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Elevated tryptase levels are associated with greater bone density in a cohort of patients with mastocytosis.

BACKGROUND: Mastocytosis is associated with a pathological increase in tissue mast cells. Associated skeletal problems include a decrease in bone density and pathological fractures. METHODS: In order to explore the relationship between bone density and the severity of mastocytosis, 21 patients with mastocytosis who underwent dual-energy X-ray absorptiometry were entered into this study. Correlation coefficients were computed between Z-scores and demographic, clinical and laboratory data. Femoral neck Z-scores correlated with serum tryptase levels when all the patients were considered (p=0.029). RESULTS AND CONCLUSION: Patients with less severe disease had significantly lower values at the L1-L4 spine (p=0.046) and femoral neck (p=0.029) Z-scores compared to patients with more severe disease. Most patients who had low Z-scores (between -1 and -2.5) were under 50 years of age, had less severe disease and had lower serum tryptase levels. A history of gastroesophageal reflux disease and a history of hypotensive episodes correlated with lower L1-L4 spine Z-scores (p<0.05). Thus, patients with less severe disease and lower serum tryptase levels should in particular have their bone density determined with treatment appropriate to the findings.

Absorptiometry, Photon↗

[Experimental validation of DXA and MRI-based bone density measurement by ash-method].

Different methods have been established for bone density measurements such as dual energy X-ray absorptiometry (DXA), quantitative computertomography (QCT), and scintigraphy (VQ-Scan). There are hints that magnetic resonance imaging (MRI) might become a new option for the evaluation of bone density. The aim of this study was to investigate correlations between MRI vs. DXA and MRI vs. mineral content of lumbar vertebrae. Data were obtained from ten lumbar vertebral bodies of cattles. The T-1 MRI-sequences SE, PS, and the T-2 Sequence STIR were used for analysis. Total pixel numbers and a pixel per area ratio were determined. Values were compared to DXA-measurements, to the wet weight, and to separated measurements of the spongious, trabecular, and total mineral content of the vertebral body after ashing. We found correlations between DXA (g/vertebral body) vs. mineral content by ash-method (0.918; p < 0.01), DXA vs. MRI (SE-sequence) (-0.872; p < 0.01), and MRI (SE-sequence) vs. mineral content (0.775; p < 0.01). No correlations were found between PS- or STIR-sequences and the ash-method. This study shows that the determination of the bone mineral content of vertebrae is possible applying MRI in the T1-weighted SE-sequence. Without radiation, the MRI provides additionally early detection of trabecular lesions, fractures, and deformities at the spine, without other diagnostic procedures becoming necessary.

Absorptiometry, Photon↗

Bone density in women with endometriosis.

OBJECTIVE: To evaluate the impact of endometriosis on bone metabolism. MATERIALS AND METHODS: We compared bone mineral density and biochemical markers (plasma osteocalcin, bone alkaline phosphatase, fasting urinary hydroxyproline, urinary excretion of cross-linked N-telopeptide of type I collagen) of bone turnover in forty-nine perimenopausal women undergoing laparotomy because of benign gynecologic pathology: in twenty-four of them (group A) endometriosis was diagnosed, the remaining twenty-five represented the control group (group B). Statistical analysis was performed by means of Student "t"-test; significance was set at p < 0.05. RESULTS: Bone density of the lumbar spine (0.898 +/- 0.325 vs 0.940 +/- 0.350) and bone markers failed to show statistically significant differences between the two groups. No significant correlation was observed between any bone density measurement and severity of endometriosis. CONCLUSION: Endometriosis does not seem to induce even in advanced stages, a reduction of bone density.

Adult↗

The effect of a weighted vest on perceived health status and bone density in older persons.

To assess the effect of an exercise intervention using a weighted vest on perceived health status and bone density in older persons, we enrolled 36 seniors in a randomized controlled trial. The vest-use group met weekly for 1 h for a low level exercise class. They wore a weighted vest during the class and as tolerated at home. The discussion controls met for 1 h weekly. At baseline and follow-up (20 weeks), subjects completed a questionnaire that included the 20 item MOS Short-Form Health Survey, Multidimensional Health Locus of Control Scale, and Philadelphia Geriatric Center Morale Scale, and bone density was measured by dual energy X-ray absorptiometry. Subjects also completed daily activity diaries. Subjects in the vest group reported a statistically significant decrease in bodily pain, improved physical functioning, and increased internal health locus of control. Bone density increased by 1% in the vest group and decreased by 0.6% in the controls (p = 0.12). We conclude that our exercise intervention had a positive effect on some measures of perceived health in older persons.

Age Factors↗

A double-blind randomised controlled trial of the effects of medroxyprogesterone acetate on bone density of women taking oestrogen replacement therapy.

OBJECTIVE: To assess the effects of medroxyprogesterone acetate on bone density in women who have had a hysterectomy. DESIGN: Randomised, double-blind, placebo-controlled trial of medroxyprogesterone acetate 10 mg, 20 mg or placebo as an adjunct to oestrogen therapy. PARTICIPANTS: One hundred and twenty-three women, aged 18 to 45 years and currently receiving daily oestrogen, who presented at a university-based rheumatology practice. INTERVENTIONS: The women were randomly assigned to receive either medroxyprogesterone acetate 10 mg, 20 mg or placebo daily beginning on day 15 of each month for one year. Forty-one women were randomised into each group. MAIN OUTCOME MEASURE: The primary outcome measurement was the percentage of change from baseline in bone mineral density of the lumbar spine (L2-L4). Secondary outcome measures included differences in femoral neck bone density, cholesterol and triglyceride levels between groups. RESULTS: At one year, change in bone mineral density did not differ between either the treatment or placebo groups. Medroxyprogesterone acetate 20 mg and 10 mg led to statistically significant reductions in very low density lipoprotein cholesterol, total triglycerides, and very low density lipoprotein triglycerides when compared with placebo. Medroxyprogesterone acetate 20 mg also led to a statistically significant reduction in high density lipoprotein cholesterol, high density lipoprotein-2 cholesterol, and high density lipoprotein-2 triglycerides. CONCLUSIONS: Medroxyprogesterone acetate at either dose as an adjunct to oestrogen did not improve bone mineral density at one year when compared with placebo. Medroxyprogesterone acetate 10 mg may not adversely affect lipids. Medroxyprogesterone acetate 20 mg, however, did reduce high density lipoprotein cholesterol and therefore may increase cardiovascular risk.

Adolescent↗

Soluble cathepsin-L: a marker of bone resorption and bone density?

We sought to evaluate cathepsin L serum levels in the peripheral blood of patients with low bone density. Blood samples from 60 patients (32 osteoporotic, 28 osteopenic) and 16 healthy controls were taken and quantitative measurements of cathepsin L were performed with the use of a commercially available enzyme-linked immunosorbent assay. Dual x-ray absorptionometry measurements and serum levels of alkaline phosphatase, bone-specific alkaline phosphatase, osteocalcin, parathyroid hormone, sexual hormones, and N -terminal crosslinks of type I collagen were examined. Group comparisons between patients with osteoporosis and controls showed significant differences with respect to cathepsin L ( t = -2.839; df = 29; P =.008). Osteoporosis treatment decreased the serum level of cathespsin L in a statistically significant fashion ( P =.002). These results suggest that the serum level of cathepsin L can serve as a marker of bone resorption and bone density.

Aged↗

Calcitonin and calcium combined therapy in osteoporosis: effects on vertebra trabecular bone density.

Calcitonin is a hormone produced by the parafollicular cells of the thyroid gland. Like calcium salts, calcitonin acts by reducing bone resorption. In this study, 26 osteoporotic patients were given 100 IU salmon calcitonin for 10 days and, thereafter, 100 IU calcitonin every other day for 80 days combined with 1000 mg/day calcium salts. Prior to and after the combined therapy, the mean trabecular bone densities from the levels of thoracic 12 and lumbar 1 and 2 were obtained and routine thoracic and lumbar radiography performed. Combined calcitonin and calcium therapy for 3 months produced significant increases in vertebra trabecular bone density. The evaluation of the trabecular bone density and the number of non-traumatic compression fractures in 26 osteoporotic patients prior to the therapy did not indicate any close relationship between them. It is concluded that, in addition to other factors reported previously, microtraumas during daily activities have some effect on the incidence of fractures.

Bone and Bones↗

Environmental exposure to cadmium, forearm bone density, and risk of fractures: prospective population study. Public Health and Environmental Exposure to Cadmium (PheeCad) Study Group.

BACKGROUND: Chronic low-level exposure to cadmium may promote calcium loss via urinary excretion. We undertook a prospective population study to investigate whether environmental exposure to cadmium lowers bone density and increases risk of fractures. METHODS: We measured urinary cadmium excretion, a biomarker of lifetime exposure, in people from ten districts of Belgium, of which six districts bordered on three zinc smelters. We also measured cadmium in soil and in vegetables from the districts, and collected data on incidence of fractures and height loss. Bone density was measured at the forearm just above the wrist by single photon absorptiometry, and calculated as the mean of six proximal and four distal scans. FINDINGS: Mean cadmium excretion at baseline was 8.7 nmol daily. Across the ten districts, mean cadmium concentration in soil ranged from 0.8 to 14.7 mg/kg, and from 0.1 to 4.0 mg/kg dry weight in vegetables. Median follow-up was 6.6 years. Mean forearm bone density in proximal and distal scans was 0.54 g/cm2 and 0.43 g/cm2 in men, and 0.44 g/cm2 and 0.34 g/cm2 in women. In postmenopausal women, a twofold increase in urinary cadmium correlated with 0.01 g/cm2 decrease in bone density (p<0.02). The relative risks associated with doubled urinary cadmium were 1.73 (95% CI 1.16-2.57; p=0.007) for fractures in women and 1.60 (0.94-2.72, p=0.08) for height loss in men. Cadmium excretion in districts near smelters was 22.8% higher (p=0.001) than in other districts, with fracture rates of 16.0 and 10.3 cases per 1000 person-years, respectively, and a population-attributable risk of 35.0%. INTERPRETATION: Even at a low degree of environmental exposure, cadmium may promote skeletal demineralisation, which may lead to increased bone fragility and raised risk of fractures.

Absorptiometry, Photon↗

Effect of bone density information on decisions about hormone replacement therapy: a randomized trial.

OBJECTIVE: To determine the effect of bone density information on a woman's decision about hormone replacement therapy (HRT). METHODS: One hundred forty women were assigned randomly to receive either educational information about osteoporosis and a voucher for a bone mineral density test 12 months later or the same educational information plus an immediate dual-energy x-ray absorptiometry test for bone mineral density. Women in both groups were offered prescription for HRT. RESULTS: Of the 93 women who received a bone mineral density test, 63.4% elected HRT and filled their prescription, compared with only 20.0% of the 43 women who did not have a bone mineral density test (P < .01). Women who were classified as osteopenic (between -1 and -2.5 standard deviations [SDs] of the young normal bone mineral density) or osteoporotic (more than 2.5 SDs below young normals) were more likely to choose HRT (69.4%) than were women whose bone mineral density was in the normal range (51.6%) (above -1 SD of the young normal bone mineral density value). CONCLUSIONS: A bone mineral density test, regardless of the result, had a significant effect on women's decisions to accept HRT. Within the group having the test, women with lower bone mineral density were more likely to choose HRT.

Absorptiometry, Photon↗

Interactions of insulin-like growth factor I with dexamethasone on trabecular bone density and mineral metabolism in rats.

Glucocorticoid treatment causes osteoporosis and growth retardation in humans. Insulin-like growth factor I (IGF-I) stimulates differentiation and replication of cultured osteoblast-like cells and induces longitudinal bone growth in IGF-I-deficient rats. We investigated the influence of subcutaneously infused IGF-I on bone and mineral metabolism of male rats treated with a high dose of dexamethasone. Dexamethasone was added to the drinking water in a concentration of 1 mg/l. After 30 days of dexamethasone treatment, recombinant human IGF-I (300 micrograms/day) or solvent was infused sc by osmotic minipumps for 21 days while dexamethasone was continued. Age-matched untreated male rats served as healthy controls. Dexamethasone-treated rats lost weight. Their IGF-I levels were decreased to 36% of healthy controls. Infusion of IGF-I resulted in an increase in IGF-I serum levels (582% compared to healthy controls) and allowed some weight gain. Osteocalcin and calcitriol levels were markedly decreased in dexamethasone-treated rats and were not influenced significantly by IGF-I infusion. In contrast, IGF-I treatment restored the free calcitriol concentration (molar ratio of calcitriol to vitamin D-binding protein) towards normal. Furthermore, infusion of IGF-I partially corrected the dexamethasone-induced hyperinsulinemia. Histomorphometric analysis revealed no difference in vertebral trabecular bone density (i.e. growth-independent bone remodeling) between the three groups. In contrast, mean trabecular bone density in tibial metaphyses was increased markedly by dexamethasone, presumably due to osteoclast inhibition. Insulin-like growth factor I infusion did not significantly influence these structural metaphyseal bone parameters.(ABSTRACT TRUNCATED AT 250 WORDS)

Alkaline Phosphatase↗

The range of bone density in normal British women.

A study to determine the range of bone density in British females was carried out on a group of 165 normal women. The results showed an increase in mineral content with peak values occurring in the fourth decade (mean 1.06 g/cm2; 95% confidence limits 0.783-1.343) and subsequent decline with increasing age. There was no significant effect from any risk factor but strict exclusion criteria were applied. The results from each age group were compared with those from the USA and showed a difference in the timing of peak bone density (third decade for the USA). Age-matched, clinically well-defined normal controls should be used for comparison with groups of patients in future studies.

Absorptiometry, Photon↗

Association between calcium ingested from drinking water and femoral bone density in elderly women: evidence from the EPIDOS cohort.

Although the main source of dietary calcium is dairy products, the calcium contained in mineral water, which is as available as that of milk, could provide a valuable source of calcium. We analyzed the data from the EPIDOS multicenter study to evaluate the relationship between both dietary calcium and that supplied by drinking water and bone density measured at the femoral neck by dual-energy X-ray absorptiometry. The study included 4434 women over 75 years of age who had not received any treatment likely to interfere with calcium metabolism. A significant correlation was found between total calcium intake and bone density at the femoral neck (r = 0.10, p < 0. 001). After adjustment for the main variables influencing bone density, an increase of 100 mg/day in calcium from drinking water was associated to a 0.5% increase in femoral bone density, while a similar increase in dietary calcium from other sources only led to a 0.2% increase; however, this difference was not significant. The consumption of calcium-rich mineral water may be of interest, especially in older women who consume little calcium from dairy products.

Absorption↗

Birth weight, birth length, and bone density in prepubertal children: evidence for an association that may be mediated by genetic factors.

There is an incomplete understanding of the contribution of early growth to bone accrual in childhood. The aims of this longitudinal study were to examine the association between growth variables at birth, 1 month, and 8 years and bone density in prepubertal children. Weight and length at both birth and 1 month of age were measured in 1988 as part of a prospective study for sudden infant death syndrome. A total of 330 children (47%) and 278 of their mothers were then contacted in 1996 for measurement of anthropometrics and bone density. Birth weight, birth length, and length gain (but not weight gain) in the first month all made significant contributions to areal bone density (BMD, g/cm(2)) at all sites at age 8 even after taking into account subsequent weight and height gain (model R(2) 14-39% depending on variable and site). Adjustment for potential environmental confounders did not alter these findings, however, adjustment for maternal BMD markedly reduced the early life associations (particularly for birth weight). Though early life factors were weakly associated with bone mineral apparent density (BMAD, g/cm(3)) in correlation analysis, subsequent height and weight gain were the only significant independent contributors to BMAD. In conclusion, early life anthropometrics make little contribution to BMAD (other than through their correlation with later growth) but make significant independent contributions to BMD suggesting that the growth trajectory of bone is determined very early in life. In addition, the contribution of body size at birth to bone growth in early life appears to be mediated by genetic factors although it is possible that it may be mediated by poorly measured or as yet unidentified determinants of body size at birth.

Absorptiometry, Photon↗

How reliable is a radiological report in osteoporosis in diagnosing low bone density?

Patients are often referred to osteoporosis clinics with a radiological diagnosis of osteoporosis. Previous studies attempting to ascertain risk of osteoporosis from radiographs have been conflicting. The aim of our study was to determine how reliable spinal radiographs were at detecting low bone density compared with Dual Energy X ray Absorptiometry (DXA). We retrospectively measured the Bone Mineral Density (BMD) at the spine in 130 patients with a radiological diagnosis of osteopenia or osteoporosis in the absence of vertebral fractures. They were compared with a group of 119 age and sex matched patients with one or more low trauma vertebral fractures. There was a statistically significant difference in the mean BMD between these two groups. 12.7%, of the x-ray group with osteopenia reported, had a normal bone density, 49.2% had osteopenia (T-score -1 to -2.5) and 38.1% had osteoporosis (T-score <-2.5). Of those with a radiological report of osteoporosis, 12.8% had a normal bone density, 44.7% had osteopenia and 42.6% had osteoporosis. We conclude that a radiological report of low bone density is a strong predictor of osteopenia or osteoporosis by BMD measurement.

Absorptiometry, Photon↗

Bone density in ageing Caucasian and African populations.

Fracture surveys in the Johannesburg metropolitan area showed that the rate of femoral-neck fractures rose sharply after the climacteric in Caucasians, whereas the incidence of such fractures in African Negroes of the same age was almost negligible. However, a parallel epidemiological survey of metacarpal bone density in random samples of the same populations showed that absolute values for skeletal mass and bone density were greater in the Caucasians through most of the age-range from 5 to 75 years. Also, although bone density increased more rapidly and reached higher maximum values in young Caucasians than in Africans, it fell more rapidly in the former from the fourth decade onwards. The differences in the pattern of bone density alone are unlikely to account for the large difference in the fracture rates in the two populations. Perhaps quantitative changes in bone mass associated with ageing are accompanied by qualitative changes which may be critical in determining the liability to fracture.

Adolescent↗

Impact of bone density corrections on target dose delivered to the prostate with 4 MV, 6 MV, 10 MV, and 18 MV photons.

Doses for definitive prostate irradiation have been derived empirically using low-energy megavoltage equipment without availability of bone density corrections. With their increased availability, higher energy photons are being used more frequently because of their improved depth of penetration. Although inhomogeneity corrections lead to greater accuracy of dose delivery, the clinical utility of corrections in the pelvis is unclear. This study evaluates the effect of bone density on the dose delivered with respect to the photon energy employed. Contours and volumes for 10 patients were taken from computed tomography scans at the center of the prostate gland. Treatment plans for bilateral prostate arc fields were run on the Capintec Treatment Planning System for 4, 6, 10, and 18 MV photon energies. The monitor units needed to deliver 6500 cGy to isocenter without bone correction were used for calculations, both with and without bone correction using the equivalent path length algorithm. The median dose to the isocenter was 6500 cGy for all energies without bone correction. The median doses using the uncorrected monitor units for the 4 MV, 6 MV, 10 MV, and 18 MV photon beams corrected for bone density were 6033, 6062, 6166, and 6228 cGy, respectively. The variance in target doses observed in our patient sample was +/- 2.3%, +/- 2.2%, +/- 1.7%, and +/- 1.4%, respectively, for the 4 MV, 6 MV, 10 MV, and 18 MV beams with bone correction. The increased density of bone in the pelvis does alter the actual dose to the prostate from external beam treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Density↗

Bone density around titanium implants may benefit from smoking cessation: a histologic study in rats.

PURPOSE: This study tested the hypothesis that interruption of cigarette smoke inhalation (CSI) would reverse its impact on bone quality around implants. MATERIALS AND METHODS: Sixty-nine rats were assigned to 1 of 4 groups. Group 1 (n = 16) was the control group; group 2 experienced CSI for the duration of the study (150 days); group 3 experienced CSI for 83 days prior to implant placement, until 7 days prior to implant placement, when CSI ceased; and for group 4, CSI exposure was temporarily halted from 7 days before implantation to 21 days afterward. Bone density (the proportion of mineralized bone in a 500-microm-wide zone lateral to the implant) was calculated for each specimen (mean +/- SD). RESULTS: In the cortical bone, a slight difference in bone density was noted between the groups (97.66% +/- 3.69% for group 1, 98.30% +/- 0.95% for group 2, 98.83% +/- 0.73% for group 3, and 98.11% +/- 1.14 for group 4; P > .05). In contrast, continuous exposure to cigarette smoke (group 2) significantly decreased density in the cancellous bone in comparison to the other groups (25.69% +/- 9.41% for group 1, 18.08% +/- 6.0% for group 2, 25.46% +/- 5.42 for group 3, and 26.20% +/- 6.77% for group 4; P < .05), with no significant differences between groups 1, 3, and 4 (P > .05). DISCUSSION: The results support the concept that the effects of cigarette consumption on dental implants may be reversible, and therefore suggest that smokers may realize satisfactory outcomes if they cease smoking, even temporarily. CONCLUSION: In conclusion, smoking may affect bone quality around titanium implants in cancellous bone, and cessation could result in a return toward to the levels of the control group.

Alveolar Bone Loss↗

Broadband ultrasound attenuation compared with dual-energy X-ray absorptiometry in screening for postmenopausal low bone density.

Broadband ultrasound attenuation (BUA) was investigated as an inexpensive, simple and radiation-free method of screening for low perimenopausal bone density. A total of 587 women (50-54 years), invited for screening had bone mineral density (BMD) measured at the femoral neck and the lumbar spine by dual-energy X-ray absorptiometry (DXA). At the same visit the BUA of the calcaneus was measured. The correlation between BUA and BMD was approximately 0.4 compared with 0.67 between femoral neck and spinal BMD. Receiver operating characteristic (ROC) curve analysis demonstrated BUA to have the same ability for discriminating between low BMD at either the femoral neck or lumbar spine. BUA with a cut-off for normality at the median (BUA = 80) had a sensitivity of 68% and specificity of 67% for low bone density identified by a BMD less than the 25th centile at the femoral neck or lumbar spine. The correlation between BUA and BMD was insufficient to allow identification of the same groups as having low bone density.

Absorptiometry, Photon↗