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Biomedical subjects

C Hassager

Publications and source records attributed to C Hassager.

At least 109 records · Page 6Linked to original sources
PubMed1990

Dual-energy x-ray absorptiometry: a precise method of measuring bone mineral density in the lumbar spine.

We compared two methods of measuring spinal bone mineral content and density (BMC/BMD): conventional dual-photon absorptiometry (DPA) and a more recent method, dual-energy x-ray absorptiometry (DEXA). The clinical usefulness of both methods was compared in the measurement of BMC in the forearm. DEXA had a long-term in vivo precision of 1% which was significantly better than that of DPA. Changes in the distribution of fatty tissue influenced the accuracy of the two spinal methods in different ways. Forearm BMC discriminated between the bone mass of early and late postmenopausal women to the same degree as DPA and DEXA. The variability in the response to estrogen treatment and placebo was much lower with DEXA and forearm BMC than with DPA. We conclude that DEXA provides a fast and precise measurement of spinal BMC/BMD. The accuracy remains to be evaluated for in vivo studies.

Absorptiometry, Photon↗
PubMed1989

Relation of body fat distribution to serum lipids and lipoproteins in elderly women.

Fat distribution measured by dual photon absorptiometry, serum lipids and lipoproteins were determined in 95 elderly women with mild osteoporosis. Increasing obesity, determined anthropometrically as body mass index (BMI) = body weight/(height)2, was associated with a more central fat distribution (P less than 0.001) Central fat distribution correlated positively and independently of BMI and body weight to serum cholesterol, low density lipoprotein-cholesterol (LDL-C), triglycerides and the ratio LDL-C/HDL-C (P less than 0.05), whereas the correlation between central fat distribution and high density lipoprotein-cholesterol (HDL-C) was negative (P less than 0.05). We conclude that the increased risk of cardiovascular disease observed in subjects with central fat distribution might be partly mediated through changes in the lipoprotein profile.

Absorptiometry, Photon↗
PubMed1989

Changes in soft tissue body composition and plasma lipid metabolism during nandrolone decanoate therapy in postmenopausal osteoporotic women.

Thirty-nine osteoporotic (prior spine or Colles' fracture) but otherwise healthy postmenopausal women were allocated to receive blindly either 50 mg nandrolone decanoate (ND) intramuscularly or placebo injections every 3 weeks for 1 year. Thirty-six women (92%) completed the study. ND treatment resulted in an increase in non-osseous lean weight and a corresponding decrease in fat mass (measured by dual photon absorptiometry). A 20% increase in the 24-hour urinary creatinine excretion indicated that the increase in non-osseous lean weight was caused mainly by an increase in muscle mass. With regard to serum lipids and lipoproteins, ND treatment slightly decreased high density lipoprotein (HDL) cholesterol without significantly affecting total cholesterol, low density lipoprotein (LDL) cholesterol or triglycerides. In conclusion, treatment with ND changes the soft tissue composition in osteoporotic postmenopausal women towards a leaner and more muscular body.

Adipose Tissue↗
PubMed1989

Estrogen/gestagen therapy changes soft tissue body composition in postmenopausal women.

The long-term effect of percutaneous and oral estrogen replacement therapy on soft tissue body composition was examined in a two-year, placebo-controlled study with 110 early postmenopausal women. The women were allocated to four treatment groups: (1) oral cyclical combination of estradiol valerate and cyproterone acetate, (2) oral placebo, (3) percutaneous 17 beta-estradiol, supplemented by oral progesterone during the second year, or (4) percutaneous placebo cream. Total-body lean body mass (LBM) and fat mass (FM) were measured by dual photon (153Gd) absorptiometry once a year, and the fat layer in the distal forearm (FATarm) was measured every 3 months by single photon (125I) absorptiometry. Both hormone therapies prevented an increase in FATarm, as observed in the placebo groups. A similar pattern was seen for FM, body weight, and skin-fold thickness (measured once a year by mechanical calipers), whereas LBM was unaffected by the therapy. Hormonal replacement therapy prevents the age-related increase in body fat observed after the menopause.

Adipose Tissue↗
PubMed1989

Measurement of the subcutaneous fat in the distal forearm by single photon absorptiometry.

The influence of subcutaneous fat on single photon (125I) absorptiometry (SPA) measurement of bone mineral content of the distal forearm was investigated. A fat correction model was tested by measurements on eight lean subjects with different amounts of porcine fat around their forearm, and further validated from measurements on 128 females. In addition, it is shown that the fat content in the distal forearm can be measured by SPA with a short-term precision at 1.9% in an obese subject and that it correlates well with total body fat (r2 = .7) measured by dual photon absorptiometry, skinfold thickness (r2 = .5), and body mass index (r2 = .6). By using this method in a double-blind placebo-controlled trial, hormonal substitutional therapy significantly decreased the forearm fat content without affecting the body weight in postmenopausal osteoporotic women.

Adipose Tissue↗
PubMed1989

Treatment of postmenopausal osteoporosis: is the anabolic steroid nandrolone decanoate a candidate?

Thirty-nine postmenopausal women (aged 55-75 years) with at least one osteoporotic fracture were allocated to one year of treatment with the anabolic steroid nandrolone decanoate (50 mg i.m. every 3 weeks) or placebo injection. Both groups also received a daily intake of 500 mg calcium. Thirty-six women (92%) completed the study. In the nandrolone decanoate-treated group the fat corrected bone mineral content in the proximal part of the distal forearm (measured by single photon absorptiometry) showed a significant increase of 3% compared with placebo (P less than 0.01), and the same tendency was seen in the bone mineral content of the distal part of the distal forearm and density of the lumbar spine (measured by dual photon absorptiometry). However, this did not reach significance. In the placebo group all bone mineral measurements remained unchanged. The biochemical estimates of bone formation (plasma bone Gla protein (BGP), serum alkaline phosphatase) and whole body retention (WBR) of 99mTc-diphosphonates were not statistically significantly changed by the nandrolone decanoate therapy. We conclude that treatment with nandrolone decanoate does increase the bone mineral content; however, this may not be due to a direct increase in bone formation. The mechanism may theoretically be a combination of decreased bone resorption and increased muscle mass, which both play a beneficial role in conserving bone.

Aged↗
PubMed1989

Nandrolone decanoate treatment of post-menopausal osteoporosis for 2 years and effects of withdrawal.

This study investigated the effects of nandrolone decanoate (ND) therapy (50 mg i.m. every 3 or 4 wk) on bone mass and soft tissue body composition in post-menopausal women. Twenty-two (22) women were followed up over a period of 30 mth, during which they received ND therapy for 12-24 mth and were treatment-free for the other 6-18 mth. While they were receiving treatment forearm bone mineral content (BMC) and lean body mass (LBM) increased, whereas fat mass (FM) decreased. After withdrawal of ND therapy the BMC, LBM and FM values all tended to return to pretreatment levels. Serum high-density-lipoprotein cholesterol showed a non-significant decrease, while serum low-density-lipoprotein cholesterol and serum total cholesterol remained unchanged during therapy. It was concluded that ND therapy can achieve an increase in BMC in post-menopausal women, but this is maintained only for as long as therapy is continued.

Aged↗
PubMed1989

Influence of soft tissue body composition on bone mass and metabolism.

Total body bone mineral (TBBM), lean body mass (LBM), and fat mass (FM) were measured by dual photon 153Gd absorptiometry in four female groups: (a) 27 patients with hip fracture; (b) 40 patients with spinal crush fracture; (c) 17 patients with osteoarthrosis, and (d) 26 healthy postmenopausal women. TBBM was significantly decreased in the two osteoporotic groups. The FM tended to be smaller in the two osteoporotic groups and larger in the osteoarthrotic group compared to the control group, whereas, LBM was virtually equal in all four groups. A significant negative correlation (p less than 0.01) was found between fasting urinary calcium corrected for creatinine and FM, whereas no relation between plasma bone Gla protein and FM could be demonstrated. We conclude that an increased fat mass after the menopause decreases bone resorption without a corresponding decrease in bone formation.

Absorptiometry, Photon↗
PubMed1989

Body composition measurement by dual photon absorptiometry: comparison with body density and total body potassium measurements.

Body composition was measured in 29 healthy adults (12 men and 17 women) by three different methods: Dual photon (153Gd) absorptiometry (DPA), body density measurements (BD) and measurements of total body potassium (TBK). Correlation and regression analysis with the body fat percentage (Fat%) measured by the three different methods gave r values between 0.83 and 0.90 and SEEs between 4.0 and 6.0 (Fat%). We conclude that DPA provides a new method of measuring body composition with precision and accuracy errors in the same range as the more established methods.

Adult↗
PubMed1989

The effect of hemiplegia on bone mass and soft tissue body composition.

The content of bone mineral (BMC), lean tissue, and fat tissue were measured by single and dual photon absorptiometry in both the paretic and the non-paretic limbs of 15 patients, hemiplegic due to cerebrovascular accident 23-38 weeks earlier. Compared with the non-paretic arm, the paretic arm had approximately 10% lower (P less than 0.01) BMC. This difference was largest at the measuring site with the highest ratio of trabecular to compact bone. The paretic leg had a 4% (P less than 0.001) lower BMC than the non-paretic leg. For both the arms and the legs, the lean content was lower (P less than 0.05) and the fat content higher (P less than 0.01) in the paretic than in the non-paretic. This was relatively more pronounced in the arms than in the legs. We conclude that partial immobilization, owing to paresis after a cerebrovascular accident, results in characteristic changes in the affected limbs, with a marked decrease in the content of bone and lean tissue and a pronounced increase in fatty tissue.

Adipose Tissue↗
PubMed1989

Estimation of total body composition from single photon absorptiometry measurement of forearm fat content.

The forearm fat content (FATarm, measured by single photon (125I) absorptiometry) and the 24-h urinary creatinine excretion (24 Ucrea) were determined in 29 healthy adults (12 males and 17 females), whose total body fat percentage was measured by three different methods: (i) Dual photon (153Gd) absorptiometry (DPA); (ii) body density measurements (BD); and (iii) total body potassium determinations (TBP). Lean body mass (by DPA, BD, and TBP) correlated significantly with 24 Ucrea (r = 0.87-0.89, standard error of estimate (SEE) = 5.2-6.3 kg). The total body fat percentage could be predicted from FATarm with SEEs at 3.4-5.8 (r = 0.85-0.88) and from 24 Ucrea + body weight with SEEs at 5.1-7.5 (r = 0.61-0.72). We conclude that the FATarm measurement represents a new tool for simple assessment of body composition on a group basis.

Adipose Tissue↗
PubMed1988

Blood pressure during oestrogen/progestogen substitution therapy in healthy post-menopausal women.

In order to explore the long-term effect of hormone (17 beta-oestradiol) substitution therapy on blood pressure in healthy post-menopausal women, we reviewed the data from five long-term (1-2 yr), double-blind, placebo-controlled studies carried out in our department over the last decade. Three of the studies related to early post-menopausal women (mean age 50 in all three cases) and two involved later post-menopausal women (mean ages 64 and 70, respectively). The systolic blood pressure values during hormonal substitution therapy showed no change in relation to those recorded during placebo administration, whereas the diastolic blood pressure fell slightly in all five studies. However, in that based on the oldest subjects, the results were not statistically significant. It was therefore concluded that hormone substitution therapy with 17 beta-oestradiol has no adverse effect on blood pressure, and may even have a beneficial action.

Adult↗
PubMed1988

The effect of a gonadotropin-releasing hormone agonist analog (nafarelin) on bone metabolism.

The effect on bone metabolism of an agonist analog of GnRH, nafarelin, was studied in 16 premenopausal women, who received 200 micrograms nafarelin/day for 6 months, and 9 premenopausal women, who received 400 micrograms nafarelin/day for 6 months, followed by a 6-month follow-up period. Bone mineral content in the forearm (measured by single photon absorptiometry) and in the spine (measured by dual photon absorptiometry) significantly decreased after 6 months of treatment with 400 micrograms nafarelin, but 6 months after termination of treatment all bone mineral measurements had returned to pretreatment levels. The bone mineral measurements in the 200 micrograms group did not change throughout the study. In both treatment groups the biochemical estimates of bone turnover increased significantly to postmenopausal levels. Withdrawal of treatment resulted in an abrupt decrease in the bone resorption parameters (fasting urinary hydroxyproline to creatinine and calcium to creatinine excretion ratios and serum phosphate), whereas there was a protracted fall in the bone formation parameters (plasma bone Gla protein and serum alkaline phosphatase) 6 months after termination of treatment. Our findings demonstrate that nafarelin in both doses increased biochemical indices of bone turnover, that 400 micrograms/day nafarelin resulted in a significant decrease in bone mineral content, and that these effects were reversible.

Adult↗
PubMed1988

Long-term precision of dual photon absorptiometry in the lumbar spine in clinical settings.

We have investigated the long-term in vivo precision of a dual photon spine scanner using three different Gd sources and compared it with that of the single photon scanner. Standard values were significantly different with the three Gd sources. With the second there was also a systematic increase of 2% per 60,000 cps in the 44 KeV channel as the source decayed, whereas no such shift was found with the other two sources. This resulted in a significant in vivo intrasource (P less than 0.05) and intersource (P less than 0.01) variation and a six-month reproducibility ranging from 3.7 to 8.1%. After correction for these systematic errors the clinically important 2-year reproducibility in 26 premenopausal women was 3.4 +/- 1.3% for spinal BMC and 3.7 +/- 1.7% for spinal BMD. In comparison, the forearm single photon scanner had a long-term precision of 1.0 +/- 0.3%. With the presented techniques spinal measurements may therefore require 11.6 times (3.4(2):1.0(2] as many participants as the forearm measurements to detect the same changes in bone mass.

Adult↗
PubMed1987

The long-term effect of oral and percutaneous estradiol on plasma renin substrate and blood pressure.

The long-term effect of percutaneous and oral estrogen replacement therapy on blood pressure, plasma renin substrate, and serum estrogens was examined in a 2 year placebo-controlled study with 110 early postmenopausal women. The women were allocated to four treatment groups: (1) oral cyclical combination of 2 mg estradiol valerate and cyproterone acetate, (2) oral placebo, (3) percutaneous 17 beta-estradiol, supplemented by 200 mg oral progesterone during the second year, or (4) percutaneous placebo cream. Systolic and diastolic blood pressure remained unchanged in both hormone treatment groups, whereas the diastolic blood pressure tended to increase in both placebo groups. Plasma renin substrate increased during oral treatment with estradiol, but remained unchanged with percutaneous estradiol. No correlation was found between blood pressure and plasma renin substrate. During percutaneous administration of estradiol, the serum concentrations of estrone and estradiol continued to rise after 3 months and reached a plateau at 6 months of therapy. Serum estrone but not estradiol showed the same pattern during oral estradiol therapy. No further changes in any of the measured variables were observed in the women treated with percutaneous estradiol after addition of cyclical oral progesterone. We conclude that both oral and percutaneous treatment with estradiol may provide protection against the age-related increase in diastolic blood pressure observed in early postmenopausal women, and that the metabolic steady state is not attained until after 3 months of estradiol therapy.

Administration, Cutaneous↗
PubMed1987

Effect of vitamin D2 and vitamin D3 on the serum concentrations of 1,25(OH)2D2, and 1,25(OH)2D3 in normal subjects.

Serum concentrations of vitamin D2 and vitamin D3 metabolites were measured in 19 normal subjects before and during treatment with either vitamin D2 or vitamin D3, 4000 IU per day for 8 weeks. Vitamin D2 treatment increased the serum concentration of 1,25(OH)2D2, but a corresponding decrease in 1,25(OH)2D3 resulted in an unchanged serum concentration of total 1,25(OH)2D. During treatment with vitamin D3, the serum concentration of 1,25(OH)2D metabolites was unchanged. We conclude that the production of 1,25(OH)2D is tightly regulated and that 1 alpha-hydroxylase does not discriminate between D2 and D3 metabolites in normal subjects.

Adult↗
PubMed1986

Prediction of body composition by age, height, weight, and skinfold thickness in normal adults.

In order to establish an easy and reliable method for estimating body composition, the lean body mass (LBM) and the fat mass (FM) were measured in vivo in 228 normal adults (130 women and 98 men) using dual photon (153Gd) absorptiometry. In addition, skinfold thickness was measured at two sites in each subject. Multiple regression equations of LBM and FM based on age, height, and weight were computed (r = .86 to .95, SEE = 2.1 to 2.9 kg). These correlations were only slightly improved in men, but not in women, when the results of the skinfold measurements were included in the calculations. We conclude that LBM and FM can be estimated in normal adults from age, height, and weight with a predictive error below 3 kg.

Adult↗