With the increasing number of quantitative ultrasound (QUS) devices in use worldwide it is important to develop strategies for the clinical use of QUS. The aims of this study were to examine the age-dependence of T-scores and the prevalence of osteoporosis using the World Health Organization Study Group criteria for diagnosing osteoporosis and to examine the T-score threshold that would be appropriate to identify women at risk of osteoporosis using QUS. Two groups of women were studied: (i) 420 healthy women aged 20-79 years with no known risk factors associated with osteoporosis; (ii) 97 postmenopausal women with vertebral fractures. All subjects had dual-energy X-ray absorptiometry (DXA) measurements of the spine and hip and QUS measurements on three calcaneal ultrasound devices (Hologic Sahara, Hologic UBA575+, Osteometer DTUone). A subgroup of 102 (76 on the DTUone) healthy women aged 20-40 years was used to estimate the young adult mean and SD for each QUS and DXA measurement parameter to calculate T-scores. The age-related decline in T-scores for QUS measurement parameters was half the rate observed for the bone mineral density (BMD) measurements. The average T-score for a woman aged 65 years was -1.2 for QUS measurements and -1.75 for the BMD measurements. When osteoporosis was defined by a T-score < or = -2.5 the prevalence of osteoporosis in healthy postmenopausal women was 17%, 16% and 12% for lumbar spine, femoral neck and total hip BMD respectively. When the same definition was used for QUS measurements the prevalence of osteoporosis ranged from 2% to 8% depending on which ultrasound device and measurement parameter was used. Four different approaches, based on DXA-equivalent prevalence rates of osteoporosis, were utilized to examine which T-score threshold would be appropriate for identifying postmenopausal women at risk of osteoporosis using QUS measurements. These ranged from -1.05 to -2.12 depending upon the approach used to estimate the threshold and on which QUS device the measurements were performed, but all were significantly lower than the threshold of -2.5 used for BMD measurements. In conclusion, the WHO threshold of T = -2.5 for diagnosing osteoporosis requires modification when using QUS to assess skeletal status. For the three QUS devices used in this study, a T-score threshold of -1.80 would result in the same percentage of postmenopausal women classified as osteoporotic as the WHO threshold for BMD measurements. Corresponding T-score thresholds for individual measurement parameters on the two commercially available devices were -1.61, -1.94 and -1.90 for Sahara BUA, SOS and estimated heel BMD respectively and -1.45 and -2.10 for DTU BUA and SOS respectively Additional studies are needed to determine suitable T-score thresholds for other commercial QUS devices.

The CYP 17 and CYP 19 genes encode 17alpha-hydroxylase/17,20-lyase and aromatase, respectively, both involved in sex hormone synthesis. We investigated the association between 2 common polymorphisms in 1) the promoter region (T-->C substitution) of CYP 17, and 2) exon 3 (G-->A) of CYP 19, bone mineral density (BMD) and serum androgen/estradiol, in a case-control study of 252 postmenopausal women aged 64.5 +/- 9.2 yr (mean +/- SD). There was no significant difference in serum estradiol concentrations between cases (n = 136) and controls (n = 116). The CYP 19 genotype was significantly associated with serum estradiol (P = 0.002). Women with the AA genotype had higher serum estradiol concentrations compared with those with the GG genotype (P = 0.03). In older women, those with the CYP 19 GA and GG genotypes had an increased prevalence of osteoporosis (P = 0.04) and fractures (P = 0.003). We found no significant association between CYP 17 genotype and serum androgens and estradiol concentrations. However, a significant association was seen between BMD values at the femoral neck with CYP 17 genotype in cases (P = 0.04) and in the whole study population (P = 0.012). Subjects with the CC genotype had significantly lower BMD (mean +/- SD: TT, 0.7 +/- 0.16; CC, 0.6 +/- 0.08 g/cm(2); P = 0.006). In conclusion, both CYP 17 and CYP 19 are candidate genes for osteoporosis in postmenopausal women.

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ObjectivesOur aim was to examine the relationship of arterial stiffness to measures of atherosclerosis, arterial calcification, and bone mineral density (BMD); the heritability of these measures; and the degree to which they are explained by common genetic influences.BackgroundArterial stiffening relates to arterial calcification, but this association could result from coexistent atherosclerosis. A reciprocal relationship between arterial stiffening/calcification and BMD could explain the association between cardiovascular morbidity and osteoporosis.MethodsWe examined, in 900 women from the Twins UK cohort, the relationship of carotid-femoral pulse wave velocity (cfPWV) to measures of atherosclerosis (carotid intima-media thickening; carotid/femoral plaque), calcification (calcified plaque [CP]; aortic calcification by computed tomography, performed in subsample of 40 age-matched women with low and high cfPWV), and BMD.ResultsThe cfPWV independently correlated with CP but not with intima-media thickness or noncalcified plaque. Total aortic calcium, determined by computed tomography, was significantly greater in subjects with high cfPWV (median Agatston score 450.4 compared with 63.2 arbitrary units in subjects with low cfPWV, p = 0.001). There was no independent association between cfPWV and BMD. Adjusted heritability estimates of cfPWV and CP were 0.38 (95% confidence interval: 0.19 to 0.59) and 0.61 (95% confidence interval: 0.04 to 0.83), respectively. Shared genetic factors accounted for 92% of the observed correlation (0.38) between cfPWV and CP.ConclusionsThese results suggest that the association between increased arterial stiffness and the propensity of the arterial wall to calcify is explained by a common genetic etiology and is independent of noncalcified atheromatous plaque and independent of BMD.

Arterial calcification leading to increased arterial stiffness, a powerful risk factor for cardiovascular disease, may underlie the association of osteoporosis with cardiovascular disease in postmenopausal women. Osteoprotegerin (OPG), an indirect inhibitor of osteoclastogenesis, may be involved in arterial calcification. We examined relationships between calcification of subclinical atherosclerotic plaque and arterial stiffness with bone mineral density (BMD) and OPG in a group of 54 postmenopausal women referred for routine osteoporosis screening by dual-energy X-ray absorptiometric scanning of the lumbar spine and hip. Presence of calcified and noncalcified plaque in carotid and femoral arteries was examined using ultrasonography. Pulse wave velocity (PWV), a measure of arterial stiffness, was determined by sequential tonometry over the carotid and femoral region. Fifty-nine percent of osteoporotic women had calcified (echogenic) plaque at one or more sites compared with 42% and 20% for women with osteopenia and normal BMD, respectively (P = 0.04). There was a significant negative correlation between PWV and hip BMD (r = -0.35, P = 0.01), which remained significant when age, mean arterial pressure, and serum lipids were taken into account (P = 0.05). No significant relationships were observed between serum concentrations of OPG and lumbar spine or total hip BMD or with the number of arterial sites with calcified or noncalcified plaque. However, there was a strong correlation between OPG and PWV (r = 0.44, P = 0.001), which remained significant when adjusted for age (P = 0.01). These findings suggest that decreased BMD is associated with arterial calcification and stiffening and raise the possibility that OPG is a marker of arterial stiffening, independent of any association with BMD.

(18)F-Fluoride bone plasma clearance can be estimated from a static scan and venous blood samples acquired 30-60 min after injection. The method enables K ( i ) to be estimated at multiple skeletal sites with a single injection of tracer.

Because resources do not allow all women to be screened for osteoporosis, clinical risk factors are often used to identify those individuals at increased risk of fracture who are then assessed by bone densitometry. The aim of this study was to compare calcaneal quantitative ultrasound (QUS) and axial bone mineral density (BMD) T and Z scores in a large group of women, some with no clinical risk factors and others with one or more risk factors for osteoporosis. The study population consisted of 1115 pre-and postmenopausal women. A subgroup of 530 women was used to construct reference data for calculating T and Z scores. A total of 786 women was found to have one or more of the following risk factors: (i) atraumatic fracture since the age of 25 years, (ii) report of X-ray osteopenia, (iii) predisposing medical condition or use of therapy known to affect bone metabolism, (iv) premature menopause before the age of 45 years or a history of amenorrhea of longer than 6 months duration, (v) family history of osteoporosis, (vi) body mass index (BMI) <20 kg/m 2 , and (vii) current smoking habit. Calcaneal broadband ultrasound attenuation (BUA) and speed of sound (SOS) measurements were performed on a Hologic Sahara and a DTUone and BMD was measured at the spine and hip using dual-energy X-ray absorptiometry (DXA). The Z score decrements associated with the seven risk factors calculated using multivariate regression analysis were similar for QUS and BMD measurements. Z score decrements (mean of BMD and QUS measurements combined) associated with a history of atraumatic fracture (؊0.67), X-ray osteopenia (؊0.36), a family history of osteoporosis (؊0.23), and a low BMI (؊0.53) were all statistically significant compared with women with no risk factors. Z score decrements associated with a medical condition or use of therapy known to affect bone metabolism, a premature menopause or prolonged amenorrhea, or those who were current smokers were not significantly different from zero. As the number of risk factors present in each individual increased, the mean Z score decrements became more negative, increasing from ؊0.28 for women with one risk factor to ؊1.19 for those with four or more risk factors. QUS and BMD measurements yielded similar mean Z scores for women with one, two, three, or more than four risk factors.

Teriparatide increases skeletal mass, bone turnover markers, and bone strength, but local effects on bone tissue may vary between skeletal sites. We used positron emission tomography (PET) to study 18 F-fluoride plasma clearance (K i ) at the spine and standardized uptake values (SUVs) at the spine, pelvis, total hip, and femoral shaft in 18 postmenopausal women with osteoporosis. Subjects underwent a 1-hour dynamic scan of the lumbar spine and a 10-minute static scan of the pelvis and femurs at baseline and after 6 months of treatment with 20 mg/day teriparatide. Blood samples were taken to derive the arterial input function and lumbar spine K i values evaluated using a three-compartment model. SUVs were calculated for the spine, pelvis, total hip, and femoral shaft. After 6 months treatment with teriparatide, spine K i values increased by 24% (p ¼ .0003), while other model parameters were unchanged except for the fraction of tracer going to bone mineral (k 3 /[k 2 þ k 3 ]), which increased by 23% (p ¼ .0006). In contrast to K i , spine SUVs increased by only 3% (p ¼ .84). The discrepancy between changes in K i and SUVs was explained by a 20% decrease in 18 F À plasma concentration. SUVs increased by 37% at the femoral shaft (p ¼ .0019), 20% at the total hip (p ¼ .032), and 11% at the pelvis (p ¼ .070). Changes in bone turnover markers and BMD were consistent with previous trials. We conclude that the changes in bone formation rate during teriparatide treatment as measured by 18 F À PET differ at different skeletal sites, with larger increases in cortical bone than at trabecular sites. ß