The effect of 30 min of supine rest on plasma renin concentrations in paediatric patients.

AIM: The aim of this study is to interpret plasma renin concentrations (PRCs) correctly in a clinical setting, it is essential to understand to what extent physical activity influences the concentration. Reference values for different postural positions exist for adults, but data for children are sparse. In this study, the effect of 30 min of rest on plasma renin concentrations in paediatric patients was examined. METHODS: In total, 41 paediatric patients, undergoing either arginine or clonidine provocation tests for growth hormone deficiency, were included. For each stimulation test, two blood samples were drawn. One at time 0 min and one after 30 min of rest. In total, renin concentrations were determined in 86 serum samples. RESULTS: Renin concentrations decreased from 0 to 30 min with a median value of -20.5% (inter-quartile range: -33.0% to -12.8%). This decrease was not dependent on sex, age, medication or comorbidity, and the variance of renin did not differ between 0 and 30 min. CONCLUSION: Renin concentrations in children differ according to postural position, which is comparable to adults. Thus, the clinical interpretation of renin results needs to consider the preanalytical conditions applied in the local reference population.

Sarcopenia and self-reported markers of physical frailty in patients with osteoporosis.

Bone and muscle impairment, named osteoporosis and sarcopenia, may co-occur with age, and patients with both disorders might exhibit physical frailty. One-hundred sixty-three patients were included. 14.2% had both disorders and presented more frequent with previous fall, reduced daily activity level, walk/balance challenges, and need of walking aid, indicating overall frailty. PURPOSE: In older adults, sarcopenia (muscle impairment) and physical frailty may accompany osteoporosis (bone brittleness), yet osteoporosis is typically assessed without evaluating these conditions, even though coexistence may contribute to exacerbated negative health outcomes. We aimed at evaluating the prevalence of sarcopenia and impaired muscle domains in osteoporotic patients and explore the risk of osteosarcopenia from markers of physical frailty. METHODS: In Copenhagen, Denmark, osteoporotic patients aged 65 + were assessed cross-sectionally in 2018-2019. Evaluations included muscle mass, strength, and function; bone mineral density; and self-reported physical activity, fall, balance challenges, dizziness, and the need of walking aid. Low bone mass, low-energy fracture, or treatment with anti-osteoporotic medication defined patient with osteoporosis, and sarcopenia was defined by low muscle strength and mass. Osteosarcopenia was defined from the coexistence of both conditions. RESULTS: One-hundred sixty-three patients with osteoporosis were included. Of those, 23 (14.2%) exhibited sarcopenia, hence osteosarcopenia. Hand-grip-strength, 30-s-chair-stand-test, relative-appendicular-lean-muscle-mass, and gait-speed were below cut-off levels in 21.0%, 30.9%, 28.8%, and 23.6% of the patients, respectively. Previous fall, activity level, walk and balance challenges, and need of walking aid were statistically (or borderline) significantly more often affected in the osteosarcopenic group compared with the solely osteoporotic. Logistic regression analysis, however, revealed that only the need for walking aid significantly increased the risk of an osteosarcopenia diagnosis (odds ratio 5.54, 95% CI (1.95-15.76), p < 0.01). CONCLUSIONS: Sarcopenia and impaired muscle domains were frequent in osteoporotic patients, as were markers of physical frailty, indicating the need of thorough examination of osteoporotic patients.

Nutritional status as independent prognostic factor of outcome and mortality until five years after hip fracture: a comprehensive prospective study.

We determined the prognostic value of nutritional status for outcome after hip fracture. Nutritional status was a strong independent prognostic factor for clinical outcome and 5-year mortality. Physical function showed incomplete recovery. Elderly care should focus on prevention already before hip fracture. PURPOSE: To determine the prognostic value of nutritional status in hip fracture patients for multiple clinical and functional outcomes over 6 months, and for new fractures and survival over 5 years post-fracture. METHODS: We included 152 well-characterized subjects (age 55+ years) with a hip fracture from a previously published randomized controlled trial. Nutritional status was appraised using the Mini Nutritional Assessment (MNA). Multivariable linear, logistic and Cox regression models were fitted, adjusted for age, sex, ASA score, group and additional prognostic covariates identified in backward regression models. RESULTS: At baseline, impaired nutritional status was significantly associated with physical disability, depression, impaired cognition and lower quality of life. Prospective analyses showed that impaired baseline nutritional status was an independent prognostic factor for postoperative complications (OR 2.00, 95%CI 1.01-3.98, p = 0.047), discharge location from hospital (home vs. rehabilitation clinic, OR 0.41, 95%CI 0.18-0.98, p = 0.044), hospital readmission (OR 4.59, 95%CI 1.70-12.4, p = 0.003) and total length of hospital stay (HR of being discharged: 0.63, 96%CI 0.44-0.89, p = 0.008), as well as for 5-year mortality (HR 3.94, 95%CI 1.53-10.2, p = 0.005), but not for risk of new fractures (5y-HR 0.87, 95%CI 0.34-2.24, p = 0.769). Curves of physical disability over time showed that the three nutritional status categories followed almost parallel trajectories from baseline until 6 months after hip fracture, without complete recovery and even with further deterioration in malnourished subjects from 3 to 6 months post-fracture. CONCLUSION: As baselline nutritional status is a strong independent prognostic factor for clinical outcome after hip fracture, affecting even five-year survival, elderly health care should focus on prevention and identification of at-risk individuals already before hip fracture.

Effect of 12-months testosterone replacement therapy on bone mineral density and markers of bone turnover in testicular cancer survivors - results from a randomized double-blind trial.

BACKGROUND: Testicular cancer survivors (TCS) are at risk of Leydig cell insufficiency, which is a condition characterized by elevated luteinising hormone (LH) in combination with low levels of testosterone. It has been suggested that this condition is associated with impaired metabolic profile and low bone mineral density (BMD). The primary aim of the randomized double-blind trial NCT02991209 was to evaluate metabolic profile after 12-months testosterone replacement therapy (TRT) in TCS with mild Leydig cell insufficiency. Here we present the secondary outcomes of changes in BMD and markers of bone turnover. METHODOLOGY: In total, 69 TCS with mild Leydig cell insufficiency were randomized 1:1 to 12 months TRT (n = 35) (Tostran, gel, 2%, applied transdermally, with a maximum daily dose of 40 mg) or placebo (n = 34). BMD and markers of bone turnover were evaluated at baseline, after 6- and 12-months TRT, and 3-months post-treatment. Linear mixed effects models were used to analyse changes in BMD, N-terminal propeptide of type 1 procollagen (P1NP) and C-terminal telopeptide of type I collagen (CTX). RESULTS: After 12 months treatment, TRT was not associated with a statistically significant difference in BMD compared to placebo; total body BMD: 0.01 g/cm2 (95% confidence interval (CI): -0.01 - 0.02), BMD of the lumbar spine: 0.01 g/cm2, (95% CI: -0.01-0.03), BMD of the left femoral neck: 0.00, (95% CI: -0.01-0.02). TRT was associated with a small but statistically significant increase in P1NP: 11.65 µg/L (95% CI: 3.96, 19.35), while there was no difference in CTX. CONCLUSION: 12 months of TRT did not change BMD, while there was as small and clinically irrelevant increase in P1NP compared to placebo in TCS with mild Leydig cell insufficiency. The findings need validation in a larger cohort.

Testicular torsion and subsequent testicular function in young men from the general population.

STUDY QUESTION: Is prior testicular torsion associated with testicular function (semen quality and reproductive hormones) in young men from the general population? SUMMARY ANSWER: In young men from the general population, no differences in semen parameters were observed in those who had experienced testicular torsion compared to controls and observations of higher FSH and lower inhibin B were subtle. WHAT IS KNOWN ALREADY: Testicular function may be impaired after testicular torsion, but knowledge is sparse and based on studies with small sample sizes and no control group or a less than ideal control group. STUDY DESIGN, SIZE, DURATION: A cross-sectional population-based study was carried out including 7876 young Danish men with unknown fertility potential, examined from 1996 to 2020. PARTICIPANTS/MATERIALS, SETTING, METHODS: All men (median age 19.0 years) had a physical examination, provided a blood and semen sample, and filled in a questionnaire including information about prior testicular torsion, birth, lifestyle and current and previous diseases. Markers of testicular function, including testis volume, semen parameters and reproductive hormones, were compared between men operated for testicular torsion and controls, using multiple linear regression analyses. MAIN RESULTS AND THE ROLE OF CHANCE: The average participation rate was 24% for the entire study period. In total, 57 men (0.72%) were previously operated for testicular torsion (median age at surgery 13.4 years) of which five had only one remaining testicle. Men with prior testicular torsion were more often born preterm (25% versus 9.5% among controls), and they had significantly higher FSH and lower inhibin B levels, and a lower inhibin B/FSH ratio than controls in crude and adjusted models. The association was mainly driven by the subgroup of men who had undergone unilateral orchiectomy. No differences in semen parameters were observed. LIMITATIONS, REASONS FOR CAUTION: A limitation is the retrospective self-reported information on testicular torsion. Also, results should be interpreted with caution owing to the high uncertainty of the observed differences. WIDER IMPLICATIONS OF THE FINDINGS: Overall, the results of our study are reassuring for men who have experienced testicular torsion, especially when treated with orchiopexy, for whom reproductive hormone alterations were subtle and without obvious clinical relevance. Our study found no differences in semen parameters, but follow-up studies are needed to assess any long-term consequences for fertility. STUDY FUNDING/COMPETING INTEREST(S): Financial support was received from the Danish Ministry of Health; the Danish Environmental Protection Agency; the Research fund of Rigshospitalet, Copenhagen University Hospital; the European Union (Contract numbers BMH4-CT96-0314, QLK4-CT-1999-01422, QLK4-CT-2002-00603, FP7/2007-2013, DEER Grant agreement no. 212844); A.P. Møller and wife Chastine Mckinney Møllers Foundation; Svend Andersens Foundation; the Research Fund of the Capital Region of Denmark; and ReproUnion (EU/Interreg). The authors have nothing to declare. TRIAL REGISTRATION NUMBER: N/A.

Do bone turnover markers reflect changes in bone microarchitecture during treatment of patients with thyroid dysfunction?

PURPOSE: This study aimed to compare changes in the bone turnover markers (BTMs)-C-terminal telopeptide of type I collagen (CTX-I) and procollagen I N-terminal peptide (PINP)-with changes in the bone microarchitecture, assessed by high-resolution peripheral quantitative computed tomography (HR-pQCT), during treatment of patients with thyroid dysfunction. METHODS: In women with newly diagnosed hypo- or hyperthyroidism, HR-pQCT variables, obtained from the tibia and the radius, were compared with BTMs. Data were collected at diagnosis and after at least 12 months of euthyroidism. RESULTS: 73 women completed the study (hypothyroidism, n = 27; hyperthyroidism, n = 46). Among hyperthyroid patients, correlations were found between changes in BTMs and HR-pQCT variables, primarily for cortical variables in the tibia, i.e. cortical thickness (CTX-I, p < 0.001; PINP, p < 0.001), and volumetric bone mass density (vBMD) (CTX-I, p < 0.001; PINP, p < 0.001). Moreover, correlations between BTMs and estimated bone strength were found. In the hypothyroid subgroup, no significant findings existed after adjustment. Following treatment, less decrease in tibial vBMD was seen among patients with increasing CTX-I compared to those with a decreasing CTX-I level (p = 0.009). Opposite findings applied to PINP, as patients with decreasing PINP showed an increase in tibial vBMD, in contrast to a decline in this parameter among patients with increasing PINP (p < 0.001). CONCLUSION: Changes in CTX-I and PINP correlated with HR-pQCT variables during the treatment of women with thyroid dysfunction. To some extent, these BTMs reflected the restoration of bone microarchitecture. CTX-I seems to be the most sensitive BTM in treatment-naïve thyroid diseases, while PINP is more useful for monitoring during treatment. TRIAL REGISTRATION NUMBER: NCT02005250. Date: December 9, 2013.

Circadian rhythm of markers of bone turnover in patients with chronic kidney disease.

Patients with chronic kidney disease (CKD) have a high risk of bone fractures. A circadian rhythmicity in turnover and mineralization of bone appears to be of importance for bone health. In CKD disturbances in the circadian rhythm of various functions has been demonstrated and indeed the circadian rhythm in the mineral metabolism is disturbed. The aim of the present study was to compare the circadian rhythm of bone turnover markers in ten patients with CKD to ten healthy controls. Bone turnover markers (C-terminal telopeptide of type I collagen, tartrate-resistant acid phosphatase 5b, N-terminal propeptide of type I procollagen, bone alkaline phosphatase and osteocalcin) were measured every third hour for 24 h. All bone turnover markers displayed a significant circadian rhythm in both groups and there were no significant differences in the rhythmicity between the two groups (no group*time interaction). As expected, due to the reduced renal clearance, the overall level of C-terminal telopeptide of type I collagen and osteocalcin was higher in CKD compared to the healthy controls. The present study suggests that disturbances in the circadian rhythm of bone turnover do not explain the metabolic bone disease and increased risk of fractures in CKD.

Baseline bone turnover marker levels can predict change in bone mineral density during antiresorptive treatment in osteoporotic patients: the Copenhagen bone turnover marker study.

Anti-resorptive osteoporosis treatment might be more effective in patients with high bone turnover. In this registry study including clinical data, high pre-treatment bone turnover measured with biochemical markers was correlated with higher bone mineral density increases. Bone turnover markers may be useful tools to identify patients benefitting most from anti-resorptive treatment. INTRODUCTION: In randomized, controlled trials of bisphosphonates, high pre-treatment levels of bone turnover markers (BTM) were associated with a larger increase in bone mineral density (BMD). The purpose of this study was to examine this correlation in a real-world setting. METHODS: In this registry-based cohort study of osteoporosis patients (n = 158) receiving antiresorptive therapy, the association between pre-treatment levels of plasma C-telopeptide of type I Collagen (CTX) and/or N-terminal propeptide of type I procollagen (PINP) and change in bone mineral density (BMD) at lumbar spine, total hip, and femoral neck upon treatment was examined. Patients were grouped according to their pre-treatment BTM levels, defined as values above and below the geometric mean for premenopausal women. RESULTS: Pre-treatment CTX correlated with annual increase in total hip BMD, where patients with CTX above the geometric mean experienced a larger annual increase in BMD (p = 0.008) than patients with CTX below the geometric mean. The numerical pre-treatment level of CTX showed a similar correlation at all three skeletal sites (total hip (p = 0.03), femoral neck (p = 0.04), and lumbar spine (p = 0.0003)). A similar association was found for PINP where pre-treatment levels of PINP above the geometric mean correlated with a larger annual increase in BMD for total hip (p = 0.02) and lumbar spine (p = 0.006). CONCLUSION: Measurement of pre-treatment BTM levels predicts osteoporosis patients' response to antiresorptive treatment. Patients with high pre-treatment levels of CTX and/or PINP benefit more from antiresorptive treatment with larger increases in BMD than patients with lower pre-treatment levels.

Association between intake of soft drinks and testicular function in young men.

STUDY QUESTION: Is intake of sugar-sweetened beverages (SSB) or artificially sweetened beverages (ASB) associated with testicular function in young men? SUMMARY ANSWER: Among young men unaware of their semen quality and reproductive hormone levels, intake of SSBs was associated with lower sperm concentration, lower total sperm count, and a lower ratio of serum inhibin-B/FSH. WHAT IS KNOWN ALREADY: SSBs may adversely impact testicular function, but results are not consistent across studies. Moreover, the associations of ASB, energy-drinks or fruit juices with testicular function are unclear. STUDY DESIGN, SIZE, DURATION: Young healthy men and unselected for fertility status men enrolled in a cross-sectional study between 2008 and 2017. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 2935 young (median age: 19 years) men enrolled in the study. Intake of SSBs, ASBs, fruit juices, and energy-drinks was assessed with a validated food frequency questionnaire. Testicular function was assessed through conventional semen quality parameters (semen volume, sperm concentration, total count, motility and morphology), testicular volume assessed with ultrasound, and serum reproductive hormone concentrations (total testosterone, free testosterone, E2, inhibin-B, LH, FSH, sex hormone-binding globulin) were measured. MAIN RESULTS AND THE ROLE OF CHANCE: In multivariable-adjusted analyses, men in the highest category of SSB intake (median: 1.1 servings (∼220 ml)/day) had a 13.2 million/ml lower median sperm concentration (95% CI: -21.0, -5.5) than non-consumers. A similar pattern was observed with total sperm count (-28 million (95% CI: -48, -9)), serum inhibin-B (-12 pg/ml (95% CI: -21, -4)), and inhibin-B/FSH ratio (-9 (95% CI: -18, 0)). The adjusted median difference in sperm concentration and inhibin-B associated with increasing SSB intake by 1 serving (∼200ml)/day at the expense of water was -3.4 million sperm/ml (95% CI: -5.8, -1.0) and -7 pg/ml (95% CI: -11, -3), respectively. LIMITATIONS, REASONS FOR CAUTION: Inferring causality is limited owing to the cross-sectional design. We adjusted for a number of potential confounders but cannot exclude that unmeasured lifestyle and behavior associated with soft drink intake is associated with testicular function in these young men. WIDER IMPLICATIONS OF THE FINDINGS: In the largest study to date, intake of SSBs was associated with lower sperm concentration, total sperm count, and serum inhibin-B/FSH ratio, consistent with a direct suppressive effect of SSB intake on testicular function among otherwise healthy men, potentially affecting fertility. However, the observed association between higher SSB intake and lower semen quality does not necessarily imply a decrease in fertility. STUDY FUNDING/COMPETING INTEREST(S): Supported by research from the Danish Council for Strategic Research (2101-08-0058), Independent Research Fund Denmark (8020-00218B), European Union (212844), the Kirsten and Freddy Johansen's Foundation (95-103-72087), the Research Fund of the Capital Region of Denmark (A6176), and the NIH (P30DK046200). The authors report no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.

Seminal plasma metabolomics profiles following long (4-7 days) and short (2 h) sexual abstinence periods.

OBJECTIVE: Metabolomic profiling of seminal plasma has been suggested as a possible approach for a fast and non-invasive male infertility evaluation diagnosis. However, metabolomics profiles in normozoospermic men have not been thoroughly investigated, and the influence of ejaculation-abstinence has not been described. To provide interim reference values and find associations between the metabolomics profiles of human seminal plasma and length of ejaculation-abstinence period in normozoospermic men. STUDY DESIGN: Semen samples collected after long (4-7 days) and short abstinence (2 h) from 31 normozoospermic males were assessed for routine quality parameters before the seminal plasma was separated by centrifugation. Metabolomics profiles of the seminal plasma were then determined using untargeted Nuclear Magnetic Resonance Spectroscopy. RESULTS: In total, 30 metabolites were identified. Pyruvate showed a higher concentration, while fructose, acetate, choline, methanol, N-acetylglucosamine, O-acetylcarnitine, uridine, and sn-glycero-3-phosphocoline showed lower concentrations in samples collected after short abstinence (vs. long). All metabolites showed lower absolute amounts (volume × concentration) following shorter abstinence. However, the lower sperm concentration in samples collected after short abstinence resulted in higher absolute amounts of pyruvate and taurine per spermatozoa: pyruvate 1.92 (1.12-3.87) vs. 1.29 (0.83-2.62) (P < 0.001) and taurine 0.58 (0.36-0.92) vs. 0.43 (0.28-0.95) (P < 0.05) ng/106 spermatozoa. Simultaneously, there was a higher percentage of progressively motile spermatozoa in samples collected after the short abstinence. CONCLUSION: The generally lower concentrations of seminal metabolites after short abstinence periods may be related to the shorter time available for secretion and collection of these metabolites by the accessory glands and the epididymides. The concomitant lower number of spermatozoa in the second ejaculate resulted in increased absolute amounts of pyruvate and taurine per spermatozoa, accompanied by increased spermatozoa motility in these samples. The simultaneous increase in percentages of motile spermatozoa and absolute amounts of pyruvate and taurine per spermatozoa after shorter abstinence might indicate that these two metabolites play a more critical role in sperm motility, which should be further investigated in future studies.

Testicular cancer survivors have shorter anogenital distance that is not increased by 1 year of testosterone replacement therapy.

STUDY QUESTION: Is anogenital distance (AGD) shorter in testicular cancer (TC) survivors than in men from the general population, and is AGD affected by testosterone replacement therapy in adulthood? SUMMARY ANSWER: AGD, measured as distance from anus to scrotum (AGDas), is shorter in TC survivors and does not change as a result of testosterone replacement therapy. WHAT IS KNOWN ALREADY: Animal studies have shown that AGD is a postnatal 'read-out' of foetal androgen action, and short AGD in male offspring is considered a sign of feminization caused by in utero disruption of the reproductive system. Likewise, measurement of AGD in human studies has suggested AGD to be part of the testicular dysgenesis syndrome hypothesis, which proposes that male reproductive disorders, such as hypospadias, cryptorchidism, some cases of impaired semen quality and TC, all share a common foetal origin. STUDY DESIGN, SIZE, DURATION: The aim was to assess AGD in men with a history of TC and controls, and furthermore to examine AGD during testosterone replacement therapy in adulthood. Study participants were TC survivors with a mild Leydig cell insufficiency who participated in a randomized double-blind study of testosterone replacement therapy versus placebo for 52 weeks (N = 69). Men from the general population were prospectively included from a study on testicular function as controls (N = 67). PARTICIPANTS/MATERIALS, SETTING, METHODS: We measured two variants of AGD; as our primary outcome the anoscrotal distance (AGDas) measured from the centre of the anus to the posterior base of the scrotum, and secondarily the anopenile distance (AGDap) measured from the anus to the cephalad insertion of the penis. Using multiple regression analysis, the mean difference in AGD between TC survivors and men from the general population was assessed, adjusted for height, BMI and examiner. Next, AGD was measured before and after 52 weeks of treatment with testosterone or placebo, and with covariance analysis differences between the two groups at follow-up was assessed after adjustment for baseline AGD, examiner, BMI and change in BMI during treatment. MAIN RESULTS AND THE ROLE OF CHANCE: TC survivors had a shorter AGDas (-0.84 cm, 95% CI: -1.31; -0.37) compared to men from the general population, and AGDas did not differ between the testosterone and placebo treated group at follow-up (0.11 cm, 95% CI: -0.22; 0.44). In contrast, AGDap was not shorter in TC survivors after adjustment (0.05 cm, 95% CI: -0.30; 0.39), and was 0.48 cm longer (95% CI: 0.13; 0.82) at follow-up in the testosterone treated compared to the placebo-treated group. LIMITATIONS, REASONS FOR CAUTION: A limitation of the study is that the number of included men was limited, and results need confirmation in a larger study. Furthermore, TC survivors were significantly older than controls. For the comparison of AGD in TC survivors and controls, it was not possible to conduct the examinations with the examiner being blinded to which group he was examining, and it cannot be excluded that this can cause a bias. WIDER IMPLICATIONS OF THE FINDINGS: The shorter AGDas in TC survivors compared to controls, which did not change upon adult testosterone replacement therapy, supports the hypothesis that reduced AGD is part of the testicular dysgenesis syndrome and may be a marker of disrupted foetal testicular development. By contrast, AGDap was not shorter in TC survivors and might be modestly sensitive to adult testosterone treatment, and thus inferior to AGDas as a constant postnatal marker of the foetal androgen environment. STUDY FUNDING/COMPETING INTEREST(S): Expenses were paid by the Department of Oncology, Copenhagen University Hospital, Rigshospitalet. Kiowa Kirin International covered expenses for Tostran and placebo. The Danish Cancer Society, The Danish Cancer Research Foundation, the Preben & Anna Simonsen Foundation, and Rigshospitalet have supported the study. L.P. was financed by the Research Fund of the Capital Region of Denmark. The authors have no competing interests. TRIAL REGISTRATION NUMBER: Part of the study is based on men participating in a randomized controlled trial registered at ClinicalTrials.gov, NCT02991209, 25 November 2016.

A Multicenter Study to Evaluate Harmonization of Assays for C-Terminal Telopeptides of Type I Collagen (ß-CTX): A Report from the IFCC-IOF Committee for Bone Metabolism (C-BM).

BACKGROUND: Biochemical bone turnover markers are useful tools to assess bone remodeling. C-terminal telopeptide of type I collagen (ß-CTX) has been recommended as a reference marker for bone resorption in research studies. METHODS: We describe the results of a multicenter study for routine clinical laboratory assays for ß-CTX in serum and plasma. Four centers (Athens GR, Copenhagen DK, Liege BE and Sheffield UK) collected serum and plasma (EDTA) samples from 796 patients presenting to osteoporosis clinics. Specimens were analyzed in duplicate with each of the available routine clinical laboratory methods according to the manufacturers' instructions. Passing-Bablok regressions, Bland-Altman plots, V-shape evaluation method, and Concordance correlation coefficient for ß-CTX values between serum and plasma specimens and between methods were used to determine the agreement between results. A generalized linear model was employed to identify possible variables that affected the relationship between the methods. Two pools of serum were finally prepared and sent to the four centers to be measured in 5-plicates on 5 consecutive days with the different methods. RESULTS: We identified significant variations between methods and between centers although comparison results were generally more consistent in plasma compared to serum. We developed univariate linear regression equations to predict Roche Elecsys®, IDS-iSYS, or IDS ELISA ß-CTX results from any other assay and a multivariable model including the site of analysis, the age, and weight of the patient. The coefficients of determination (R2) increased from approximately 0.80 in the univariate model to approximately 0.90 in the multivariable one, with the site of analysis being the major contributing factor. Results observed on the pools also suggest that long-term storage could explain the difference observed with the different methods on serum. CONCLUSION: Our results show large within- and between-assay variation for ß-CTX measurement, particularly in serum. Stability of the analyte could be one of the explanations. More studies should be undertaken to overcome this problem. Until harmonization is achieved, we recommend measuring ß-CTX by the same assay on EDTA plasma, especially for research purposes in large pharmacological trials where samples can be stored for long periods before they are assayed.

Double-dose cefuroxime concentrations in bone, synovial fluid of the knee joint and subcutaneous adipose tissue-A randomised porcine microdialysis study.

This study evaluated target tissue concentrations of double dose cefuroxime administered intravenously as either one 15 min infusion of 3000 mg (Group 1) or two single 15 min infusions of 1500 mg administered 4 h apart (Group 2). Sixteen pigs were randomised into two groups of eight. Cortical and cancellous bone, synovial fluid of the knee joint and subcutaneous adipose tissue concentrations were measured based on sampling via microdialysis. Plasma samples were collected as a reference. Comparison of the groups was based on time with concentrations above relevant minimal inhibitory concentrations (fT>MIC) of 4 µg/mL. The mean time fT>MIC (4 µg/mL) across compartments was longer for Group 2 (280-394 min) than for Group 1 (207-253 min) (p<0.01). Cortical bone showed a tendency towards longer fT>MIC (4 µg/mL) in Group 2 (280 min) than in Group 1 (207 min) (p = 0.053). Within 50 min after administration, the mean concentration of 4 µg/mL was reached in all compartments for both groups. The mean concentrations decreased below 4 µg/mL after approximately 4 h (Group 1) and 3 h (Group 2) from initiation of administration (time zero). During an 8 h interval, double-dose cefuroxime administered as 2 × 1500 mg with a 4 h interval provides longer time above MIC breakpoint for Staphylococcus aureus (4 µg/mL) than a single bolus of 3000 mg cefuroxime. To maintain sufficient tissue concentrations during longer surgeries, re-administration of cefuroxime (1500 mg) should be considered 3 h after the first administration.

Uncarboxylated matrix Gla-protein: A biomarker of vitamin K status and cardiovascular risk.

BACKGROUND: Dephosphorylated uncarboxylated matrix Gla-protein (dp-ucMGP) is a biomarker of functional vitamin K status. High plasma dp-ucMGP concentrations reflect a low vitamin K status and have been related to vascular calcification. Our aims were to assess plasma levels of dp-ucMGP and their association with cardiovascular risk in a general population. METHODS: Plasma dp-ucMGP measurements were performed using the IDS-iSYS InaKtif MGP assay in 491 consecutive participants in a Danish general population study (229 males and 262 females, aged 19-71 years). Multivariable linear and logistic regressions were used to assess the association between dp-ucMGP levels and cardiovascular risk factors. RESULTS: Mean ± standard deviation (SD) for dp-ucMGP was 465 ± 181 pmol/L, and upper 95th percentile was 690 pmol/L. In logistic regression analyses, an increase in dp-ucMGP category (<300, 300-399, 400-499, ≥500 pmol/L) was positively associated with obesity, odds ratio (OR) 2.27 (95% confidence interval (CI) 1.54-3.33), history of cardiovascular disease, OR 1.77 (CI 1.02-3.05), and above-median estimated pulse wave velocity (ePWV), OR 1.54 (CI 1.21-1.96), when adjusted for age, sex, and lifestyle factors. 1 SD increase in diastolic and systolic blood pressure (BP) corresponded to a 5.5% (CI 2.9-8.0%) and 4.7% (CI 2.1-7.4%) increase in dp-ucMGP, respectively, when adjusted for age and sex. CONCLUSION: Plasma dp-ucMGP levels were positively associated with obesity, BP, ePWV, and history of cardiovascular disease. These findings support that dp-ucMGP is a biomarker of cardiovascular risk, and that vitamin K status could play a role in vascular calcification. The strong association with obesity deserves further attention.

Harmonization of commercial assays for PINP; the way forward.

International Federation of Clinical Chemistry and Laboratory Medicine and The International Osteoporosis Foundation Joint Committee on Bone Metabolism believes that the harmonization of PINP assays is an achievable and practical goal. INTRODUCTION: In order to examine the agreement between current commercial assays, a multi-center study was performed for PINP in serum and plasma. METHODS: The automated methods for PINP (Roche Cobas and IDS iSYS) gave similar results. A significant proportional bias was observed between the two automated assays and the Orion radioimmunoassay (RIA) for PINP. RESULTS: Results from other published studies comparing PINP values among these three assays broadly support our findings. Taken together, these results confirm that harmonized PINP measurements exist between the two automated assays (Roche Cobas and IDS iSYS) when the eGFR is > 30 mL/min/1.73m2, but a significant bias exists between the Orion RIA and the two automated assays. CONCLUSION: Therefore, in subjects with normal renal function, PINP results reported by the Roche Cobas and IDS iSYS assays are similar and may be used interchangeably, and similar reference intervals and treatment targets could be applied for the two automated assays. Harmonization between the automated assays and the RIA is potentially possible with the use of common calibrators and the development of a reference method for PINP. This should also help ensure that any new commercial assay developed in the future will attain similar results. IOF and IFCC are committed to working together towards this goal with the cooperation of the reagent manufacturing industry.

Vitamin D status is not associated with reproductive parameters in young Spanish men.

BACKGROUND: Relatively low sperm count was reported among young Spanish men in 2013. Several potential culprits have been suggested as explanations for reported trends in sperm counts in Western men, including lifestyles. Although controversial, some studies suggest that semen parameters, such as low sperm motility or abnormal morphology, may be associated with low serum vitamin D levels. OBJECTIVES: To evaluate associations between semen parameters and reproductive hormones and serum 25-hydroxyvitamin D (25OHD) status in young Spanish men and to examine these associations in relation to dietary intake of vitamin D. MATERIALS AND METHODS: This cross-sectional study includes 198 university students recruited in 2010-2011 in southern Spain, who provided samples of blood and semen and food frequencies. Semen quality was evaluated by measuring volume, concentration, sperm counts, motility, and morphology, according to the WHO guidelines. Serum samples were analyzed for total 25OHD and reproductive hormones, including FSH, LH, testosterone, inhibin B, and estradiol. Dietary vitamin D intake was assessed using a validated food frequency questionnaire. Associations with semen quality and reproductive hormones were examined using linear regression, adjusting for potential confounders. RESULTS: Almost all men had adequate levels of serum vitamin D - only three men (1.5%) were vitamin D deficient (<30 nmol/L) and 17% were insufficient (<50 nmol/L). However, dietary vitamin D intakes were relatively low (below recommended 600 IU/day in 99% of men). Neither dietary intake nor serum vitamin D levels were associated with any sperm parameter or any reproductive hormone (all p ≥ 0.09). DISCUSSION: We did not observe an association between vitamin D status and any reproductive parameter in our study population. CONCLUSIONS: Our results suggest that serum vitamin D levels are sustained in Spanish men despite low dietary intake and therefore low vitamin D does not explain the poor semen quality previously observed in these young Spanish men.

Bone mineral density is preserved in men with idiopathic infertility.

BACKGROUND: Lower semen quality is associated with increased mortality and morbidity, which may include osteoporosis. OBJECTIVE: To assess whether infertile men have a lower bone mineral density (BMD) compared with fertile men at the time of fertility workup. METHODS: A total of 146 men from infertile couples with unexplained impaired semen quality, characterized by sperm concentration < 20 million/mL, progressive motility < 50% or < 12% morphologically normal spermatozoa. Men with infertility due to a genetic etiology or a condition that could cause testicular damage were excluded. A total of 271 men from couples with an ongoing naturally conceived pregnancy served as a control group. Lumbar, femoral, and total body BMD were measured by dual X-ray absorptiometry. RESULTS: Infertile men had similar BMD compared with fertile men (Beta coefficient (g/cm2 ) and 95% confidence interval for the difference between the two groups: -0.02 (-0.05; 0.01) for lumbar BMD, -0.02 (-0.05; 0.01) for femoral neck BMD, -0.01 (-0.04; 0.02) for total femur BMD, and -0.01 (-0.03; 0.01) for total body BMD). Semen parameters were not associated with BMD measurements. Furthermore, BMD did not differ between infertile men with the lowest semen quality vs. infertile men with better semen quality nor between infertile men with low testosterone vs. fertile men with normal testosterone levels. CONCLUSION: Bone mineral density is preserved in men with unexplained infertility at the time of fertility workup.

Fracture-induced changes in biomarkers CTX, PINP, OC, and BAP-a systematic review.

To assess the time from fracture until bone turnover markers (BTM), which are biochemical markers reflecting in vivo bone formation and resorptive activity, have returned to a stable level since BTM have been shown to be at least as good as bone mineral density in monitoring the effect of anti-resorptive treatment in osteoporosis. This study searched for articles in PUBMED, CINAHL, Medline, EM-BASE, and Cochrane, and identified 3486 unique articles. These articles were screened based on predefined inclusion and exclusion criteria. Seven articles addressing time to normalization of either CTX, PINP, osteocalcin, or bone-specific alkaline phosphatase after a recent fracture were identified and these were analyzed qualitatively. CTX appeared to return to baseline within 6 months. PINP appeared to return to baseline within 6 months and interestingly dip below baseline after a year. Osteocalcin was elevated throughout the first year after a fracture, with most changes in the first 6 months. Bone-specific alkaline phosphatase (BAP) was increased for up to a year, however with a discrepancy between used assays. Seven studies were identified, showing CTX and PINP to return to baseline within 6 months. OC was elevated for 12 months. BAP was increased for up to a year. However, none of these studies had fasting patients and a long follow-up period with regular measurements. The studies could indicate that the BTM CTX and PINP have returned to baseline within 6 months; however, further studies are needed assessing pre-analytical factors while having a long follow-up. Bone turnover markers appear as good as or better than bone mineral density in monitoring the effect of anti-resorptive medication in osteoporosis. This study tries to identify the time from fracture until BTM are back at baseline. Most studies did not however take pre-analytical variation into consideration. Further research is therefore needed.

History of cardiovascular disease and cardiovascular biomarkers are associated with 30-day mortality in patients with hip fracture.

Hip fractures are associated with increased mortality and it is important to identify risk factors. This study demonstrates that preexisting cardiovascular disease as well as cardiovascular biomarkers that are associated with increased 30-day mortality. These findings can be used to identify high-risk patients who might benefit from specialized care. INTRODUCTION: This study investigates the association between cardiovascular disease (CVD), cardiovascular biomarkers, and 30-day mortality following a hip fracture. METHODS: The Danish National Patient Registry was used to investigate the association between CVD and mortality following hip fracture in a nationwide population-based cohort study. In a subset of the included patients (n = 355), blood samples were available from a local biobank. These samples were used for analyzing the association between specific biochemical markers and mortality. The primary outcome was 30-day mortality. RESULTS: A total of 113,211 patients were included in the population-based cohort study. Among these, heart failure was present in 9.4%, ischemic heart disease in 15.9%, and ischemic stroke in 12.0%. Within 30 days after the hip fracture, 11,488 patients died, resulting in an overall 30-day mortality of 10.1%. The 30-day mortality was significantly increased in individuals with preexisting CVD with multivariably adjusted odds ratios of 1.69 (95% confidence interval, 1.60-1.78) for heart failure, 1.23 (1.17-1.29) for ischemic heart disease, and 1.06 (1.00-1.12) for ischemic stroke. In the local database including 355 patients, 41 (11.5%) died within 30 days. The multivariably adjusted odds ratio for 30-day mortality increased with increasing NT-proBNP (2.36 [1.53-3.64] per quartile) and decreased with increasing HDL cholesterol (0.58 [0.41-0.82] per quartile). On this basis, we established a model for predicting the probability of death based on the biochemical markers. CONCLUSION: Preexisting CVD was associated with increased 30-day mortality after a hip fracture. Furthermore, high levels of NT-proBNP and low levels of HDL cholesterol were associated with increased 30-day mortality.