PubMed Health⌕ Search

Biomedical subjects

K Brixen

Publications and source records attributed to K Brixen.

At least 19 recordsLinked to original sources

Prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old, Danish men. Relation to sociodemography, physical dysfunction and low socioeconomic status: the Odense Androgen Study.

OBJECTIVE: To assess the prevalence of overweight, obesity and physical inactivity in 20- to 29-year-old men and to analyze whether sociodemography, physical dysfunction and low socioeconomic status are independent correlates of obesity and physical inactivity. DESIGN: Population-based, cross-sectional study. SUBJECTS: Seven hundred and eighty-three Caucasian, Danish men, aged 20-29 years recruited from 2042 respondents in a questionnaire survey of 3000 men, randomly drawn from the Danish Civil Registration System. METHODS: Questionnaire, interview and physical examination. RESULTS: The 783 included men and the 2042 questionnaire respondents matched the background population demographically. The 783 men matched the questionnaire respondents as regards BMI, physical activity, chronic disease, medication, smoking, sociodemography and socioeconomic status. The prevalence of overweight and obesity was 31.7 and 7.9%, respectively (World Health Organization criteria). Using waist circumference (WC) cutoffs of 94 and 102 cm, the prevalence was 16.2 and 10.6%, respectively; 24.4% were physically inactive. BMI and WC increased significantly from age 20 to 29 years. Physical activity decreased significantly with age and correlated inversely with WC, but not with BMI. Occupation, geography, partner status, fatherhood and tobacco exposure were independently related with obesity and physical inactivity. Obesity was also related to musculoskeletal complaints, whereas chronic diseases and low educational level were associated with physical inactivity. Age was not independently related with either outcome. CONCLUSION: In affluent societies, sociodemographic changes may partly explain the age-related decrease in physical activity and the parallel increase in WC and BMI.

Adiposity↗

Geometry of the proximal femur in relation to age and sex: a cross-sectional study in healthy adult Danes.

PURPOSE: To describe the natural variation in hip geometry in relation to Danish population characteristics, and to establish normal reference values. MATERIAL AND METHODS: We included 249 healthy individuals (94 M and 155 F, aged 19-79 years) and measured hip-axis-length (HAL), neck-width (NW), neck-shaft-angle (NSA), and femoral head-radius (HR) on dual-energy X-ray absorptiometry (DXA) screen images. RESULTS: HAL, NW, HR, and NSA were higher in men than in women (10.9 +/- 0.7 vs. 9.5 +/- 0.6 cm (P<0.001), 3.8 +/- 0.3 vs. 3.3 +/- 0.3 cm (P<0.01), 2.5 +/- 0.3 vs. 2.3 +/- 0.2 cm (P< 0.001), and 131 +/- 5 vs. 129 +/- 5 degrees (P< 0.01). NSA was higher in post-menopausal than in pre-menopausal women (130 +/- 4 vs. 128 +/- 5 degrees (P<0.001)). In multiple regression analysis, HAL, NW, and HR were positively related to body height in both sexes (R = 0.20 to 0.63, P<0.05 to P<0.001). In females, NSA was positively related to body height (R = 0.20, P<0.05) and negatively to body weight (R = -0.30, P<0.01). NW increased with age in men (R = 0.34, P<0.01) but not in women. CONCLUSION: Hip dimensions differ between genders in the Danish population. HAL, NW, and HR depend on body height. Finally, NW increases with age in men but not in women.

Absorptiometry, Photon↗

Response rates to oestrogen treatment in perimenopausal women: 5-year data from the Danish Osteoporosis Prevention Study (DOPS).

OBJECTIVE: To characterise women with no response or with a good response to hormone replacement therapy (HRT), evaluated by change in bone mineral density (BMD). DESIGN: Nested case-control study within a comprehensive cohort study. SUBJECTS AND METHODS: In the Danish Osteoporosis Prevention Study (DOPS), perimenopausal women were allocated to either HRT or no HRT. In the present study, we included 466 women who had been treated with HRT for 5 years and 466 untreated women from the same cohort. Non-responders were women in the treatment group, who decreased in BMD more than the mean decrease observed in the untreated group. Good responders were women with a larger increase in BMD than the upper 95% percentile of untreated women. Baseline characteristics were evaluated as predictors of response to HRT. RESULTS: 8.4 and 5.6% were classified as non-responders, whereas 25 and 57% were good responders according to changes in BMD of the femoral neck and lumbar spine, respectively. Combining measuring sites, 2.6% were non-responders and 20% were good responders. Non-responders at the femoral neck were more often smokers and had a lower spine BMD. Good responders were older, had a higher body weight, and higher alcohol consumption. In addition, good responders at both measurements sites had a lower BMD at the total hip. CONCLUSION: A favourable BMD response to HRT can be expected in most post-menopausal women especially if they are non-smokers with a moderate--as opposed to low--alcohol intake, a high body mass and a low initial hip BMD.

Absorptiometry, Photon↗

Morphometric X-ray absorptiometry: reference data for vertebral dimensions in a population-based sample of young Danish men.

PURPOSE: To determine reference values for vertebral heights in healthy young Danish males using morphometric X-ray absorptiometry (MXA). MATERIAL AND METHODS: A population-based study group of 487 males aged between 20 and 30 years (mean 25 years) from the county of Funen, Denmark, were recruited. Using a Hologic QDR 4500 (dual energy X-ray absorptiometry) DXA-scanner, MXA scans covering the vertebrae from T4 to L4 were acquired for each subject. Anterior (Ha), middle (Hm), and posterior (Hp) heights of the thoracic (T4-T12) and lumbar (L1-L4) vertebral bodies were measured. Moreover, wedge, mid-wedge, crush I, and crush II ratios were calculated. RESULTS: No correlation between vertebral dimensions and crush indices on the one hand and age or weight on the other were found. Body height, however, correlated significantly with the cumulated vertebral heights. Reference data for vertebral dimensions, wedge, mid-wedge, crush I, and crush II are tabulated. CONCLUSION: The anterior, middle, and posterior heights of the vertebral bodies of T4 to L4 can be measured reproducible with MXA. In young men, the cumulative vertebral heights correlated with body height but not with age. Moreover, the wedge and crush indices were unrelated of both age and height.

Absorptiometry, Photon↗

Cushing's disease in childhood as the first manifestation of multiple endocrine neoplasia syndrome type 1.

OBJECTIVE: To describe three cases of Cushing's disease in children with multiple endocrine neoplasia type 1 (MEN1), as clinical manifestations of MEN1 are very rare in childhood. DESIGN AND METHODS: A retrospective review of three cases of Cushing's disease diagnosed between 1997 and 1999. Genetic screening for MEN1 gene mutation was performed in each patient. RESULTS: An ACTH-secreting microadenoma was diagnosed in three children, aged 11-13 years, presenting with growth retardation and weight gain over a period of 3-4 years. All patients had successful transsphenoidal adenomectomies. Primary hyperparathyroidism was subsequently diagnosed in two of the patients, and in the monozygotic twin of one of the patients. A new mutation in the MEN1 gene (Tyr351His) was identified in two of the patients and the affected members of their families. In the third patient a de novo MEN1 gene mutation (Leu444Pro) was found. CONCLUSIONS: MEN1 has to be considered in all children with tumours of the pituitary gland, and in those presenting with primary hyperparathyroidism. The children and their families should be advised to seek genetic counselling. We suggest that careful growth records be kept for children at risk of developing inherited MEN1 and, in the event of a decelerating growth rate, further diagnostic evaluation be undertaken with regards to ACTH-secreting pituitary tumours.

Adenoma↗

Effect of long-term hormone replacement therapy on tissue factor pathway inhibitor and thrombin activatable fibrinolysis inhibitor in healthy postmenopausal women: a randomized controlled study.

It was recently reported from the Women's Health Initiative that healthy women using combined hormone replacement therapy (HRT) for 5 years have an increased cardiovascular risk. We hypothesize that the increased risk is confined to subgroups of atherosclerotic women. Such women may have higher arterial tissue factor expression and higher thrombin formation, and changes in tissue factor pathway coagulation inhibitor (TFPI) and thrombin activatable fibrinolysis inhibitor (TAFI) may be deleterious. Healthy postmenopausal women (n = 719) were randomized to hormone therapy [n = 357; opposed (n = 290) and unopposed (n = 67)] or no treatment (n = 362). Plasma TFPI and TAFI and the TFPI -287T/C and TAFI -438G/A polymorphisms were measured 5-6 years after randomization. Concentrations of TFPI were significantly lower in the hormone group than in the control group (P < 0.001) and in all genotypes of the TFPI polymorphism. Overall, concentrations of TAFI did not differ between the two groups but were reduced by hormone therapy in homozygotes for the rare TAFI -438 A allele (P < 0.05). The hormone effects on TFPI and TAFI were similar in smokers and non-smokers and in women using unopposed and opposed therapy. The observed decrease in TFPI may contribute to the increased cardiovascular risk associated with HRT.

Arteriosclerosis↗

Decreased trabecular bone biomechanical competence, apparent density, IGF-II and IGFBP-5 content in acromegaly.

BACKGROUND: Earlier studies on the effect of excess growth hormone (GH) on trabecular bone have been conflicting. Since insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) in part mediate the effects of GH, the present study aimed to investigate trabecular bone composition of these growth factors in relation to biomechanical properties in acromegaly. MATERIALS AND METHODS: Trabecular bone biomechanical competence (compression test), apparent density (peripheral quantitative computed tomography, pQCT), and bone matrix contents of calcium (HCl hydrolysis) and IGFs (guanidinium-HCl extraction) were measured in iliac crest biopsies from 13 patients with active acromegaly (two women and 11 men, aged 21-61 years) and 21 age- and sex-matched controls (four women and 17 men, aged 23-64 years). RESULTS: Trabecular bone pQCT was reduced in acromegalic patients compared with controls (P = 0.005), as was biomechanical competence (P < 0.05 for all measures). These parameters were significantly positively correlated in both acromegalic patients and controls. The calcium content of trabecular bone was significantly increased in patients compared with controls. No significant differences were found in trabecular bone content of IGF-I, IGFBP-3, or osteocalcin. However, IGF-II and IGFBP-5 content was decreased (P < 0.001 and P < 0.05, respectively). CONCLUSIONS: The present study demonstrates reduced trabecular biomechanical competence and apparent density in acromegaly, supporting previous observations of an unfavourable effect of chronic excess GH on the axial skeleton. Furthermore, we demonstrate decreased trabecular bone content of IGF-II and IGFBP-5 in these patients. However, we found no direct causal relationship between trabecular bone density and bone content of IGF-system components.

Acromegaly↗

Low bone mineral density in the femoral neck of medieval women: a result of multiparity?

An archaeological investigation of a medieval cemetery gave us the opportunity to investigate 49 Danish skeletons dating from 1000 to 1250 A.D. and to compare them with 298 contemporary Danes (aged 19-79 years) and assess the millennial trend in bone mineral density (BMD) in populations considered genetically closely related. BMD and bone mineral apparent density (BMAD) of the femoral neck were measured by dual-energy X-ray absorptiometry (DEXA) and transformed into z scores. BMD(zscore) was significantly lower in medieval women (-0.54 +/- 0.25, p = 0.04), whereas BMD(zscore) in medieval men was significantly higher (0.55 +/- 0.22, p = 0.02). In medieval women, BMD(zscore) tended to increase with age (r = 0.42, p = 0.07), whereas no change was seen in men (r = 0.19, not significant [n.s.]). Also, BMAD(zscore) was significantly elevated in medieval men (1.00 +/- 0.28, p < 0.01), but in medieval women no difference was found (-0.28 +/- 0.21, n.s.). However, the correlation between BMAD(zscore) and age was significant in the medieval women where it increased with advancing age (r = 0.49, p = 0.03). In conclusion, medieval women had lower BMD when compared with contemporary women, but this relationship was reversed in women who survived to older ages. In contrast, medieval men had significantly higher BMD as compared with contemporary men at all ages. The observed lower BMD in medieval women can be explained by the well-known selective mortality among the younger women. A high birth rate and prolonged periods of lactation are the main reasons for the observed increased mortality, and therefore can also very likely explain the associated low BMD. The increase in the incidence of osteoporosis in modern elderly women could possibly, or partially, be explained by the survival of women who would have died prematurely had they lived in earlier centuries.

Bone Density↗

Biochemical markers of bone metabolism reflect osteoclastic and osteoblastic activity in multiple myeloma.

In order to evaluate the use of recently developed assays of bone metabolism in multiple myeloma we performed a histomorphometric study of bone biopsies in 16 myeloma patients. Furthermore, we measured the levels of interleukin-6 (IL-6), soluble IL-6 receptor (IL-6sR), IL-1beta, tumour necrosis factor (TNF) alpha, TNFbeta, and transforming growth factor (TGF) beta in marrow plasma aspirated from the biopsy area. MARKERS OF BONE RESORPTION: The N-terminal telopeptide of collagen I (Ntx) in urine showed a strong positive correlation with the dynamic histomorphometric indices of bone resorption (r=0.68-0.72). Slightly weaker correlations were observed between the dynamic indices of bone resorption and the C-terminal telopeptide of collagen I (ICTP) in serum (r= 0.57-0.62) and deoxypyridinoline (Dpyr) in urine (r= 0.54), whereas urinary pyridinoline (Pyr) did not correlate with the histomorphometric findings. MARKERS OF BONE FORMATION: Serum C-terminal propeptide of procollagen I (PICP) and serum bone-specific alkaline phosphatase (bAP) showed significant correlations with the dynamic parameters of bone formation (r=0.57-0.58), whereas serum osteocalcin and serum total AP did not. CYTOKINES: Highly significant correlations were observed between marrow IL-6 and rates of bone resorption and activation frequency (r=0.76-0.82) and with serum ICTP (r=0.63). Minor, but also significant correlations were observed between the resorptive indices and IL-6sR and IL-1beta. The data indicate that measurements of the biochemical markers of bone metabolism may be useful in monitoring myeloma bone disease, and might thus be of use for dose titration of bisphosphonate therapy.

Aged↗

Polymorphisms in the vitamin D receptor gene and bone mass, bone turnover and osteoporotic fractures.

BACKGROUND: Vitamin D is essential for normal bone metabolism. Polymorphisms in exon 2, intron 8 and exon 9 of the vitamin D receptor (VDR) gene have previously been found to be associated with bone mass and bone turnover. MATERIALS AND METHODS: We examined the effect of these polymorphisms, separately and in combination, on bone mineral density (BMD), bone turnover, and the prevalence of osteoporotic fractures in 192 osteoporotic patients and 207 normal controls. The four polymorphisms were determined by RFLP using Fok I (T2-C), Bsm I (intron 8), Apa I (intron 8) and Taq I (T1055-C) after PCR. RESULTS: We did not find any association between the Fok I polymorphism and bone mass, bone turnover or prevalence of osteoporotic fractures. We found that BB + Bb-genotypes were more frequent in patients with osteoporotic fractures (chi2 = 3.50, P = 0. 06). Furthermore, BMD of the intertrochanteric region (P < 0.0001, ANOVA) as well as the total hip (P < 0.01, ANOVA) were higher in individuals with the bb-genotype. The Apa I and the Taq I polymorphisms were not distributed differently among osteoporotic patients and normal controls. Apa I was not associated with differences in BMD. BMD of the intertrochanteric region was higher in individuals with the TT-genotype compared with individuals with the Tt- or tt-genotypes (P < 0.01, ANOVA), while no differences could be demonstrated in BMD of the lumbar spine, femoral neck, trochanter or Wards triangle. Combining the genotypes generally reflected the differences caused by the Bsm I polymorphism. CONCLUSION: We have found that the B-allele of the Bsm I polymorphism in the 3' untranslated region of the VDR was associated with low BMD at the hip, and tended to be associated with osteoporotic fractures. The translation initiation polymorphism in the VDR does not affect BMD and is not associated with osteoporotic fractures in men or women.

Adult↗

Growth hormone treatment in adults with adult-onset growth hormone deficiency increases iliac crest trabecular bone turnover: a 1-year, double-blind, randomized, placebo-controlled study.

The effects of growth hormone (GH) substitution on bone metabolism were evaluated by dynamic histomorphometry on iliac crest bone biopsies. Twenty-nine patients, aged 21-61 years (mean 45.5 years), with adult-onset GH deficiency (GHD) were randomized to receive subcutaneous injections with GH (2 IU/m2/day = 0.67 mg/m2/day) or placebo for 12 months. Serum insulin-like growth factor I (IGF-I) levels increased 263 +/- 98% (mean +/- SD) during GH treatment (p < 0.0001). In the GH group, osteoid surface increased during treatment from 11% (3-15%) (median [25-75 percentiles]) to 21% (10-27%) (p = 0.01) and mineralizing surface from 4% (1-8%) to 11%(7-16%) (p = 0.04). Moreover, erosion surface tended to increase in the GH group from 2% (1-3%) to 4% (3-5%) (p = 0.07). The quiescent surface decreased in the GH group from 87% (83-96%) to 74% (68-87%) (p = 0.01). The adjusted appositional rate, mineral apposition rate, bone formation rate, bone erosion rate, mineralization lag time, and osteoid thickness remained unchanged during treatment. Erosion depth showed a trend toward increase in the GH group (p = 0.09), whereas wall thickness was unchanged. Bone balance at the remodeling unit level and activation frequency were unchanged. At the tissue level, bone erosion rate increased significantly from 26% (17-36%)/year to 39% (23-72%)/year (p = 0.03). Similarly, the bone formation rate at the tissue level tended to increase, from 24% (15-31%)/year to 36% (17%-63%)%/year (p = 0.06). Finally, bone balance at the tissue level decreased significantly from 1% (-2-2%)/year to -5% (-13-1%)/year (p = 0.01). No significant difference in change was seen in the cancellous bone volume. We conclude that 12 months of GH substitution therapy increases trabecular bone turnover. Moreover, our data suggest that bone balance at the bone multicellular unit level is not changed to positive.

Adult↗

Primary hyperparathyroidism: short-term changes in bone remodeling and bone mineral density following parathyroidectomy.

Changes in bone remodeling and bone mineral density were observed during a period of 6 months after surgery in 24 patients with primary hyperparathyroidism (20 women and 4 men; age 54+/-12 years, range 26-69 years). All bone markers declined significantly within the 6 month follow-up period, but the time course for changes in renal N-terminal telopeptide of type 1 collagen (NTx) excretion differed from those of the other markers by a steep and significant reduction (p < 0.05) after less than 1 month. During the 6 month period, bone mineral density (BMD) increased significantly at all sites measured (p < 0.05) apart from the femoral neck and the proximal and midforearm. The greatest increase of 4.2% was observed in the trochanteric region (p < 0.001). The increase in BMD in spine, trochanteric, and intertrochanteric regions of the hip correlated inversely with baseline forearm BMD values (p < 0.05). Baseline bone markers (serum alkaline phosphatase [AP], serum bone AP, serum pyridinoline crosslinked telopeptide of type 1 collagen, urinary hydroxyproline, urinary osteocalcin), as well as baseline histomorphometric indices of bone turnover (eroded and labeled surface, bone formation rate, activation frequency, and cortical porosity) were positively correlated with changes in spinal BMD over 6 months (p < 0.05). It was concluded that, within 6 months after parathyroidectomy, patients with primary hyperparathyroidism obtain normalization of bone remodeling and a substantial increase in bone mineral density in regions rich in cancellous bone but no significant changes in regions with predominantly cortical bone.

Aged↗

Primary hyperparathyroidism: effect of parathyroidectomy on regional bone mineral density in Danish patients: a three-year follow-up study.

Changes in skeletal remodeling (biochemical bone markers) and regional bone mineral density (spine, hip, and forearm bone mineral density [BMD]) were observed for 3 years in 20 patients (15 women and 5 men; age 54 +/- 11 years, range 29-69 years) after successful surgery for primary hyperparathyroidism (PHPT). Fifteen PHPT patients were compared with 15 normal controls who were exactly matched with respect to age, gender, and menopausal status (10 women and 5 men; age 53 +/- 12 years, range 29-65 years [PHPT] and 29-66 years [controls]). All bone markers (serum osteocalcin, bone alkaline phosphatase, and type I collagen telopeptide [ICTP], and urinary hydroxyproline and NTx/creatinine ratio) declined significantly and reached normal levels within 6 months. No major changes took place during the remaining 2.5 years, apart from urine hydroxyproline, which disclosed a small peak around 12 months with a further decline towards study end (p < 0.05). Bone mineral density increased significantly in all regions (p < 0.001). At all locations, except the intertrochanteric region of the hip, the increase continued from 6 months until study end (p < 0.05). The increase in BMD was unequally distributed among regions (p < 0.001). The increase at the proximal forearm was less than in the spine (p < 0.05), the trochanteric region of the hip (p < 0.05), and the distal forearm (p < 0.05). No difference in BMD increase was observed between men, and pre- and postmenopausal women. Compared with the matched control group, PHPT patients had significantly lower BMD at baseline in the proximal (p < 0.02) and distal (p < 0.05) forearm. Furthermore, during the 3-year follow-up period, the PHPT patients showed a significant increase in BMD compared with controls in the spine (p < 0.005), the trochanteric and intertrochanteric regions of the hip (p < 0.005 and p < 0.05, respectively), and the distal forearm (p < 0.005). In conclusion, bone remodeling is normalized within the first 6 months after successful parathyroid surgery, with no major changes during the following 2.5 years. Bone mineral density increases at both cancellous and cortical sites, but in predominantly cortical bone, the recovery in BMD is less than in cancellous bone-rich areas.

Adenoma↗

Primary hyperparathyroidism: whole-body bone mineral density in surgically treated Danish patients: a three-year follow-up study.

Whole-body bone mineral density (BMD) and body composition were measured before surgery in 25 patients (20 women and 5 men, aged 53 +/- 13 years, range 26-73 years) with mild to moderate primary hyperparathyroidism (PHPT) and compared with 25 controls exactly matched with respect to age, gender, and menopausal status. Fifteen pairs of matched patients and controls were reexamined 3 years later (5 men and 10 women, aged 53 +/- 12 years in both groups). In the untreated PHPT patients, whole-body BMD was 95.4% +/- 10.5% (SD) of control BMD (p < 0.05). Body weight and height, body mass index, whole-body fat mass, and lean body mass did not differ significantly between the groups. Relative to values in matched controls, whole-body bone mineral content (BMC) and BMD increased by 4.4% and 3.0%, respectively, in PHPT patients (p < 0.005) during the 3-year follow-up. Neither whole-body BMC nor BMD differed between patients and controls after the 3-year follow-up. A positive correlation was observed between initial serum calcium levels and the 3-year increase in whole-body BMD (r(s) = 0.645, p < 0.01). Baseline serum osteocalcin, serum pyridinoline crosslinked telopeptide of Type I collagen and several histomorphometric indices of trabecular bone turnover (eroded and labeled surfaces, bone formation rate, and activation frequency) also correlated positively with the subsequent increase in whole-body BMD. Six patients disclosed transient postoperative secondary hyperparathyroidism, probably due to hungry bones. Four of these patients completed 3 years of follow-up and had higher increases in whole-body BMD than the remaining normo-parathyroid patients (7.9% +/- 4.5%, range 4.3-14.3% versus 1.9% +/- 2.1%, p < 0.01). It is concluded that Danish patients with mild to moderate PHPT only reveal small reductions in whole-body mineral density. Furthermore, within 3 years after parathyroid surgery, most of the lost bone mineral is regained even in patients with initial high bone turnover. Finally, PHPT in these patients is not associated with substantial changes in body compositions.

Adult↗

Increased cortical bone content of insulin-like growth factors in acromegalic patients.

To investigate cortical bone composition and the role of the insulin-like growth factor (IGF) system in active acromegaly, iliac crest bone biopsies were obtained from 15 patients (3 women and 12 men), aged 21-64 yr (mean, 45.6 yr), and 25 age- and sex-matched controls (8 women and 17 men), aged 22-66 yr (mean, 44.6 yr). Levels of IGF-I, IGF-II, IGF-binding protein-3 (IGFBP-3), IGFBP-5, and total protein were determined in extracts obtained after ethylenediamine tetraacetate and guanidine hydrochloride extraction. Osteocalcin and calcium were determined in extracts after HCl hydrolysis. Cortical bone contents of IGF-I, IGF-II, and IGFBP-5 were significantly elevated in the acromegalic patients compared with control values [91% (P < 0.001), 44% (P < 0.04), and 115% (P < 0.004), respectively]. There was no significant difference in IGFBP-3, osteocalcin, protein, and calcium between patients and controls. This study suggests that the increased levels of growth factors in cortical bone from acromegalics is a reflection of local production, secondary to a chronic systemic excess of GH and IGF-I.

Acromegaly↗

Does growth hormone therapy in adult patients with growth hormone deficiency protect against bone loss?

Fracture incidence is increased in growth hormone deficiency (GHD). However, the efficacy of growth hormone (GH) in the prevention of fractures in GHD is not documented. GH is important to attain normal peak bone mass; it increases bone mass in children and adolescents, but is less important with increasing age and is insignificant above the age of 55-60 years old. Placebo-controlled trials of 12 months' duration have failed to improve bone mass density, while uncontrolled studies have suggested that GH treatment for 2-4 years may increase bone mass by 0.5 of a standard deviation in adults. Given the current high price of GH treatment, however, routine substitution with the intention to decrease fracture incidence in adult GHD patients is not likely to be cost effective. GH substitution should probably be extended until peak bone mass has been achieved, and repeated dual energy X-ray scan measurements with intervals of 1-2 years could be helpful in deciding when to stop treatment.

Adolescent↗

Effects of growth hormone treatment on serum levels of insulin-like growth factors (IGFs) and IGF binding proteins 1-4 in postmenopausal women.

BACKGROUND AND OBJECTIVE: Insulin-like growth factor binding proteins (IGFBPs) modulate the actions and bioavailability of insulin-like growth factors (IGFs), however, their regulation in vivo is incompletely understood. In this study we investigated the effects of different doses of growth hormone (GH) on circulating levels of IGFs and IGFBPs. DESIGN: The study was double-blind and placebo-controlled. Patients were treated with either GH in doses of 0.05, 0.10, or 0.20 lU/kg/day of placebo for one week. PATIENTS: Forty post-menopausal women aged 52-73 years with low bone mass. MEASUREMENTS: Serum IGF-I and IGF-II were measured by RIA while IGFBP-1-3 were measured by Western ligand blot (WLB) and compared with determinations by specific immunoassays. IGFBP-4 was measured by WLB alone. RESULTS: Both IGF-I (P < 0.001) and IGF-II (P < 0.01) increased significantly during GH treatment. Additionally, IGFBP-1 (P < 0.001) and IGFBP-2 (P < 0.001) decreased significantly while IGFBP-3 (P < 0.001) and IGFBP-4 (P < 0.05) increased all in a dose-dependent manner. Stepwise (backwards) multiple regression analyses showed that the changes in IGF-I and IGF-II, and age correlated with the change in serum IGFBP-1. Both GH-dosage, the increase in IGF-II, and body mass index correlated with the decrease in IGFBP-2. Furthermore, the increase in serum IGF-I, IGF-II, and triiodothyronine correlated with the increase in IGFBP-3. Moreover, GH-dosage correlated with the increase in serum IGFBP-4. CONCLUSION: GH significantly increased serum IGF-I, IGF-II, IGFBP-3, and IGFBP-4 and decreased serum IGFBP-1 and IGFBP-2 in post-menopausal women.

Aged↗