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PubMed1995

Combined treatment of growth hormone and the bisphosphonate pamidronate, versus treatment with GH alone, in GH-deficient adults: the effects on renal phosphate handling, bone turnover and bone mineral mass.

OBJECTIVE: A potential drawback of GH replacement therapy in GH deficient (GHD) patients is the initial decrease in bone mass. The present study investigates the effects of the addition of pamidronate to GH replacement therapy in adult GHD subjects, on serum PTH and 1,25-dihydroxyvitamin D3 (1.25-(OH)2D3) levels, renal phosphate handling, bone turnover and bone mineral content (BMC). DESIGN: Six GHD adult patients were studied for two periods of 6 months with a wash-out period of 3 years. In the first period they were treated with conventional replacement therapy and GH. In the second study period GH treatment was identical, while after 2 weeks 150 mg pamidronate per day was added. RESULTS: In the first study period (GH only) there was a significant increase of phosphate reabsorption, without a change in serum PTH and 1.25-(OH)2D3 levels. This suggests a specific effect of GH or IGF-I on renal phosphate handling. This was supported by the close correlation between serum IGF-I levels and TmP/GFR (r = 0.75, P < 0.0001). When GH was administered together with pamidronate, this correlation was less, but remained significant (r = 0.44, P < 0.001). The increase in bone turnover and decrease in BMC, as initially observed during GH replacement therapy alone, were attenuated by simultaneous pamidronate administration. The decline in lumbar spine BMC (measured with dual-photon absorptiometry) at 6 months was -3.1 +/- 1.5% during GH replacement therapy alone vs an increase of +3.8 +/- 2.0% during the administration of the combination of GH and pamidronate (measured with dual-energy X-ray absorptiometry). At the distal and proximal forearm the changes amounted to -0.5 +/- 3.4% vs +4.5 +/- 1.8% and -1 +/- 1.2% vs +1.2 +/- 1.1% respectively. CONCLUSIONS: This study shows that the addition of a bisphosphonate to GH replacement therapy in GHD adults counteracts the GH (or IGF-I) induced increase in renal phosphate reabsorption. Furthermore, it reduces GH induced bone turnover and prevents the initial decrease in bone mineral content seen during GH treatment alone, resulting in a beneficial effect on bone mineral mass. Pamidronate might therefore be an important adjunct to GH replacement therapy in adults with GHD and severe osteopenia during the early phase of GH induced stimulation of bone turnover.

Absorptiometry, Photon↗

PubMed1995

Further increase in forearm cortical bone mineral content after discontinuation of growth hormone replacement.

OBJECTIVE: Growth hormone replacement of adults with childhood onset GH deficiency results in an increase in bone mineral density (BMD) after 6-12 months of GH replacement. By measuring BMD 12 months after discontinuation of GH replacement we aimed to investigate whether there is an effect of GH replacement on BMD persisting after GH has been withdrawn. DESIGN: BMD was measured 13 +/- 1 (mean +/- SE, range 11-16) months after discontinuation of GH replacement. PATIENTS: Ten adults, age 23.2 +/- 1.4 (range 18.8-32.4) years, with childhood onset isolated GH deficiency (2 idiopathic, 8 irradiation induced) who had previously completed a study of the effect of 12 months of GH replacement on BMD. MEASUREMENTS: Forearm cortical bone mineral content (BMC) was measured using single-photon absorptiometry at the proximal site of the distal forearm. Forearm integral BMC at the ultradistal site of the forearm and bone width at both proximal and ultradistal sites of the distal forearm were measured by the same technique. Vertebral trabecular BMD was measured using quantitative computed tomography. RESULTS: Forearm cortical BMC was significantly greater than that measured at the time of discontinuation of GH (1.48 +/- 0.04 vs 1.44 +/- 0.05 g/cm). There was no significant change in forearm integral BMC or in vertebral trabecular BMD after discontinuation of GH. There was no significant change in bone width at proximal and ultradistal sites of the distal forearm after discontinuation of GH. CONCLUSION: After discontinuation of GH replacement the further increase in forearm cortical bone mineral content without a significant increase in forearm bone width suggests that the increase in cortical bone mineral content is due to a persisting effect of previous GH replacement, and not to further spontaneous attainment of bone mass before peak bone mass is reached. These findings emphasize the importance of continuing to monitor bone mass after the stimulus to increase bone turnover has been withdrawn.

Absorptiometry, Photon↗

PubMed1991

Desogestrel in hormone replacement therapy: long-term effects on bone, calcium and lipid metabolism, climacteric symptoms, and bleeding.

Seventy-three healthy, postmenopausal women, aged 45-54 years, were randomly assigned to one of three groups for 2 years of treatment: 17 beta-oestradiol 1.5 mg on days 1-12 and 17 beta-oestradiol 1.5 mg + desogestrel 150 micrograms on days 13-24 (E2/DG) or oestradiol valerate 2 mg on days 1-11 and oestradiol valerate 2 mg + medroxyprogesterone acetate 10 mg on days 12-21 (E2V/MPA) or placebo. Fifty-seven women (78%) completed the study. Bone mineral content of the distal regions of the forearms (measured by single photon absorptiometry, SPA) and bone mineral density of the spine (measured by dual energy X-ray absorptiometry, DXA) showed increases of 0.5-1% and 4-5%, respectively, in the hormone groups over 2 years. The placebo group exhibited a decrease in spinal bone density of 2% per year, and in the forearm of 2.5-3.5% per year. Biochemical estimates of bone turnover (serum alkaline phosphatase and fasting urinary calcium) decreased significantly to premenopausal levels in the hormone groups but remained unchanged in the placebo group. In both hormone groups total cholesterol decreased by about 9% (P less than 0.001), whereas low density lipoprotein cholesterol decreased by 16% in the E2/DG group and 20% in the E2V/MPA group (P less than 0.001). High density lipoprotein cholesterol showed only minor, insignificant changes in the hormone groups. The placebo group had virtually unchanged values. Climacteric symptoms, including hot flushes, were significantly reduced in both hormone groups. Bleeding occurred regularly in about 80% of the women.(ABSTRACT TRUNCATED AT 250 WORDS)

Absorptiometry, Photon↗

PubMed1994

Relation between calcium intake, grip strength and bone mineral density in the forearms of girls aged 13 and 15.

OBJECTIVES: To evaluate whether there is an association between calcium intake in adolescent girls and bone mineral density (BMD). Also, the relationships between BMD, various anthropometric factors and grip strength were evaluated. DESIGN: Cross-sectional comparison of BMD, calcium intake and grip strength in 13 and 15 year age groups, randomly selected. SETTING: Ten secondary elementary schools in the Reykjavik area. SUBJECTS: One hundred and ninety-seven Icelandic Caucasian girls aged 13 and 15. One hundred and seventy participated and 162 completed the study. MAIN OUTCOME MEASURES: Single photon absorptiometry was used to measure BMD and bone mineral content (BMC) in both forearms. Consumption of milk and dairy products was assessed using a food frequency questionnaire. Height and weight were measured and grip strength was determined with a hand-held dynamometer. RESULTS: Calcium intake was found to be significantly correlated to BMD in the older group after adjustment for menarcheal age and weight (r = 0.24; P < 0.05). Division into three subgroups yielded a significantly greater coefficient of correlation between calcium intake and BMD in the lowest calcium consumption group (r = 0.44; P < 0.05). No association was found in the younger age group. Significant positive correlations between grip strength and regional bone mineral density accounted for up to 16.8% of the variation in BMD (P < 0.001) and 38.4% of the variation in BMC. CONCLUSIONS: This study is consistent with the hypothesis that a threshold effect of calcium intake on BMD might exist. Above this threshold (1000-1200 mg) no further effect on BMD was seen. The results show a strong association between grip strength, a measure representative of total body strength, and BMD.

Absorptiometry, Photon↗

PubMed1995

13-cis-retinoic acid and bone density.

BACKGROUND: 13-Cis-retinoic acid has an influence on bone in patients on long-term treatment as well as on short-term treatment. The presence of skeletal abnormalities after the treatment was established by roentgenologic and scintigraphic examinations. We wanted to know whether a 6-month course of low-dose 13-cis-retinoic acid has a clinically important influence on bone density in men with severe acne. METHODS: We examined 15 men with severe acne before and after treatment with 13-cis-retinoic acid by dual-photon absorptiometry of the lumbar spine. RESULTS: The mean increase in bone density was 3.0% (95% confidence interval 1.3-4.5), which is normal for the period from puberty to late twenties. Bone density increased in 13 of our 15 patients. CONCLUSIONS: As shown by this highly sensitive modern densitometric method, 13-cis-retinoic acid has no clinically important influence on bone density in male patients with severe acne.

Absorptiometry, Photon↗

PubMed1995

Bone mineral density in premenopausal anovulatory women.

To examine the impact of amenorrhea on bone mineral density in women of reproductive age, we performed a cross sectional study in 190 amenorrheic women, comprising 113 premature ovarian failure, 27 primary hypothalamic amenorrhea, 38 hyperprolactinemia and 12 Sheehan's syndrome. Measurement of bone mineral density was carried out using dual photon absorptiometry at four sites: femur neck, ward's triangle, trochanter and spine (L2-4) and we compared the result with that of 163 normal-cycle control women with age matched. Bone mineral densities was significantly low in patients with primary hypothalamic amenorrhea and premature ovarian failure at all four sites. In those with hyperprolactinemia a decrease in bone mineral density was noted at femur neck and spine while those with Sheehan's syndrome is associated with decreased bone density at femur neck, ward's triangle and trochanter. The degree of bone loss and the affected sites seems differ depending on the type of amenorrhea. In patients with primary hypothalamic amenorrhea, significant bone loss was already noted at all four sites by age 20. The decrement in bone density continued rapidly during the early twenties up to age 25 and then slowed after age 25. In those with premature ovarian failure with secondary amenorrhea there were no decrease in bone mineral density within the first year after onset of amenorrhea, however, in the subsequent 2 years, the reduction in BMD was rapid and thereafter the reduction slowed remarkably. The BMD in this study positively correlated with the body mass index and negatively with the phosphorus intake.

Absorptiometry, Photon↗

PubMed1992

Calcium balance, growth and skeletal mineralisation in patients with cystoplasties.

Twelve adult female patients and 16 children who had undergone augmentation cystoplasty at least 2 years previously were studied to assess calcium balance and skeletal mineralisation. The serum and 24-h urinary calcium levels were measured and arterial blood gas analysis was performed in all patients. In children, skeletal mineralisation was assessed by serial study of their growth charts, comparing their growth centiles before and after cystoplasty. In adults, skeletal mineralisation was assessed by dual photon absorptiometry (DPA). As previously reported, all patients had a metabolic acidosis, usually with respiratory compensation. Serum and 24-h urinary calcium levels were all within the normal range. Growth charts of the 6 children with colocystoplasties showed an average of 20% reduction in growth potential in 3 of them. Growth charts in the 10 children with ileocystoplasties did not show any change in growth pattern. DPA bone scans in adults were all normal. These results suggest that if calcium is mobilised from bone in patients with a cystoplasty as a result of the metabolic acidosis, then it is reabsorbed from the bladder by the gut segment after an ileocystoplasty; colonic segments are less efficient than ileal segments, however, so that after a colocystoplasty skeletal demineralisation or a reduction in growth potential is more likely.

Absorptiometry, Photon↗

PubMed1995

Peripheral osteopenia in adult patients with insulin-dependent diabetes mellitus.

Alterations in bone metabolism in diabetes mellitus is a topic of special interest. Bone blood flow is increased in the distal limb of diabetic patients, which is believed to increase osteoclastic activity. We measure bone mineral density using dual-photon absorptiometry in the distal lower limb, the femoral neck, and the lumbar spine in 41 IDDM patients and in 30 control persons. In the diabetic group there was a 10% reduction of bone mineral density in the femoral neck (p < 0.01) and a 12% reduction in the distal limb (p < 0.001) compared with the control group. No significant difference was found in the lumbar spine (p = 0.22). Our data yield incidence for peripheral osteopenia in IDDM-patients, independent of any systemic bone disease such as osteoporosis. A link between decreased bone mineral density and diabetic neuropathy has been observed for the femoral neck (p < 0.001), but not for the distal limb or axial skeleton. Whether there is a common aetiological link or a casual connection between diabetic neuropathy and bone mineral density has still to be determined.

Absorptiometry, Photon↗

PubMed1996

Multiparity and bone mass.

OBJECTIVE: To investigate the influence of multiparity on bone mass of the axial skeleton in a population of women of high parity. DESIGN: Open study of Omani women. SETTING: Medical physics department and clinical physiology department of a third degree referral (university) hospital. PARTICIPANTS: A consecutive series of 159 normal women referred with low back pain over a period of six months. RESULTS: The bone mineral density was measured with dual-photon absorptiometry and the mean was found to be 0.984 (+/-0.166) (+/- SD) g cm-2. The age ranged from 20 to 70 years with a mean age of 43.4 (+/- 12.5) years. The number of children per woman ranged from 0 to 14 with a mean of 5.1 (+/- 3.5). There was no statistically significant influence of the number of children per woman on bone mineral density but there was a strong correlation with age and body size variables. CONCLUSION: Multiparity does not influence lumbar spine bone mineral density in normal women.

Absorptiometry, Photon↗

PubMed2004

Long term effects of oestrogen therapy on bone loss in postmenopausal women: a 23 year prospective study.

OBJECTIVE: To determine the long term effect of oestrogen therapy on bone loss after menopause. DESIGN: Prospective observational study over 23 years. SETTING: Malmö, Sweden. SUBJECTS: Twenty-eight women taking oestrogen and 196 women not taking oestrogen during the follow up. METHODS: Bone mineral density of the forearm was measured by single-photon absorptiometry at age 48 and 72 years. Use of oestrogen therapy was noted. MAIN OUTCOME MEASURE: Rate of forearm bone loss between the age of 48 and 72 years. RESULTS: Women taking oestrogen, for a median of 17 years (range 4 to 26), had 8.7 percentage points (95% CI 3.8-13.5) lower rate of bone loss compared with women not taking oestrogen during the same period. Each year of oestrogen therapy reduced the rate of bone loss by 0.8 percentage points (95% CI 0.2-1.4). CONCLUSIONS: The use of oestrogen seems to reduce the rate of bone loss over a period of 23 years, and the longer the duration of the therapy, the less bone loss.

Absorptiometry, Photon↗

PubMed2000

Bone mineral density and body composition in patients with ulcerative colitis.

OBJECTIVE: Reduced bone mineral density (BMD) has been reported in ulcerative colitis (UC) patients, but body composition (fat and lean mass) has never been concomitantly studied. We sought to investigate BMD and body composition in a group of UC outpatients with the following characteristics: age 18-60 yr (men) and 18-45 yr (women); no intestinal resection; no immunosuppressive treatment; and regular menstruation. METHODS: Whole body and subregional BMD and body composition in 43 UC patients (21 men, 22 women; male mean age, 36.5 [21-57] yr; female mean age, 35.3 [23-45] yr) and 121 healthy volunteers were studied by means of dual X-ray photon absorptiometry. RESULTS: There were no differences in total and subregional BMD, or fat and lean mass between the patients and controls, except that the total and trunk lean mass of the UC women was lower than that in the normal controls. No correlation was found between lifetime steroid intake and BMD. CONCLUSIONS: UC outpatients do not differ from normal subjects in terms of BMD and fat mass. Mild and moderate UC does not represent a risk factor for osteopenia.

Absorptiometry, Photon↗

PubMed1996

Long-term bone mass evaluation of mandible and lumbar spine in a group of women receiving hormone replacement therapy.

The overall aim of this study was to examine the relationship between bone mass of the jaw and the axial skeleton. Sixty-nine subjects (age at entry: 32-64), who underwent hormone replacement therapy during the study period, participated. Bone mass of the lumbar spine was determined using dual photon absorptiometry. The jaw-bone of the posterior region of the mandible was evaluated by means of standardized long-cone radiography using individual bite-blocks. A densitometric wedge in the film holder provided a reference to quantify bone mass. From both measurements, it appeared that the bone mass of the mandible and the lumbar spine showed a moderate relationship. The present results also confirmed that estrogen replacement therapy had a positive effect on the bone mass of the mandible and the lumbar spine. Different estrogen regimens resulted in different increases in bone mass during the observation period, which was on average 5 yr.

Absorptiometry, Photon↗

PubMed1998

Effects of physical exercise on bone mass, balance skill and aerobic capacity in women and men with low bone mineral density, after one year of training--a prospective study.

Vadstena is a small community in the county of Ostergötland, Sweden, where a project began in 1989 to prevent osteoporosis and to lower the expected incidence of osteoporotic fractures. Persons aged 40-70 years who had a low bone mineral density (BMD) value at screening of the distal radius by single-photon absorptiometry (SPA) were invited to participate in a training study during one year. The definition of low BMD was a densitometry value below -1 SD (standard deviation) from a sex- and age-specific reference value (z-score). Fifteen persons wanted to exercise in a group and 15 persons wanted to become a control group. All participants answered a questionnaire about lifestyle, occupation, diseases, medication and heredity. Clinical tests were made regarding mobility of the joints and muscles, balance and physical fitness. BMD for the hip and the lumbar spine were assessed by dual-energy X-ray absorptiometry (DXA) before and after the investigation period. The training programme was carried out for 60 min twice a week during one year and had the intention to improve bone mass, muscle strength and flexibility, balance skill and aerobic capacity. After the training period there was a significant increase in BMD at the greater trochanter (P < 0.01), in balance skill (standing on one leg with closed eyes and "ski step"-test) (P < 0.05) and in oxygen uptake capacity (P < 0.05) in the exercise group. In the control group, there was a significant increase in BMD at the lumbar spine (P < 0.05). However, these results should be judged with caution because several participants were over the age of 60, and at that age degenerative changes in the lumbar spine may increase to a greater or lesser extent. Regular weight-bearing exercises during one year seem to influence BMD at the greater trochanter in a training group comprising both women and men. However, our study was small in number and further training studies are needed to assess the effect of weight-bearing training on bone mass in different sex- and age-specific groups.

Absorptiometry, Photon↗

PubMed2005

Physical activity in the post-pubertal period is associated with maintenance of pre-pubertal high bone density-- a 5-year follow-up.

OBJECTIVE: To evaluate the association between physical activity (PA) and skeletal growth in girls during adolescence. DESIGN: A 5-year, observational, population-based study (Reykjavik, Iceland). SUBJECTS: Seventy-eight Caucasian girls, mean age 13.4+/-1.0 (mean+/-SD) years at baseline. METHODS: Bone mineral density (BMD, g/cm2) and bone width (cm) were measured in the forearm by single-photon absorptiometry at baseline and with dual-energy X-ray absorptiometry after 3 and 5 years, when lumbar spine, femoral neck (FN) and total body were also evaluated. Half of the physically active girls were compared with the other half of less active girls. RESULTS: BMD in physically active girls was higher in the forearm at both baseline (P=0.001) and after 5 years (P=0.04) in comparison with less active girls. BMD was higher for the total body (P=0.0001), spine L2-L4 (P=0.02) and FN (P=0.002) in the active girls at age 18. The accrual of forearm BMD and bone width from age 13 to 18 was no different when comparing the two groups. CONCLUSIONS: Pre-pubertal PA is associated with high BMD at age 13 and continued PA is associated with maintenance of high BMD until age 18.

Absorptiometry, Photon↗

PubMed1989

Bone mineral content of appropriate and light for gestational age preterm and term newborn infants.

Bone mineral content was measured by single photon absorptiometry at the right mid humerus of 122 appropriate and 35 light for gestational age newborn infants born after 26 to 42 weeks of gestation. Bone mineral content was 2.4 times greater at the mid humerus than at the distal radius. Even in extremely low birth weight infants reproducible measurements were possible at the mid humerus. Light for gestational age infants showed a lower bone mineral content than appropriate for gestational age infants when bone mineral content was related to gestational age. When related to birthweight (g) bone mineral content showed a similar linear relationship in light for gestational age (mg/cm = 44.2 + 0.037 weight) and appropriate for gestational age (mg/cm = 39.4 + 0.040 weight) infants. For all 177 infants the relationship was mg/cm = 32.3 + 0.045 weight (r = 0.91). It is concluded that in growing preterm infants bone mineral content should be assessed in relation to weight rather than to age.

Absorptiometry, Photon↗

PubMedDate not supplied

Phosphate, alkaline phosphatase and bone mineralization in preterm neonates.

We examined the relationship between bone mineralization, measured by single photon absorptiometry, and blood phosphate and alkaline phosphatase concentration in 71 preterm neonates. Although both alkaline phosphatase and phosphate concentrations were significantly related to bone mineral content, and alkaline phosphatase concentrations were related to bone mineral content relative to weight, each could only explain a small amount of the variation in bone mineralization. Hence, concentrations of neither could be used to identify those neonates with the greatest bone mineral deficits.

Absorptiometry, Photon↗

PubMed1994

Bone mineral density in the cortical and trabecular distal forearm in healthy children and adolescents.

Bone mineral density in cortical (BMDd) and trabecular parts (BMDud) of the distal forearm was studied in 494 healthy subjects ranging from 8 to 17 years with single photon absorptiometry. Mean BMDd was 6.8% higher (p < 0.0001) in boys than in girls in the < 11 years age group (n = 163). Mean BMDud was 8.2% higher (p < 0.0001) in boys than in girls in the adolescent age group (> or = 11 years, n = 331). While BMDd increased from 11 years of age in girls and was delayed by 2 years in boys, BMDud increased from 10 years of age in boys and was delayed by 1 year in girls. By multiple regression analysis, age, weight and height were variably related to bone density depending on measuring site, sex and age. At 14 years of age, postmenarcheal girls had obtained BMDud values similar to those of an adult premenopausal group. Cortical bone density in girls was very close to corresponding BMDd values of the adult premenopausal group at 16 years of age. In conclusion, this cross-sectional study indicates sex and age variability in forearm bone mineralization at trabecular and cortical sites. The substantial mineralization taking place between 11 and 16 years of age, with achievement of adult premenopausal bone density values, makes this 5-year period crucial for bone development.

Absorptiometry, Photon↗

PubMed1995

Dietary calcium, saturated fat, fiber and vitamin C as predictors of forearm cortical and trabecular bone mineral density in healthy children and adolescents.

Diet, weight-bearing physical activity (WPA) and daylight hours spent outdoors (DE) were related to bone mineral density in the distal (BMDd) and ultradistal (BMDud) forearm of 495 healthy children (8-11 years) and adolescents (11-17 years). BMD was assessed by single photon absorptiometry. Using multiple regression, BMDd was predicted by saturated fat and BMDud by fiber in children. In adolescents, BMDd was predicted by saturated fat and vitamin C, and BMDud by calcium and vitamin C. WPA and DE were not related to BMD. In conclusion, our results showed that current intake of calcium, saturated fat, fiber and vitamin C were positively associated with forearm BMD in children and adolescents. These associations depended on age and bone type. If our findings are verified, dietary recommendations, especially when aimed at young people, may have to be reconsidered.

Absorptiometry, Photon↗