Bone turnover is adequately suppressed in osteoporotic patients treated with bisphosphonates in daily practice

Serum levels of bone turnover markers including calculation of Z-scores: Data from a Dutch healthy reference cohort

Introduction

Bone turnover markers (BTM) are biochemical compounds reflecting different stages of bone metabolism. Their levels change with age and differ between males and females. This makes clinical interpretation and comparison more difficult. Therefore, our aim was to establish BTM reference values which can be used to calculate Z-scores for use in daily clinical practice.

Methods

Serum markers of collagen resorption, bone formation/regulation, collagen formation and bone mineralization (sCTX, OC, PINP and BALP, respectively) were measured in non-fasting volunteers without bone-related abnormalities. Raw data was plotted and gender-specific age cohorts were established with their respective means and standard deviations (SD). Z-scores can be calculated using these reference values to correct for the influence of age and gender on BTM.

Results

In total, 856 individuals were included of which 486 (57 %) were female. Individuals were aged between 7 and 70 years. Highest serum levels of BTM were found in childhood and puberty. Peak levels are higher in boys than girls and prevail at later ages. In adults, BTM levels decrease before reaching stable nadir levels. In adults, 10-year reference cohorts with means and SD were provided to calculate Z-scores.

Conclusion

With our data, Z-scores of sCTX, OC, PINP and BALP can be calculated using reference categories (for age and gender) of Caucasian healthy volunteers. Clinicians can use BTM Z-scores to determine whether there are changes in bone turnover physiology beyond those expected during aging. BTM Z-scores facilitate harmonization of data interpretation in daily clinical practice and research.

Efficacy of bisphosphonate therapy on postmenopausal osteoporotic women with and without diabetes: a prospective trial

BACKGROUND

The co-occurrence of diabetes and osteoporosis is common in postmenopausal women. For the treatment of postmenopausal osteoporosis, current guidelines recommend initial treatment with bisphosphonates, but it is unclear whether bisphosphonates provide a similar degree of therapeutic efficacy in patients with diabetes. This study sought to compare the efficacy of monthly oral ibandronate for retaining bone mineral density (BMD) in diabetic and non-diabetic postmenopausal women with osteoporosis.

METHODS

Postmenopausal osteoporotic women with or without diabetes were enrolled in this study from three hospitals in an open-label approach from 2018 to 2020. Each group of patients received oral ibandronate 150 mg once monthly for 1 year. BMD, trabecular bone score (TBS), serum C-terminal telopeptide of type I collagen (CTx) and procollagen type 1 N-terminal propeptide (P1NP) were evaluated prospectively. Treatment-emergent adverse events and changes in glucose metabolism during drug use were also monitored.

RESULTS

Among the 120 study participants, 104 (86.7%) completed the study. Following 1 year of treatment, BMD increased by 3.41% vs. 3.71% in the lumbar spine, 1.30% vs. 1.18% in the femur neck, and 1.51% vs. 1.58% in the total hip in the non-diabetes and diabetes groups, respectively. There were no significant differences in BMD changes between the groups, and the differences in CTx or P1NP changes between groups were not significant. We did not observe any significant differences in baseline TBS values or the degree of change between before and after 1 year of ibandronate treatment in either group in this study. A total of 11 adverse events (9.2%) that recovered without sequelae occurred among the 120 included patients, and there was no significant difference in the frequency of adverse events between the groups (p = 0.862). The changes in fasting glucose and glycated hemoglobin levels between before and after treatment were not significant in the diabetic group.

CONCLUSIONS

Bisphosphonate therapy showed similar increases in BMD and decreases in CTx and P1NP of postmenopausal women with and without diabetes. Monthly oral ibandronate can be a safe and effective therapeutic option in postmenopausal osteoporosis patients with type 2 diabetes.

TRIAL REGISTRATION

NCT number: NCT05266261, Date of registration: 04 March 2022.

Can bone turnover markers help to define the suitability and duration of bisphosphonate drug holidays?

BACKGROUND

On stopping bisphosphonate treatment, bone resorption may increase before evidence of a decrease in bone density. Offset of bisphosphonate effect may therefore be monitored by measuring C-terminal telopeptide (CTX) following long-term bisphosphonate treatment to inform clinical decisions on drug holiday.

METHODS

Retrospective analysis of 158 patients (83% female, mean age 71 years) starting a drug holiday had plasma CTX measured at discontinuation (baseline), n=138 and 4 months and n=136, and 12 months (n=100). Premenopausal mean CTX levels and the least significant change (LSC) detectable were used to define target thresholds for bone turnover.

RESULTS

Following long-term bisphosphonate treatment (69% alendronic acid, 33% risedronate, mean duration 8 years SD 2.7), 32% patients had CTX above target (0.19 μg/L). In those with baseline CTX below threshold, 28% increased CTX to >0.19 μg/L and > LSC (0.06 μg/L) by 4 months (mean CTX increase 0.05 μg/L [95% confidence interval (CI): 0.04-0.06; p<0.0001]) and 53% by 12 months (mean CTX increase 0.09 μg/L [95% CI: 0.07-0.10; p<0.0001]), whilst 47% had no detectable changes in CTX over 12 months.

CONCLUSION

A third of patients showed inadequate suppression of CTX at baseline, despite long-term bisphosphonate treatment. Drug holiday may not be appropriate for this group, showing a poor therapeutic response or poor adherence. For more than a quarter of patients, bisphosphonate effects were wearing off at 4 months and around half by 12 months. We suggest CTX monitoring could identify those not experiencing a sustained bisphosphonate effect, including poorly adherence to therapy, and may be used during a drug holiday to prompt recommencement of therapy.

Clinical utility of bone markers in various diseases

Measurements of bone markers (BMs) in peripheral blood or urine are a pivotal part of bone research within modern clinical medicine. In recent years the use of BMs increased substantially as they can be useful either to diagnose bone (related) disease and to follow its natural history, but also to monitor the effects of interventions. However, the use of BMs is still complicated mainly due to (pre)analytical variability of these substances, limited accessibility of assays, variable cut-off values in different countries and laboratories and heterogeneous results with regard to clinical implications of measuring BMs in several studies. This review will provide the clinician with a practical guide, based on current evidence, in which circumstances to test which bone markers for optimal diagnostic purposes, in order to improve patient care in different areas of bone diseases including Paget's disease, primary osteoporosis, tumor induced osteomalacia, hypophosphatemic rickets, van Buchem disease, chronic kidney disease, rheumatoid arthritis, neoplasma/multiple myeloma, type 2 diabetes mellitus and primary hyperparathyroidism. The clinician should consider fasting state, recent fractures, aging, menopausal status, concomitant liver and kidney disease when ordering and interpreting BM measurements as these factors might result in misleading BM concentrations. We found that BMs are clearly useful in the current diagnosis of tumor induced osteomalacia, van Buchem disease, Paget's disease and hypophosphatemic rickets. In addition, BMs are useful to monitor disease activity in chronic kidney disease, Paget's disease and are useful to monitor treatment adherence in osteoporosis.

A dedicated Fracture Liaison Service telephone program and use of bone turnover markers for evaluating 1-year persistence with oral bisphosphonates

Telephone call intervention did not improve alendronate persistence in Fracture Liaison Service (FLS) patients in this study. A bone turnover marker cut-off point for alendronate persistence is proposed for individual FLS patients.

INTRODUCTION

FLS aims to prevent subsequent fractures, which should include improving patients' persistence with prescribed oral bisphosphonates. We studied the influence of telephone calls and the predictive value of changes in bone turnover markers (BTMs) for evaluating persistence with alendronate.

METHODS

Postmenopausal women with a recent fracture and osteoporosis who started alendronate were randomized to receive three phone calls (PC) (after 1, 4, and 12 months) or no phone calls (no PC). s-CTX and P1NP were measured at baseline and after 3, 6, 9, and 12 months. As a reference group, 30 postmenopausal osteopenic patients with a recent fracture were analyzed as well. Persistence was assessed using the Dutch National Switch Point Pharmacies-GPs database and cross-referenced with PC, no PC, and BTM changes. Cut-off values of BTMs were calculated based on least significant change (LSC) and also on underrunning median values of the untreated osteopenic postmenopausal reference group with a recent fracture.

RESULTS

Out of 119 patients, 93 (78%) completed 12 months follow-up (45 PC and 48 no PC). Mean age was 69 years. Persistence was similar in PC and no PC participants. The cut-off value > 29% (< 415 ng/L) as LSC of s-CTX and > 36% (< 53.1 μg/L) as LSC of P1NP was determined optimally showing alendronate persistence after 1 year (being 93 and 88%, respectively).

CONCLUSIONS

In this context, telephone calls did not improve persistence. In around 90% of patients, 1-year alendronate persistence was confirmed by achieving LSC of s-CTX and of P1NP at 12 months.

Antiosteoporotic activity of Salvadora persica sticks extract in an estrogen deficient model of osteoporosis

Objectives

The effect of Salvadora persica sticks on prevention of tooth decay is well established, but the effect of S. persica stick extract (SPE) on the prevention/treatment of osteoporosis has not been studied. The purpose of this study is to provide baseline information of the effectiveness of SPE on ovariectomized (OVX) rat model of osteoporosis.

Methods

SPE was administered at 50, 150, and 300 mg/d orally to OVX rats for 16 weeks. Serum osteocalcin, alkaline phosphatase, calcium, and phosphorus, and urinary deoxypyridinoline, calcium, and phosphorus were measured. Bone mineral density (BMD), 3-point bending test, and histomorphometric characteristics of the femoral bone were also examined.

Results

SPE at doses of 150 and 300 mg/d, but not 50 mg/d, significantly prevented bone loss in OVX rats as proved by decreased biochemical markers of bone resorption and increased BMD and biomechanical indices of the femoral bone.

Conclusions

This study confirms a dose-dependent protective action of SPE on rat OVX model of osteoporosis. This effect needs further investigation at the molecular and clinical levels to provide a natural and cost-effective alternative for the management of postmenopausal osteoporosis.

Decrease of Markers Related to Bone Erosion in Serum of Patients with Musculoskeletal Disorders after Serial Low-Dose Radon Spa Therapy

Musculoskeletal disorders (MSDs) are the most frequent cause of disability in Europe. Reduced mobility and quality of life of the patients are often associated with pain due to chronic inflammation. The inflammatory process, accompanied by a destruction of the cartilage and bone tissue, is discussed as a result of (A) the infiltration of immune cells into the joints, (B) an altered homeostasis of the joint cavity (synovium) with a critical role of bone remodeling cells, and (C) release of inflammatory factors including adipokines in the arthritic joint. In addition to the classical medication, low-dose radiation therapy using photons or radon spa treatments has shown to reduce pain and improve the mobility of the patients. However, the cellular and molecular mechanisms of anti-inflammatory effects of radon are yet poorly understood. We analyzed blood and serum samples from 32 patients, suffering from MSDs, who had been treated in the radon spa in Bad Steben (Germany). Before and after therapy, we measured the levels of markers related to bone metabolism (collagen fragments type-1, cartilage oligomeric matrix protein, receptor activator of NFκB ligand, and osteoprotegerin) in the serum of patients. In addition, adipokines related to inflammation (visfatin, leptin, resistin, and adiponectin) were analyzed. Some of these factors are known to correlate with disease activity. Since T cells play an important role in the progression of the disease, we further analyzed in blood samples the frequency of pro- and anti-inflammatory T cell subpopulations (CD4⁺IL17⁺ T cells and CD4⁺FoxP3⁺ regulatory T cells). Overall, we found a decrease of collagen fragments (CTX-I), indicating decreased bone resorption, presumably by osteoclasts, in the serum of MSD patients. We also observed reduced levels of visfatin and a consistent trend toward an increase of regulatory T cells in the peripheral blood, both indicating attenuation of inflammation. However, key proteins of bone metabolism were unchanged on a systemic level, suggesting that these factors act locally after radon spa therapy of patients with MSDs.

Combined aerobic and resistance training improves bone health of female cancer survivors

INTRODUCTION

Cancer pathogenesis and resulting treatment may lead to bone loss and poor skeletal health in survivorship. The purpose of this investigation was to evaluate the influence of 26 weeks of combined aerobic and resistance-training (CART) exercise on bone mineral density (BMD) in a multi-racial sample of female cancer survivors.

METHODS

Twenty-six female cancer survivors volunteered to undergo CART for 1 h/day, 3 days/week, for 26 weeks. The Improving Physical Activity After Cancer Treatment (IMPAACT) Program involves supervised group exercise sessions including 20 min of cardiorespiratory training, 25 min of circuit-style resistance-training, and 15 min of abdominal exercises and stretching. BMD at the spine, hip, and whole body was assessed using dual-energy X-ray absorptiometry (DXA) before and after the intervention. Serum markers of bone metabolism (procollagen-type I N-terminal propeptide, P1NP, and C-terminal telopeptides, CTX) were measured at baseline, 13 weeks, and at study completion.

RESULTS

Eighteen participants, with the average age of 63.0 ± 10.3 years, completed the program. Mean duration since completion of cancer treatment was 6.2 ± 10.6 years. Paired t-tests revealed significant improvements in BMD of the spine (0.971 ± 0.218 g/cm² vs. 0.995 ± 0.218 g/cm², p = 0.012), hip (0.860 ± 0.184 g/cm² vs. 0.875 ± 0.191 g/cm², p = 0.048), and whole body (1.002 ± 0.153 g/cm² vs. 1.022 ± 0.159 g/cm², p = 0.002). P1NP declined 22% at 13 weeks and 28% at 26 weeks in comparison to baseline (p < 0.01) while CTX showed a non-significant decrease of 8% and 18% respectively.

CONCLUSIONS

We report significant improvements in BMD at the spine, hip, and whole body for female cancer survivors who completed 26 weeks of CART. This investigation demonstrates the possible effectiveness of CART at improving bone health and reducing risk of osteoporosis for women who have completed cancer treatment. The IMPAACT Program appears to be a safe and feasible way for women to improve health after cancer treatment.

The use of biochemical markers of bone turnover in the clinical management of primary and secondary osteoporosis

The purpose of the present study was to examine of the current role of bone turnover markers (BTMs) in the management of osteoporosis. Perusal of the literature examines the available evidence for the utility of BTMs for decision to treat and for the monitoring of treatment for osteoporosis. There is no evidence for the use of BTMs for fracture risk calculation, decision to treat or for treatment selection. A very abnormal BTM value may be a clue to the presence of bone pathology other than uncomplicated osteoporosis. Whilst changes to BTMs following various osteoporosis treatments are well defined, their utility in monitoring individual patients has been less well established. Some fracture outcome-based data exist for the use of u-NTX target of <21 nmol BCE/mmol for antiresorptive therapy; the equivalent s-CTX level is ~250 ng/L. Suboptimal BTM response to treatment may indicate non-compliance or the presence of secondary causes of osteoporosis which may need addressing. Studies are needed to establish treatment targets based on fracture outcomes for commonly used BTMs for each established osteoporosis therapy.

Clonidine increases bone resorption in humans

SUMMARY

Inhibition of sympathetic signaling to bone reduces bone resorption in rodents. In contrast, we show that pharmacological reduction of the sympathetic tone increases bone resorption in humans in vivo. This effect does not appear to be mediated via a direct pharmacological effect on the osteoclast.

INTRODUCTION

Inhibition of sympathetic signaling to bone reduces bone resorption in rodents. It is uncertain whether a similar role for the sympathetic nervous system exists in humans. The sympathetic tone can be reduced by clonidine, which acts via alpha-2-adrenergic receptors in the brainstem. Our objective was to determine the effect of clonidine on bone turnover in humans.

METHODS

The acute effect of a single oral dose of 0.3 mg clonidine on serum bone turnover markers (C-terminal cross-linking telopeptides of collagen type I (CTx), a marker for bone resorption, and procollagen type 1 N propeptide (P1NP), a marker for bone formation) was determined in a randomized crossover design in 12 healthy volunteers, aged 18-70 years. In addition, we assessed the effect of clonidine on the number of tartrate-resistant acid phosphatase-positive multinucleated cells (TRAcP(+) MNCs) and bone resorption.

RESULTS

CTx concentrations increased after clonidine treatment compared to the control condition (p = 0.035). P1NP concentrations were not affected by clonidine (p = 0.520). In vitro, clonidine had no effect on the number of TRAcP(+) MNCs (p = 0.513) or on bone resorption (p = 0.996).

CONCLUSIONS

We demonstrated that clonidine increases bone resorption in humans in vivo. This effect does not appear to be mediated via a direct effect on the osteoclast.

Velaglucerase alfa (VPRIV) enzyme replacement therapy in patients with Gaucher disease: Long-term data from phase III clinical trials

Type 1 Gaucher disease is an inherited lysosomal enzyme deficiency with variable age of symptom onset. Common presenting signs include thrombocytopenia, anemia, hepatosplenomegaly, bone abnormalities, and, additionally in children, growth failure. Fifty-seven patients aged 3–62 years at the baseline of two phase III trials for velaglucerase alfa treatment were enrolled in the single extension study. In the extension, they received every-other-week velaglucerase alfa intravenous infusions for 1.2–4.8 years at 60 U/kg, although 10 patients experienced dose reduction. No patient experienced a drug-related serious adverse event or withdrew due to an adverse event. One patient died following a convulsion that was reported as unrelated to the study drug. Only one patient tested positive for anti-velaglucerase alfa antibodies. Combining the experience of the initial phase III trials and the extension study, significant improvements were observed in the first 24 months from baseline in hematology variables, organ volumes, plasma biomarkers, and, in adults, the lumbar spine bone mineral density Z-score. Improvements were maintained over longer-term treatment. Velaglucerase alfa had a good long-term safety and tolerability profile, and patients continued to respond clinically, which is consistent with the results of the extension study to the phase I/II trial of velaglucerase alfa. EudraCT number 2008-001965-27; http://www.clinicaltrials.gov identifier NCT00635427. Am. J. Hematol. 90:584–591, 2015. © 2015 Wiley Periodicals, Inc.

Evaluation of urinary N-telopeptide of type I collagen measurements in the management of osteoporosis in clinical practice

We measured urinary N-telopeptide of type I collagen (U-NTX) to monitor response to bisphosphonates for osteoporosis. Decrease in U-NTX was associated with increase in spine bone density. A lesser response in U-NTX was more likely in those with secondary osteoporosis or with poor compliance. U-NTX may be a useful early indicator of treatment non-compliance or secondary osteoporosis.

INTRODUCTION

This study aims to determine the utility of the bone resorption marker, U-NTX, in the clinical setting, to monitor the response to bisphosphonate therapy (alendronate and risedronate) for osteoporosis.

METHODS

A retrospective evaluation of data collected as part of the bone turnover marker monitoring service in the Metabolic Bone Centre, Sheffield, UK. Treatment compliance, underlying causes of osteoporosis, change in U-NTX/creatinine (Cr) at 4 months and change in spine and hip bone mineral density (BMD) by dual-energy X-ray absorptiometry were recorded. Treatment response was defined as either a change in U-NTX/Cr greater than a pre-defined least significant change (LSC) of 54 % or to within the lower half of a pre-defined pre-menopausal reference interval (≤ 30 nM BCE/mmol Cr).

RESULTS

A greater decrease in U-NTX/Cr at 4 months was associated with a greater increase in spine BMD at 18 months (r = -0.33; P < 0.0001, Pearson's correlation). The mean U-NTX/Cr at 4 months was higher in patients with secondary osteoporosis compared with those with primary osteoporosis (P < 0.01, ANOVA). A lesser response in U-NTX/Cr increased the likelihood of secondary osteoporosis or poor treatment compliance (P = 0.04, Fisher's exact test). A lack of response in U-NTX/Cr to within the lower half of the reference interval was a better indicator of secondary osteoporosis and treatment non-compliance than a change in U-NTX/Cr greater than LSC.

CONCLUSIONS

Treatment monitoring using U-NTX/Cr has a place in clinical practice for the early identification of non-compliance or presence of secondary osteoporosis.

Distribution of serum βCTX in a population-based study of postmenopausal women taking into account different anti-osteoporotic therapies (the FRODOS Cohort)

This cross-sectional study evaluated the distribution of serum cross-linked C-telopeptides of collagen type I (βCTXs) in postmenopausal women, the characteristics of bone remodeling, and the factors influencing this bone marker, especially the use of anti-osteoporotic drugs. Women (n = 4,175) aged 59-70 years randomly selected from the community were invited to participate, measuring βCTXs and lumbar and femoral bone mineral density at recruitment. Risk factors for osteoporosis and the use of anti-osteoporotic treatment were collected with a structured questionnaire. We evaluated the percentage of women with increased (βCTXs >0.620 ng/mL) and decreased bone turnover (βCTXs <0.100 ng/mL) and those reaching the so-called treatment target (values of βCTXs within the lower half of the reference range for healthy young premenopausal women). Two thousand nine hundred sixty-eight women (70 %) participated (2,405 non-treated and 563 treated). Increased and decreased bone turnover was observed in 16.4 and 1.8 %, respectively, of non-treated women with significant differences compared with treated women (9.7 and 14.2 %, respectively, p < 0.001); 28 % of non-treated osteoporotic individuals had increased bone turnover versus 14 % of osteopenic participants and 8.8 % of women with normal bone density (p < 0.001). Women receiving bisphosphonates presented the highest percentages of decreased bone turnover (27 %) and βCTXs (43 %) within the treatment target. Increased bone turnover is observed in 16.4 % of non-treated postmenopausal women and is more frequent in individuals with osteoporosis, whereas decreased bone turnover is unusual. Most participants taking bisphosphonates had values within the treatment target, but nearly one quarter had decreased bone turnover.