Almond MK, Evans K, Cunningham J. 1992
Changes in total body bone mineral content and regional
56. Shoup R, Dalsky G, Warner S, et al. 1997 Body composition
bone mineral density in renal patients following renal trans-
and health-related quality of life in patients with obstructive
plantation. Mineral Electrolyte Metab 18:166–188.
airways disease. Eur Respir J 10:1576–1580.
42. O’Sullivan AJ, Kelly JJ, Hoffman DM, Freund J, Ho KKY.
57. Nishimura Y, Tsutsumi M, Nakata H, Tsunenari T, Maeda
1994 Body composition and energy expenditure in
H, Yokoyama M. 1995 Relationship between respiratory
acromegaly. J Clin Endocrinol Metab 78(2):381–386.
muscle strength and lean body mass in men with COPD.
43. Sartorio A, Narici M, Conti A, Giambona S, Ortolani S,
Faglia G. 1997 Body composition analysis by dual energy
58. Newby MJ, Keim NL, Brown DL. 1990 Body composition
x-ray absorptiometry and anthropometry in adult with chid-
of adult cystic fibrosis patients and control subjects as deter-
hood-onset growth hormone (GH) deficiency before and
mine by densitometry, bioelectrical impendance, total-body
after six months of recombinant GH therapy. J Endocrinol
electrical conductivity, skinfold measurements, and deu-
terium oxide dilution. Am J Clin Nutr 52:209–213. Clinical Applications of Whole Body DXA
59. Bachrach LK, Loutit CW, Moss RB. 1994 Osteopenia in
and non-insulin-dependent diabetes mellitus patients.
adults with cystic fibrosis. Am J Med 96:27–34.
60. Nordborg E, Schaufelberger C, Bosaeus I. 1998 The effect
69. Grinspoon S, Corcoran C, Miller K, et al. 1997 Body com-
of glucocorticoids on fat and lean tissue masses in giant cell
position and endocrine function in women with acquired
arteritis. Scand J Rheumatol 27(2):106–111.
immunodeficiency syndrome wasting. J Clin Endocrinol
61. Kipen Y, Strauss BJ, Morand EF. 1998 Body composition in
systemic lupus erythematosus. Br J Rheumatol
70. Paton NI, Macallan DC, Jebb SA, et al. 1997 Longitudinal
changes in body composition measured with a variety of
62. Hanggi W, Lippuner K, Jaeger P, Birkhauser Mh, Horber
methods in patients with AIDS. J Acquir Immune Defic
FF. 1998 Differential impact of conventional oral or trans-
Syndr Hum Retrovirol Feb 1;14(2):119–127.
dermal hormone replacement therapy or tibolone on body
71. Laroche M, Redon-Dumolard A, Mazieres B, Bernard J.
composition in postmenopausal women. Clin Endocrinol
1997 An X-ray absorptiometry study of reflex sympathetic
dystrophy syndrome. Rev Rhum Engl Ed 64(2):106–111.
63. Ali PA, Al-Ghorabie FH, Evans CJ, El-Sharkawi AM,
72. Nau KL, Dick AR, Peters K, Schloerb PR. 1997 Relative
Hancock DA. 1998 Body composition measurements using
validity of clinical techniques for measuring the body com-
DXA and other techniques in tamoxifen-treated patients.
position of persons with amyotrophic lateral sclerosis. JNeurol Sci 152(Suppl, 1):S36–42.
73. Hjeltnes N, Aksnes AK, Birkeland KI, et al. 1997 Improved
64. Young NR, Baker HW, Liu G, Seeman E. 1993 Body com-
body composition after 8 wk of electrically stimulated leg
position and muscle strength in healthy men receiving
cycling in tetraplegic patients. Am J Physiol 273 (3 Pt
testosterone enanthate for contraception. J Clin Endocrinol
74. Genaro MA, Palmieri MD, Tulio E, et al. 1996 Assessment
65. Lovejoy JC, Bray GA, Bourgeois MO, et al. 1996
of whole body composition with dual energy X-ray absorp-
Exogenous androgens influence body composition and
tiometry in Duchenne muscular dystrophy: correlation of
regional body fat distribution in obese postmenopausal
lean body mass with muscle function. Muscle Nerve
women: a clinical research center study. J Clin Endocrinol
75. Lapidus L, Bengtsson C, Larsson B et al. 1984 Distribution
66. Orme SM, Sebastian SP, Oldroyd B, et al. 1992 Comparison
of adipose tissue and risk of cardiovascular disease and
of measures of body composition in a trial of low dose
death: a 12 year follow-up of participants in the population
growth hormone replacement therapy. Clin Endocrinol
study of women in Gothenburg, Sweden. Br Med J
67. Tjellesen L, Staun M, Nielsen PK. 1997 Body composition
76. Ley CJ, Lees B, Stevenson JC. 1992 Sex-and menopause-
changes measured by dual-energy X-ray absorptiometry in
associated changes in body-fat distribution. Am J Clin Nutr
patients receiving home parenteral nutrition. Scand
77. Wang Q, Hassanger C, Ravn P, et al. 1994 Total and regional
68. OL Svendsen, C Hassager. 1998 Body composition and fat
body-composition changes in early postmenopausal
distribution measured by dual-energy x-ray absorptiometry
women: age-related or menopause-related? Am J Clin Nutr
in premenopausal and postmenopausal insulin-dependent
25 Dorso - P1 M Serie n° 3 di 3 VANTIN GIOVANNI GENOVESE GIACOMO ROSSI ANDREA PREBIANCA MARIO MARCHESINI JACOPO Serie n° 2 di 3 CAPPELLARI ALESSANDRO BELTRAME OTTANI PIERCARLO FONTÒ GABRIELE LUNA PIETRO BOLOGNINO MASSIMO Serie n° 1 di 3 GUERRA LUDOVICO GUIOTTO RICCARDO MARCHESIN FILIPPO MARCHESIN GABRIELE GASTALDELLO ALESSANDRO 25 Dor
ETHNOPHARMACOLOGY AND TOXICOLOGY OF ANTIMALARIAL PLANTS USED TRADITIONALLY IN MSAMBWENI, KENYA. Dr. Joseph Mwanzia Nguta, BVM, MSc (University of Nairobi). Supervisors Department of Public Health, Pharmacology and Toxicology, University of Nairobi Professor Peter K. Gathumbi, BVM, MSc, PhD. Department of Veterinary Pathology, Microbiology and Parasitology, University of Nairobi. De