AB1241 BONA MINERAL DENSITY IN JUVENILE ONSET MIXED CONNECTIVE TISSUE DISEASE AFTER LONG-TERM DISEASE DURATION - A CASE-CONTROL STUDY

Background

Rheumatic diseases are associated with reduced bone mineral density (BMD) as measured by Dual Energy x-ray absorptiometry (DXA). Mixed connective tissue disease (MCTD) is a rare connective tissue disease, and about 25% of all cases have a pediatric presentation. One study implies that osteoporosis is common in postmenopausal women with MCTD (1), but data regarding BMD and osteopenia are lacking in younger patients with the disease.

Objectives

To assess the BMD in a cohort of juvenile mixed connective tissue disease (JMCTD) patients compared to a matched control group.

Methods

BMD was measured in a cohort of 52 JMCTD patients with mean age 28.2 years (SD 10.3) and mean disease duration 16.2 years (SD 10.3), and 52 controls matched for age and gender. Inclusion criteria were fulfilment of the Kasukawa- or the Alarcon-Segovia criteria and symptom debut before the age of 18 years.

Results

Patients and controls did not differ in age, body mass index, smoking habits, level of physical activity or vitamin D status (Table 1). Forty-four (85%) were female. Patients were shorter and had lower body weight compared to controls. None had had osteoporotic fractures. Patients over 20 years of age at examination had significantly lower BMD in the spine, femoral neck, proximal- and distal radius. Patients also had lower T-score compared to matched controls.

Table 1.VariableJMCTD patients (n=52)Controls (n=52)P valueBMI, kg/m222.7 (3.5)23.4 (3.0)0.239Height, cm166.0 (7.5)170.1 (8.5)0.016Weight, kg63.0 (12.1)68.1 (12.1)0.033Never smokers, n (%)35 (67)34 (65)0.83Moderate physical activity (hours/week), median (range)2.0 (0-28)1.2 (0-30.0)0.278Vitamin D*, nmol/l, median (range)50.0 (27-106)51.5 (23-115)0.829BMD, gm/cm2Spine L2-L41.19 (0.13)1.25 (0.10)0.110< 20 years (n = 14, 27%)1.14 (0.21)1.17 (0.11)0.496>20 years (n = 38, 73%)1.19 (0.12)1.26 (0.10)0.018Femoral neck0.97 (0.12)1.04 (0.09)0.006>20 years0.97 (0.12)1.04 (0.09)0.002Proximal radius0.79 (0.12)0.86 (0.09)0.007>20 years0.79 (0.12)0.86 (0.09)0.013Distal radius0.40 (0.07)0.50 (0.10)<0.001>20 years0.41 (0.07)0.51 (0.10)<0.001T-score >20 yearsSpine L2-L4, median (range)-0.40 (-2.3 to 2.0)0.29 (-1.4 to 1.8)0.006Femoral neck, median (range)-0.50 (-2.2 to 2.1)0.40 (-1.7 to 1.6)0.007Proximal radius, median (range)-0.90 (-0.2 to 1.6)-0.30 (-0.2 to 1.3)0.044Distal radius, median (range)-1.0 (-3.0 to 1.3)0.20 (-2.6 to 3.8)<0.001

All values are mean (SD) unless otherwise stated

Conclusion

Bone mineral density was impaired in JMCTD patients after 16 years disease duration compared to matched controls.

References

[1]Bodolay E et. Al, Osteoporosis in mixed connective tissue disease, Clin Rheumatol. 2003

Disclosure of Interests

None declared

AB0902 BONE HEALTH IN PATIENTS WITH JUVENILE ONSET DERMATOMYOSITIS ASSESSED AFTER LONG-TERM FOLLOW-UP; A CASE CONTROL STUDY

Background:

Patients with juvenile dermatomyositis (JDM) are at risk of developing low bone mineral density (BMD) and not reach peak bone mass, mainly due to prednisolone (pred) treatment [1], making them prone to osteoporotic fractures later in life

Objectives:

To compare BMD in longterm JDM patients (Pts) with that of controls (Ctr); and in Pts explore how disease variables affect BMD.

Methods:

Pts (n=59) were clinically examined median 16.8y (range 6.6 - 27.0 y) after disease onset and compared 1:1 with age/sex matched Ctr. Dual-energy X-ray absorptiometry (DXA) was used to measure BMD and Z-scores in whole body (WB), lumbar spine at L2-L4 (spine). In those ≥ 20y; also proximal (PR) and distal 1/3 radius (DR), and total hip were examined. Pred at follow up was reported, and cumulative dose calculated. Bone remodeling factors: C-terminal telopeptide (CTX), amino-terminal propeptide (P1NP) and 25(OH)Vitamin D (VitD), were measured in serum.

Results:

BMD WB was lower in Pts than Ctr, and both WB and spine BMD and Z scores were lower in Pts than Ctr <20 years (Tbl 1). DR BMD and Z-score were both lower in Pts ≥20y. Serum analysis showed lower VitD was lower in Pts than Ctr. In Pts ≥ 20y Vit D was lower and eSR was higher compared to Ctr.

In Pts ≥ 20y: moderate negative associations were found between both BMD WB and spine, and pred use at follow up (R`s = -0.43), and between BMD PR and VitD (R= -0.34). There was a positive moderate association between Z-score PR and CTX (-0.45) not found in Ctr, and between Z-score total hip and cumulative pred dose (R = 0.38). All p <0.05.

In Pts <20y moderate negative associations were found between Z-score for spine and months of pred use and cumulative pred doses (R`s = -0.40 and -0.48, p<0.05). Other associations found in Pts <20y were also found in respective Ctr.

Conclusion:

We found that Pts bone health was affected differently in young and adult JDM-Pts. Association analysis between BMD, Z-scores and medication and/or bone remodeling factors were not conclusive. We will perform linear regression analysis to determine if and how BMDs and Z-scores are dependent on pred use, time and doses, and factors important for bone remodeling.

Table 1.

Characteristics, disease variables, BMD and Z-scores in JDM Pts and Ctr

Pts(n=59)Pts < 20y(n=28)Pts ≥ 20y(n=31)Ctr(n=59)Ctr < 20y(n=28)Ctr ≥ 20y(n=31)Age, y21.5 (6.7-55.4)15.3 (6.7-19.8)34.3 (20.4-55.4)21.6 (6.2-55.4)14.4 (6.2-20.1)34.2 (20.5-55.4)Female36 (61)20 (71.4)16 (51.6)36 (61)20(71.4)16 (51.6)BMI, kg/m222.3 (4.8)20.3 (4.6)24.0 (4.4)22.7 (4.5)21.4 (5.2)23.9 (3.5)Height, cm164.9 (14.7)157.1 (15.9)171.8 (9.1)167.3 (15.8)*159.8 (18.3)174.0 (9.2)Fracture any19 (32.2)NANA21 (36.8)NANABMD, g/cm2 Whole body1.10 (0.15)1.01 (0.13)1.18 (0.10)1.13 (0.14)*1.06 (0.16) †1.19 (0.08) Spine, L2-L41.12 (0.23)0.99 (0.21)1.24 (0.18)1.17 (0.22)1.07 (0.27)†1.26 (0.11) Distal radiusNA0.87 (0.09)NA0.93 (0.11) ††Z-score Whole body-0.07 (1.08)-0.39 (0.99)0.21 (1.10)0.27 (0.90)0.28 (1.01) † †0.26 (0.71) Spine, L2-L4-0.16 (1.2.)-0.39 (1.01)0.06 (1.34)0.4 (1.02)0.25 (1.21) †0.24 (0.84) Distal radiusNA-0.76 (1.03)NA-0.05 (0.87)**

y: years, BMI: Body mass index, NA: not applicable. Values are: median age (range), median (IQR), n (%) or mean (SD). p-values *p<0.05, **p<0.01 when comparing Pts and Ctr and † p<0.05, †† p<0.01 when comparing Pts and Ctr < and ≥ 20 years.

References:

[1]Stewart, W.A., et al., Bone mineral density in juvenile dermatomyositis: assessment using dual x-ray absorptiometry. Arthritis Rheum, 2003. 48(8): p. 2294-8.

Words: 3555

Disclosure of Interests:

None declared

Consensus statement from 2nd International Conference on Controversies in Vitamin D

The 2nd International Conference on Controversies in Vitamin D was held in Monteriggioni (Siena), Italy, September 11-14, 2018. The aim of this meeting was to address ongoing controversies and timely topics in vitamin D research, to review available data related to these topics and controversies, to promote discussion to help resolve lingering issues and ultimately to suggest a research agenda to clarify areas of uncertainty. Several issues from the first conference, held in 2017, were revisited, such as assays used to determine serum 25-hydroxyvitamin D [25(OH)D] concentration, which remains a critical and controversial issue for defining vitamin D status. Definitions of vitamin D nutritional status (i.e. sufficiency, insufficiency and deficiency) were also revisited. New areas were reviewed, including vitamin D threshold values and how they should be defined in the context of specific diseases, sources of vitamin D and risk factors associated with vitamin D deficiency. Non-skeletal aspects related to vitamin D were also discussed, including the reproductive system, neurology, chronic kidney disease and falls. The therapeutic role of vitamin D and findings from recent clinical trials were also addressed. The topics were considered by 3 focus groups and divided into three main areas: 1) "Laboratory": assays and threshold values to define vitamin D status; 2) "Clinical": sources of vitamin D and risk factors and role of vitamin D in non-skeletal disease and 3) "Therapeutics": controversial issues on observational studies and recent randomized controlled trials. In this report, we present a summary of our findings.

The role of delayed bone age in the evaluation of stature and bone health in glucocorticoid treated patients with Duchenne muscular dystrophy

Background

Low bone mineral density and an increased risk of appendicular and vertebral fractures are well-established consequences of Duchenne muscular dystrophy (DMD) and the risk of fractures is exacerbated by long-term glucocorticoid treatment. Monitoring of endocrine and skeletal health and timely intervention in at-risk patients is important in the management of children with DMD.

Methods

As part of the Norwegian Duchenne muscular dystrophy cohort study, we examined the skeletal maturation of 62 boys less than 18 years old, both currently glucocorticoid treated (n = 44), previously treated (n = 6) and naïve (n = 12). The relationship between bone age, height and bone mineral density (BMD) Z-scores was explored.

Results

The participants in the glucocorticoid treated group were short in stature and puberty was delayed. Bone age was significantly delayed, and the delay increased with age and duration of treatment. The difference in height between glucocorticoid treated and naïve boys was no longer significant when height was corrected for delayed skeletal maturation. Mean BMD Z-scores fell below − 2 before 12 years of age in the glucocorticoid treated group, with scores significantly correlated with age, duration of treatment and pubertal development. When BMD Z-scores were corrected for by retarded bone age, the increase in BMD Z-scores was significant for all age groups.

Conclusion

Our results suggest that skeletal maturation should be assessed in the evaluation of short stature and bone health in GC treated boys with DMD, as failing to consider delayed bone age leads to underestimation of BMD Z-scores and potentially overestimation of fracture risk.

Invited Review: Pathology of pituitary neuroendocrine tumours: present status, modern diagnostic approach, controversies and future perspectives from a neuropathological and clinical standpoint

Neuroendocrine tumours of the adenohypophysis have traditionally been designated as pituitary adenomas to underline their usually indolent growth and lack of metastatic potential. However, they may demonstrate a huge spectrum of growth patterns and endocrine disturbances, some of them significantly affecting health and quality of life. To predict tumour growth, risk of postoperative recurrence and response to medical therapy in patients with pituitary neuroendocrine tumours is challenging. A thorough histopathological and immunohistochemical diagnostic work-up is an obligatory part of a multidisciplinary effort to precisely define the tumour type and assess prognostic and predictive factors on an individual basis. In this review, we have summarized the current status in the pathology in pituitary neuroendocrine tumours based on the selection of references from the PubMed database. We have presented possible diagnostic approaches according to the current pituitary cell lineage-based classification. The importance of recognizing histological subtypes with potentially aggressive behaviour and identification of prognostic and predictive tissue biomarkers have been highlighted. Controversies related to particular subtypes of pituitary tumours and a still limited prognostic impact of the current classification indicate the need for further refinement. Multidisciplinary approach including clinical, pathological and molecular genetic characterization will be essential for improved personalized therapy and the search for novel therapeutic targets in patients with pituitary neuroendocrine tumours.

Is there a need for an emergency card in hypoparathyroidism?

BACKGROUND

Patients with hypoparathyroidism are at risk of both hypocalcemic and hypercalcemic crisis. Patients report that health professionals do not always respond adequately in an acute situation. The extent and handling of severe hypo- and hypercalcemia in hypoparathyroidism is unknown.

AIMS

To outline the need for a medical emergency card for primary hypoparathyroidism.

METHOD

Postal survey amongst Norwegian and Swedish patients with chronic hypoparathyroidism of all causes. Altogether 455 invitations were sent (333 from Norway and 122 from Sweden).

RESULTS

Three hundred and thirty-six of 455 (74%) patients responded (253 from Norway and 83 from Sweden). The majority were women (79%), and the main cause was postsurgical hypoparathyroidism (66%). Overall 44% and 16% had been hospitalized at least once for hypo- or hypercalcemia, respectively. Eighty-seven per cent felt that an emergency card would be highly needed or useful. Amongst those hospitalized for hypocalcemia, 95% felt a card was needed compared to 90% amongst those hospitalized for hypercalcemia. Five per cent believed that a card would not be useful.

CONCLUSIONS

The majority answered that an acute card is highly needed or useful. Hospitalization for acute hypocalcemia was more common (44%) than for acute hypercalcemia (16%). As a result of this survey, an emergency card will be distributed in three European countries to test its utility.

Primary hyperparathyroidism: review and recommendations on evaluation, diagnosis, and management. A Canadian and international consensus

The purpose of this review is to assess the most recent evidence in the management of primary hyperparathyroidism (PHPT) and provide updated recommendations for its evaluation, diagnosis and treatment. A Medline search of "Hyperparathyroidism. Primary" was conducted and the literature with the highest levels of evidence were reviewed and used to formulate recommendations. PHPT is a common endocrine disorder usually discovered by routine biochemical screening. PHPT is defined as hypercalcemia with increased or inappropriately normal plasma parathyroid hormone (PTH). It is most commonly seen after the age of 50 years, with women predominating by three to fourfold. In countries with routine multichannel screening, PHPT is identified earlier and may be asymptomatic. Where biochemical testing is not routine, PHPT is more likely to present with skeletal complications, or nephrolithiasis. Parathyroidectomy (PTx) is indicated for those with symptomatic disease. For asymptomatic patients, recent guidelines have recommended criteria for surgery, however PTx can also be considered in those who do not meet criteria, and prefer surgery. Non-surgical therapies are available when surgery is not appropriate. This review presents the current state of the art in the diagnosis and management of PHPT and updates the Canadian Position paper on PHPT. An overview of the impact of PHPT on the skeleton and other target organs is presented with international consensus. Differences in the international presentation of this condition are also summarized.

Bilateral Femoral Head Dysplasia and Osteochondritis

Multiple epiphyseal dysplasia tarda (MEDT) and spondylo-epiphyseal dysplasisa tarda (SEDT) are genetically transmitted conditions affecting the hips, which may resemble bilateral Legg-Perthes disease (LPD). Misdiagnoses are not uncommon, with serious implications for treatment, prognosis and genetic counseling. An epidemiologic study of MEDT and SEDT in a well-defined population of 453 921 persons in Denmark was performed. A population prevalence of 0.7 per 100000 inhabitants with SEDT and 4.0 per 100 000 inhabitants with MEDT was found. Distinguishing features between MEDT, SEDT and bilateral LPD based on radiologic findings in the hips, other joints, and spine were ascertained. Bilateral LPD is always asymmetric, exhibits patches of increased density in the epiphyses and often metaphyseal cyst-like changes. No spinal lesion or affection of other joints is present, and the acetabula are normal. In MEDT and SEDT the capital femoral epiphyses are symmetrically flattened, fragmented and uniformly slightly sclerotic. Generalised platyspondyly is a constant finding in SEDT.

Preoperative octreotide therapy and surgery in acromegaly: associations between glucose homeostasis and treatment response

In acromegaly, high GH/IGF-1 levels associate with abnormal glucose metabolism. Somatostatin analogs (SSAs) reduce GH and IGF-1 but inhibit insulin secretion. We studied glucose homeostasis in de novo patients with acromegaly and changes in glucose metabolism after treatment with SSA and surgery. In this post hoc analysis from a randomized controlled trial, 55 de novo patients with acromegaly, not using antidiabetic medication, were included. Before surgery, 26 patients received SSAs for 6 months. HbA1c, fasting glucose, and oral glucose tolerance test were performed at baseline, after SSA pretreatment and at 3 months postoperative. Area under curve of glucose (AUC-G) was calculated. Glucose homeostasis was compared to baseline levels of GH and IGF-1, change after SSA pretreatment, and remission both after SSA pretreatment and 3 months postoperative. In de novo patients, IGF-1/GH levels did not associate with baseline glucose parameters. After SSA pretreatment, changes in GH/IGF-1 correlated positively to change in HbA1c levels (both p < 0.03). HbA1c, fasting glucose, and AUC-G increased significantly during SSA pretreatment in patients not achieving hormonal control (all p < 0.05) but did not change significantly in patients with normalized hormone levels. At 3 months postoperative, HbA1c, fasting glucose, and AUC-G were significantly reduced in both cured and not cured patients (all p < 0.05). To conclude, in de novo patients with acromegaly, disease activity did not correlate with glucose homeostasis. Surgical treatment of acromegaly improved glucose metabolism in both cured and not cured patients, while SSA pretreatment led to deterioration in glucose homeostasis in patients not achieving biochemical control.

Preoperative octreotide treatment of acromegaly: long-term results of a randomised controlled trial

OBJECTIVE

Randomised studies have demonstrated a beneficial effect of pre-surgical treatment with somatostatin analogues (SSA) in acromegaly when evaluated early postoperatively. The objective of this study was to evaluate the long-term surgical cure rates.

METHODS

Newly diagnosed patients were randomised to direct surgery (n=30) or 6-month pretreatment with octreotide LAR (n=32). The patients were evaluated 1 and 5 years postoperatively. Cure was defined as normal IGF1 levels and by normal IGF1 level combined with nadir GH <2 mU/l in an oral glucose tolerance test, all without additional post-operative treatment. A meta-analysis using the other published randomised study with long-term analyses on preoperative SSA treatment was performed.

RESULTS

The proportion of patients receiving post-operative acromegaly treatment was equal in the two groups. When using the combined criteria for cure, 10/26 (38%) macroadenomas were cured in the pretreatment group compared with 6/25 (24%) in the direct surgery group 1 year postoperatively (P=0.27), and 9/22 (41%) vs 6/22 (27%) macroadenomas, respectively, 5 years postoperatively (P=0.34). In the meta-analysis, 16/45 (36%) macroadenomas were cured using combined criteria in the pretreatment group vs 8/45 (18%) in the direct surgery group after 6-12 months (P=0.06), and 15/41 (37%) vs 8/42 (19%), respectively, in the long-term (P=0.08).

CONCLUSION

This study does not prove a beneficial effect of SSA pre-surgical treatment, but in the meta-analysis a trend towards significance can be claimed. A potential favourable, clinically relevant response cannot be excluded.

Celiac disease and risk of fracture in adults--a review

Patients with celiac disease (CD) have low bone mineral density. Evidence of increased fracture risk in these patients is conflicting, and the indication for bone mineral density screening of all adult CD patients is debated. Our aim was to review current published data on fractures in CD. Cross-sectional cohort studies and one case study were identified by searching Medline and Embase. Although the identified studies are heterogeneous and difficult to compare, the overall findings indicate a positive association between CD and risk of fracture. Adult patients with CD should be considered for bone densitometry in order to estimate fracture risk.

Two years of growth hormone treatment in adults with Prader-Willi syndrome do not improve the low BMD

BACKGROUND

Bone mineral density (BMD) in adult patients with Prader-Willi syndrome (PWS) might be low due to high bone turnover.

OBJECTIVES

The objective of the study was to investigate bone mass in a group of adult PWS subjects and study the effects of GH treatment on BMD and markers of bone turnover.

DESIGN

Forty-six adults with genetically verified PWS were randomized to GH or placebo for 12 months, followed by open prospective GH for 24 additional months. BMD at the lumbar spine (LS) L1-4, the total hip, and the total body was assessed by dual-energy x-ray absorptiometry at baseline and every 12th month thereafter. Markers of bone turnover were measured at baseline and at the end of the controlled study.

RESULTS

In this cohort of adult subjects with PWS, baseline BMD was reduced in all compartments compared with the reference (Z-scores). Men had lower Z-scores BMD than women in LS and total body (P < .05). With 12 months of GH, LS-BMD was significantly reduced compared with placebo. No changes in BMD were observed with continuous GH treatment for 24 months. The bone formation markers increased with GH therapy compared with placebo, whereas the resorption marker did not change.

CONCLUSIONS

Adult PWS subjects, especially the men, have low bone mass that was not improved with GH treatment for 2 years. Because PWS subjects are short, BMD might be underestimated and should be adjusted for. Further studies, with adequate GH and sex hormone replacement throughout puberty and early adult life, are needed to better characterize PWS.

A 1-year randomized, double-blind, placebo-controlled study of intravenous ibandronate on bone loss following renal transplantation

The clinical profile of ibandronate as add-on to calcitriol and calcium was studied in this double-blind, placebo-controlled trial of 129 renal transplant recipients with early stable renal function (≤ 28 days posttransplantation, GFR ≥ 30 mL/min). Patients were randomized to receive i.v. ibandronate 3 mg or i.v. placebo every 3 months for 12 months on top of oral calcitriol 0.25 mcg/day and calcium 500 mg b.i.d. At baseline, 10 weeks and 12 months bone mineral density (BMD) and biochemical markers of bone turnover were measured. The primary endpoint, relative change in BMD for the lumbar spine from baseline to 12 months was not different, +1.5% for ibandronate versus +0.5% for placebo (p = 0.28). Ibandronate demonstrated a significant improvement of BMD in total femur, +1.3% versus -0.5% (p = 0.01) and in the ultradistal radius, +0.6% versus -1.9% (p = 0.039). Bone formation markers were reduced by ibandronate, whereas the bone resorption marker, NTX, was reduced in both groups. Calcium and calcitriol supplementation alone showed an excellent efficacy and safety profile, virtually maintaining BMD without any loss over 12 months after renal transplantation, whereas adding ibandronate significantly improved BMD in total femur and ultradistal radius, and also suppressed biomarkers of bone turnover. Ibandronate was also well tolerated.

Correction of an unexpected increasing trend in glucose measurements during 7 years recruitment to a cohort study

OBJECTIVES

To study an unexpected, significant increase in glucose measurements during 7 year recruitment to a cohort study.

DESIGN AND METHODS

Measurements of quality control solutions and blood glucose in pregnant women were done by Accu-Chek Sensor glucometer. Time-trends were analysed by regression models and control charts.

RESULTS

Cohort measurements were de-trended by weighted linear regressions based on independent control values.

CONCLUSIONS

Biologically implausible trends in data can be corrected by using independent control values.

Increased serum and bone matrix levels of transforming growth factor {beta}1 in patients with GH deficiency in response to GH treatment

OBJECTIVE

Patients with adult onset GH deficiency (aoGHD) have secondary osteoporosis, which is reversed by long-term GH substitution. Transforming growth factor β1 (TGFβ1 or TGFB1) is abundant in bone tissue and could mediate some effects of GH/IGFs on bone. We investigated its regulation by GH/IGF1 in vivo and in vitro.

DESIGN AND METHODS

The effects of GH substitution (9-12 months, placebo controlled) on circulating and cortical bone matrix contents of TGFβ1 were investigated in patients with aoGHD. The effects of GH/IGF1 on TGFβ1 secretion in osteoblasts (hFOB), adipocytes, and THP-1 macrophages as well as the effects on release from platelets were investigated in vitro.

RESULTS

In vivo GH substitution increased TGFβ1 protein levels in cortical bone and serum. In vitro, GH/IGF1 stimulation induced a significant increase in TGFβ1 secretion in hFOB. In contrast, no major effect of GH/IGF1 on TGFβ1 was found in adipocytes and THP-1 macrophages. Finally, a minor modifying effect on SFLLRN-stimulated platelet release of TGFβ1 was observed in the presence of IGF1.

CONCLUSION

GH substitution increases TGFβ1 in vivo and in vitro, and this effect could contribute to improved bone metabolism during such therapy, potentially reflecting direct effect of GH/IGF1 on bone cells.

The importance of body composition and dry weight assessments in patients with chronic kidney disease

Chronic volume overload is the major cause of hypertension and other cardiovascular morbidity in dialysis patients. One of the most important goals of physicians who take care of patients with chronic renal failure is to obtain near euvolemia or "dry body weight" in order to maintain or normalize blood pressure and prevent further cardiovascular events. In clinical practice, exact estimation of dry weight in hemodialysis patients remains a major challenge. Alterations in body composition, particularly malnutrition, are common in patients receiving long-term hemodialysis and contribute to a high mortality rate. In contrast, obesity - a known risk factor for cardiovascular morbidity and mortality - is prevalent amongst kidney allograft recipients in - long term after renal transplantation. Several technological tools and biochemical markers for estimation of plasma volume and body composition are available for clinical use. Our aim was to highlight the importance of control of body fluid volume and body composition in patients with chronic kidney disease and to describe the different methods available for such measurements.

Favorable long-term effects of growth hormone replacement therapy on quality of life, bone metabolism, body composition and lipid levels in patients with adult-onset growth hormone deficiency

OBJECTIVE

The goal of growth hormone (GH) replacement is to improve quality of life (QoL) and prevent the long-term complications of GH deficiency (GHD). Thirty-nine patients with adult-onset GH deficiency (AOGHD) who had originally participated in a randomized placebo-controlled crossover study involving treatment with either GH or placebo for nine months were enrolled in an open, 33-month follow-up study of the effects on QoL as well as bone and metabolic parameters.

METHODS

GH replacement was dosed individually to obtain IGF-I concentrations that were within the upper part of the normal range for age (mean+1SD). The variables were assessed on five occasions during the study.

RESULTS

QoL, as assessed by the sum scores of HSCL-58, AGHDA, physical activity (KIMS question 11) and the dimension vitality in SF-36, improved. Markers of bone formation and resorption remained increased throughout the study period. Bone mineral area (BMA), bone mineral content (BMC) and bone mineral density (BMD) increased in both the lumbar (L2-L4) spine and total body. BMC and BMD increased in the femur. Hypogonadal women however, showed reduced bone mass during the study period. The changes in body fat mass (BFM) and lean body mass (LBM) were sustained throughout the long-term treatment (BFM -2.18 (+/-4.87) kg LBM by 2.01(+/-3.25) kg). Low-density lipoprotein cholesterol (LDL-C) levels were reduced by 0.6 (+/-1.1) mmol/l, and high-density lipoprotein cholesterol (HDL-C) levels increased by 0.2 (+/-0.3) mmol/l. No changes were observed in body weight, fasting total cholesterol, triglycerides, HbA1c and plasma glucose. Mean fasting insulin levels increased significantly from 110 pmol/l to 159 pmol/l, p<0.02.

CONCLUSION

Long-term replacement of growth hormone in patients with AOGHD induces favorable effects on QoL as well as bone and metabolic parameters. An increase in insulin levels is also noteworthy.

Beta cell function after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention

OBJECTIVE

The effects of various weight loss strategies on pancreatic beta cell function remain unclear. We aimed to compare the effect of intensive lifestyle intervention (ILI) and Roux-en-Y gastric bypass surgery (RYGB) on beta cell function.

DESIGN

One year controlled clinical trial (ClinicalTrials.gov identifier NCT00273104).

METHODS

One hundred and nineteen morbidly obese participants without known diabetes from the MOBIL study (mean (s.d.) age 43.6 (10.8) years, body mass index (BMI) 45.5 (5.6) kg/m², 84 women) were allocated to RYGB (n = 64) or ILI (n = 55). The patients underwent repeated oral glucose tolerance tests (OGTTs) and were categorised as having either normal (NGT) or abnormal glucose tolerance (AGT). Twenty-nine normal-weight subjects with NGT (age 42.6 (8.7) years, BMI 22.6 (1.5) kg/m², 19 women) served as controls. OGTT-based indices of beta cell function were calculated.

RESULTS

One year weight reduction was 30% (8) after RYGB and 9% (10) after ILI (P < 0.001). Disposition index (DI) increased in all treatment groups (all P<0.05), although more in the surgery groups (both P < 0.001). Stimulated proinsulin-to-insulin (PI/I) ratio decreased in both surgery groups (both P < 0.001), but to a greater extent in the surgery group with AGT at baseline (P < 0.001). Post surgery, patients with NGT at baseline had higher DI and lower stimulated PI/I ratio than controls (both P < 0.027).

CONCLUSIONS

Gastric bypass surgery improved beta cell function to a significantly greater extent than ILI. Supra-physiological insulin secretion and proinsulin processing may indicate excessive beta cell function after gastric bypass surgery.

Osteoclast activity and subtypes as a function of physiology and pathology--implications for future treatments of osteoporosis

Osteoclasts have traditionally been associated exclusively with catabolic functions that are a prerequisite for bone resorption. However, emerging data suggest that osteoclasts also carry out functions that are important for optimal bone formation and bone quality. Moreover, recent findings indicate that osteoclasts have different subtypes depending on their location, genotype, and possibly in response to drug intervention. The aim of the current review is to describe the subtypes of osteoclasts in four different settings: 1) physiological, in relation to turnover of different bone types; 2) pathological, as exemplified by monogenomic disorders; 3) pathological, as identified by different disorders; and 4) in drug-induced situations. The profiles of these subtypes strongly suggest that these osteoclasts belong to a heterogeneous cell population, namely, a diverse macrophage-associated cell type with bone catabolic and anabolic functions that are dependent on both local and systemic parameters. Further insight into these osteoclast subtypes may be important for understanding cell-cell communication in the bone microenvironment, treatment effects, and ultimately bone quality.

Obesity-related cardiovascular risk factors after weight loss: a clinical trial comparing gastric bypass surgery and intensive lifestyle intervention

OBJECTIVE

Weight reduction improves several obesity-related health conditions. We aimed to compare the effect of bariatric surgery and comprehensive lifestyle intervention on type 2 diabetes and obesity-related cardiovascular risk factors.

DESIGN

One-year controlled clinical trial (ClinicalTrials.gov identifier NCT00273104).

METHODS

Morbidly obese subjects (19-66 years, mean (s.d.) body mass index 45.1 kg/m(2) (5.6), 103 women) were treated with either Roux-en-Y gastric bypass surgery (n=80) or intensive lifestyle intervention at a rehabilitation centre (n=66). The dropout rate within both groups was 5%.

RESULTS

Among the 76 completers in the surgery group and the 63 completers in the lifestyle group, mean (s.d.) 1-year weight loss was 30% (8) and 8% (9) respectively. Beneficial effects on glucose metabolism, blood pressure, lipids and low-grade inflammation were observed in both groups. Remission rates of type 2 diabetes and hypertension were significantly higher in the surgery group than the lifestyle intervention group; 70 vs 33%, P=0.027, and 49 vs 23%, P=0.016. The improvements in glycaemic control and blood pressure were mediated by weight reduction. The surgery group experienced a significantly greater reduction in the prevalence of metabolic syndrome, albuminuria and electrocardiographic left ventricular hypertrophy than the lifestyle group. Gastrointestinal symptoms and symptomatic postprandial hypoglycaemia developed more frequently after gastric bypass surgery than after lifestyle intervention. There were no deaths.

CONCLUSIONS

Type 2 diabetes and obesity-related cardiovascular risk factors were improved after both treatment strategies. However, the improvements were greatest in those patients treated with gastric bypass surgery.

Overweight is associated with impaired beta-cell function during pregnancy: a longitudinal study of 553 normal pregnancies

OBJECTIVE

To monitor beta-cell function and insulin sensitivity longitudinally in a large cohort of pregnant women to elucidate mechanisms that influence glycemic control in pregnancy.

DESIGN AND METHODS

Five hundred and fifty-three pregnant Scandinavian women underwent 75 g oral glucose tolerance test (OGTT) at weeks 14-16 and 30-32. Insulin sensitivity (Matsuda index) and beta-cell function (ratio of AUC(insulin) to AUC(glucose), AUC(ins/glc)) were calculated from 520 complete tests, and subsequently beta-cell function was adjusted for insulin sensitivity, rendering an oral disposition index (DI(o)).

RESULTS

Eleven women (2.1%) had gestational diabetes mellitus (GDM1) at weeks 14-16, and 49 (9.4%) at weeks 30-32 (GDM2), which is higher than that previously reported in this region. In the subdivision of OGTT, more overweight (body mass index>25) was found in glucose-intolerant groups (glucose-tolerant women (normal glucose tolerance, NGT) 38 versus GDM2 women 58 and GDM1 women 82%, P<0.005). In early pregnancy, insulin sensitivity was lowest in GDM1, intermediate in GDM2, and highest in NGT. In late pregnancy, insulin sensitivity decreased in all groups, most in gestational diabetes. beta-cell function demonstrated minor shifts during pregnancy, but when adjusted for decreasing insulin sensitivity, DI(o) levels fell by 40% (P<0.001). DI(o) was significantly attenuated relative to glucose intolerance (GDM1 25% and GDM2 53%) during pregnancy. In overweight women, DI(o) levels were lower throughout pregnancy (P<0.001 versus normal weight women), this reduction was significant (P<0.01) in both NGT (21-25%) and GDM2 subjects (26-49%).

CONCLUSION

beta-cell function adjusted for insulin sensitivity (DI(o)) deteriorated during pregnancy in both glucose-tolerant and glucose-intolerant women. The failure to compensate the decrease in insulin sensitivity was accentuated in overweight women.

Biochemical evidence of disturbed bone metabolism and calcium homeostasis in two types of autosomal dominant osteopetrosis

Biochemical markers of bone resorption and bone formation were measured in 14 patients with autosomal dominant osteopetrosis, and compared with age- and sex-matched controls. There were eight patients with the radiological type I characterized by diffuse, symmetrical osteosclerosis with pronounced sclerosis of the skull and enlarged thickness of the cranial vault, and six patients with type II characterized by diffuse, symmetrical osteosclerosis, "Rugger-Jersey spine" and "endobones" (bone within a bone) in the pelvis. Serum levels of alkaline phosphatase and osteocalcin in types I and II did not differ from controls indicating normal bone formation. However, a significantly decreased fasting renal excretion of phosphate and hydroxyproline in both types compared with normal controls, suggests a reduced bone resorption. Serum levels of parathyroid hormone (PTH), albumin-corrected calcium, phosphate, and acid phosphatase were normal in type I. In type II serum levels of albumin-corrected calcium and PTH were significantly increased (p less than 0.05 and p less than 0.01). The level of acid phosphatase was markedly increased in this type (p less than 0.01). These findings suggest differences between the two types in calcium homeostasis and bone metabolism, and thus corroborate the evidence that the two radiological types reflect two different disorders of bone resorption.

Retinol-binding protein-4 is not strongly associated with insulin sensitivity in normal pregnancies

OBJECTIVE

Recently, experimental and clinical studies suggest that retinol-binding protein-4 (RBP4) may provide a link between obesity and insulin resistance. However, no previous studies have investigated the impact of circulating RBP4 on measures of insulin resistance in normal pregnant women, and the objective of this study is to measure serum RBP4 in early and late pregnancy and relate these to measures of insulin resistance and secretion controlling for changes in fat mass.

DESIGN AND METHODS

Samples were obtained during oral glucose tolerance test (OGTT) from 44 normal pregnancies at weeks 14-16 and 30-32. Measures of fat mass were body mass index (BMI) and leptin while insulin sensitivity and secretion were predicted from OGTT. Leptin and RPB4 were measured by immunoassay.

RESULTS

Insulin sensitivity decreased during the course of pregnancy. Insulin sensitivity and secretion were best explained by BMI and circulating leptin, but not RBP4, both in early and late pregnancy. However, a marked increase in fasting RBP4 from early to late pregnancy was observed, and this change was associated with a decline in insulin sensitivity. A marked increase in RBP4 was found during OGTT at weeks 14-16 with an opposite temporal course at weeks 30-32.

CONCLUSION

The increased fat mass and insulin resistance during normal pregnancy was best explained by measures of fat mass. However, the increase in RBP4 from early to late pregnancy, associated with a decline in insulin sensitivity, potentially indicates interactions with glucose metabolism.

Biochemical markers for cardiovascular risk following treatment in endogenous Cushing's syndrome

OBJECTIVE

Cardiovascular disease has been reported to be more common in patients with endogenous Cushing's syndrome (CS) compared to the normal population. In addition to altered lipid profile, inflammation seems to play an important pathogenic role in atherogenesis, but the role of inflammation in CS-associated cardiovascular disease is still not clear. To further elucidate these issues we measured several markers of inflammation in CS patients at baseline and following operative treatment and potential cure.

SUBJECTS

Twenty-eight CS patients (22 women, 6 men) were included in the study and 21 of these patients (15 women, 6 men) were also followed longitudinally for a mean 33 months (range 5-69 months) after operative treatment. For comparison, blood samples were also collected from 24 healthy controls (21 women, 3 men).

RESULTS

We show a distinct cytokine profile in CS patients before and after operative treatment. Thus, while interleukin (IL)-8 and osteoprotegerin (OPG) were significantly increased in CS patients before operation and fell during follow-up, levels of C-reactive protein (CRP) and soluble intracellular adhesion molecule 1 (sICAM) were significantly decreased at baseline, reaching normal levels after operation. While soluble CD40 ligand was within normal limit at baseline, this marker of platelet-mediated inflammation was markedly elevated during follow-up.

CONCLUSIONS

Our findings suggest a complex interaction between CS and inflammation. In particular, the raised levels of IL-8 and OPG in CS patients, despite glucocorticoid excess, may represent an inflammatory and pro-atherogenic phenotype. However, the clinical relevance of these findings will have to be clarified.

No associations between OPG gene polymorphisms or serum levels and measures of osteoporosis in elderly Australian women

Bone mass is the single most important risk factor for osteoporotic fractures in the elderly and is mainly influenced by genetic factors accounting for 40-75% of the inter-individual variation. Critical for the bone remodeling process is the balance between the newly discovered members of the tumor necrosis factor ligand and receptor superfamilies, osteoprotegerin (OPG) and receptor activator of nuclear factor-kappaB ligand, which mediate the effects of many upstream regulators of bone metabolism. In the present study, we evaluated the impact of sequence variations in the OPG gene on bone mass, bone-related biochemistry including serum OPG and fracture frequency in elderly Australian women. A total of 1101 women were genotyped for 3 different single nucleotide polymorphisms (SNP) within the OPG gene (G1181C, T950C and A163G). The effects of these SNPs and serum OPG on calcaneal quantitative ultrasound measurements, osteodensitometry of the hip and bone-related biochemistry were examined. We found no significant relationship between sequence variations in the OPG gene or serum OPG and bone mass, bone-related biochemistry or fracture frequency. Our findings confirm some recent publications investigating the same SNPs but diverge from others, indicating that generalization of the relationships found in this type of study must be done with caution and signify the importance of determining associations between polymorphisms and osteoporosis in different ethnic groups.

Serum GH and IGF-I are significant determinants of bone turnover but not bone mineral density in active acromegaly: a prospective study of more than 70 consecutive patients

OBJECTIVE

Acromegaly is characterized by a persistent hypersecretion of GH and provides information on long-term effects of GH on bone metabolism. The aim of this study was to examine the effect of gonadal status and disease activity on bone metabolism in active acromegaly.

METHODS

Seventy-three consecutive patients with active acromegaly: 40 women and 33 men (50 +/- 13 (mean +/- s.d.) and 49 +/- 10 years respectively) were evaluated and compared with age-, sex-, and body mass index (BMI)-matched controls by X-ray absorptiometry and biochemical analysis (markers of disease activity and bone turnover).

RESULTS

We found that bone turnover, as evaluated by biochemical bone markers, is coupled and markedly increased in relation to disease activity in active acromegaly. Acromegalic women, but not men, were characterized by an increased bone area and slightly decreased bone mineral content resulting in significantly decreased bone mineral density (BMD) in the ultradistal radius, proximal radius, and total body. No differences in bone turnover or BMD were found between eu-and hypogonadal subjects. Multivariate analysis identified age, BMI, and gender as independent predictors of total BMD in acromegaly.

CONCLUSION

Our study demonstrates a decreased total body BMD in women, not men, with active acromegaly, regardless of gonadal status or disease activity. Bone turnover is markedly increased in relation to disease activity, possibly counteracting the anabolic effects of excess GH/IGF-I in these subjects. We suggest more focus on biomechanical analyses when investigating endocrine disorders affecting bone size and distribution between compartments.

Maternal anthropometric and metabolic factors in the first half of pregnancy and risk of neonatal macrosomia in term pregnancies. A prospective study

OBJECTIVE

The prevalence of maternal overweight and fetal macrosomia is increasing. Fetal macrosomia is associated with increased risk of maternal and neonatal complications. The objective of the present study was to investigate if maternal metabolic parameters associated with maternal overweight were independent determinants of macrosomia (birth weight > 4500 g or above the 95 percentile of the z-score for standardized birth weight).

DESIGN

Prospective population based cohort study of 2050 pregnancies and nested case control study.

METHODS

Outcome measures were adjusted risks for macrosomia in relation to early second trimester maternal serum lipids, glucose and insulin (cohort study) and leptin and insulin-like growth factor (73 cases and 146 matched controls).

RESULTS

Gestational diabetes was not independently associated with fetal macrosomia. First trimester body mass index (BMI), gestational weight gain and placental weight were associated with macrosomia. High serum insulin and non-high density lipoprotein (HDL)-cholesterol and low serum HDL-cholesterol were associated with increased risk of macrosomia independent of BMI, weight gain, placental weight and gestational diabetes. Slim women with macrosomic infants had higher insulin compared with those with normal weight infants. This relation was not found among obese women. Leptin was not associated with macrosomia after adjusting for maternal BMI.

CONCLUSIONS

Blood parameters known to be associated with the metabolic syndrome were risk factors for macrosomia independent of maternal BMI.

LRP5 gene polymorphisms predict bone mass and incident fractures in elderly Australian women

Postmenopausal osteoporosis and bone mass are influenced by multiple factors including genetic variation. The importance of LDL receptor-related protein 5 (LRP5) for the regulation of bone mass has recently been established, where loss of function mutations is followed by severe osteoporosis and gain of function is related to increased bone mass. The aim of this study was to evaluate the role of polymorphisms in the LRP5 gene in regulating bone mass and influencing prospective fracture frequency in a well-described, large cohort of normal, ambulatory Australian women. A total of 1301 women were genotyped for seven different single nucleotide polymorphisms (SNPs) within the LRP5 gene of which five were potentially informative. The effects of these gene polymorphisms on calcaneal quantitative ultrasound measurements (QUS), osteodensitometry of the hip and bone-related biochemistry was examined. One SNP located in exon 15 was found to be associated with fracture rate and bone mineral density. Homozygosity for the less frequent allele of c.3357 A > G was associated with significant reduction in bone mass at most femoral sites. The subjects with the GG genotype, compared to the AA/AG genotypes showed a significant reduction in BUA and total hip, femoral neck and trochanter BMD (1.5% P = 0.032; 2.7% P = 0.047; 3.6% P = 0.008; 3.1% P = 0.050, respectively). In the 5-year follow-up period, 227 subjects experienced a total of 290 radiologically confirmed fractures. The incident fracture rate was significantly increased in subjects homozygous for the GG polymorphism (RR of fracture = 1.61, 95% CI [1.06-2.45], P = 0.027). After adjusting for total hip BMD, the fracture rate was still increased (RR = 1.67 [1.02-2.78], P = 0.045), indicating factors other than bone mass are of importance for bone strength. In conclusion, genetic variation in LRP5 seems to be of importance for regulation of bone mass and osteoporotic fractures.

Calcium-sensing receptor gene polymorphism A986S does not predict serum calcium level, bone mineral density, calcaneal ultrasound indices, or fracture rate in a large cohort of elderly women

Postmenopausal osteoporosis is a complex and heterogeneous disease influenced by multiple factors and related to peak bone mass achieved in early adult life, followed by a subsequent continuous bone loss. Genetic variance and polymorphisms have been shown to be of clinical significance for osteoporotic fragility fractures. Previous studies have related variations in the calcium sensor receptor (CASR) gene to circulating Ca levels and bone mass in young women and adolescent girls. The aim of this study was to investigate the impact of the A986S polymorphism of the CASR gene on calcium homeostasis and bone metabolism in elderly women. We studied the distribution of the A986S polymorphism in a large cohort of 1252 ambulatory Australian women in relation to biochemical markers of bone metabolism, bone mass evaluated by quantitative ultrasound measurements (QUS) and DXA of the hip, prevalent and 36-month incident fracture data. No effect of the polymorphism was found on circulating calcium level, renal Ca excretion, or biochemical markers of bone turnover. Moreover, A986S was not associated with bone mass or prevalent or incident fractures. Power calculations revealed that a difference in circulating calcium levels of 0.05 mmol/l, a difference in DXA bone density of 24 mg, and a 1.6-fold difference in fracture rate could have been detected with a power of 80%. In conclusion, in a large cohort of elderly women the A986S polymorphism of the CASR gene was not found to be significant for calcium homeostasis or bone mass. It is questioned whether the polymorphism has any clinical significance for postmenopausal osteoporosis.

Growth hormone substitution increases gene expression of members of the IGF family in cortical bone from women with adult onset growth hormone deficiency--relationship with bone turn-over

OBJECTIVE

To investigate the effects of growth hormone (GH) replacement therapy on bone matrix gene expression of insulin-like growth factors (IGFs) and markers of bone metabolism in women with adult-onset GH deficiency (GHD).

DESIGN AND METHODS

Nineteen women, mean age 45 (range 24-56) years, were included in a double-blind, placebo-controlled parallel group study for 12 months. Biochemical markers were measured at baseline, 6 and 12 months. Bone biopsies were obtained and BMD was measured at baseline and after 12 months.

RESULTS

Maximum responses were observed after 6 and 12 months, for bone resorptive and bone formative markers respectively. GH therapy enhanced gene expression in cortical bone of IGFs, GH-and calcitonin-receptor (CR) and osteoprotegerin (OPG), however with the most pronounced effects on CR and IGF-I. Changes in IGF-I gene expression during longitudinal follow-up were significantly correlated with changes in both circulating IGF-I (r = 0.82, p < 0.05), changes in markers of enhanced osteoclastic activity, measured both locally in bone (CR, r = 0.87, p < 0.01) and in serum (CTX-I, r = 0.86, p < 0.05), as well as serum bone ALP (r = 0.96, p < 0.01).

CONCLUSIONS

This study indicates that both liver- and bone-derived IGF-I may be significant in mediating the effects of GH on bone metabolism in humans.

Interleukin-1 receptor antagonist is associated with fat distribution in endogenous Cushing's syndrome: a longitudinal study

The weight gain and visceral obesity associated with Cushing's syndrome (CS) has been linked to elevated plasma leptin levels, although the mechanism behind a central leptin resistance in these patients is unknown. Several studies describe interactions among the hypothalamic-pituitary-adrenal axis, leptin, and the IL-1 system. To investigate these interactions, we have evaluated changes in regional fat distribution, by DEXA, and the role of circulating cortisol, leptin, IL-1beta, and IL-1 receptor antagonist (IL-1Ra), in relation to these changes, in 27 (19 DEXA; 27 serum measurements) patients with CS, before and after surgical treatment (mean follow-up, 31 months; range, 5-80), and compared them with measurements of age-, sex-, and body mass index-matched healthy controls (also obtained longitudinally). We found that surgical treatment caused a decrease in all fat parameters, without changing lean body mass, and these changes were significantly larger than the so-called natural changes occurring in control subjects. These changes in CS patients were paralleled by decreases in cortisol, leptin, and IL-1Ra, whereas IL-1beta increased. Stepwise linear regression showed that serum IL-1Ra was strongly associated with regional fat distribution, and especially truncal fat mass, both at baseline and during treatment. In conclusion, the present study shows that treatment significantly changes body composition in CS patients by decreasing fat mass, especially in the truncal region, without major effects on lean body mass. We also show that circulating IL-1Ra is strongly associated with these changes, signifying a relationship among the hypothalamic-pituitary-adrenal axis, IL-1 system, and regional fat distribution in these patients.

Secondary Osteoporosis in Liver Transplant Recipients: a Longitudinal Study in Patients With and Without Cholestatic Liver Disease

BACKGROUND

Metabolic bone disease is one of the major long-term complications in liver transplant recipients, but it remains unclear which patients are at highest risk for developing severe bone disease following transplantation.

METHODS

A total of 46 consecutive, adult patients with chronic liver disease accepted for a liver transplantation waiting list were prospectively included in the study. The patients were classified into two groups: group A-chronic cholestatic liver disease (n = 28), and group B-chronic non-cholestatic liver disease (n = 18). Bone mineral density (BMD) was measured at acceptance for the waiting list and at 3, 12 and 36 months following transplantation. Markers of bone turnover (serum-bone specific alkaline phosphatases (bALP), s-osteocalcin, s-l-collagen-C-terminal telopeptide (1-CTP) and urine N-terminal telopeptides u-Ntx) were measured at acceptance and at 3, 6, 12, 24 and 36 months following transplantation. BMD and markers of bone turnover were compared with similar values in a matched control group of 42 healthy individuals.

RESULTS

BMD decreased significantly during the early post-transplantation period (median bone loss femoral neck (FN) 3 months post-transplant 8.5%). BMD levels declined slightly from 3 to 12 months following transplantation and increased thereafter. The relative bone loss was greatest among group B patients (relative bone loss FN 3 months post-transplant: group A, 8% versus group B, 13%; P = 0.04). At 36 months, 8/17 group A and 2/9 group B patients had BMD levels that exceeded the pretransplant levels (P = 0.12). The early bone loss was positively correlated with an increase in resorption markers (s-1-CTP and u-Ntx). Group B had higher levels of both s-1-CTP and u-Ntx at 3 and 6 months post-transplant than group A patients (P = 0.03). Bone formation markers increased slowly from 6 months post-transplant and onwards. Relative bone loss was positively correlated to total glucocorticoid dose during the first 3 months post-transplant. There were no differences in BMD between patients receiving tacrolimus versus those receiving'cyclosporin A.

CONCLUSION

Bone loss following liver transplantation is considerable in patients with both cholestatic and non-cholestatic liver disease, the first group has the poorest starting-point while the latter group has the greatest bone loss following transplantation. Bone loss is closely correlated with biochemical markers of bone resorption and total dose of glucocorticoids given post-transplant.

Secondary osteoporosis in liver transplant recipients: a longitudinal study in patients with and without cholestatic liver disease

BACKGROUND

Metabolic bone disease is one of the major long-term complications in liver transplant recipients, but it remains unclear which patients are at highest risk for developing severe bone disease following transplantation.

METHODS

A total of 46 consecutive, adult patients with chronic liver disease accepted for a liver transplantation waiting list were prospectively included in the study. The patients were classified into two groups: group A--chronic cholestatic liver disease (n = 28), and group B--chronic non-cholestatic liver disease (n = 18). Bone mineral density (BMD) was measured at acceptance for the waiting list and at 3, 12 and 36 months following transplantation. Markers of bone turnover (serum-bone specific alkaline phosphatases (bALP), s-osteocalcin, s-1-collagen-C-terminal telopeptide (1-CTP) and urine N-terminal telopeptides u-Ntx) were measured at acceptance and at 3, 6, 12, 24 and 36 months following transplantation. BMD and markers of bone turnover were compared with similar values in a matched control group of 42 healthy individuals.

RESULTS

BMD decreased significantly during the early post-transplantation period (median bone loss femoral neck (FN) 3 months post-transplant 8.5%). BMD levels declined slightly from 3 to 12 months following transplantation and increased thereafter. The relative bone loss was greatest among group B patients (relative bone loss FN 3 months post-transplant: group A, 8% versus group B, 13%; P = 0.04). At 36 months, 8/17 group A and 2/9 group B patients had BMD levels that exceeded the pretransplant levels (P = 0.12). The early bone loss was positively correlated with an increase in resorption markers (s-1-CTP and u-Ntx). Group B had higher levels of both s-1-CTP and u-Ntx at 3 and 6 months post-transplant than group A patients (P = 0.03). Bone formation markers increased slowly from 6 months post-transplant and onwards. Relative bone loss was positively correlated to total glucocorticoid dose during the first 3 months post-transplant. There were no differences in BMD between patients receiving tacrolimus versus those receiving cyclosporin A.

CONCLUSION

Bone loss following liver transplantation is considerable in patients with both cholestatic and non-cholestatic liver disease, the first group has the poorest starting-point while the latter group has the greatest bone loss following transplantation. Bone loss is closely correlated with biochemical markers of bone resorption and total dose of glucocorticoids given post-transplant.

Effects of 12 months of GH treatment on cortical and trabecular bone content of IGFs and OPG in adults with acquired GH deficiency: a double-blind, randomized, placebo-controlled study

To investigate the effects of 12 months of GH treatment on cortical and trabecular bone content of IGFs, iliac crest bone biopsies were obtained from 25 patients with GH deficiency (9 women and 16 men; ages, 21-61 yr; mean, 46 yr) who were randomized to sc injections with GH (2 IU/m(2).d) or placebo for 12 months. Levels of IGF-I, IGF-II, IGF binding protein (IGFBP)-3, IGFBP-5, osteocalcin, OPG, RANKL, and total protein were determined in extracts obtained after EDTA and guanidine hydrochloride extraction. Calcium was determined after HCl hydrolysis. Comparing changes during GH or placebo treatment, significant increases were observed during GH substitution for cortical and trabecular bone content of IGF-I [mean difference vs. placebo (mean +/- SEM), 97 +/- 30 and 72 +/- 38%] and OPG (mean difference vs. placebo, 109 +/- 59 and 51 +/- 19%). Also, a significant decline was found for cortical osteocalcin (mean difference vs. placebo, -49 +/- 22%) during GH treatment. In conclusion, our results indicate that long-term GH treatment increases the accumulation of IGF-I and OPG in cortical and trabecular bone in patients with GH deficiency, and this may in turn lead to an increase in bone mass and improved skeletal biomechanical competence.

Parathyroid adenoma in a subject with familial hypocalciuric hypercalcemia: coincidence or causality?

A middle-aged woman presented with a history of constipation, easy fatigue, depressive mood, lassitude, polydipsia, and polyuria. The patient posed a challenging diagnostic dilemma due to the presence of persistent severe hypercalcemia and relative lack of clinically manifested symptoms. Clinical, biochemical, and genetic examinations confirmed the diagnosis of familial hypocalciuric hypercalcemia as a result of C562Y calcium-sensing receptor mutation, and a coexisting parathyroid adenoma. After adenectomy, the patient's clinical situation improved markedly, and a modest equilibrium hypercalcemia persisted. This case presents an unusual combination of two relatively common endocrine disorders.

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.

Increased serum osteoprotegerin in disorders characterized by persistent immune activation or glucocorticoid excess--possible role in bone homeostasis

OBJECTIVE

To investigate the possible role of osteoprotegerin (OPG) in bone metabolism in humans by measuring serum levels of OPG in five well-characterized patient populations with known or suspected pathology in bone homeostasis, but with differences in the pathogenesis of these disturbances.

DESIGN

The study comprised 34 patients with Cushing's syndrome (CS), 24 acromegalic patients, 16 patients with growth hormone deficiency (GHD), 29 HIV-infected patients, 25 patients with common variable immunodeficiency (CVI) and 59 age- and sex-matched healthy controls (CTR).

METHODS

Serum levels of tumor necrosis factor (TNF)-alpha, OPG, C-terminal telopeptides of Type-I collagen (CTX-I) and osteocalcin were determined in all study subjects as well as cortisol (CS and CTR) and IGF-I (acromegaly, GHD and CTR).

RESULTS

OPG levels were significantly elevated in both CVI (median increase approximately 32%, P < 0.05) and HIV-infected patients with especially high levels in the latter group ( approximately 52%, P < 0.001), significantly correlated with increased TNFalpha levels (r = 0.47, P < 0.02). Also CS patients had elevated serum OPG ( approximately 24%, P < 0.01), significantly correlated with increased serum cortisol (r = 0.35, P < 0.05). In contrast, OPG levels in acromegalic and GHD patients were not different from healthy controls. No relationships were found between OPG levels and CTX-I or osteocalcin.

CONCLUSIONS

These findings suggest that enhanced OPG levels may be a compensatory response to enhanced osteoclast activity or negative bone remodeling balance in some conditions, but may also be a parameter of enhanced activity in the OPG system possibly correlated to enhanced activity of other members of the TNF family.

Albers-Schönberg disease (autosomal dominant osteopetrosis, type II) results from mutations in the ClCN7 chloride channel gene

Albers-Schönberg disease, or autosomal dominant osteopetrosis, type II (ADO II), is the most common form of osteopetrosis, a group of conditions characterized by an increased skeletal mass due to impaired bone and cartilage resorption. Following the assignment of the gene causing ADO II to chromosome 16p13.3, we now report seven different mutations in the gene encoding the ClCN7 chloride channel in all 12 ADO II families analysed. Additionally, a patient with the severe, autosomal recessive, infantile form of osteopetrosis (ARO) was identified as being homozygous for a ClCN7 mutation. From genotype-phenotype correlations, it seems that ADO II reflects a dominant negative effect, whereas loss-of-function mutations in ClCN7 do not cause abnormalities in heterozygous individuals. Because some ARO patients have mutations in both copies of the ClCN7 gene, ADO II is allelic with a subset of ARO cases.

Mapping of autosomal dominant osteopetrosis type II (Albers-Schönberg disease) to chromosome 16p13.3

The osteopetroses are a heterogeneous group of conditions characterized by a bone-density increase due to impaired bone resorption. As well as the two or more autosomal recessive types, two autosomal dominant forms of osteopetrosis, differentiated by clinical and radiological signs, are described. Autosomal dominant osteopetrosis (ADO) type II, also known as "Albers-Schönberg disease," is characterized by sclerosis, predominantly involving the spine (vertebral end-plate thickening, or Rugger-Jersey spine), the pelvis ("bone-within-bone" structures), and the skull base. An increased fracture rate can be observed in these patients. By linkage analysis, the presence, on chromosome 1p21, of a gene causing ADO type II was previously suggested. However, analysis of further families with ADO type II indicated genetic heterogeneity within ADO type II, with the chromosome 1p21 locus being only a minor locus. We now perform a genomewide linkage scan of a French extended family with ADO type II, which allows us to localize an ADO type II gene on chromosome 16p13.3. Analysis of microsatellite markers in five further families with ADO type II could not exclude this chromosomal region. A summed maximum LOD score of 12.70 was generated with marker D16S3027, at a recombination fraction (straight theta) of 0. On the basis of the key recombinants in the families, a candidate region of 8.4 cM could be delineated, flanked by marker D16S521, on distal side, and marker D16S423, on the proximal side. Surprisingly, one of the families analyzed is the Danish family previously suggested to have linkage to chromosome 1p21. Linkage to chromosome 16p13.3 clearly cannot be excluded in this family, since a maximum LOD score of 4.21 at theta=0 is generated with marker D16S3027. Because at present no other family with ADO type II has proved to have linkage to chromosome 1p21, we consider the most likely localization of the disease-causing gene in this family to be to chromosome 16p13.3. This thus reopens the possibility that ADO type II is genetically homogeneous because of a single gene on chromosome 16p13.3.

Leptin response to endogenous acute stress is independent of pituitary function

There are close interactions between the adipocyte-derived hormone, leptin, and the anterior pituitary, especially the hypothalamic-pituitary-adrenal (HPA) axis. We investigated the relationship between the sympathetic adrenergic system and serum leptin levels, dependent on the function of anterior pituitary hormone axes, in 27 patients without a history of a hormone-secreting pituitary adenoma or other underlying endocrine disease. Based on responses in a routine insulin hypoglycemia test (ITT), the patients were classified as hypopituitary (HP; n=15), growth hormone deficient (GHD; n=6) or controls (CTR; 6 patients with normal responses). Nadir plasma glucose was 1.5+/-0.1 mmol/l at the time of maximum hypoglycemia. Each group had a significant increase in plasma epinephrine; however the magnitude of change was significantly higher in GHD (6.066+/-1.633 nmol/l) compared with HP patients (1.781+/-0.492 nmol/l) (P<0.01). The rise in norepinephrine was delayed (60 min) in the HP and CTR groups. However, in GHD patients there was a considerable increase at the time of hypoglycemia which was significantly different from HP (P<0.001) and CTR (P<0.05) patients. The increase in catecholamines was followed by a quick and significant decrease in serum leptin levels 45 min after an i.v. bolus injection of insulin in HP patients (-4.7+/-2.5%, P<0.05), which was significantly sustained after 60 min (-5.6+/-2.5%, P<0.05). In CTR patients there was a significant decrease in serum leptin levels 60 min after i.v. insulin (-14.4+/-6.9%, P<0.05), while no significant response was observed in the GHD group, although 5 of 6 patients had decreased levels at 45 and 60 min. No differences between the groups were found by ANOVA. In conclusion, an acute increase in endogenous circulating catecholamines is associated with a quick decrease in serum leptin levels. Intact anterior pituitary function seems not to be essential for this hitherto poorly understood mechanism.

Increased levels of biochemical markers of bone turnover in relation to persistent immune activation in common variable immunodeficiency

BACKGROUND

Based on the involvement of cytokines and growth factors in bone homeostasis, we hypothesised that patients with common variable immunodeficiency (CVI), characterised by persistent immune activation in vivo, may have disturbed bone metabolism as evaluated by biochemical markers of bone turnover.

MATERIALS AND METHODS

Serum levels of tumour necrosis factor alpha (TNFalpha), interleukin-6 (IL-6), bone-specific alkaline phosphatase (B-ALP), osteocalcin, carboxyterminal crosslinking telopeptide of type I collagen (CTX-I), insulin-like growth factor (IGF)-I and IGF binding protein-3 (IGFBP-3) were measured in 25 patients with CVI and compared to 25 age- and sex-matched healthy controls.

RESULTS

Patients with CVI had significantly higher serum levels of CTX-I and B-ALP, and significantly lower serum levels of IGF-I and IGFBP-3 compared to controls as shown in cross-sectional, and as for B-ALP and CTX-I, also during longitudinal testing. No differences were observed for osteocalcin between the two groups. The elevated B-ALP and decreased IGF-I and IGFBP-3 levels were most pronounced in a subgroup of CVI patients characterised by persistent activation of proinflammatory cytokines in vivo. Raised B-ALP and decreased IGF-I and IGFBP-3 were also significantly correlated with enhanced IL-6 and TNF-alpha levels in these patients.

CONCLUSIONS

The present study suggests that persistent immune activation in vivo, with raised levels of proinflammatory cytokines, may be related to disturbed bone homeostasis in CVI patients, further supporting an interaction between immune related mediators and bone metabolism in humans.

[Marginal primary hyperparathyroidism. Indication for treatment?]

Non familial primary hyperparathyroidism (pHPT) is often diagnosed accidentally by serum calcium screening. Som patients have marginally elevated calcium values, normal renal function, no renal stone disease and no clinical signs of bone disease. Bone densitometry reveals slightly reduced bone mineral content. Long time observation may show no progression. Observation is recommended due to the potentially stationary and symptomfree condition. Recent investigations have however shown that pHPT is associated with cardiac changes and elevated risk of cardiovascular death. Neuropsychiatric changes influencing level of function and quality of life have been demonstrated. There is therefore a substantial need for re-evaluation of the natural course of apparent asymptomatic pHPT and the effect of parathyroid surgery.

[Acromegaly--diagnosis and treatment]

BACKGROUND

Acromegaly is a rare but clinically important disease caused by growth hormone hypersecretion, usually from a pituitary adenoma. The condition is associated with increased morbidity and mortality.

MATERIAL AND METHODS

The prevalence of acromegaly is estimated to be 4-6 cases per million per year. The diagnosis is based on glucose-suppressed plasma growth hormone. When the diagnosis is confirmed, MR imaging of the pituitary gland is performed.

RESULTS

Standard treatment is transsphenoidal microsurgery; however, radicality is often difficult because of extensive tumour growth. Preoperative administration of somatostatin analogues may improve the surgical outcome.

INTERPRETATION

We have initiated a randomized, prospective study to elucidate this adjuvant treatment. Somatostatin analouges are required in the case of postoperative activity. This treatment is without tachyphylaxis and has few side effects. Alternatively, dopamine agonists such as bromocriptine can be used, especially in mixed tumours coproducing prolactin. Newer, more specific dopamine agonists are currently being evaluated. Radiation therapy may be required in large, unresectable tumours, but the effects are slow-acting, and almost all patients develop hypopituitarism. Gamma knife radiosurgery seems promising for stopping tumour growth as well as for decreasing excessive hormone production. However long-time follow-up results are so far lacking.

Serum creatine kinase isoenzyme BB in mammalian osteopetrosis

In mammalian osteopetrosis the different mutations exemplify reduced bone resorption leading to net accumulation of bone. Recently, high blood levels of creatine kinase-BB have been reported in some human forms, suggesting it as a marker of osteopetrosis. In the current study serum creatine kinase-BB was evaluated in relation to known osteoclastic pathophysiology in two human types of autosomal dominant osteopetrosis at baseline and after stimulation with triiodothyronine and in four different rodent mutations. Creatine kinase-BB was increased markedly in Type 2 autosomal dominant osteopetrosis and in the incisors absent rat, both characterized by large numbers of giant osteoclasts, and did not change significantly after stimulation. Although creatine kinase-BB was unchanged in Type 1 autosomal dominant osteopetrosis at baseline and after stimulation, the rodent counterparts characterized by small osteoclasts, microphthalmic and osteopetrotic mice and toothless rats, had significantly decreased levels. Similar differences were observed in both types of autosomal dominant osteopetrosis compared with controls concerning tartrate resistant acid phosphatase. Creatine kinase-BB in mammalian osteopetrosis is related to osteoclastic number and size, where it probably reflects the differentiation and maturation of inactive bone resorbing cells. The isoenzyme does not seem to be a valuable screening marker for osteopetrosis.

Leptin levels in relation to body composition and insulin concentration in patients with endogenous Cushing's syndrome compared to controls matched for body mass index

Cushing's syndrome (CS) is associated with weight gain and visceral obesity. We examined the relationship between regional fat distribution and serum levels of leptin, cortisol and insulin. Twenty-three consecutive patients with recently diagnosed CS (18 with pituitary adenoma, 5 with adrenal tumor), where compared to obese controls, matched for age, sex and Body Mass Index (BMI). Serum insulin, leptin, cortisol, C-peptide and body composition determined by DEXA were measured. Serum leptin levels were significantly increased in patients with CS (36.9+/-3.8 vs 18.9+/-2.4 ng/ml, p<0.001; women: 40.1+/-4.6 vs 21.7+/-2.9 ng/ml, p<0.01; men: 27.9+/-5.7 vs 10.9+/-2.3 ng/ml; p<0.05), the same were fasting insulin levels (178+/-30 vs 81+/-10 pmol/l; p<0.01) and C-peptide (1.51+/-0.12 vs 0.77+/-0.07 nmol/l; p<0.001). In a subgroup of 12 patients, truncal fat mass was significantly elevated when compared to obese controls (19.2 kg vs 14.7 kg, p<0.01, and 42% vs 36% in percentage of truncal body tissue, p<0.05), whereas total fat mass was insignificantly increased. Serum leptin correlated positively to total body fat (%) as in patients with CS (r=0.94, p<0.001) as in controls (r=0.68, p<0.01). The correlation to truncal body fat (%) was also significant in both groups (CS: r=0.84, p<0.001; controls: r=0.63, p<0.01). Multiple regression showed that percent total body fat was the predictor of leptin concentrations among patients with CS (r2=0.88, p<0.001) whereas insulin did not contribute significantly to the variance in leptin concentrations. In controls, both leptin and insulin (r2=0.65, p<0.001) contributed significantly to the variations in leptin levels. Controlled for the differences in total body fat, patients with endogenous CS have significantly increased serum leptin levels, compared to BMI-matched obese controls. This suggests that hyperleptinemia in CS not primarily reflects changes in body composition, but is the result of different hormonal influences on adipose tissue.

[Borderline primary hyperparathyroidism]

The clinical presentation of primary hyperparathyroidism has changed considerably after the application of biochemical autoanalysers. The condition was previously found with characteristic symptoms in bone, kidneys and the gastrointestinal tract; less than 1% of patients were assumed to be asymptomatic. Today, most patients have mild and uncharacteristic symptoms. Primary hyperparathyroidism has been detected with increasing frequency in the western world, but there are large variations within demographically otherwise comparable areas. There are also regional differences regarding the incidence of surgical treatment of the disease. Demographic studies have shown increased morbidity and mortality primarily from cardiovascular and possibly malign diseases related to hypercalcemia. Follow-up studies based on surgical series have shown increased mortality related to preoperative serum calcium level. In view of the altered clinical picture of primary hyperparathyroidism, treatment of moderate and possibly "benign" primary hyperparathyroidism has been actualised. At an international consensus conference in 1990, this patient group was defined by an arbitrary serum calcium limit of 3.0 mmol/l, but this limit has been found to be unacceptably high. Regardless of where the upper limit is set, there are so far well accepted indications for surgery, but only one in two patients fulfil these criteria. A working group of endocrinologists and endocrine surgeons from nine university clinics in Scandinavia have recently initiated a prospective, randomised study evaluating surgical treatment and a systematic follow-up of patients with borderline primary hyperparathyroidism.