Biomedical subjects

A Gotfredsen

Publications and source records attributed to A Gotfredsen.

At least 55 records · Page 3Linked to original sources

PubMed1986

Representativity of regional to total bone mineral in healthy subjects and 'anticonvulsive treated' epileptic patients. Measurements by single and dual photon absorptiometry.

Dual photon (153Gd) and single photon (125I) absorptiometry were used to measure the regional bone mineral content (BMC) and density (BMD), as well as the total body mineral content (TBBM) and density (TBBD), in sixty-nine healthy subjects and in twenty-three epileptics on phenobarbitone. The BMCs (and BMDs) of all regions were significantly correlated to each other and to the TBBM (and TBBD). No difference in the ability to discriminate between the different study groups was found for the various regions, excepting the BMD of the head. The relationship between the forearm BMC and TBBM was highly significant, and identical in the five groups. The relationships between spinal BMC and forearm BMC, and TBBM differed in the five groups. It is concluded that some local measurement may be used as estimates of the total body bone mineral in some groups of patients with minor metabolic bone disease and healthy subjects.

Adolescent↗

PubMed1986

Bone turnover in healthy adults measured by whole body retention and urinary excretion of 99mTc-MDP. Normalization by bone mass.

Whole body retention (WBR) and urinary excretion (UE) of 99mTc-diphosphonate, two complementary methods of measuring the total bone turnover, were performed in 161 normal subjects, 82 women and 79 men, aged 20-70 years. Both WBR and UE were a function of age in the women, whereas there were no age-dependent differences in the men. Between the women and men in identical age groups, the differences did not reach significance. Total body bone mineral (TBBM) was measured by dual photon absorptiometry (DPA) in all subjects. This was done in order to obtain expressions for bone turnover per bone mass as a function of age and sex. This correction emphasized the general picture seen in the raw WBR and UE data: bone turnover was constant in the men throughout life and in the women before the menopause, and only moderate differences were found between the sexes before the age of 50. After this age the mean female values increased sharply. It is noteworthy that none of the postmenopausal subjects showed low turnover values. Our data clearly demonstrate that an increase in bone turnover is part of the pathophysiology of the well-known bone loss in postmenopausal women.

Adult↗

PubMed1986

Total and local bone mass before and after normalization for indices of bone and body size.

Both single and dual photon absorptiometry are excellent techniques for longitudinal studies, owing to their high precision. Because of large biological variations they are less suited for diagnosing bone disease in single subjects. In a homogeneous group of 161 women, bone mass in the distal forearm, spine, and whole body measured by photon absorptiometry was significantly related to various general indices of body size (r = 0.29-0.59). Normalization procedures for variations of these variables could only reduce the individual variation by 10-20%. Local indices of body size (i.e. bone width or scan area) were no better in the forearm or spine. Normalization for the projected skeletal area of the whole body could reduce the SD of the total body bone mineral (TBBM) from 322 to 126 grams (15-6%). This might imply that the normalized TBBM can be used for diagnostic purposes.

Body Constitution↗

PubMed1986

Total and local bone mineral during estrogen treatment: a placebo controlled trial.

103 healthy postmenopausal women with a natural menopause 0.5-2 years previously were randomized to either estrogen (n = 52) or placebo (n = 51) treatment. Total body bone mineral (TBBM) was measured by dual photon absorptiometry and forearm bone mineral content (BMC) by single photon absorptiometry before and after one year. Both TBBM and forearm BMC fell significantly (P less than 0.001) in the placebo group, but were unchanged after estrogen treatment. The loss of bone mineral in the placebo group during one year was 5% (TBBM) and 3% (forearm BMC). A significant correlation (r = 0.53; P less than 0.001) was found between the fractional percent change in forearm BMC and TBBM. It is concluded, that both the forearm BMC and the TBBM measurements are suitable for following changes in bone mass postmenopausally. The almost equal relative amount of cortical bone in the total skeleton and in the forearm BMC may explain that longitudinally performed forearm BMC measurements are indicative of average changes in the total skeletal status.

Bone and Bones↗

PubMed1986

Biochemical markers of bone turnover in rheumatoid arthritis. Relation to anti-inflammatory treatment, sex, and menopause.

Bone turnover was determined in 125 patients with rheumatoid arthritis (RA). Bone Gla protein (BGP) and alkaline phosphatase (AP) were used as markers of bone formation. Fasting urinary calcium relative to creatinine (FU Ca/Cr) and fasting urinary hydroxyproline relative to creatinine (FU Hpr/Cr) were used as markers of bone resorption. These variables were compared to the values of two groups of normal controls in order to elucidate the pathophysiology of the osteopenia occurring in patients with RA. When the patients were divided into groups according to treatment (gold salts, penicillamine, or glucocorticoids), serum AP was highly significantly increased in all three groups, whereas serum BGP was below the normal mean. FU Ca/Cr and FU Hpr/Cr were moderately decreased in the groups treated with gold salts or penicillamine, but increased in the glucocorticoid-treated group. When divided according to sex and menopausal state and glucocorticoid treatment versus non-glucocorticoid treatment, there was a balance between bone formation and bone resorption parameters in all groups, except glucocorticoid-treated men and premenopausal women who had increased values of bone resorption parameters.

Adult↗

PubMed1986

Iliac crest biopsy: an investigation on certain aspects of precision and accuracy.

We investigated the intraobserver and section to section variation in static and dynamic histomorphometric variables in ten iliac crest biopsies. We also did a comparative study of iliac crest and lumbar spine specimens from 14 cadavers. The ten patients had osteoporosis (spinal crush fractures) and the 14 specimens taken at the necropsies were either normal or osteopenic, without malignant bone disease, bone metastases or metabolic bone disease. The majority of the coefficients of variation (CV%) were between 5 and 15% in the intraobserver analysis and 10 and 30% in the section to section analysis. These results suggest that more sections from each biopsy should be investigated to increase the precision. The correlation of variables from the iliac crest and spine showed poor agreement between resorption and osteoid variables. This fact, combined with a rather low precision of bone dynamic variables in the section to section investigation, raises the question of whether iliac crest biopsy is representative for trabecular bone turnover in the skeleton.

Aged↗

PubMed1985

The effect of glucocorticoids on bone mass in rheumatoid arthritis patients. Influence of menopausal state.

We studied 97 patients with definite or classic rheumatoid arthritis (RA). Fifty-four patients (19 premenopausal women, 25 postmenopausal women, and 10 men) had been treated with low-dose glucocorticoids for at least 12 months (mean dose less than 10 mg/day). The remaining 43 patients (15 premenopausal women, 17 postmenopausal women, and 11 men) had been treated with penicillamine, and served as a patient control group. The distal forearm bone mineral content (BMC) was measured in all patients by single photon absorptiometry using 125I, and the total body bone mineral (TBBM) was measured in 61 patients by dual photon absorptiometry using 153Gd. Compared with normal controls, both treatment groups had significantly decreased BMC and TBBM (0.01 less than P less than 0.001). When the patients were stratified according to pre- and postmenopausal state, we found significantly lower BMC and TBBM values in the premenopausal glucocorticoid-treated women than in penicillamine-treated women. However, no differences in BMC and TBBM values were found in the corresponding postmenopausal groups. In the premenopausal women treated with glucocorticoids, the duration of treatment and cumulative dose correlated with BMC. No such correlations were found in the postmenopausal women. We conclude that 1) RA is associated with loss of bone mass, 2) systemic glucocorticoid treatment further aggravates the bone loss, 3) in postmenopausal RA patients, the bone loss resulting from menopause and from the disease itself is not accelerated by low-dose glucocorticoids, and 4) in premenopausal RA patients, however, the bone mass is significantly affected by glucocorticoid treatment. We therefore suggest that these factors be considered when prescribing glucocorticoids, in order to minimize the bone loss.

Adult↗

PubMed1985

Different actions of vitamin D2 and D3 on bone metabolism in patients treated with phenobarbitone/phenytoin.

In 22 epileptic outpatients treated for at least 1 year with phenobarbitone/phenytoin the local and total bone mass, together with serum and urinary indices of calcium metabolism, were measured before and during treatment with either vitamin D2 or D3, 4,000 IU daily for 24 weeks. The results showed a distinct difference in the action of the two vitamins on bone metabolism during anti-convulsant treatment. The bone mass increased during treatment with vitamin D2, whereas the vitamin D3-treated patients showed unchanged values of bone mass, but an increased excretion rate of calcium, probably caused by increased intestinal calcium absorption. The data demonstrate that vitamins D2 and D3 (or their metabolites) have quantitative different effects in patients treated with phenobarbitone/phenytoin.

Adult↗

PubMed1985

Are disease duration and degree of functional impairment determinants of bone loss in rheumatoid arthritis?

One hundred and five patients with rheumatoid arthritis treated with a variety of antirheumatic drugs, excepting glucocorticoids, were stratified according to the degree of functional impairment (functional classes I to IV) and duration of the disease (0-3 years; 4-8 years; and greater than 8 years). The variables investigated were distal forearm bone mineral content (BMC), biochemical markers of bone formation: serum alkaline phosphatase and serum bone gamma-carboxyglutamic acid containing protein (BGP) and biochemical markers of bone resorption: fasting urinary calcium and fasting urinary hydroxyproline. Significant relationships were found between BMC and functional impairment and duration of the disease. Indices of bone formation and bone resorption rose with increasing functional impairment, particularly those of bone resorption. It is concluded that disability induces osteopenia in rheumatoid arthritis by increasing the bone turnover with a more marked increased in resorption than in the formation processes. The effect of the disease duration is merely that of adding more years of functional impairment.

1-Carboxyglutamic Acid↗

PubMed1985

Comparison of single- and dual-photon absorptiometry in postmenopausal bone mineral loss.

We describe a single photon absorptiometric (SPA) technique, which enables differential estimation of the rates of loss from trabecular and cortical bone. Ten scans are obtained in the forearm: six in an area with about 7% trabecular bone and four scans in the adjacent distal area with a trabecular bone content of 25%. By comparing bone masses of these two sites in 19 postmenopausal and 53 premenopausal women, the postmenopausal trabecular bone loss was estimated to be approximately seven times greater than cortical loss within the first years of cessation of regular vaginal bleeding. On a group basis the bone loss at the distal forearm scan site (by SPA) corresponded closely to the spinal bone loss (by dual-photon absorptiometry). The reproducibility of the two scan sites in the forearm was 1-1.5% (CV%), which makes the method suitable for longitudinal studies. Corrections for variations in fatty tissue covering can be made without deterioration of the reproducibility. The high precision can only be achieved with a good calibration procedure; if calibration is not done the reproducibility error increases two- or threefold.

Adult↗

PubMed1984

The effect of tamoxifen on bone mineral content in premenopausal women with breast cancer.

Thirty-one of 62 consecutive premenopausal women with primary cancer of the breast completed a 1-year investigation period, receiving either 30 mg tamoxifen daily (15 patients) or placebo (16 patients). They were examined at the operation (t0) and at 3-month intervals (t1, t2, t3, and t4). Bone mineral content (BMC) was measured at operation and after 12 months. Fifty-six patients with benign tumors were included as healthy controls. All values of both cancer treatment groups and of the benign tumor group were comparable at the time of operation. BMC decreased significantly in both cancer patient groups when 12-month values were compared to the initial level (tamoxifen, -3.2%, P less than 0.001 and placebo -2.5%, P less than 0.01). However, no significant difference in BMC changes was noted between tamoxifen and placebo treatment. The serum phosphate was significantly decreased in the tamoxifen treatment group at each examination. In the placebo group, the alkaline phosphatase level increased significantly at each examination, whereas the serum magnesium fell at the 6- and 12-month examinations. All other biochemical indices of calcium metabolism were basically unchanged. It is concluded that BMC is reduced in metastatic breast cancer through osteolytic metastatic bone foci. Tamoxifen also decreases the BMC. It is, however, unclear if this effect is due to a progression of the disease in spite of the treatment or if it is caused by a direct action of tamoxifen on bone.

Adult↗

PubMed1984

Relationship between local and total bone mineral in normal pubertal boys.

The bone mineral content of the distal forearm (BMC) using single-photon absorptiometry and total body bone mineral (TBBM) using dual-photon absorptiometry were determined in 19 normal boys at different pubertal stages. A highly significant correlation between BMC and TBBM was seen (r = 0.78, P less than 0.001) with a standard error of estimate (SEE) of 13%. Subgroups of early and late pubertal stages did not show any significant differences in the regression lines indicating an identical relationship between BMC and TBBM at various stages of pubertal development although great changes in bone mineral content take place. Due to high accuracy and reproducibility of both methods, which are non-invasive and harmless, measurement of BMC is suitable to estimate changes in total mineral content of the body. This may be of importance in various diseases with disturbance in growth and bone metabolism.

Adolescent↗

PubMed1984

Total body bone mineral in vivo by dual photon absorptiometry. I. Measurement procedures.

A dual photon scanner using a 1 Ci 153Gd source, a NaI detector, traditional electronics and a desktop computer, was constructed. Software for the computation of the total body bone mineral (TBBM) was developed. Non-linear influences such as deadtime due to high count rates, patient scatter and Compton effects were investigated and correction algorithms were introduced in order to obtain exponential attenuation. System precision was measured on a bone-aluminium standard (CV = 2.6%) and system linearity was assessed on aluminium pieces (r = 0.999, SEE = 3.0%). Short-term precision in vivo was tested on 15 healthy subjects scanned twice with a 2-month interval (CV = 2.4%). Long-term reproducibility in vivo was tested on two healthy subjects scanned eight times with 1-month intervals (CV = 1.9% and 3.2%). The influence of patient orientation was investigated on two skeletons. No significant difference was found between anatomical and random orientation. It was concluded that the precision errors were small, therefore making the method applicable not only in cross-sectional studies but also in longitudinal studies designed to investigate the loss or gain of total bone mass in patients suffering from calcium metabolic disorders.

Bone and Bones↗

PubMed1984

Total body bone mineral in vivo by dual photon absorptiometry. II. Accuracy.

We investigated the accuracy of total body mineral (TBBM) measured by dual photon absorptiometry (1 Ci 153Gd source, 44 and 100 KeV) using skeletons, soft tissue equivalent materials and whole cadaver extremities. The accuracy was assessed on five skeletons (r = 0.99, SEE = 1.5%). The influence of the soft tissue composition on the TBBM measurement was investigated in the same five skeletons. They were scanned in a 16 cm thickness of ethanol solutions of different concentration (0, 20, 40, 60, 80, 100% ethanol) and only a 2% difference (non-significant) was found between measuring 100% ethanol and 100% water. Furthermore, seven whole cadaver extremities were scanned before and after removal of the soft tissues (r = 0.995, SEE = 6.3%). The slope was not different from one and the intercept not different from zero. Equipment at the University of Wisconsin, Madison, and at Glostrup Hospital, Denmark, was compared by measuring the same healthy subjects and skeletons on both scanners. The Glostrup and Madison TBBM values correlated well (r = 0.99, SEE = 5.8%) and the intercept (345 Glostrup arbitrary units) was not significantly different from zero (P greater than 0.05). The TBBM results were calibrated into total body calcium (TBCa) and no significant difference was found between Glostrup and Madison TBCa values (P greater than 0.20).

Bone and Bones↗

PubMed1984

Relationship between local and total bone mineral content after gastric surgery.

We compared the total body bone mineral mass (TBBM), assessed by the dual-photon technique, with the local bone mineral mass (BMC), measured by single-photon absorptiometry, in 27 ulcus patients treated by either gastric resection or parietal cell vagotomy. Except for raised concentrations of serum alkaline phosphatase in the Billroth I resection group, the biochemical findings and the measurements of bone mass (local and total) were normal. A highly significant correlation between local and total body bone mineral mass was found in both patients (r = 0.84) and controls (r = 0.91). Since the relationship between these two measurements is identical in the patient population and in the age-matched control group, it is concluded that the local BMC may be useful to estimate total bone mass after gastric surgery.

Aged↗

PubMed1983

Relationship between local and total bone mineral in patients with rheumatoid arthritis and normal subjects.

Total body bone mineral (TBBM) measured by dual photon absorptiometry and local bone mineral (BMC) measured by single photon absorptiometry were determined in 55 patients with definite or classical rheumatoid arthritis. All of them had been on a steady dose of anti-inflammatory drugs for at least 12 months, and furthermore, 13 patients were on glucocorticoids. The results were compared with 49 normal persons matched for sex, age and menopausal state. A highly significant correlation was found between BMC and TBBM in the patients (r = 0.84, SEE = 13.0%) as well as in the controls (r = 0.77, SEE 10.5%). Moreover, the intercepts and the slopes were virtually of the same order. Subdividing the patients according to glucocorticoid treatment the same high correlations were shown in the two subgroups. As a group the patients on glucocorticoids had a highly significant generalized osteopenia (a reduction of TBBM of 26% compared to normals). The patients on other anti-inflammatory drugs had a significant, but less pronounced generalized osteopenia (a reduction of TBBM by 11% compared to normals). It is concluded, that BMC of the forearm can be used as a valid estimate of total body calcium in groups of patients with rheumatoid arthritis and in normal subjects.

Activation Analysis↗

PubMed1983

Effect of natural oestrogen/gestagen therapy on uric acid metabolism in post-menopausal women.

Uric acid metabolism was studied in groups of early post-menopausal women before and during long-term administration of natural oestrogen/gestagen (n = 21), bendroflumethiazide (n = 19) or placebo (n = 34). Serum uric acid rose definitely, by 13.0% during thiazide, and decreased slightly, by 4.9%, during hormone treatment. The latter deviation did not differ significantly from that of -2.9% seen in the placebo group. The urinary excretion rates of uric acid observed during thiazide and hormone treatment did not differ significantly from that of the placebo group. It is concluded, that within the present design of study, which readily permits detection of the well-known hyperuricaemic action of thiazide, oestrogen/gestagen hardly affects uric acid metabolism.

Adult↗

PubMed1983

Relationship between local and total body bone mineral in epileptic patients and normal subjects.

Total body bone mineral (TBBM), measured by dual photon absorptiometry, and local body bone mineral content (BMC), measured by single photon absorptiometry, in both forearms were determined in 49 epileptic patients, 19 receiving phenytoin and 30 receiving carbamazepine, and in 55 controls. A highly significant correlation was found between BMC and TBBM in the patients (r = 0.81, SEE = 10.6%), as well as in the controls (r = 0.78, SEE = 9.9%). Furthermore, the intercepts and the slopes were virtually of the same order. The patients on phenytoin had a mild generalised osteomalacia, independent of method used, whereas the patients on carbamazepine did not have this side-effect. It is concluded that BMC of the forearm can be used as a valid estimate of total body bone mineral in groups of epileptic patients and in normal subjects.

Adult↗