Clinical use of bone densitometry

In Vivo High-Resolution Bioimaging of Bone Marrow and Fracture Diagnosis Using Lanthanide Nanoprobes with 1525 nm Emission

Bones play vital roles in human health. Noninvasive visualization of the full extent of bones is highly demanded to evaluate many bone-related diseases. Herein, we report poly (acrylic acid) (PAA)-modified NaLuF₄:Yb/Er/Gd/Ce@NaYF₄ nanoparticles (PAA-Er) with second near-infrared emission beyond 1500 nm (also referred as NIR-IIb) for high-resolution bone/bone marrow imaging and bone fracture diagnosis. The NIR-IIb optical-guided bone marrow imaging presents a high signal to noise ratio, which is superior to that for imaging in the NIR-II window (1000-1400 nm, NIR-IIa). Importantly, we also investigated the size-dependent accumulation of the nanoparticles and the possible accumulation mechanism of the designed PAA-Er nanoprobes in bone marrow. Due to the high affinity capability of the PAA-Er nanoprobes, a highly sensitive NIR-IIb optical-guided bone fracture diagnosis was successfully achieved. This novel technology paves the way to design lanthanide nanoprobes for NIR-IIb optical-guided high-resolution bone marrow imaging and bone-related disease diagnosis.

In vivo live imaging of bone using shortwave infrared fluorescent quantum dots

Bone plays an increasingly critical role in human health and disease. More noninvasive multi-scale imaging techniques are urgently required for investigations on the substructures and biological functions of bones. Our results firstly revealed that SWIR QDs prepared by us acted as a bone-specific imaging contrast to achieve real-time observation of bone structures both in vivo and ex vivo. The major bone structures of both Balb/C nude mice and Balb/C mice including their skull, spine, pelvis, limbs, and sternum could be rapidly and gradually identified via blood circulation after QD injection in vivo. More importantly, the binding capability of our QDs mainly depended on the biological activities of bone tissues, suggesting that our technique is suitable for in vivo live imaging. In addition, the cell imaging results suggested that the potential mechanism of our bone imaging could be ascribed to the highly specific interaction between QDs and MC3T3-E1 cells. In a word, the skeletal structures and biological activities of bones are anticipated to be observed and monitored with this QD-guided SWIR imaging strategy, respectively. This radiation-free QD-guided SWIR live imaging of bone can add new insights into a comprehensive study of bones in vivo and provide a basis for early diagnosis of bone diseases.

Dual-energy X-ray absorptiometry is a reliable non-invasive technique for determining whole body composition of chickens

In this study, a Lunar Prodigy dual-energy X-ray absorptiometry (DEXA) scanner was validated as a technique to estimate chicken body composition in a non-invasive way. Former research has emphasized the importance of validation of every scanner and software version. In a first trial, DEXA estimated body composition for broilers was correlated with chemical carcass analysis to develop prediction equations. As such, those equations can be used in later experiments with chickens to correct DEXA estimations to estimate body composition accurately by DEXA. DEXA estimated fat mass, lean tissue mass, bone mineral content (BMC) and total body mass, which is the sum of fat, lean mass and BMC, were compared to chemically analyzed crude fat, lean mass as the sum of protein and water and body ash content and scale body weight, respectively. Those regression equations were then used in a second trial to determine body composition based upon DEXA for breeders at different ages. In this experiment, fat and lean tissue determined by DEXA, were compared to dissection parameters commonly used for assessing carcass quality, namely breast muscle and abdominal fat. The first trial showed that DEXA provides high correlations for body mass (ρ = 1) and the individual tissue masses separately (ρ ranging between 0.98 and 1). These high correlations allow for accurate prediction of those components with the developed regression equations. Proportional fat and lean tissue were correlated with their chemical counterparts, however, to a lower extent than absolute values due to lower variation between the proportional weights. BMC percentage was not significantly correlated with ash percentage. Furthermore, in trial 2 high correlations were observed between dissection parameters and DEXA-corrected estimations. These correlations show that DEXA can assess carcass quality in breeders without sacrificing the birds. In conclusion, DEXA is a reliable technique to estimate breeder and broiler body composition in a non-invasive way, hence allowing for longitudinal studies over longer periods of time while avoiding sacrificing of birds.

Predictive and modifying factors of bone mineral density decline in patients with COPD

RATIONALE

Various determinants of osteoporosis have been previously identified. However, only a few longitudinal studies have examined related factors. We aimed to investigate factors predicting and modifying rapid decline of bone mineral density in patients with chronic obstructive pulmonary disease.

METHODS

We analyzed patients with chronic obstructive pulmonary disease whose bone mineral density were measured at least three times over three years (n = 111). We divided annual per cent changes of bone mineral density in different body parts into tertiles. Rapid decliners (n = 33) were defined as those with the largest decline in at least two parts; all other participants were defined as non-rapid decliners (n = 78).

RESULTS

At enrollment, bone mineral density did not differ between the two groups. However, rapid decliners had a significantly greater rate of new vertebral fractures over 3 years compared with non-rapid decliners. On multivariate logistic regression analysis, age, moderate to severe emphysema, no daily exercise habits, and anemia increased the likelihood of rapid decliners. Furthermore, patients who newly started and continued bisphosphonate exhibited higher annual per cent changes of bone mineral density than did those without bisphosphonate use.

CONCLUSIONS

A rapid decline in bone mineral density correlates to a higher likelihood of vertebral fracture. We clarified the predictors of bone mineral density decline and demonstrated that bisphosphonate use might modify bone mineral density in patients with chronic obstructive pulmonary disease.

The epidemiology of osteoporosis in Italian postmenopausal women according to the National Bone Health Alliance (NBHA) diagnostic criteria: a multicenter cohort study

PURPOSE

The study was aimed at evaluating the prevalence of osteoporosis, defined by BMD and the National Bone Health Alliance (NBHA) criteria, and the prevalence of clinical risk factors for fractures in Italian postmenopausal women.

METHODS

This is a cross-sectional, multicenter, cohort study evaluating 3247 postmenopausal women aged ≥ 50 and older in different areas of Italy in the period 2012-2014. All the participants were evaluated as far as anthropometrics; questionnaires for FRAX^® and DeFRA calculation were administered and bone mineral density was measured at lumbar spine, femoral neck and total hip by DXA.

RESULTS

The prevalence of osteoporosis, as assessed by BMD and NBHA criteria was 36.6 and 57%, respectively. Mean ± SD values of FRAX^® and DeFRA were: 10.2 ± 7.3 and 11 ± 9.4 for major fractures, and 3.3 ± 4.9 and 3.9 ± 5.9 for hip fractures, respectively. Among clinical risk factors for fracture, the presence of previous fracture, particularly non-spine/non-hip fracture, parental history of hip fracture and current smoking were the most commonly observed.

CONCLUSIONS

Our study showed that more that the half of postmenopausal women aged 50 and older in Italy has osteoporosis on the basis of the NBHA criteria. There is a relevant high risk of femur fracture, as assessed by the FRAX^® and DeFRA and previous fracture, parental history of hip fracture and current smoking are the most common risk factors. The data should be considered particularly in relation to the need to increase prevention strategies on modifiable risk factors and therapeutic intervention.

Dual Photon Absorptiometry for Bone Mineral Measurements Using a Gamma Camera

A gamma camera was equipped with a special collimator and arm assembly for bone mineral measurements with dual photon absorptiometry (DPA). The system was evaluated in vitro and in vivo and compared both with a rectilinear DPA and a dual energy X-ray (DEXA) system. All 3 systems showed a linear response in measurements of 4 vials, containing different amounts of hydroxyapatite. Phantom measurements with the gamma camera system showed a precision of 1.6% to 2.8%. Results obtained in 8 healthy volunteers with rectilinear and gamma camera systems were well correlated (R2 = 0.78). With the photon beam directed from posterior to anterior, the separation of vertebrae was easy with the gamma camera system. We conclude that bone mineral measurements can be made with a gamma camera for assessment of fracture risk and in the decision process whether a patient needs treatment or not. For follow-up, the precision of DPA with a gamma camera is inadequate.

No evidence of circulating autoantibodies against osteoprotegerin in patients with celiac disease

AIM: To investigate risk factors for low bone mineral density (BMD) in celiac disease (CD) patients, focusing on circulating autoantibodies against osteoprotegerin (OPG).

METHODS: Seventy asymptomatic CD adult patients on gluten-free diet (GFD) and harbouring persistent negative CD-related serology were recruited. Conventional risk factors for osteoporosis (e.g., age, sex, menopausal status, history of fractures, smoke, and body mass index) were checked and BMD was assessed by dual energy X ray absorptiometry. Serum calcium and parathyroid hormone (PTH) levels were evaluated. Thirty-eight patients underwent repeat duodenal biopsy. Serum samples from a selected sub-group of 30 patients, who were also typed for human leukocyte antigen (HLA) DQ2 and DQ8 haplotype, were incubated with homodimeric recombinant human OPG and tested by western blotting with an anti-OPG antibody after immunoprecipitation.

RESULTS: Despite persistent negative CD-related serology and strict adherence to GFD, 49 out of the 70 (74%) patients displayed low BMD. Among these patients, 13 (24%) showed osteoporosis and 36 (76%) osteopenia. With the exception of age, conventional risk factors for osteoporosis did not differ between patients with normal and low BMD. Circulating serum calcium and PTH levels were normal in all patients. Duodenal mucosa healing was found in 31 (82%) out of 38 patients who underwent repeat duodenal biopsy with 20 (64%) still displaying low BMD. The remaining 7 patients had an incomplete normalization of duodenal mucosa with 6 (84%) showing low BMD. No evidence of circulating antibodies against OPG was found in the serum of 30 celiac patients who were tested for, independent of BMD, duodenal histology, and HLA status.

CONCLUSION: If any, the role of circulating autoantibodies against OPG in the pathogenesis of bone derangement in patients with CD is not a major one.

Bone Measurement, Physical Activity and the Aging Skeleton

De nombreuses recherches sur l'ostéoporose ont récemment été axées sur la prévention de la diminution de la densité osseuse à un âge avancé. Chercheurs et cliniciens peuvent maintenant mesurer avec précision les effets des thérapies et des traitements de prévention sur le squelette. L'activité physique régulière est donc suggérée comme étant l'une des mesures importantes au maintien de la densité osseuse et à la prévention de l'ostéoporose. Cet article passe en revue les techniques quantitatives permettant d'évaluer la densité osseuse et donne un aperçu des récentes enquêtes transversales et longitudinales reliées aux bienfaits possibles de l'activité physique sur le squelette vieillissant.

Bone density changes after radiation for extremity sarcomas: exploring the etiology of pathologic fractures

PURPOSE

The incidental irradiation (RT) of adjacent bone that takes place during treatment of soft tissue extremity sarcomas is generally presumed to "weaken" the bone by decreasing its density, which subsequently increases the risk for pathologic fracture. This investigation intended to assess the relative effects on bone density of both RT and diminished mechanical loading secondary to tumor-induced and therapy-induced functional extremity impairment.

METHODS AND MATERIALS

19 patients treated with surgical excision and RT for soft tissue extremity sarcomas had bone density measured using dual energy X-ray absorptiometry at four sites: the irradiated (A) and contralateral (B) bone, and an uninvolved bone (C) in the treated extremity and its contralateral counterpart (D). Analysis included (1) [A-B], (2) [C-D], (3) [(A-B), - (C-D)], and (4) [(A-B)/B - (C-D)/D].

RESULTS

The mean bone density for all irradiated sites was increased 0.08 ± 0.22 g/cm(2) (variance) compared to the contralateral unirradiated side when corrected for weight-bearing effects (3). An average increase in bone density of 9 ± 22% (p = 0.08) was also seen when the differences were divided by individual control densities to normalize variation in density of different anatomic sites (4).

CONCLUSIONS

RT does not routinely decrease bone density when corrected for weight bearing or mechanical effects. The pathogenesis for the known increased risk of pathologic fracture in irradiated bones is likely multifactorial, including possible alterations in bone remodeling that can result in stable, or even increased, bone density. Further clinical and basic studies are needed to confirm our unexpected findings.

Could lower bone turnover be a cause of chest pain during childhood?

Chest pain, a frequent complaint during childhood, rarely originates from a cardiac pathology. Although it usually is idiopathic, it also could be associated with psychogenic, musculoskeletal, respiratory, and digestive disorders. This study aimed to investigate a possible relation between bone mineral density and chest pain in children. Bone mineral density and bone metabolism parameters were measured for 50 children with chest pain, and the findings were compared with those for 40 age- and sex-matched healthy children. Most of the cases (64%) were in the idiopathic group, and musculoskeletal chest pain was the second most frequent complaint (12%). Although bone mineral densities and osteocalcin levels did not differ significantly between the whole chest pain group and the control group, both were found to be lower in the musculoskeletal chest pain group than in other groups and the control group (p < 0.05). Musculoskeletal chest pain may be related to reduced bone mineral metabolism, and monitoring of risk factors is of particular importance.

Underestimation of bone loss of the spine with posterior-anterior dual-energy X-ray absorptiometry in patients with spinal cord injury

BACKGROUND

Bone mineral density (BMD) of the lumbar spine (L-spine) has been reported to be normal by routine posterior-anterior (PA) bone density imaging in patients with chronic spinal cord injury (SCI).

OBJECTIVE

To determine BMD of the L-spine by PA and lateral (LAT) dual-energy radiographic absorptiometry (DXA) in patients with chronic SCI.

DESIGN

Prospective study.

SETTING

Veterans Affairs Medical Center and a private rehabilitation facility.

METHODS

Measurements of the PA and LAT L-spine and hip were performed in 15 patients with SCI: 9 with tetraplegia and 6 with paraplegia. The DXA (GE Lunar Advance DXA) images were obtained using standard software. Results are reported as mean +/- SD.

RESULTS

The mean age was 35 +/- 15 years (range = 20-62 years), and the duration of injury was 57 +/- 74 months (range = 3-240 months). T- and Z-scores were lower for the LAT L-spine than those for PA L-spine (T-scores L2: -0.7 +/- 1.2 vs. 0.0 +/- 1.4, P < 0.01; L3: -0.9 +/- 1.6 vs. 0.3 +/- 1.3, P < 0.002; L2-L3: -0.8 +/- 1.3 vs. 0.2 1.3 vs. 0.2 +/- P < 0.001; Z-scores Z-0.3 +/- 1.1 vs. 0.2 +/- 1.2, P < 0.05; L3: -0.6 +/- 1.3 vs. 0.5 +/- 1.3, P < 0.01; L2-L3: -0.4 +/- 1.1 vs. 0.4 +/- 1.2, P < 0.005). The T- and Z-scores for the total hip (-1.1 +/- 1.0 and -1.0 +/- 1.0, respectively) and L2-L3 LAT L-spine demonstrated remarkable similarity, whereas the L2-L3 PA L-spine scores were not reduced. Bone mineral density of the LAT L-spine, but not the PA L-spine, was significantly reduced with increasing duration of injury.

CONCLUSIONS

Individuals with SCI may have bone loss of the L-spine that is evident on LAT DXA that may be misdiagnosed by PA DXA, underestimating the potential risk of fracture.

Bone mineral density reference range in Estonia: a comparison with the standard database (NHANES III)

Dual-energy X-ray absorptiometry (DXA) is accepted as a standard for diagnosing osteoporosis. Several databases are available for T-score calculation worldwide. Our aim was to compare hip bone mineral density (BMD) in young Estonian adults with the mean BMD in the National Health and Nutrition Examination Survey (NHANES) femur database and to compare the performance of these 2 databases. A population sample of 304 subjects was analyzed with a Lunar DPX-IQ DXA machine (GE Lunar Co., Madison, WI). Seventy-seven healthy young individuals were selected based on their age (25-39 yr). Their femur neck, trochanter, and total hip mean standardized BMD was compared with the corresponding data from the NHANES III database. Diagnostic agreement was assessed in a population sample of adults and in a clinical convenience sample from the densitometry unit. The BMD in the proximal femur in healthy young Estonian adults did not differ from the mean BMD in the NHANES subjects (p > 0.05). Differences in diagnosing osteoporosis and osteopenia are present if the Estonian reference database is used instead of the US standard database. Prospective studies with fracture data for assessing the predictive capability of these reference databases and the additional benefit of adding the FRAX (World Health Organization Collaborating Centre for Metabolic Bone Diseases, University of Sheffield, UK) tool to fracture prediction and osteoporosis diagnosis are needed in Estonia.

Dual-energy X-ray absorptiometry overestimates bone mineral density of the lumbar spine in persons with spinal cord injury

BACKGROUND

Bone mineral density (BMD) of the lumbar spine (L-spine) has been reported to be normal or increased in persons with chronic spinal cord injury (SCI).

OBJECTIVE

To determine BMD of the L-spine by dual-energy X-ray absorptiometry (DXA) and quantitative computerized tomography (qCT) in men with chronic SCI compared with able-bodied controls.

DESIGN

Cross-sectional, comparative study.

SETTING

Clinical research unit, Veterans Affairs Medical Center, Bronx, NY, USA and Kessler Institute of Rehabilitation, West Orange, NJ, USA.

METHODS

Measurements of the L-spine were made in 20 men with SCI and compared with 15 able-bodied controls. The DXA images were acquired on a GE Lunar DPX-IQ. The qCT images of the L-spine were acquired on a Picker Q series computerized tomographic scanner.

RESULTS

The mean ages for the SCI and control groups were 44+/-13 vs 42+/-9 years, and the duration of injury of the group with SCI was 14+/-11 years. There were no significant differences between the SCI and control groups for L-spine DXA BMD (1.391+/-0.210 vs 1.315+/-0.178 g/m(2)) or for L-spine DXA T-score (1.471+/-1.794 vs 0.782+/-1.481). L-spine qCT BMD was significantly lower in the SCI compared with the control group (1.296+/-0.416 vs 1.572+/-0.382 g/m(2), P=0.05); the T-score approached significance (-1.838+/-1.366 vs -0.963+/-1.227, P=0.059). Subjects with moderate degenerative joint disease (DJD) had significantly higher T-scores by DXA than those without or with mild DJD.

CONCLUSION

Individuals with SCI who have moderate to severe DJD may have bone loss of the L-spine that may be underestimated by DXA, reducing awareness of the risk of fracture.

Dual-energy X-ray absorptiometry diagnostic discordance between Z-scores and T-scores in young adults

Diagnostic criteria for postmenopausal osteoporosis using central dual-energy X-ray absorptiometry (DXA) T-scores have been widely accepted. The validity of these criteria for other populations, including premenopausal women and young men, has not been established. The International Society for Clinical Densitometry (ISCD) recommends using DXA Z-scores, not T-scores, for diagnosis in premenopausal women and men aged 20-49 yr, though studies supporting this position have not been published. We examined diagnostic agreement between DXA-generated T-scores and Z-scores in a cohort of men and women aged 20-49 yr, using 1994 World Health Organization and 2005 ISCD DXA criteria. Four thousand two hundred and seventy-five unique subjects were available for analysis. The agreement between DXA T-scores and Z-scores was moderate (Cohen's kappa: 0.53-0.75). The use of Z-scores resulted in significantly fewer (McNemar's p<0.001) subjects diagnosed with "osteopenia," "low bone mass for age," or "osteoporosis." Thirty-nine percent of Hologic (Hologic, Inc., Bedford, MA) subjects and 30% of Lunar (GE Lunar, GE Madison, WI) subjects diagnosed with "osteoporosis" by T-score were reclassified as either "normal" or "osteopenia" when their Z-score was used. Substitution of DXA Z-scores for T-scores results in significant diagnostic disagreement and significantly fewer persons being diagnosed with low bone mineral density.

The use of bone age for bone mineral density interpretation in a cohort of pediatric brain tumor patients

BACKGROUND

Skeletal bone accretion occurs throughout childhood. The integrity of this process can influence future adult bone health and the risk of osteoporosis. Although surveillance of children who are at risk of poor bone accretion is important, the most appropriate method to monitor childhood bone health has not been established. Previous investigators have proposed using bone age (BA) rather than chronological age (CA) when interpreting bone mineral density (BMD) values in children.

OBJECTIVE

To investigate the value of BA assessment for BMD measurement in a cohort of children at risk of poor accretion.

MATERIALS AND METHODS

A cohort of 163 children with brain tumors who completed both a BMD assessment (quantitative computed tomography, QCT) and who had a BA within a 6-month interval were identified. The difference in BMD Z-scores determined by CA and BA was determined. The impact of salient clinical features was assessed.

RESULTS

No significant difference between CA and BA Z-scores was detected in the overall cohort (P = 0.056). However, the scores in 18 children (all boys between the ages of 11 years and 15 years) were statistically determined to be outliers from the values in the rest of the cohort.

CONCLUSION

Interpretation of BMD with BA measurement might be appropriate and affect treatment decisions in peripubertal males.

Chronic kidney disease and bone fracture: a growing concern

Susceptibility to fracture is increased across the spectrum of chronic kidney disease (CKD). Moreover, fracture in patients with end-stage kidney disease (ESKD) results in significant excess mortality. The incidence and prevalence of CKD and ESKD are predicted to increase markedly over the coming decades in conjunction with the aging of the population. Given the high prevalence of both osteoporosis and CKD in older adults, it is of the utmost public health relevance to be able to assess fracture risk in this population. Dual-energy X-ray absorptiometry (DXA), which provides an areal measurement of bone mineral density (aBMD), is the clinical standard to predict fracture in individuals with postmenopausal or age-related osteoporosis. Unfortunately, DXA does not discriminate fracture status in patients with ESKD. This may be, in part, because excess parathyroid hormone (PTH) secretion may accompany declining kidney function. Chronic exposure to high PTH levels preferentially causes cortical bone loss, which may be partially offset by periosteal expansion. DXA can neither reliably detect changes in bone volume nor distinguish between trabecular and cortical bone. In addition, DXA measurements may be low, normal, or high in each of the major forms of renal osteodystrophy (ROD). Moreover, postmenopausal or age-related osteoporosis may also affect patients with CKD and ESKD. Currently, transiliac crest bone biopsy is the gold standard to diagnose ROD and osteoporosis in patients with significant kidney dysfunction. However, bone biopsy is an invasive procedure that requires time-consuming analyses. Therefore, there is great interest in developing non-invasive high-resolution imaging techniques that can improve fracture risk prediction for patients with CKD. In this paper, we review studies of fracture risk in the setting of ESKD and CKD, the pathophysiology of increased fracture risk in patients with kidney dysfunction, the utility of various imaging modalities in predicting fracture across the spectrum of CKD, and studies evaluating the use of bisphosphonates in patients with CKD.

DXA-generated Z-scores and T-scores may differ substantially and significantly in young adults

Central dual-energy X-ray absorptiometry (DXA) is the gold standard for non-invasive measurement of bone mineral density (BMD). Using this value and subject demographics, DXA software calculates T-scores and Z-scores. Professional society guidelines for the management of osteoporosis are based on T-scores and Z-scores, rather than on the actual BMD value. Although one expects T-scores and Z-scores to be very similar in young men and women for any given BMD measurement, little literature exists on this issue. Our clinical experience shows that some younger adult individuals (premenopausal women and men younger than 50 yr) have larger than expected difference between their DXA T-score and Z-score. This cross-sectional study evaluates the extent of this discordance between Z-scores and T-scores in a sample of 4275 men and women aged 20-49 yr. All subjects were scanned by central DXA using equipment manufactured by GE Lunar, GE, Madison, WI, or Hologic, Inc., Bedford, MA. Significant differences between Z-scores and T-scores were seen within individuals at the lumbar spine, total hip, femoral neck, and trochanter (p value<0.001) for both DXA systems. Although these differences were less than half a standard deviation (SD) in most instances, the magnitude of difference was substantial at times, being 1 or more SD in up to 11% of cases (range: -1.95 to +1.54 SD). The smallest differences were seen at the total hip and the largest differences were seen at the femoral neck for both technologies. This is in part because there is no single standard Z-score definition, resulting in different methods of calculation across, and even within, DXA manufacturers. Standardization of Z-score definition and method of calculation is indicated. DXA Z-scores should be interpreted with caution in men and women aged 20-50 yr.

Prevalence and etiology of low bone mineral density in juvenile systemic lupus erythematosus

OBJECTIVE

Studies of adults with systemic lupus erythematosus (SLE) have frequently demonstrated the presence of decreased bone mineral density (BMD). However, there have been few investigations in pediatric patients to date. This study was undertaken to determine the prevalence of low BMD in patients with juvenile SLE and to identify associated risk factors.

METHODS

We studied 64 consecutive patients with juvenile SLE in whom routine dual x-ray absorptiometry (DXA) scanning was performed. Lumbar spine osteopenia was defined as a BMD Z score of < -1 and > or = -2.5, and osteoporosis as a BMD Z score of < -2.5. Decreased hip BMD was defined as a value of < 80%. Data on disease activity, quality of life, disease-related damage, sex, ethnicity, body mass index, age at diagnosis, age at DXA, medication use and duration, clinical features, and puberty status were collected at the time of DXA.

RESULTS

Lumbar spine osteopenia was seen in 24 patients (37.5%) and osteoporosis in 13 (20.3%). Decreased hip BMD was present in 12 patients (18.8%). By univariate analysis, osteopenia was significantly correlated with age, disease duration, duration of corticosteroid use, cumulative corticosteroid dose, azathioprine use, cyclophosphamide use, lupus nephritis, and damage. Two additional variables, mycophenolate mofetil use and class III-IV nephritis, were associated with osteoporosis. Abnormal hip BMD was associated with disease duration, duration of corticosteroid use, and cumulative corticosteroid dose. By multivariate analysis, only disease duration remained in the model for osteoporosis and abnormal hip BMD, while cumulative corticosteroid dose was the variable associated with osteopenia.

CONCLUSION

These results indicate that osteopenia and osteoporosis are common in juvenile SLE and are associated more closely with increased disease duration than with cumulative corticosteroid dose.

Parathyroid hormone is elevated but bone markers and density are normal in young female subjects who consume inadequate dietary calcium

Dietary Ca and osteocalcin (OC), parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), insulin-like growth factor (IGF)-I and sex hormone binding globulin (SHBG) were assessed simultaneously to bone mineral density (BMD) in 200 adolescent girls (aged 11–15 years) and 100 young women (aged 20–23 years), selected from the lowest and highest end of the Ca intake distribution of a larger population sample. Ca intake was evaluated by food frequency questionnaires, BMD was measured by dual energy x-ray absorptiometry at ultradistal and proximal radius of non-dominant arm, bone age was estimated from x-rays of left hand and wrist according to. Surprisingly, mean Ca intakes were below the dietary reference intakes in the subgroups of girls and women with the highest measured Ca consumption. Postmenarcheal, but not premenarcheal girls showed radial densities as high as the women and in no group was BMD associated with Ca intake. In all adolescents serum PTH was negatively related to dietary Ca. In girls before menarche IGF-I was positively associated with bone age, while in the same subjects the negative relationship between SHBG and BMD pointed to the crucial role of bioavailable sex steroids on bone mass apposition in early puberty. OC levels decreased progressively with age, while serum 25-OH-D significantly increased after menarche. In conclusion, although in adolescents low Ca intake has not been shown to induce any immediate deleterious effect on radial density, the compensatory hypersecretion of PTH supports the need for an adequate Ca intake to achieve peak bone mass.

Osteopenia in X-linked hyper-IgM syndrome reveals a regulatory role for CD40 ligand in osteoclastogenesis

We report that osteopenia is a prominent and previously unappreciated clinical feature of patients with X-linked hyper-IgM syndrome, an inherited immune deficiency disorder caused by mutations in the gene encoding CD40 ligand (CD40L). We therefore conducted studies to determine the relationship between CD40L and osteoclastogenesis. Recognizing that activated T cells express surface receptor activator of NF-kappaB ligand (RANKL) and can induce osteoclast differentiation of myeloid cells expressing RANK, we assessed the capacity of wild-type T cells and CD40L(-/-) T cells to induce osteoclastogenesis in vitro. Relative to wild-type T cells, activated CD40L(-/-) T cells from both humans and mice promoted robust osteoclast differentiation of myeloid cells. Whereas activated CD40L(-/-) T cells had normal expression of RANKL, they were deficient in IFN-gamma production. In subsequent studies, we cultured activated CD40L(-/-) T cells in the presence of IFN-gamma, and we found that the osteoclastic capacity of CD40L(-/-) T cells could be greatly diminished. These results show that CD40L can influence RANKL signaling through T cell priming, and thus they demonstrate a regulatory role for CD40L in bone mineralization that is absent in patients with X-linked hyper-IgM syndrome.

Enhanced trabecular-bone calcium deposition in female rats with a high physiological dose of prolactin diminishes after ovariectomy

Although an increase in trabecular-bone calcium deposition has been shown to be regulated by prolactin during lactation, the physiological significance of prolactin in bone calcium metabolism in nonlactating rats remains unclear. This investigation sought to demonstrate the effects of endogenous prolactin and a high physiological dose of exogenous prolactin on bone turnover and bone calcium deposition in normal female rats, using the45Ca-labeling technique. Our results showed that suppression of endogenous prolactin with 6 mg/kg bromocriptine for 15 days significantly enhanced bone formation, but not bone resorption, in primarily trabecular sites, resulting in a significant increase in calcium deposition in the sternum and vertebrae, from –0.20 ± 0.07 to 0.40 ± 0.09 (p < 0.05) and –0.07 ± 0.11 to 0.34 ± 0.06 (p < 0.05) mmol Ca·(g dry mass)–1, respectively. Similarly, 2.5 mg/kg prolactin, a high physiological dose, increased sternal and vertebral calcium deposition, from –0.20 ± 0.07 to 0.24 ± 0.09 (p < 0.05) and –0.07 ± 0.11 to 0.25 ± 0.18 (p < 0.05) mmol Ca·(g dry mass)–1, respectively, by increasing bone formation more than bone resorption. However, as expected, prolactin had no effect on the tibia or femur, which are primarily cortical sites. Because several actions of prolactin have been known to be estradiol-dependent, we further investigated the dependence of prolactin action on 17β-estradiol. We found that 2.5 mg/kg prolactin did not increase sternal calcium deposition in ovariectomized rats. However, 10 µg/kg 17β-estradiol supplementation restored the action of prolactin. Ovariectomized rats given 17β-estradiol plus prolactin also manifested slightly but significantly higher sternal total calcium content than sham-operated rats, (4.58 ± 0.12 vs. 4.36 ± 0.11 mmol Ca·(g dry mass)–1(p < 0.05)). We concluded that a high physiological dose of prolactin promoted calcium deposition in primarily trabecular sites of nonlactating rats. This effect was diminished after ovariectomy. In addition, we showed that basal endogenous prolactin played a role in the maintenance of normal trabecular-bone turnover.

Gaucher disease and bone: laboratory and skeletal mineral density variations during a long period of enzyme replacement therapy

The usefulness of bone turnover markers in Gaucher disease is still unclear and their utility in monitoring the effects of enzyme replacement therapy (ERT) on bone metabolism has not yet been investigated exhaustively. Skeletal involvement seems to improve slowly during ERT, but only a few studies evaluating bone mineral density (BMD) changes during a long follow-up period have been reported. The aim of this study was to assess the efficacy of ERT on bone involvement in a group of 12 type I Gaucher disease (GD I) patients by monitoring biochemical indices of bone resorption/formation and BMD measured by dual energy x-ray absorptiometry (DEXA). Serum (calcium, phosphorus, bone alkaline phosphatase isoenzyme, carboxyterminal propeptide of type I procollagen (PICP), carboxyterminal telopeptide of type I collagen (ICTP), osteocalcin, intact parathyroid hormone) and urinary (calcium, phosphorus, hydroxyproline and free deoxypyridinoline) markers of bone metabolism and lumbar BMD were measured at baseline, after 6 and 12 months, and then every year for a mean ERT follow-up period of 4.5 years (range 4.4-6 years). Twelve healthy adult subjects matched for age and sex were tested as negative controls. A significant decrease of PICP was detected in the patient group at baseline (mean value 100.52 ng/ml vs 142.45 ng/ml, p = 0.017), while ICTP was remarkably higher: mean value 3.93 ng/ml vs 2.72 ng/ml, p = 0.004 (two-sided Student's t-test). No changes in bone formation indices were observed during the follow-up period, while urinary calcium excretion increased significantly from 0.065 to 0.191 mg/mg creatinine (p = 0.0014) (repeated measures ANOVA). A significant BMD improvement was also detected after an average ERT period of 4.5 years: Z-score increased from -0.81 to -0.56 (p = 0.005) (two-sided Student's t-test). These data evidenced the ineffectiveness of the biochemical markers used in monitoring ERT efficacy in GD I skeletal involvement, whereas DEXA was demonstrated to be a reliable method with which to follow up BMD improvement.

Bone mineral density in children with nocturnal enuresis

In enuretic children there is a significantly higher incidence of fine and gross motor clumsiness, delayed developmental milestones, slower and poor linear growth, and these patients are shorter than normal children. Skeletal maturation of enuretic children has been determined with bone age in only two studies before, but to our knowledge bone mineral content of enuretic children has not previously been determined by bone mineral density measurement. Bone mineral density was measured by the dual-energy x-ray absorptiometry method in children with nocturnal enuresis and compared with that of a control group to detect whether there were any delay in bone development and any decrease in bone mass. Thirty enuretic children were compared with a control group of 40 healthy children with respect to body height and weight measurements, daily calcium intake, serum calcium, phosphorus and ALP levels, chronological and bone ages, and bone mineral density measurements. Of the parameters compared, bone age was significantly retarded, and bone mineral density was significantly reduced in children with enuresis (8.3 +/- 1.9 vs 9.7 +/- 2.3 years; p = 0.01, and 0.5476 +/- 0.07 vs 0.6077 +/- 0.05 g/cm2; p = 0.001, respectively). Chronological ages demonstrated a significant correlation with the bone ages in both the study and control groups (r = 0.852, p < 0.001, and r = 0.844, p < 0.001, respectively). However, the mean chronological age was significantly greater than the mean bone age in the study group (p < 0.001), whereas the mean chronological age was not significantly different from the mean bone age in the control group (p = 0.514). To clarify the exact mechanism responsible for these manifestations of skeletal maturation retardation, the relationship between the maturational delay of the central nervous system connections or the effect of any perinatal insult and the retardation in skeletal maturation remains to be determined.

Assessing bone mineral density in vivo: dual energy X-ray absorptiometry

Dual-energy X-ray absorptiometry can be used as a noninvasive tool to monitor the skeletal integrity of live birds. A pDexa X-ray bone densitometer was used to determine bone mineral densities (BMD) of the left tibia together with the fibula and the humerus of live, unanesthetized birds. Densitometry effectively detected changes in bone integrity of live birds fed varying levels of dietary calcium. Hens consuming 1.8, 3.6, or 5.4% dietary calcium had BMD of 0.147, 0.157, and 0.176 g/cm2 (SEM = 0.005), respectively (linear effect, P < 0.001). Likewise, bone ash weight, breaking force, stress, modulus of elasticity, and eggshell traits also increased linearly in response to increased calcium in the diet (P < 0.05). Densitometric live scans for BMD were positively correlated (P < 0.001) with bone breaking force (r = 0.65) and bone ash (r = 0.77). We also monitored BMD in live Leghorn and broiler females during their life cycle. The tibial BMD of White Leghorns and broilers increased from 15 to 65 wk of age with the BMD of the broiler tibia increasing at a greater rate than that of the Leghorn tibia (line x age interaction, P < 0.0001). A precipitous drop in BMD occurred during an induced molt of Leghorns subjected to 10 d of feed withdrawal. Our long-term goal is to improve skeletal integrity in egg-type chickens by genetic selection for improved BMD. By crossing a broiler with an egg-laying line, an F2 resource population of birds has been developed to identify quantitative trait loci influencing BMD in chickens.

The use of densitometry to detect differences in bone mineral density and content of live White Leghorns fed varying levels of dietary calcium

Densitometry was investigated as a noninvasive tool to monitor skeletal integrity in live White Leghorns as an indicator for osteoporosis, a noninfectious disease resulting in mineral loss from the bone. The objectives of the experiment were 1) to assess the ability of densitometry to detect differences in bone integrity in live White Leghorns fed varying concentrations of dietary calcium and 2) to correlate densitometric scans with other bone test methods and production parameters that are sensitive to calcium concentrations in the diet. Hens were fed hypercalcemic (5.4%), control (3.6%), or hypocalcemic (1.8%) diets from 32 to 58 wk of age. A Norland densitometer was used to assess bone mineral density (BMD) and bone mineral content (BMC) of the left tibia and humerus in restrained, unanesthetized hens at 36, 46, and 56 wk of age (experiment 1) and at 38, 48, and 58 wk of age (experiment 2). Bones were excised from hens at 38, 48, and 58 wk of age for breaking strength measurements. Results from the densitometric scans showed that BMD and BMC of the humerus and tibia of live hens decreased linearly when hens consumed diets with decreasing concentrations of calcium (experiment 2). Similar trends in BMD and BMC were detected in experiment 1 at 36 wk of age using BW as a covariate. The results from the densitometric scans were comparable to those obtained from other bone tests commonly used. For example, bone breaking force, stress, and modulus of elasticity decreased linearly as hens consumed decreasing concentrations of calcium. Bone breaking force was correlated with BMD (r=0.65, P<0.001). We concluded that densitometry accurately measures differences in BMD and BMC in live birds fed varying concentrations of dietary calcium.

Bone mineral density in juvenile dermatomyositis: assessment using dual x-ray absorptiometry

OBJECTIVE

To determine the bone mineral density (BMD) status of our juvenile dermatomyositis (DM) population and to compare the frequency of osteopenia in patients with active disease requiring corticosteroids with that in patients with inactive disease who are not receiving corticosteroids.

METHODS

Medical charts of all children diagnosed as having juvenile DM at our institution between 1989 and 1999 were reviewed for demographic and clinical data, including disease activity and duration of corticosteroid therapy. BMD measurements of the lumbar spine (L1-L4) were performed using dual x-ray absorptiometry (DXA). Z scores were calculated from the BMD data for comparison with published normative data.

RESULTS

A total of 15 patients were assessed: 10 with active disease, and 5 with inactive disease who had not taken corticosteroids for an average of 6.0 years (range 3.4-8.1 years). Baseline BMD measurements demonstrated osteopenia or frank osteoporosis in the majority of patients, including 6 of the 10 patients with active disease and 4 of the 5 patients whose disease was in remission. Fourteen patients had serial BMD measurements. Persistent or worsening osteopenia was documented in all patients who had ongoing active disease, except for 3 patients who had been treated with bisphosphonates because of vertebral compression fractures.

CONCLUSION

Osteopenia is common in patients with juvenile DM, and it usually worsens with ongoing disease. It can persist for many years after the disease enters remission. Bisphosphonates appeared to beneficially affect bone mineralization in our patients. Treatment to prevent the long-term complications of osteoporosis in patients with juvenile DM should be considered and requires further study.

Population demographics and socioeconomic impact of osteoporotic fractures in Canada

Through a survey of the literature and an analysis of selected national and regional statistics, a review of the incidence of osteoporosis and its consequences was performed. Results illustrate that the consequences of osteoporosis are preventable and should sensitize clinicians to the importance of early detection and the identification of risk factors for disease prevention and to early treatment once disease has been established. A marked increase in the annual incidence of hip fractures in all Canadians is noted. Whereas the incidence was less than 20,000 in 1981, the incidence of hip fracture grew to 27,342 in 1995, with 73% occurring in women. It is estimated that in Canada at least one in four women older than 50 years will have one or more osteoporosis-related fractures in their lifetimes. The consequences of these fractures are considerable, both for patients and healthcare services. Only half of all victims regain total autonomy, and the total direct costs in Canada stemming from osteoporosis are estimated to be $1.3 billion per year.

Osteopenia and fractures in cystinotic children post renal transplantation

Many of the end-organ effects of cystinosis are known to be risk factors for osteopenia; these include deposition of cystine crystals in bone, hypothyroidism, diabetes mellitus, primary hypogonadism, urinary phosphate wasting, and chronic renal failure. While transplantation may correct the latter, it exposes the child to other risk factors for diminished bone mass, notably the use of high-dose glucocorticoids. Our objective was to determine if these multiple risk factors translate into an increased occurrence of osteopenia, as measured by dual-energy X-ray absorptiometry (DEXA), and/or fractures in this population. We examined the charts, X-rays, and bone mineral density (BMD) of all cystinotic patients post renal transplant for whom this information was available. Lumbar spine BMD was measured by DEXA scan (Hologic 4500). Z-scores were corrected for growth parameters using previously published reference data. Fracture history and pertinent serum markers of bone metabolism were also analyzed. Of the 63 renal transplants performed at our institution, 11 children were transplanted due to cystinosis. Nine of these patients, 5 male and 4 female, had had BMD evaluations, with an average age of 14.3 years (range 5-17 years) at the time of initial BMD post transplant. The mean interval between transplant and BMD evaluation was 39 months (range 3-90 months). Surprisingly, 7 of 9 patients had normal uncorrected BMD values (z-scores -1.92 to +0.02) and 7 of 9 patients had normal corrected values (z-scores -1.20 to +1.93). Three patients suffered from a total of eight fractures. Of the 3 fracture patients, 2 had normal BMD. All patients maintained good graft function and had normal calcium/phosphate mineral status. Of note, 3 of 5 male patients had evidence of primary testicular failure at earlier ages than often described, and this may be an unrecognized risk factor for bone disease in this population. Despite the numerous risk factors for developing osteopenia, these results suggest that the majority of cystinotic patients post renal transplant do not experience reduced bone mineral content as measured by DEXA. However, the significant fracture history among these patients demonstrates that DEXA cannot be used to assess fracture risk in patients with nephropathic cystinosis.

Biocompatibility of three-dimensional chondrocyte grafts in large tibial defects of rabbits

OBJECTIVE

To evaluate biocompatibility and effects of implantation of 3-dimensional chondrocyte-agarose autografts in tibial defects in rabbits and to compare in vitro and in vivo chondrocyte-agarose constructs with respect to cell viability, differentiation, and matrix production.

ANIMALS

24 adult New Zealand White rabbits.

PROCEDURE

Three-dimensional constructs with (grafted group) or without (control group) autogenous chondrocytes were implanted into tibial defects of rabbits and cultured in vitro. During an 8-week period, defects were evaluated radiographically, grossly, histologically, biochemically, and immunohistochemically. In vitro constructs were evaluated histologically, biochemically, and immunohistochemically.

RESULTS

Tibial defects had significantly higher radiographic densitometry values at 4 and 6 weeks after implantation in grafted group rabbits, compared with control group rabbits. Number of observed centers of endochondral ossification was significantly greater in defects of grafted group rabbits, compared with control group rabbits. On day 14, glycosaminoglycan concentration was significantly higher in tibial defects of grafted group rabbits, compared to defects of control group rabbits or in vitro constructs. At weeks 2, 4, and 8, glycosaminoglycan concentrations were significantly lower in the in vitro control constructs, compared with other groups. Collagen type I was present in bone and bony callous in defects of grafted and control group rabbits. Collagen type II was identified in cartilaginous tissues of grafted and control group rabbits. Collagen type X was associated with hypertrophic chondrocytes. Only type II collagen was found in the in vitro chondrocyte constructs.

CONCLUSIONS AND CLINICAL RELEVANCE

Chondrocyte-agarose grafts are biocompatible in large tibial defects and appear to provide a cell source for augmenting endochondral ossification.

Urinary free cortisol increases in adolescent caucasian females during perimenarche

Urinary free cortisol (UFC) excretion has been thought to be constant during female reproductive maturation when normalized for body surface area. We sought to determine whether there are longitudinal changes in urinary free cortisol excretion during perimenarche in adolescent females. We performed a longitudinal study of 24-h UFC excretion obtained at 6-month intervals over a 4-yr period in a cohort of 112 adolescent non-Hispanic white perimenarchal females from south central Pennsylvania. The overall mean values (mean +/- SD) for UFC/24 h for all measurements between ages 12 and 17 yr was 67.4 +/- 43.8 micro g/24 h (to convert to nanomoles per day, multiply by 2.759). In our model, we found a significant positive association between UFC excretion with both gynecological age (P = 0.002) and chronological age (P = 0.0001). For every incremental increase in Tanner stage, the UFC/BSA increased by 3.0 microg/24 h per square meter. Correcting the UFC values by both creatinine and BSA creates a fairly constant number (6.3 +/- 3.1 microg/mg per square meter per 24 h) over the age range 12-17 yr represented in this study. An increase in cortisol excretion may be part of normal reproductive maturation.

Imaging and quantifying skeletal involvement in Gaucher disease

Radiological imaging is used in patients with Gaucher disease to estimate the disease burden, to evaluate the presence of specific skeletal complications and to track response to therapy. MRI is currently the best technique for assessing bone marrow involvement in Gaucher disease. Gaucher cell infiltrated bone marrow is characterized by an abnormal low signal intensity on conventional T1- and T2-weighted spin echo sequences, owing to a reduction in fat marrow, which gives a high signal intensity. Enzyme replacement therapy results in a degradation of Gaucher cell deposits with a reconversion of marrow fat and consequently an increased signal on T(1)-weighted images. Conventional MRI also detects other skeletal complications in Gaucher disease, including oedema resulting from acute bone infarction, infection and trauma, avascular necrosis, pathological fractures and vertebral compression. The main drawback of conventional MRI is that it is not quantitative. Quantitative chemical shift imaging is the most sensitive quantitative method for evaluating bone marrow but is not widely available. Alternative MRI-based methods include calculation of the T1 relaxation constant and proton spectroscopy. Scoring of imaging changes detected on conventional MRI may be useful in estimating disease burden and risk of complications. Dual-energy X-ray absorptiometry (DXA) is sensitive to generalized osteopenia and changes in bone mineral density with extended enzyme replacement therapy. However, DXA is insensitive to local changes and cannot yet be used to predict fracture risk in these patients. Until the ideal quantitative technique is developed, conventional MRI will remain the best diagnostic modality for assessing skeletal complications in Gaucher disease and monitoring response to enzyme replacement therapy.

Does bone change after biliopancreatic diversion?

This prospective study evaluated bone changes after biliopancreatic diversion (BPD) consisting of a distal gastrectomy, a 250 cm alimentary channel, and a 50 cm common channel. Thirty-three consecutive patients had clinical, biochemical, and bone mineral density analysis before surgery and 4 and 10 years after surgery. Iliac crest bone biopsies and special tests including parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), 1,25-dihydroxyvitamin D (1,25-OH(2)-D), bone-specific alkaline phosphatase (BAP), and osteocalcin were obtained at surgery and 4 years postoperatively. Over the years, with close metabolic surveillance, additional calcium and vitamin D were given as indicated. After BPD, serum levels of calcium and vitamin D were decreased and serum levels of PTH, BAP, and osteocalcin were increased. Bone turnover and mineralization were both increased. Mean osteoid volume (P < 0.0007) and bone formation rate in relation to bone volume (P < 0.02) were increased. Static measures of bone were altered as follows: cortical thickness decreased (P < 0.01) and trabecular bone volume increased (P < 0.01). Ten years after surgery, overall bone mineral density was unchanged at the hip and was decreased by 4% at the lumbar spine. Overall fracture risk, based on the Z score, was unchanged. Preoperative factors predicting bone loss included menopause, smoking, and preexisting osteopenia. An elevated level of 1,25-OH(2)-D was also found to be a predictor of future bone loss (r = 0.40; P < 0.002). After surgery, a greater increase in bone markers and bone turnover was associated with an increased risk of bone loss. Although elevated osteocalcin levels were associated with overall bone loss (r = 0.52; P < 0.002), lower albumin levels were associated only with bone loss at hip level (r = 0.44; P < 0.02), whereas lower calcium levels were associated only with the loss at the lumbar spine (r = 0.39; P < 0.02). Ten years after surgery, bone loss at the hip continued to depend on albumin levels (r = 0.37; P < 0.03). We concluded that bone was relatively tolerant to the metabolic changes due to BPD. Provided that there is close surveillance for metabolic disturbances, the use of appropriate supplements, and the avoidance of malnutrition, the beneficial effects of surgery far outweigh the risk of postoperative bone disease.

The female athlete. Before and beyond puberty

As the twentieth century progressed, the female athlete became an accepted participant of sports at all levels. This article reviews various aspects of female sports participation. After an historical perspective, selected comments are provided on psychologic and physiologic aspects. Concepts of adolescent gynecology are reviewed, including breast and menstrual problems and pregnancy. Other areas reviewed include iron deficiency anemia, stress urinary incontinence, and sports injuries in female athletes.

Bone mineral density screening: assessment of influence on prevention and treatment of osteoporosis

OBJECTIVE

To assess the effect of bone mineral density (BMD) screening on the decision to initiate preventive or therapeutic measures for osteoporosis.

METHODS

We offered low-cost BMD screening by dual-energy x-ray absorptiometry of the lumbar spine and proximal femur in conjunction with National Osteoporosis Week. In an effort to assess whether the availability of the BMD measurements resulted in any medical action by the participants of the screening, we conducted a retrospective telephone survey 9 to 12 months after the screening.

RESULTS

In response to a newspaper promotion, 350 subjects underwent BMD screening during a 3- to 4-month period. Of these 332 female and 18 male participants, 83% were Caucasian, 10% were Asian, 5% were Hispanic, and 2% were African American. The mean age was 60 +/- 11 years (range, 29 to 93). Osteoporosis (T-score > or = -2.5) was present in 24% and osteopenia (T-score of -1 to -2.49) in 47% of the subjects. A report was sent to the participant and, if requested, also to a specified physician. Of the 350 participants, 249 (238 women and 11 men) responded to the telephone survey. Of these respondents, 63% had sought medical consultation after the BMD screening. Results of the BMD study led to an increase in calcium intake in 32% of female respondents (48% of those with osteoporosis). After BMD measurement, use of osteoporosis therapy approved by the US Food and Drug Administration increased from 38% to 78% of those with osteoporosis.

CONCLUSION

These results suggest that low-cost BMD screening is highly effective in increasing awareness of osteoporosis, prompting medical consultation, and initiating measures for prevention and treatment of osteoporosis.

Adolescent Caucasian mothers have reduced adult hip bone density

OBJECTIVE

To determine the long-term effect of full term teen pregnancy on peak hip bone mineral density.

DESIGN

Longitudinal observational study.

SETTING

Academic clinical research center.

PATIENT(S)

Sixteen non-Hispanic white females: 4 cases and 12 matched controls who are part of The Penn State Young Women's Health Study and have been studied from ages 12 to 21.

MAIN OUTCOME MEASURES

Four of the subjects had uncomplicated full-term pregnancies between ages 16.5 and 19.5 years.

INTERVENTION(S)

The cases and controls were matched for body mass index at age 12 years, total body bone mineral content at age 12 years, age of menarche, and sports-exercise score during ages 12-18 years. They were then compared with respect to bone measures, cardiovascular disease risk factors, and endocrine profiles at ages 19-21 years.

RESULT(S)

The four teen mothers had significantly lower adult hip bone mineral density than did the controls (0.89 g/cm(2) vs. 0.99 g/cm(2); P=.03). The reproductive hormone patterns of the cases were not statistically significantly different from those of the controls, yet the cases showed a postmenopausal blood lipid pattern.

CONCLUSION(S)

The persistent reduction in hip bone mineral density of the cases is consistent with significantly increased risk of future hip fracture.

Bone mineral decrements in survivors of childhood acute lymphoblastic leukemia: frequency of occurrence and risk factors for their development

We assessed the clinical and treatment factors that predispose survivors of childhood acute lymphoblastic leukemia (ALL) to low bone mineral density (BMD). Using quantitative computed tomography, we determined the frequency of low BMD (defined as >1.645 standard deviations (SD) below the mean) in leukemia survivors treated with multiagent chemotherapy including prednisone and antimetabolite. All participants had completed therapy at least 4 years earlier, remained in continuous complete remission, and had no second malignancies. We statistically correlated BMD results with patient characteristics and treatment histories. Among 141 survivors (median age, 15.9 years; median time after diagnosis, 11.5 years), median BMD z score was -0.78 SD (range, -3.23 to 3.61 SDs). Thirty participants (21%; 95% confidence interval, 15% to 29%) had abnormally low BMD, a proportion significantly (P < 0.0001) greater than the expected 5% in normal populations. Risk factors for BMD decrements included male sex (P = 0.038), Caucasian race (P < 0.0001), and cranial irradiation (P= 0.0087). BMD inversely correlated with cranial irradiation dose. BMD z scores of patients who received higher doses of antimetabolites were lower than those of other patients. Childhood ALL survivors are at risk to have low BMD, especially males, Caucasians, and those who received cranial irradiation.

Bone status in primary hyperparathyroidism

Traditional bone involvement, such as osteoitis fibrosa, has become very rare (< 1%) in primary hyperparathyroidism (PHPT); nevertheless, fractures seem more frequent than in controls, with a predilection for fractures of the distal extremity of the radius, pelvis, ribs and vertebrae, and a relative modest incidence of fractures of the upper extremity of the femur. Histo-morphometric studies have stressed a discrepancy between cortical and trabecular bone with an increase of bone remodeling. The cortical width is constantly diminished and the cortical porosity is increased whereas trabecular volume is normal and micro-architecture preserved. Bone mineral density (BMD) allows an early diagnosis of bone disease and takes a growing place in the management of patients. Since the consensus conference in 1991, the measurement of BMD has been incorporated in the surgical decision with a threshold: Z-score < -2. The demineralisation predominates on sites rich in cortical bone (1/3 proximal of the distal radius); the radius, which was the first site evaluated for technical reasons, is also the most discriminating one. Spine demineralisation is met in more severe forms and BMD measurement of the whole body is promising but requires more studies. In the absence of a radical processing, moderate forms remain stable, whereas more severe forms have a tendency to deteriorate. The evaluation of spine and femoral BMD is useful for the follow-up because the bone gain after parathyroidectomy is significant early on at these sites (rich in trabecular bone with high bone turnover), whereas the BMD of radius is relatively stable.

Osteoporosis in a north american adult population with celiac disease

OBJECTIVE

Osteoporosis, common in European and South American adults with celiac disease, has not been reported in those patients with celiac disease residing in North America. We therefore evaluated bone density in a group of patients from the United States.

METHODS

Patients (105 women and 23 men) with celiac disease, who had completed a questionnaire and had bone mineral density (BMD) measured by dual energy x-ray absorptiometry, were evaluated. The patients were an average age of 56 yr old (range 21-83 yr) and had been on a gluten-free diet from 0 months to 46 yr (mean 7.5 yr).

RESULTS

Osteoporosis (T score < -2.5) was present in 34% of the patients at the lumbar spine, 27% at the femoral neck, and 36% at the radius. Low bone mass (T score between -1.0 and -2.5) was present in 38% at the lumbar spine, 44% at the femoral neck, and 32% at the radius. When compared to age-matched controls, men were more severely affected than women. BMD did not differ between those on a gluten-free diet and those who had not begun therapy. BMD was remeasured 16 +/- 2 months after beginning a gluten-free diet in 5 patients; it increased by 7.5% at the femoral neck (p < 0.02). In 16 patients who had followed a gluten-free diet for an average of 12 yr, BMD remained stable over an additional 2 yr of observation.

CONCLUSIONS

Osteoporosis and low bone mass often affect North American adults with celiac disease, whether or not they are on dietary therapy. Routine screening for osteoporosis is indicated in patients with celiac disease.

The clinical impact of metabolic bone disease in coeliac disease

Bone mineral density was measured by dual energy x ray absorptiometry (DEXA) at the lumbar spine and femoral neck in 15 adults who had metabolic bone disease in association with coeliac disease (mean age at diagnosis 53.5 years, range 37 to 66). Results were expressed as a T score (the number of standard deviations by which patient's bone density differed from the sex matched young adult mean). Three patients had no skeletal symptoms and normal routine calcium biochemistry but severely reduced axial bone mineral density on DEXA. Eleven patients had symptomatic skeletal fractures, including fractures of proximal femur (3), vertebrae (4), and radius (6). Three patients had osteomalacia confirmed on bone biopsy, two of whom had characteristic biochemistry. Secondary and tertiary hyperparathyroidism were seen. Seventy five further patients (60 female) with coeliac disease (mean age 52.0 years, median duration of gluten-free diet 3.4 years) and 75 paired healthy age and sex matched controls were questioned on past fracture history. Patients with coeliac disease underwent detailed studies of calcium biochemistry, dietary intake, and bone mineral density. Sixteen had a past history of fractures (chi(2) = 10.7, p = 0.0004, v controls), which were of typical osteoporotic type. Ten patients had fracture before diagnosis of coeliac disease and six after diagnosis. Patients who had a fracture were older (56.3 v 50.3 years, p < 0.02, Wilcoxon rank sum test) than those with no fracture. There was no significant difference in bone mineral density (z score -0.31 v -0. 77), serum calcium (2.30 v 2.26 mmol/l), 25-hydroxyvitamin D (19.7 v 23.7 nmol/l), parathyroid hormone (2.6 v 3.1 pmol/l), or dietary calcium intake (1021.0 v 1033.0 mg/day) in patients with fracture compared with those without fracture. Metabolic bone disease is common in coeliac disease and is associated with premature osteoporotic fractures.

Longitudinal study of age- and menopause-related metacarpal index changes in Japanese adult females

To establish a comprehensive mode for cortical bone thinning rate, the metacarpal index (MCI) of the index finger of the nondominant hand was measured using computed X-ray microdensitometry. Statistical analysis was used to study the MCI data in relation to age and menopausal status. A total of 383 healthy Japanese women ranging in age from 30 to 79 yr were investigated in 1996 and 1999. The MCI was generally decreased by 1.11% per year. However, accelerative decreases of 1.78 and 2.05% per year were observed within both the age 50-59 yr group and the early postmenopausal period, respectively. In addition, analysis of age-based longitudinal data showed that the age-related loss of MCI in the age 50-59 yr category was significantly higher than that in the other age categories (p < 0.01), indicating that the changes in MCI were more dependent on menopausal status than on aging. Our study suggests that the cortical bone thinning rate is affected by both aging and menopausal status, but the latter may be a predominant factor.