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PubMed1989

[The effect of oral contraceptives on bone density in climacteric females].

The aim of the study was to investigate the influence of long-term administration of oral contraceptives on bone density in climacteric women. Two hundred (n = 200) climacteric women were allocated to three study groups (I, II, III). The first (n = 30) one had been using oral contraceptives for more than 10 years, the second (n = 50) one for between 2 and 9 years, while the third (n = 120) one had never used oral contraceptives. Bone mineral content (BMC) of the left forearm was measured by single photon absorptiometry. The results demonstrate that osteoporosis occurs later and is less frequent during the peri-menopause (p less than 0.05) in women who have used oral contraceptives on a long-term basis (greater than 10 yr). Our findings confirm that there is an important correlation between longterm use of oral contraceptives and bone density.

Adult↗

PubMed1999

[Adaptation of computed tomography and roentgenography to bone density measurements].

The increasing interest in issues connected with osteoporosis has recently caused the development of many new diagnostic methods which allow the measurement of bone density. The DEXA method, performed by specialised densitometers, is one of the most developed and reliable methods. However, the high cost od densitometers and DEXA investigation prevent this method from becoming easily accessible for everyday diagnosis. The adaptation of computerised tomography and rentgenography to densitometric measurements could be one of the methods by which the problem of densitometric diagnosis accessibility could be solved. Both methods are usually applied in the imaging of human tissues, working on the basis of differences in tissue X-ray absorption. X-ray absorption and density are related by linear function in the energy range used in rentgenography and tomography; therefore, quantitative information concerning density should be easily received. The procedure adapting computerised tomography and rentgenography to quantitative measurements of bone density in the lumbar spine is outlined in this work. The quantitative information is obtained from digitalised tomographic and rentgenographic images through use of a personal computer. Both methods were tested using a set of phantoms imitating the lumbar spine and the surrounding tissues. The precision and accuracy of both methods were assessed and compared to the precision and accuracy of the DEXA method. The outlined results confirm the usefulness of the described method in diagnosis.

Absorptiometry, Photon↗

PubMed2002

Monitoring bone density in hypogonadal men by quantitative phalangeal ultrasound.

Monitoring bone density (BMD) in hypogonadal and testosterone (T) substituted men is a major component of andrological therapy and is performed by methods that are cost-intensive and use radiation, such as quantitative computer tomography (QCT). Therefore, we assessed the feasibility of a more practical and inexpensive approach through application of phalangeal quantitative ultrasound (pQUS; IGEA DBM BP Sonic 1200, Sensweiler, Germany) in a cross-sectional study of 521 men, aged 18-91 years (224 healthy controls, 156 newly diagnosed hypogonadal, and 141 T substituted men). The method was compared with QCT of the lumbar spine in the first 80 patients. We evaluated longitudinal changes of amplitude-dependent speed-of-sound (AdSoS) in 54 hypogonadal men from the beginning of T substitution. AdSoS decreased with age (p < 0.0001) and with declining total T concentration, with a four to fivefold larger reduction in AdSoS for each nanomole-per-liter decrement in total T in the hypogonadal range (<12 nmol/L) compared with the eugonadal range (p < 0.0001). AdSoS was higher in eugonadal and substituted men than in hypogonadal patients (p < 0.0001, by analysis of covariance [ANCOVA]). Substituted men <50 years of age showed lower AdSoS than eugonadal men (p = 0.004) and untreated men with secondary hypogonadism had lower values than men with primary hypogonadism (p = 0.005). Therapeutic effects were seen regardless of age, diagnosis, or T substitution modality. In the longitudinal approach, AdSoS increased from 1986 +/- 93 to 2035 +/- 77 m/sec over 237 +/- 57 days with the highest gain in those men with initially the lowest values (p < 0.0001, by ANCOVA for repeated measurements). In comparison to QCT, patients with a lumbar content of hydroxylapatite of <100 mg/cm(3) were reliably identified by pQUS (cutoff level 1965 m/sec, T score -3.5 based on eugonadal subjects; receiver operating characteristics: area under the curve [AUC] 0.94, sensitivity 94.1, specificity 92%, p < 0.0001), but specific values of lumbar BMD could not be predicted by pQUS. pQUS represents a feasible, sensitive, and inexpensive method for assessing bone tissue in hypogonadal men over the full age range and also for monitoring the effects of T substitution.

Adolescent↗

PubMedDate not supplied

Bone density and ash studies in avian osteopetrosis.

Bone density and ash were measured in diaphyses of osteopetrotic and normal chicken tibiotarsi. In lesions of less than one year's duration, osteopetrotic bone was less dense than disease-free bone. The new osteopetrotic bone yielded approximately the same ash content per unit bone dry weight, as did disease-free bone of comparable age, but there was consistently less ash per unit bone wet volume in the diseased bones. This indicates that, in its early stages, osteopetrosis is characterized by spongy bone that lacks dense mineral deposition.

Animals↗

PubMed1991

The effects of estrone (Ogen) on spinal bone density of postmenopausal women.

The effects of cyclical treatment with estrone sulfate (0.3, 0.625, or 1.25 mg), plus calcium carbonate, on spinal trabecular bone density were compared with placebo in 120 postmenopausal women in this 2-year, multicenter, double-blind study. While the placebo and 0.3-mg treatment groups lost bone density (-3.6% and -5.1%), the 0.625- and 1.25-mg treatment groups experienced no significant change from baseline at 24 months (-0.8% and +0.7%). The 1.25-mg treatment group was significantly different from the placebo group at 12, 18, and 24 months. Although the 0.625-mg treatment group was significantly different from the placebo group only at 18 months, the data suggest that 0.625 and 1.25 mg of estrone sulfate had different effects than placebo and 0.3 mg of estrone sulfate and, given with supplemental calcium, are effective doses for the prevention of spinal bone loss.

Bone Density↗

PubMed2005

Environmental exposure to cadmium at a level insufficient to induce renal tubular dysfunction does not affect bone density among female Japanese farmers.

Some recent research suggests that environmental exposure to cadmium, even at low levels, may increase the risk of osteoporosis, and that the bone demineralization is not just a secondary effect of renal dysfunction induced by high doses of cadmium as previously reported. To investigate the effect of exposure to cadmium at a level insufficient to induce kidney damage on bone mineral density (BMD) and bone metabolism, we conducted health examinations on 1380 female farmers from five districts in Japan who consumed rice contaminated by low-to-moderate levels of cadmium. We collected peripheral blood and urine samples and medical and nutritional information, and measured forearm BMD. Analysis of the data for subjects grouped by urinary cadmium level and age-related menstrual status suggested that cadmium accelerates both the increase of urinary calcium excretion around the time of menopause and the subsequent decrease in bone density after menopause. However, multivariate analyses showed no significant contribution of cadmium to bone density or urinary calcium excretion, indicating that the results mentioned above were confounded by other factors. These results indicate that environmental exposure to cadmium at levels insufficient to induce renal dysfunction does not increase the risk of osteoporosis, strongly supporting the established explanation for bone injury induced by cadmium as a secondary effect.

Agriculture↗

PubMed1994

Leuprolide acetate depot for the treatment of uterine leiomyomas. Changes in bone density, uterine volume and uterine vascular resistive index.

This study measured the changes in uterine volume, uterine vascular resistive index and lumbar vertebral bone density before and after a six-month course of leuprolide acetate depot in women with uterine leiomyomas. All nine patients studied were black. The high baseline bone density of black women may provide a greater scope for the use of gonadotropin agonists as compared to women in the general population. A significant reduction in uterine volume was achieved in the patients with leuprolide therapy. Uterine vascular resistive indices were not altered consistently following leuprolide therapy in women with leiomyomas.

Adult↗

PubMed1998

Vitamin D and estrogen receptor allelic variants in Italian postmenopausal women: evidence of multiple gene contribution to bone mineral density.

Bone mass and bone turnover are under genetic control. Restriction fragment length polymorphisms (RFLPs) at the vitamin D receptor (VDR) gene locus have been recently correlated to bone mineral density (BMD) and rate of bone loss. However, agreement on this relationship is not universal. The existence of ethnical and environmental differences between populations, a health-based selection bias in several previous studies, and the involvement of other genes could explain these discordant findings. In this study, we examined the relationship of VDR and estrogen receptor (ER) gene RFLPs with lumbar spine and upper femur BMD in 426 Italian postmenopausal women, 57.7 +/- 0.4 yr old (144 normal, 106 osteopenic, and 176 osteoporotic). VDR gene RFLPs for ApaI, Bsm I, and TaqI restriction endonucleases and ER RFLPs for PvuII and XbaI restriction endonucleases were assessed by Southern blotting analysis and were indicated, respectively, as A-a, B-b, T-t, P-p, and X-x (uppercase letters signifying the absence and lowercase letters the presence of the restriction site). After correcting for potential confounding factors (age, height, weight, age since menopause, osteophytosis, and facet joint osteoarthritis), a statistically significant VDR genotype effect on lumbar BMD (P = 0.01, analysis of covariance), but not on femoral BMD, was detected, with subjects in AABBtt genotype showing a 13% lower BMD than those with aabbTT genotype (P < 0.05, Tukey's test). Moreover, a statistically significant prevalence of AABBtt genotype in osteoporotics, and of AabbTT and aabbTT genotypes in nonosteoporotics, were detected. Conversely, there was no significant relationship of ER genotype to either lumbar or femoral BMD, even though a trend for higher BMD values in women with the ER PP genotype (with respect to those with ER pp genotype) was detected. When mean lumbar BMD was calculated for women grouped by ER and VDR genotype, we observed a significant difference between those within the 2 opposite associations AABBtt-PPXX and aabbTT-ppxx (0.71 +/- 0.05 vs. 0.97 +/- 0.03 g/cm2, P < 0.05 Tukey's test). These results are consistent with a segregation of the VDR AABBtt genotype with a higher risk of developing osteoporosis, in the Italian female population. The introduction of another variable, the ER genotype, in the analysis of VDR genetic determination of BMD, may represent a useful model in the identification of patients at risk of developing a multigenic disorder like osteoporosis.

Alleles↗

PubMed1996

Relationship between baseline insulin-like growth factor-I (IGF-I) and femoral bone density in women aged over 70 years: potential implications for the prevention of age-related bone loss.

OBJECTIVE: To test the hypothesis that the decline in femoral bone mass associated with healthy aging is partially accounted for by deficiency of the growth hormone-insulin-like growth factor-I (IGF-I) axis. DESIGN: Cross-sectional study. STUDY PARTICIPANTS: A sample of 245 community-dwelling healthy women aged 70 and older. Exclusion criteria were diseases or medications known to affect the musculoskeletal system or the somatotrophic axis. MEASUREMENTS: Serum levels of IGF-I, calcitriol, and osteocalcin were determined by radioimmunoassay; serum calcidiol was measured by competitive binding assay, and serum parathyroid hormone (PTH) was assessed immunochemically. Urinary pyridinium crosslinks were measured by fluorescent detection after high-pressure liquid chromatography. Isometric and isokinetic quadriceps strength was evaluated using an isokinetic dynamometer. Bone density (BMD) was assessed by dual-energy X-ray absorptiometry at the proximal femur. Multiple regression was used to adjust for potential confounders. RESULTS: At the proximal femur, BMD declined by 0.59-0.84% per year. In addition to body mass index and muscle strength, serum IGF-I was found to be an independent predictor of BMD at all femoral sites. CONCLUSION: The data support the hypothesis that circulating IGF-I not only reflects the integrated growth hormone secretion but also has a direct role in the endocrine regulation of bone remodeling. The present findings support the need for further studies to assess the potential of IGF-I in attenuating age-related femoral bone loss.

Age Factors↗

PubMed2005

Normalization of bone density in a previously amenorrheic runner with osteoporosis.

PURPOSE: To examine changes in bone mineral density (BMD) and bone mineral content (BMC) in relation to pharmacological and nutritional interventions in a distance runner diagnosed with the female athlete triad of disordered eating, amenorrhea, and osteoporosis. METHODS: BMD of the lumbar spine (L2-L4) and total proximal femur were measured from ages 22.9 to 30.8 yr using dual x-ray absorptiometry (DXA). RESULTS: At age 22.9, the patient presented with primary amenorrhea, low body weight (BMI: 15.8 kg.m(-2)), and low BMD in the spine (74% of normal, T score: -2.50) and hip (80% of normal, T score: -1.54). For the next 2 yr, the patient took oral contraceptives to induce menses, but continued to maintain a low weight. Her BMD remained unchanged. At age 25.1 yr, she decided to gain weight and improve her nutrition, resulting in small increases in spinal BMD (+1.1%), hip BMD (+1.6%), and total body BMC (+7.6%) in 4 months. From ages 25.4 to 30.8 yr, the patient continued to gain weight, eventually reaching a healthy BMI of 21.3 kg.m(-2); correspondingly, since baseline, her BMD had increased 25.5% in the spine and 19.5% in the hip, bringing her BMD to within normal values (spine: 94% of normal, hip: 96% of normal). CONCLUSION: This case illustrates that even if skeletal development is interrupted in adolescence, there is still the potential for "catch-up" in BMD well into the third decade of life. Reversal of large bone density deficits in this patient can be attributed to improved nutrition and weight gain but not to hormone replacement.

Absorptiometry, Photon↗

PubMed2006

Influence of the interimplant distance on crestal bone resorption and bone density: a histomorphometric study in dogs.

BACKGROUND: The position of gingival soft tissues depends on the position and health of the underlying alveolar bone. The aim of this study was to evaluate the influence of different interimplant distances on crestal bone resorption after prosthetic restoration with a 5-mm distance between the contact point and the bone crest. METHODS: The mandibular bilateral premolars of six dogs were extracted and, after 12 weeks, each dog received eight implants, totaling 48 implants in the experiment. Two pairs, one in each hemiarch, were separated by 2 mm (group 1) and two by 3 mm (group 2). After 12 weeks, the implants received temporary acrylic prostheses. After 4 more weeks, metallic crowns substituted the temporary prostheses. After 4 more weeks, the animals were sacrificed, and their hemimandibles were removed, dissected, and processed. RESULTS: For groups 1 and 2, respectively, the mean of interimplant bone resorption (IIBR) analyzed histologically was 2.03 and 1.98 mm (P >or=0.05), and the mean of the distal extension bone resorption was 2.04 and 1.92 mm for groups 1 and 2, respectively (P >or=0.05). The crestal bone resorption between the implants was 0.13 mm (P >or=0.05) for both groups. The mean of IIBD for groups 1 and 2 was 79% and 80%, respectively. When the IIBD was compared to the distal extension bone density for group 1 (79% and 64%) and group 2 (80% and 62%), statistically significant differences were obtained for both groups (P <or=0.05). CONCLUSIONS: The distances of 2 and 3 mm between implants do not result in statistically significant differences in crestal bone resorption around implant surfaces in dogs. The bone density is enhanced when loading is present at the interimplant area.

Alveolar Bone Loss↗

PubMed1994

[Bone density and osteoporosis. An opinion].

Osteoporosis is a serious health problem for women over 45 years of age. It is divided in type I, affecting mainly cancellous bone and type II, affecting cancellous and cortical bone. Type I osteoporosis is related mainly with menopause, meanwhile, type II osteoporosis is related with ageing in both sexes. Osteoporosis has a major impact in the quality of life and the independence of the individuals, being the best treatment its prevention. All women at the beginning of the menopause should receive hormonal replacement treatment and calcium, in order to avoid type I osteoporosis, since treatment for women with established osteoporosis is aimed to halt the process of bone loss. Bone density may be measured in a reliable way by different techniques, allowing to the practitioner an accurate and reproducible measurement in different segments of the body. The main indications for bone densitometry suggested by the NOF are commented, as well as, the variability that may occur in different populations and the concept of normal values of bone density.

Adult↗

PubMed1989

Colles' fracture and bone density of the ultradistal radius.

To determine whether Colles' fracture, generally considered a manifestation of postmenopausal osteoporosis, is associated with a decrease in bone density at the site of fracture, we measured bone mineral density of the ultradistal radius (UDR-BMD) by single-photon absorptiometry with computer-assisted image processing. In 119 normal women (ages 22-92 years), UDR-BMD decreased by 17% between ages 30 and 75 years. From UDR-BMD measurements in these normal women and in 40 women (ages 53-80 years) with Colles' fracture alone, a population-based analysis was made to estimate fracture risk at different values of UDR-BMD. Colles' fracture was uncommon at UDR-BMD greater than 0.40 g/cm2 (the "fracture threshold"). As bone density decreased below this level, fractures became more frequent (a "gradient of risk").

Adult↗

PubMed2006

Distance of walking in childhood and femoral bone density in perimenopausal women.

Kuopio osteoporosis risk factor and prevention (OSTPRE) study is a population-based study from Eastern Finland. At baseline in 1989-91, bone densitometry of lumbar spine and femoral neck as assessed by DXA was carried out on women aged 48-58 (n = 3,222). In 1993, menarcheal age and health habits during adolescence were inquired from a postal inquiry. In 1996, a random sample of 254 women who had been premenopausal at baseline was interviewed over phone. They were asked how many kilometers per day they had walked to school and back, in each grade of primary school. The study sample (N = 185) was formed by excluding women with menarcheal age of >14 or <11 years. Women with any reported HRT history were also excluded. The mean age of the study sample was 50.7 (1.63) years, weight 70.8 (13.1) kg, height 161.5 (5.0) cm, and mean walking distance to and fro from the school at ages from 9 to 11 years was 2.7 (1.7) km. In regression analysis, the walking distance was associated with femoral BMD (r = 0.18, P = 0.015). After adjusting for baseline age, weight and height, this association persisted (P = 0.025). When walking distance was categorized as I = 0-0.549 km, II = 0.55-1.99 km, III = 2.0-4.99 and IV = 5.0 km and more, the respective means for femoral BMDs were 0.92, 0.97, 0.98 and 1.01 g/cm(2). Statistical significance persisted after adjusting for height, weight, age, grip strength, calcium intake, smoking, place of residence, use of contraceptive pills, physical load of work and baseline physical activity (P = 0.032). A 10 year follow-up revealed no changes in bone loss rate between the groups and femoral BMD benefits persisted (repeated measures analysis = NS). Walking distance was not associated with spinal bone density. Even though walking is a low impact activity, walking before menarche may have a moderate but long-lasting positive effect on femoral peak bone density. Lack of walking and similar low impact physical activities during peak growth years may have a negative effect on peak bone mass formation.

Aging↗

PubMed1983

Age changes in the bone density and structure of the lumbar vertebral column.

Old age is associated with a decline in bone density in lumbar vertebral bodies in both sexes, although the rate and amount of the decline is greatest in females. The bone translucency index method, described in this study, is a sensitive method of estimating bone density. The primary reason for this decline is the significant decrease in the number of transverse trabeculae of lumbar vertebrae in old age. It is postulated that the increase in vertebral end plate concavity and the increased horizontal dimensions of lumbar vertebral bodies in old age follows as a direct consequence of the selective loss of the transverse trabeculae.

Adult↗

PubMed1991

Inherited diseases of bone density in children.

In this article the radiographic manifestations of various genetic diseases predominately affecting bone mineralization are considered. Osteogenesis imperfecta and other diseases of diffuse osteopenia, hereditary rickets and rachiticlike conditions, and osteopetrosis and other diseases of increased bone density are emphasized. Recognition of the radiographic manifestations allows accurate diagnosis, therapeutic intervention when possible, and determination of recurrence risk for genetic counseling.

Bone Density↗

PubMed1989

Precise measurement of vertebral bone density using computed tomography without the use of an external reference phantom.

Bone density measurement by quantitative computed tomography (QCT) commonly uses an external reference phantom to decrease scan-to-scan and scanner-to-scanner variability. However, the peripheral location of these phantoms and other phantom variables is also responsible for a measurable degradation in accuracy and precision. Due to non-uniform artifacts such as beam hardening, scatter, and volume averaging, the ideal reference phantom should be as close to the target tissue as possible. This investigation developed and tested a computer program that uses paraspinal muscle and fat tissue as internal reference standards in an effort to eliminate the need for an external phantom. Because of their proximity, these internal reference tissues can be assumed to reflect more accurately the local changes in the x-ray spectra and scatter distribution at the target tissue. A user interactive computerized histogram plotting technique enabled the derivation of reproducible CT numbers for muscle, fat, and trabecular bone. Preliminary results indicate that the use of internal reference tissues with the histogram technique may improve reproducibility of scan-to-scan measurements as well as inter-scanner precision. Reproducibility studies on 165 images with intentional region-of-interest (ROI) mispositioning of 1.5, 2.5, or 3.5 mm yielded a precision of better than 1% for normals and 1% to 2% for osteoporotic patients--a twofold improvement over the precision from similar tests using the standard technique with an external reference phantom. Such improvements in precision are essential for QCT to be clinically useful as a noninvasive modality for measurement of the very small annual changes in bone mineral density.

Bone Density↗

PubMed1992

Comparative effects of nitrendipine and hydrochlorothiazide on calciotropic hormones and bone density in hypertensive patients.

The effects of the calcium antagonist nitrendipine and the diuretic hydrochlorothiazide on plasma calciotropic hormone concentrations and lumbar bone density were compared during the treatment of hypertension in a randomized, double-blind, 8 week parallel study, followed by a 52 week open label study. There were 32 subjects with stable essential hypertension (sitting diastolic blood pressure > or = 95 mm Hg and < or = 115 mm Hg without medication) without evidence of renal insufficiency or active heart disease. They were randomly assigned to receive either 10 mg nitrendipine twice daily or 50 mg hydrochlorothiazide daily. In order to reach and maintain target blood pressure (diastolic blood pressure < or = 95 mm Hg) during the open label period, the nitrendipine dose was titrated up to 30 mg twice daily, and additional antihypertensive drugs, of differing classes, were added as necessary. Blood samples were analyzed for concentrations of calcium, parathyroid hormone, and calcitonin, and lumbar bone density was determined by dual photon absorptiometry, at the baseline and at 24 and 52 weeks of antihypertensive drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗