Serum Osteoprotegerin Levels In Patients Research Articles

Changes of serum osteoprotegerin level in recurrent urolithiasis

Introduction. In our earlier research on the role of genetic factors in the development of recurrent urolithiasis, a significant relationship was found between the presence of single-nucleotide polymorphism rs3134057 in the osteoprotegerin (OPG) gene and the development of this disease. The above-mentioned single-nucleotide polymorphism is intronic, therefore, it is unable to involve the structure and functions of the OPG but to affect its expression. Thus, the study of serum OPG level may have diagnostic significance in recurrent urolithiasis.Objective. To study the relationship of serum OPG level with the presence of recurrent urolithiasis, as well as the effect of single nucleotide polymorphism rs3134057 on the OPG level.Materials & methods. One hundred and fifteen volunteers were included in the study from January 2021 to January 2022. Of the 115 participants, 45 (main group #1) were diagnosed with recurrent urolithiasis and localisation of the main stone in one of the ureters, 28 participants (main group #2) had previously suffered a single episode of acute renal colic followed by surgical treatment or stone self-discharge and were stone-free at the time of the study. Forty-two control group respondents were free of urolithiasis, including family history of urolithiasis. The serum OPG levels was determined by enzyme immunoassay using the Human OPG ELISA kit ab100617 ("Abcam plc", Cambridge, UK) according to the manufacturer's advice.Results. The analysis revealed that the serum OPG levels were significantly higher in the main group #1 than in the control group (median: 9.02 vs. 3.635, p = 0.012). When analyzing the relationship between the concentration of OPG in serum and the AA + AG genotype versus GG according to rs3134057 of the OPG gene, no statistically significant difference was found (p > 0.05). The same result was obtained when comparing groups with AA vs. AG vs. GG genotypes (p > 0.05).Conclusion. The present study showed that an increased serum OPG level in patients with recurrent urolithiasis may indicate the presence of a relapse of the disease. Further study in large samples will finally confirm the significance of OPG as a marker of relapse, including in genetically determined forms.

Association of Serum Osteoprotegerin Level With Myocardial Injury and Cardiovascular Calcification in Chronic Kidney Disease Patients.

BackgroundChronic kidney disease has emerged as a significant independent risk factor for cardiovascular disease. Cardiovascular calcification is an active process involving a complex interaction of inducers and inhibitors. High sensitivity cardiac troponin T assay detects troponin T with higher sensitivity and precision at an earlier point of time than the conventional assays, and is associated with poor outcomes. Serum osteoprotegerin is classed as an inhibitory factor for cardiovascular calcification. It is involved in the pathological processes of vascular damage and linked to the excess cardiovascular morbidity. The aim of the present study was to evaluate the extent of cardiovascular calcification and serum high sensitivity cardiac troponin T level, and their association with serum osteoprotegerin level in patients with chronic kidney disease stages 3–5.Methods90 chronic kidney disease patients were enrolled in this study, and they were divided into two groups: group (1) included 45 non-dialysis-dependent chronic kidney disease patients (stages 3–5) and group (2) included 45 chronic hemodialysis patients. Each group further subdivided according to the presence of cardiovascular calcification into subgroup A and B. Vascular calcifications were assessed by lateral lumbar, pelvis and hands X-ray radiographs. Valvular calcification was assessed by echocardiography. Serum cardiac troponin T was measured by high sensitivity assay and serum osteoprotegerin was measured by ELISA.ResultsCardiovascular calcification distribution was 22.2% in group (1) and 33.3% in group (2). Serum osteoprotegerin and troponin T in calcification groups (1A and 2A) were significantly higher than non-calcification groups (1B and 2B; P < 0.001). Osteoprotegerin correlated positively with high sensitivity cardiac troponin T (rs = 0.72, P < 0.001). cardiovascular calcification correlated positively with osteoprotegerin, troponin T, and phosphorus. osteoprotegerin and phosphorus were significant independent predictors of cardiovascular calcification at cut-off values ≥4.6 ng/L and ≥6.95 mg/dl, respectively (P < 0.001). Serum phosphorus and creatinine were independent predictors of osteoprotegerin (P < 0.001 and 0.048, respectively).ConclusionOsteoprotegerin is strongly associated with cardiovascular calcification and high sensitivity cardiac troponin T. In addition, there is a positive association between calcification and troponin T. This suggests a role for osteoprotegerin in the pathogenesis and risk stratification of cardiovascular calcification and myocardial injury in chronic kidney disease patients with a potential role as a therapeutic target.

Effect of sequential eradication therapy on serum osteoprotegerin levels in patients with Helicobacter pylori infection and co-existing inflammatory bowel disease.

ObjectiveTo investigate the effect of sequential Helicobacter pylori eradication therapy on serum osteoprotegerin levels in patients with H. pylori infection and co-existing inflammatory bowel disease (IBD).MethodsThree groups of patients were involved in this observational cross-sectional study: IBD (n = 83), H. pylori infection (HP, n = 68), and H. pylori infection with co-existing IBD (HP + IBD, n = 52). These groups were compared with a normal control group (NC, n = 50). Serum osteoprotegerin, serum bone alkaline phosphatase (BALP), and fecal calprotectin (FC) levels were measured.ResultsSerum osteoprotegerin levels were significantly correlated with the simple endoscopic score for Crohn’s disease and Mayo score for ulcerative colitis. The receiver operating characteristic analysis of osteoprotegerin revealed high values for the area under the curve, sensitivity, and specificity. Discriminant analysis illustrated that osteoprotegerin levels significantly differentiated patients with IBD from healthy controls. Osteoprotegerin and FC levels distinguished the IBD and HP + IBD groups from the NC and HP groups.ConclusionsSequential eradication therapy did not affect serum osteoprotegerin levels in patients with H. pylori infection and co-existing IBD. Serum osteoprotegerin elevation might be a marker for IBD development in patients with past or current H. pylori infection.

Prognostic Value of Serum Osteoprotegerin Level in Patients With Hepatocellular Carcinoma Following Surgical Resection.

BackgroundMultiple studies have reported that tissue or serum osteoprotegerin (OPG) level is a prognostic factor for patients with cancer. However, little is known about the role of serum OPG in hepatocellular carcinoma (HCC). In this study, we aimed to investigate whether serum OPG concentration has an effect on HCC patients’ prognosis.MethodsA total of 386 eligible HCC patients undergoing radical hepatectomy were enrolled from Shanghai Ninth People’s Hospital and Zhongshan Hospital between 2010 and 2018. Kaplan-Meier curves, Cox regression model, and the restricted mean survival time (RMST) were used to estimate the association of OPG and HCC patients’ survival outcome. In addition, sensitivity analyses were carried out including subgroup analysis and propensity score matching (PSM).ResultsPatients were separated into two groups according to the cut-off value of OPG calculated by X-tile. Multivariate Cox analysis showed that patients with high OPG level had worse overall survival (OS) (HR: 1.93; 95% CI: 1.40–2.66, p<0.001) and disease-free survival (DFS) (HR: 1.85; 95% CI: 1.39–2.47, p<0.001) before matching. On average, RMST ratio between high and low OPG turned out to be 0.797 (95% CI: 0.716–0.887, p<0.001). In the matched population, we found that OPG level was negatively associated with OS (HR: 1.85; 95% CI: 1.25–2.74, p=0.002) and DFS (HR: 1.71; 95% CI: 1.20–2.44, p=0.003). In addition, a similar trend was further confirmed by subgroup analyses.ConclusionIn a word, HCC patients with high OPG level had poorer survival rates compared with HCC patients with low OPG level. This factor could act as a potential prognostic predictor for HCC patients who underwent radical resection in the future.

The value of serum osteoprotegerin levels in patients with angina like chest pain undergoing diagnostic coronary angiography

Osteoprotegerin (OPG) is a member of the tumor necrosis factor superfamily.Recent evidence supports a relationship between serum OPG level and atherosclerosis. The aim of this study was to evaluate the possible association of OPG with the presence of coronary artery disease (CAD), its severity and prognosis in patients with chest pain and suspected coronary stenosis. In this cross-sectional analytic study, 180 candidates of elective coronary artery angiography were recruited. Serum level of OPG was measured by ELISA method in all patients and its relation with presence and severity of CAD based on a coronary atherosclerosis score (CAS) was assessed. Patients were followed for a mean period of about 24 ± 3.2 months and the relationship between OPG levels and future cardiac events were evaluated. The mean serum level of OPG was 1637 ± 226 pg/mL in those with CAD and 1295 ± 185 pg/mL (nonparametric p = 0.001) in those without it. There was a significant direct correlation between the level of serum OPG and CAS (rho = 0.225, p = 0.002). The optimalcut-off point for predicting a significant coronary artery obstruction was a serum level of≥ 1412 pg/mL with a sensitivity and specificity of 60% and 57.8%, respectively. Major adversecardiac events (MACE) including cardiovascular death, admission with acute coronary syndrome,or heart failure, was significantly higher in those with higher OPG levels (22 [34.3%]vs. 15 [16%], p = 0.012). There was a direct and significant correlation between the serum level of OPG and CAS. MACE occurred more commonly in those with higher baseline OPG levels.

Serum Osteoprotegerin and Sex Steroid Levels in Patients With Prostate Cancer

The relationship between sex steroids and osteoprotegerin (OPG) in patients with prostate cancer is not well established. Our aim was to evaluate serum OPG levels in patients with prostate cancer and its relationship with sex steroids, bone mineral density, bone turnover markers, and fractures. We performed a cross-sectional study including 91 patients with prostate cancer. We determined: bone mineral density by dual-energy x-ray absorptiometry, bone turnover markers, serum levels of sex steroids and osteoprotegerin, and prevalent radiographic vertebral fractures. Serum OPG levels were higher in patients with vertebral fractures (8.02 ± 2.0 vs 4.91 ± 0.28 pmol/L; P < .05). OPG level and the duration of hormonal therapy were related (r = 0.299, P = .004), but this association did not persist after adjustment for age. In patients without androgen deprivation therapy, serum OPG levels were correlated with the levels of total testosterone (r = 0.508, P = .001) and bioavailable testosterone (r = 0.311, P = .037). In patients receiving androgen deprivation therapy, serum OPG levels were correlated with levels of total estradiol (r = 0.199, P = .18), bioavailable estradiol (r = 0.37, P = .009), and free estradiol (r = 0.349, P = .016). In conclusion, in patients with prostate cancer treated with androgen deprivation therapy, serum OPG levels were correlated with the levels of total estradiol, bioavailable estradiol, and free estradiol. Our hypothesis is that in patients with androgen deprivation therapy, the higher relative estrogen levels could stimulate OPG production in response to the higher resorption state. Future prospective studies are needed to clarify the role of OPG in androgen deprivation therapy-mediated bone loss.

Association of serum osteoprotegerin levels with bone mineral density and bone turnover markers in patients with hyperthyroidism before and after methimazole treatment

Serum bone alkaline phosphatase (BAP) , osteocalcin (OC) , C-telopeptides of type-1 collagen (CTx) , osteoprotegerin (OPG) levels, and bone mineral density (BMD) were evaluated in 62 hyperthyroid patients and 60 healthy subjects matched for sex and age. In hyperthyroid patients, the biochemical evaluations and bone density were performed before and after 6 months of methimazole ( MMI) treatment. Results showed that the BMD in lumbar spine L2 - L4, neck of femur, Ward's triangle and greater trochanter of patients before treatment were all significantly lower than those in healthy controls, and improved markedly after MMI treatment. The serum bone turnover parameters BAP, OC and CTx in patients before treatment were all significantly higher than those in control group, and were decreased markedly after treatment. The serum OPG level in patients with hyperthyroidism was significantly higher than that in healthy controls, and decreased markedly after treatment. The serum OPG levels were significantly correlated with bone turnover parameters ( BAP, OC, CTx) and BMD, which indicates that serum OPG level can reflect the abnormality of bone metabolism in patients with hyperthyroidism. Key words: Hyperthyroidism; Osteoprotegerin

Non-traditional risk factors predict coronary calcification in chronic kidney disease in a population-based cohort

The increased burden of cardiovascular disease in chronic kidney disease cannot be explained by traditional risk factors alone. Here, we evaluated the impact of non-traditional factors on the association of chronic kidney disease with coronary artery calcification using logistic regression among 2672 Dallas Heart Study patients of whom 220 had chronic kidney disease. The prevalence of coronary calcification significantly increased across all chronic kidney disease stages and this remained independently associated with coronary calcification after adjusting for traditional factors. The calcium x phosphorus product, homocysteine, and osteoprotegerin each diminished the magnitude of association between kidney disease and coronary calcification. After adjustment for these, the association between kidney disease and coronary calcification was no longer significant with the effects most prominent in the stages 3-5 subgroup. Our study has identified three non-traditional independent predictors of coronary calcification that diminished the association between chronic kidney disease and coronary calcification. These factors may represent novel mechanistic links warranting further investigation.

The fallacy of the calcium-phosphorus product

Scattered through the practice of medicine are dogmas with little or no scientific basis. One of these is the product of the serum calcium and phosphorus concentrations, the so-called calcium-phosphorus product or Ca x P. The assumption that ectopic calcification will occur when the product of the serum calcium and phosphorus concentrations exceeds a particular threshold has become standard practice in nephrology even though there is little scientific basis. Experimental support is lacking, the chemistry underlying the use of the product is oversimplified and the concept that ectopic calcification is simply the result of supersaturation is biologically flawed. The evidence that the Ca x P is an independent risk factor for mortality and morbidity is also questionable. Although ectopic calcification can occur in many sites, this review will focus on vascular calcification, as it is the most common site and the site most likely to affect patient outcomes.

Serum osteoprotegerin levels in patients with acute atherothrombotic stroke and lacunar infarct

Background Arterial calcification is associated with increased risk of cardiovascular events. Osteoprotegerin (OPG) is a cytokine involved in the bone metabolism and vascular calcification. Recent data support a relationship between high serum levels of OPG and increased risk for cardiovascular disease in human. The aim of this study was to evaluate the OPG serum levels in acute ischemic stroke. Our study was further designed to detect differences in serum OPG levels between subtypes of ischemic stroke. Materials and methods The study consisted of 51 patients with acute ischemic stroke and 28 control subjects. Stroke subtypes were defined by the TOAST classifications. Serum OPG levels were measured with the ELISA method. Results OPG serum levels were significantly higher in patients with ischemic stroke than in control subjects ( p < 0.001). OPG serum levels were significantly higher in large-vessel disease (LVD) subtype compared with small-vessel disease (SVD) subtype and controls ( p < 0.001, p < 0.001). There was no significant difference in OPG serum levels between SVD group and control subjects. Serum OPG levels were correlated with age ( r = 0.407, p = 0.005) and fasting glucose levels ( r = 0.542, p = 0.001) in ischemic stroke group. Logistic regression analysis showed that plasma OPG levels (OR 2.1, 95% CI, 1.16 to 3.4, p = 0.01) associated with presence of stroke independently of the other risk factors. Conclusions High serum OPG levels were associated with the LVD stroke subtype, suggesting that OPG levels may play role in pathogenesis of atherothrombotic stroke. The precise mechanism for the role of OPG in atherosclerosis needs to be investigated further.

Assessment of a Serum Assay for Quantification of Abdominal Aortic Calcification

Intimal vascular calcification is an important marker of atherosclerosis, and its severity is an independent risk factor for cardiovascular events. Measurement of coronary or aortic calcification requires CT-based imaging and elaborate data analysis to ensure accuracy. A blood assay which could quantify the severity of vascular calcification would be less expensive, avoid exposure to radiation, and be more accessible than present imaging based methods. Osteoprotegerin (OPG) and osteopontin (OPN) are present in human serum and have been implicated in vascular calcification. In this prospective study we assessed the value of a number of serum assays for OPG and OPN in determining abdominal aortic calcification. Firstly, we investigated the assay characteristics and reproducibility of 5 ELISAs using a subset of patients. Based on the findings of these assessments, we selected 3 assays for full evaluation in the entire cohort.

Prognostic significance of the level of serum osteoprotegerin in patients with bladder cancer

4581 Background: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) plays an important role in cytotoxic T lymphocyte-mediated and natural killer cell-mediated apoptosis against cancer cells. Since Osteoprotegerin (OPG) is a soluble decoy receptor for TRAIL, circulating OPG has been implicated in protection from TRAIL-mediated apoptosis. This possibility was examined in patients with bladder cancer. Methods: Serum OPG levels of 185 patients with bladder cancer were determined by using an enzyme-linked immunosorbent assay. Anti-autologous tumor cytotoxic activity of peripheral blood lymphocytes was assessed by the 12-h Cr release assay. Results: The mean serum OPG level in patients with bladder cancer was approximately 3-fold higher than that in normal donors. The serum OPG level in patients with muscle-invasive bladder cancer was higher than that in superficial bladder cancer. Furthermore, serum level of OPG in patients with metastatic bladder cancer was higher than that in muscle-invasive bladder cancer. Serum OPG level in Grade 2 bladder cancer was higher than that in Grade 1 cancer. Moreover, serum OPG level in Grade 3 bladder cancer was higher than that in Grade 2 cancer. Patients with superficial bladder cancer with low serum OPG level had a longer postoperative tumor-free rate than those with high level in the 5-year follow-up. In addition, patients with muscle-invasive bladder cancer with low serum OPG level had a higher disease-specific survival rate when compared with patients with high level in the 5-year follow-up. There was an inverse correlation between serum OPG level and anti-autologous tumor cytotoxic activity. Conclusions: The present study is the first to demonstrate that the serum OPG level correlates with the stage/grade of bladder cancer, and that elevated level serum OPG predicted early recurrence in patient with bladder cancer. These findings suggest that serum OPG level may be used as a prognostic parameter in patients with bladder cancer, and that OPG may be a molecular therapeutic target in bladder cancer. No significant financial relationships to disclose.

Osteoprotegerin and Bone Mass in Squamous Cell Head and Neck Cancer Patients

Osteoprotegerin (OPG) is considered one of the main regulators of bone remodeling. Various patterns of serum OPG levels have been described in different types of tumors. We undertook this study to determine serum OPG levels in patients with squamous cell head and neck cancer (SCHNC), analyzing their relationship with other metabolic bone parameters and bone mineral density (BMD), as well as the possible influence of chemotherapy. Forty male patients with localized SCHNC were studied, and their results were compared with those of 40 healthy male controls. The type of treatment followed by each patient was noted. Age, weight, height, and lifestyle habits were recorded; and OPG, Ca(2+), intact parathyroid hormone (iPTH), 25-Hydroxyvitamin D (25OHD) and 1,25-Dihydroxyvitamin D (1,25(OH)(2)D), bone alkaline phosphatase, osteocalcin, and serum C-terminal cross-links telopeptide of type I collagen (ICTP) were determined. Dual-energy X-ray absorptiometry BMD at the lumbar spine, femoral neck, and hip was also measured. Serum OPG was higher in patients than in controls (91.7 +/- 25.8 vs. 77.2 +/- 26.3, P = 0.02). ICTP (a bone resorption marker) was 37% higher in patients (P = 0.007). Bone mass was lower in patients at the lumbar spine, femoral neck, and total hip. Lumbar spine Z-score showed a significant progressive decrease in controls, stage I-III patients, and stage IV patients. Logistic regression analysis showed a significant association between the disease and serum OPG levels, the odds ratio per standard deviation increase of this being 1.9 (95% confidence interval 1.1-3.8, P = 0.04) after adjusting for bone mass and ICTP serum levels, as well as for alcohol and smoking history. Adjustment for alcohol intake and tobacco use did not cancel out BMD differences between patients and controls. Patients with SCHNC show increased OPG serum levels, increased bone resorption, and decreased bone mass. The OPG rise appears to be unrelated to the BMD decrease, and the BMD decrease seems to be, at least in part, independent of smoking and drinking habits. No differences in either OPG or BMD were seen between patients with and without chemotherapy. Further studies are needed to clarify the mechanisms responsible for OPG and BMD changes in SCHNC.

991: Prognostic Significance of Serum Osteoprotegerin Level in Patients with Bladder Cancer

991: Prognostic Significance of Serum Osteoprotegerin Level in Patients with Bladder Cancer

Relationship of serum osteoprotegerin levels with coronary artery disease severity, left ventricular hypertrophy and C-reactive protein

OPG (osteoprotegerin) is an inhibitor of osteoclastogenesis and recent work suggests it has a role in atherosclerosis. Therefore we measured serum OPG levels in patients with coronary artery disease, compared the serum OPG levels among the different groups according to the number of stenotic vessels and determined whether there was any correlation with aortic calcification, LV (left ventricular) mass index and serum CRP (C-reactive protein) levels. Subjects (n=100; mean age, 57 years) who underwent coronary angiograms were enrolled. Blood pressure, body mass index, fasting blood glucose, lipid profiles and CRP levels were measured and the LV mass indices were calculated using ECGs. Serum OPG levels were measured by ELISA. The presence of calcification in the aortic notch was checked by a chest X-ray. The subjects were divided into four groups according to the number of stenotic vessels. The mean serum OPG levels increased significantly as the number of stenotic vessels increased, and the mean serum OPG levels were higher in the group with three-vessel disease compared with the groups with no- or one-vessel disease. The mean serum CRP level was significantly higher in the group with three-vessel disease compared with the groups with no-, one- and two-vessel disease. Age and LV mass index showed significant positive correlations with serum OPG levels, although significance was lost after an adjustment for age. Serum CRP levels were positively correlated with serum OPG levels even after an adjustment for age. There were no differences in serum OPG levels according to the presence of fasting hyperglycaemia or aortic calcification. In conclusion, serum OPG level was related to the severity of stenotic coronary arteries and serum CRP levels. LV mass indices showed no significant correlation with OPG levels. The precise mechanism for the role of OPG in atherosclerosis needs to be investigated further.

Decreased serum osteoprotegerin levels in patients with cardiac syndrome X

Receptor activator of nuclear factor KB (RANK) and osteoprotegerin (OPG) represent the ligand and decoy receptor, respectively, of a pleiotropic cytokine system that regulates bone metabolism and vascular biology. Several studies supported systemic microvascular abnormalities in patients with cardiac syndrome X (CSX). This study investigates serum OPG levels in healthy obese subjects and healthy lean controls affected by cardiac syndrome X. We compared the OPG levels in 8 patients with cardiac syndrome X [2 males, 6 females; age: 46+/-6 yr; body mass index (BMI): 30+/-5 kg/m2] with 24 obese subjects (8 males, 16 females; age: 38+/-5 yr; BMI: 35+/-5 kg/m2) and 15 healthy lean controls (6 males, 9 females; age: 36+/-5 yr; BMI: 23+/-2 kg/m2; BMI<25kg/m2). Serum OPG levels in patients with cardiac syndrome X were lower than those in obese subjects and lean controls (11.45+/-8.36 pg/ml, 14.78+/-8.22 pg/ml, 19.24+/-6.96 pg/ml, respectively, cardiac syndrome X vs lean controls, p=0.039). Serum OPG levels are lower in patients with CSX. Further studies on the mechanisms of OPG in microangiopathy may help to evaluate the OPG system role as a marker for disease activity, prognosis and response to therapy in cardiovascular diseases.

High serum osteoprotegerin levels in patients with hyperthyroidism: effect of medical treatment

This study was aimed at evaluating serum osteoprotegerin (OPG) concentrations in a cohort of patients with hyperthyroidism before and after methimazole (MMI) treatment. One hundred fourteen hyperthyroid patients [93 with Graves disease (GD) and 21 with toxic nodular goitre (TNG)] and 68 matched for sex and age healthy subjects were evaluated for serum free-thyroxine (FT4), free-triiodiothyronine (FT3), thyrotropin (TSH), TSH receptor antibodies (TRAb), bone alkaline phosphatase (BALP), C-telopeptides of type-1 collagen (CrossLaps), OPG levels, and bone mineral density (BMD). In hyperthyroid patients, the biochemical evaluations were performed before and after 6 and 12 months of MMI treatment, whereas BMD was measured at baseline and after 12 months of treatment. Hyperthyroidism was more severe in GD than TNG patients. Serum OPG levels were found to be significantly higher in hyperthyroid patients than in the healthy subjects (4.3 pmol/l, range: 1.6–12.0, vs. 2.2 pmol/l, range: 1.4–6.0; P < 0.001), the values being higher in GD patients than TNG. A significant correlation between serum OPG levels and age was found in the healthy subjects ( r: 0.48; P < 0.001) but not in hyperthyroid patients ( r: −0.03; P = 0.8). In the healthy subjects, serum OPG levels were also positively correlated with both serum FT4 ( r: 0.23; P = 0.03) and FT3 ( r: 0.24; P = 0.04) levels. In hyperthyroid patients, however, serum OPG was still correlated with FT3 levels ( r: 0.38; P < 0.001), whereas the correlation with serum FT4 was lost ( r: 0.19; P = 0.06). In hyperthyroid patients, but not in the healthy subjects, serum OPG levels were correlated positively with CrossLaps ( r: 0.20; P = 0.03) and negatively with BALP ( r: −0.24; P = 0.01) and BMD ( r: −0.33; P = 0.01). After 6 months of MMI treatment, serum OPG concentrations decreased significantly in TNG patients (from 3.5 pmol/l, range: 1.6–8.0, to 2.3 pmol/l, range: 1.0–4.3; P < 0.001), whereas a not significant change in OPG levels occurred in GD patients (from 4.8 pmol/l, range: 1.8–12.0, to 4.2 pmol/l, range: 1.0–14.0; P = 0.7). At Month 12 of treatment, serum OPG concentrations were significantly lower than those measured at baseline in both TNG (2.5 pmol/l, range: 1.0–3.1, vs. 3.5 pmol/l, range: 1.6–8.0; P < 0.001) and GD (2.1 pmol/l, range: 1.0–8.6, vs. 4.8 pmol/l, range: 1.8–12.0; P < 0.001). At this time, no significant differences in serum OPG, CrossLaps, and BALP values were found between patients and control subjects. At the end of follow-up, BMD was higher than those measured at baseline but still significantly lower than those measured in the control subjects. This study shows that hyperthyroid patients have serum OPG concentrations significantly higher in comparison with euthyroid subjects, in relation to thyroid hormone excess and high bone turnover. Medical treatment of hyperthyroidism normalizes serum OPG levels in temporal relationship with the normalization of bone metabolism markers, even in presence of persistent abnormal bone structure as determined by ultrasonography.

The progression of vascular calcification and serum osteoprotegerin levels in patients on long-term hemodialysis

Background:The aortic calcification index (ACI), estimated on abdominal computed tomographic scans, has been associated with the extent of arteriosclerosis in hemodialysis patients. However, the contribution of biochemical markers to the progression of vascular calcification in patients undergoing hemodialysis is not fully understood. Methods:We examined the relationship between coronary risk factors; metabolic factors, including serum osteoprotegerin (OPG) concentration; and progression of vascular calcification in 26 dialysis patients. Results:Mean patient age was 52.6 ± 8.7 (SD) years, and mean duration of dialysis therapy was 7.7 ± 5.8 years. ACI was measured twice in each patient, and the mean interscan period was 4.9 ± 0.3 years. Mean ACI changed from 22.2 ± 24.2 to 33.9 ± 28.8 overall, and mean change in ACI (ΔACI) was 12.0 ± 9.9. Patients were divided into 2 groups: slow progressors, with ΔACI of 4.1 ± 3.2 (n = 13), and rapid progressors, with ΔACI of 19.8 ± 7.9 (n = 13). Serum fasting glucose and CRP levels of rapid progressors were high, and their serum albumin and intact parathyroid hormone levels were low. Multiple regression analyses showed that serum OPG levels were independently associated with vascular calcification in the hemodialysis patients studied. Conclusion:Rapid progression of vascular calcification was associated with dose of calcium carbonate prescribed and serum OPG concentration. The clinical significance of these observations remains to be determined.