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.

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.

Uteroplacental arterio-venous difference in soluble VEGFR-1 (sFlt-1), but not in soluble endoglin concentrations in preeclampsia.

The aim was to determine plasma levels of sFlt-1 and sEng on the arterial and venous side of the uteroplacental circulation in preeclamptic patients and healthy controls. Preeclamptic patients had higher arterial concentrations than controls of sFlt-1 (17,450 vs. 5055 pg/ml, p = 0.003) and sEng (68.7 vs. 28.7 ng/ml, p = 0.003). In the preclampsia group sFlt-1 was higher in the uterine vein than in the radial artery (22,450 vs. 17,450 pg/ml, p = 0.005). We found no gradient for sEng. Our results support the hypothesis that excess sFlt-1 at least partly originates in placenta, while excess sEng appears to have a different origin.

Increased interleukin-1ß levels are associated with left ventricular hypertrophy and remodelling following acute ST segment elevation myocardial infarction treated by primary percutaneous coronary intervention.

OBJECTIVES: To assess the relationship between interleukin (IL)-1-related molecules, infarct size and left ventricular (LV) remodelling following acute myocardial infarction (MI). METHODS: Forty-two patients with first-time diagnosis of ST segment elevation MI (STEMI), with a single occluded vessel successfully revascularized by primary percutaneous coronary intervention (PCI), were recruited to this observational study conducted at a university teaching hospital and followed for 1 year. MAIN OUTCOME MEASURES: Plasma levels of IL-1ß, IL-1 receptor antagonist (IL-1Ra), IL-18 and caspase-1 were analysed before and 2 days, 1 week and 2 months after PCI. Serial cardiac magnetic resonance imaging (CMR) was used for the assessment of infarct size and LV remodelling. CMR findings at 1 year was the primary outcome variable. RESULTS: Univariate analysis showed that IL-1-related mediators were strongly (IL-1 ß), moderately (caspase-1) and weakly (IL-1Ra) associated with impaired myocardial function and noninfarct mass, but not infarct size, 1 year after reperfused STEMI. In multivariate analyses, troponin T predicted LV ejection fraction (LVEF), infarct size and LV end-diastolic (LVEDVi) and end-systolic volume index (LVESVi). However, significant additional variance was explained by IL-1ß, IL-18 and caspase-1. IL-1ß levels at 2 months, IL-18 at 2 days and pre-PCI caspase-1 were predictors of LVEF. Caspase-1 and in particular IL-1ß at 2 days were the only predictors of noninfarct mass. IL-1ß and IL-18 at 2 days were predictors of LVEDVi, whilst pre-PCI levels of IL-1ß contributed to prediction of LVESVi. By contrast, pro-B-type natriuretic peptide, C-reactive protein, IL-6 and transforming growth factor-ß1 (TGF-ß1) had no or only a weak (TGF-ß1) association with these CMR parameters in multivariate analyses. CONCLUSIONS: IL-1ß levels after STEMI were strongly associated with impaired myocardial function and noninfarct LV mass after 1 year, suggesting a potential role for IL-1ß as a predictor of maladaptive myocardial remodelling following reperfused MI.

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.

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.

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.

The interleukins IL-6 and IL-1Ra: a mediating role in the associations between BMI and birth weight?

The biological mechanisms in the association between maternal body mass index (BMI) and birth weight are not well understood, but are likely to involve maternal plasma glucose levels and nutrient transport across the placenta, both important modulators of fetal growth. Adipose tissue contributes to circulating levels of interleukins that may affect glucose metabolism and possibly also placental transport of nutrients. We investigated possible mediating roles of Interleukin 6 (IL-6) and Interleukin 1 Receptor antagonist (IL-1Ra) in 208 pregnant women. Known and hypothesized dependencies between BMI in early pregnancy and fasting glucose, IL-1Ra and IL-6 at gestational weeks 30-32, and birth weight were specified in a path diagram. Standardized regression coefficients, expressing direct, indirect and total effects, were estimated by Bayesian path analysis. Mean (s.d.) BMI was 24.9 kg/m2 (4.2) and mean (s.d.) birth weight 3748 g (454). The total effect of BMI on birth weight was 0.24 (95% credibility interval (CrI) [0.12, 0.36]). The direct effect of IL-1Ra on birth weight was not statistically significant, but significant effects of BMI on IL-1Ra (0.61, 95% CrI [0.51, 0.72]), of IL-1Ra on fasting glucose (0.17, 95% CrI [0.01, 0.34]) and of fasting glucose on birth weight (0.14, 95% CrI [0.01, 0.27]) implied an indirect pathway from BMI via IL-1Ra on birth weight. Approximately 20% of the effect of BMI on birth weight was mediated through IL-1Ra. For IL-6, no such effects were found. Our results indicate that IL-1Ra may be a mediator in the association between BMI and birth weight.

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 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.

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.

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.

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.

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.

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.

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.

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.