866,544 research outputs found
Care coordination in bone health screening between individual behaviors and health care services among Korean-American women across three age groups
Integrated continuous care is important to prevent and treat brittle bone status in the aging process; however, minority groups often have limited access to health services. The purpose of this study was to identify the care coordination among women’s perceptions about their bone health, information from health care providers, and the results of Bone Mineral Density (BMD) tests across three age groups. The study was a cross-sectional comparative design. A total of 63 Korean American women completed both the assessment of BMD of the femoral neck and an interview survey. One’s own risks of osteoporosis, screening behaviors, and health care providers’ advice were analyzed according to three age (pre-, peri-, and post-menopausal) groups, BMD levels, and health insurance coverage. Overall, health insurance coverage and having a primary health care provider of Korean American women were 59.0% and 32.0%, respectively; 61.9% had lower than normal BMD levels, which were significantly increased by advanced age. Individual awareness of risks of osteoporosis and screening behaviors were significantly higher in peri-menopausal than in pre- and post-menopausal groups, but no differences were found in health care providers’ information. The awareness and care providers’ information by BMD level or health insurance did not differ. The findings show a discrepancy between individual perceptions and behaviors and health care providers’ recommendations regard to bone health. Health behaviors should be guided by professional health care providers. The women in the post-menopausal stage need to be educated about the high risk of osteoporosis and its management
The frequency of osteogenic activities and the pattern of intermittence between periods of physical activity and sedentary behaviour affects bone mineral content: the cross-sectional NHANES study
BACKGROUND: Sedentary behaviours, defined as non exercising seated activities, have been shown to have deleterious effects on health. It has been hypothesised that too much sitting time can have a detrimental effect on bone health in youth. The aim of this study is to test this hypothesis by exploring the association between objectively measured volume and patterns of time spent in sedentary behaviours, time spent in specific screen-based sedentary pursuits and bone mineral content (BMC) accrual in youth. METHODS: NHANES 2005–2006 cycle data includes BMC of the femoral and spinal region via dual-energy X-ray absorptiometry (DEXA), assessment of physical activity and sedentary behaviour patterns through accelerometry, self reported time spent in screen based pursuits (watching TV and using a computer), and frequency of vigorous playtime and strengthening activities. Multiple regression analysis, stratified by gender was performed on N = 671 males and N = 677 females aged from 8 to 22 years. RESULTS: Time spent in screen-based sedentary behaviours is negatively associated with femoral BMC (males and females) and spinal BMC (females only) after correction for time spent in moderate and vigorous activity. Regression coefficients indicate that an additional hour per day of screen-based sitting corresponds to a difference of −0.77 g femoral BMC in females [95% CI: -1.31 to −0.22] and of −0.45 g femoral BMC in males [95% CI: -0.83 to −0.06]. This association is attenuated when self-reported engagement in regular (average 5 times per week) strengthening exercise (for males) and vigorous playing (for both males and females) is taken into account. Total sitting time and non screen-based sitting do not appear to have a negative association with BMC, whereas screen based sedentary time does. Patterns of intermittence between periods of sitting and moderate to vigorous activity appears to be positively associated with bone health when activity is clustered in time and inter-spaced with long continuous bouts of sitting. CONCLUSIONS: Some specific sedentary pursuits (screen-based) are negatively associated with bone health in youth. This association is specific to gender and anatomical area. This relationship between screen-based time and bone health is independent of the total amount of physical activity measured objectively, but not independent of self-reported frequency of strengthening and vigorous play activities. The data clearly suggests that the frequency, rather than the volume, of osteogenic activities is important in counteracting the effect of sedentary behaviour on bone health. The pattern of intermittence between sedentary periods and activity also plays a role in bone accrual, with clustered short bouts of activity interspaced with long periods of sedentary behaviours appearing to be more beneficial than activities more evenly spread in time
Extrapancreatic actions of incretin-based therapies on bone in diabetes mellitus
Diabetes mellitus is correlated with modifications in bone microarchitectural and
mechanical strength, leading to increased bone fragility. The incretin hormones, with
a classical effect to increase insulin secretion following food ingestion, are now
postulated to have important direct effects on bone. As such, glucose-dependent
insulinotropic polypeptide (GIP) has dual actions on bone cells; enhancing bone�forming activity of osteoblasts and suppressing bone resorption by osteoclasts. The
sister incretin of GIP, glucagon-like peptide-1 (GLP-1), is also suspected to directly
influence bone health in a beneficial manner, although mechanism are less clear at
present. The physiological actions of incretins are attenuated by dipeptidyl peptidase
(DPP-4) activity and it is speculated that introduction of DPP-4 inhibitor may also
positively affect quality of the skeleton. As such, this thesis evaluates the potential
beneficial effects of a DPP-4 resistant GIP analogue, namely [D-Ala2
]GIP, on
osteoblastic-derived, SaOS-2 cells, and also preliminary in vivo studies on the impact
of genetic deficiencies of GIPRs and GLP-1Rs on bone mineral density and content.
Further studies characterised the beneficial effects of incretin-based therapies on
metabolic control, bone microstructure and bone mechanical integrity in animal
models of pharmacologically-, genetically- and environmentally-induced diabetes.
GIP and related stable analogue increased bone-forming biomarkers in SaOS-2 cells
and importantly, [D-Ala2
]GIP was shown to be more potent than native GIP.
Knockout mouse studies revealed that both GIPR and GLP-1R signaling are
important for optimum bone mass. All diabetic mouse models displayed reduced
bone mass, altered bone micromorphology and impairment of bone mechanical
strength, similar to the human situation, confirming their appropriateness. The
incretin-based therapeutics, [D-Ala2
]GIP and Liraglutide, in streptozotocin-diabetic
significantly increased bone matrix properties, indicating recovery of bone strength
at the tissue level. The beneficial effects of administration of [D-Ala2
]GIP�oxyntomodulin on bone health in db/db mice were more prominent as the Oxm
analogue did not only improve bone strength at tissue level, but also at whole-bone
level. These modifications were independent of metabolic status. Twice-daily
Exendin-4 therapy improved glycaemic control and increased work required to resist
bone fracture in high-fat fed mice. It was also established that Sitagliptin had neutral
effects on bone microstructure and mechanical strength in high-fat mice. In summary, these data demonstrate the negative impact of diabetes mellitus on normal
skeleton development and bone quality. Moreover, this thesis highlights the growing
potential of incretin-based therapies for ameliorating bone defects and improving the
increased fragility fracture risk associated with diabete
Active vitamin D (1,25-dihydroxyvitamin D) and bone health in middle-aged and elderly men: the European male aging study (EMAS)
<p>Context: There is little information on the potential impact of serum 1,25-dihydroxyvitamin D [1,25(OH)2D] on bone health including turnover.</p>
<p>Objective: The objective of the study was to determine the influence of 1,25(OH)2D and 25-hydroxyvitamin D [25(OH)D] on bone health in middle-aged and older European men.</p>
<p>Design, Setting, and Participants: Men aged 40–79 years were recruited from population registers in 8 European centers. Subjects completed questionnaires that included questions concerning lifestyle and were invited to attend for quantitative ultrasound (QUS) of the heel, assessment of height and weight, and a fasting blood sample from which 1,25(OH)2D, 25(OH)D, and PTH were measured. 1,25(OH)2D was measured using liquid chromatography tandem mass spectrometry. Bone markers serum N-terminal propeptide of type 1 procollagen (P1NP) and crosslinks (β-cTX) were also measured. Dual-energy x-ray absorptiometry (DXA) of the hip and lumbar spine was performed in 2 centers.</p>
<p>Main Outcome Measure(s): QUS of the heel, bone markers P1NP and β-cTX, and DXA of the hip and lumbar spine were measured.</p>
<p>Results: A total of 2783 men, mean age 60.0 years (SD 11.0) were included in the analysis. After adjustment for age and center, 1,25(OH)2D was positively associated with 25(OH)D but not with PTH. 25(OH)D was negatively associated with PTH. After adjustment for age, center, height, weight, lifestyle factors, and season, 1,25(OH)2D was associated negatively with QUS and DXA parameters and associated positively with β-cTX. 1,25(OH)2D was not correlated with P1NP. 25(OH)D was positively associated with the QUS and DXA parameters but not related to either bone turnover marker. Subjects with both high 1,25(OH)2D (upper tertile) and low 25(OH)D (lower tertile) had the lowest QUS and DXA parameters and the highest β-cTX levels.</p>
<p>Conclusions: Serum 1,25(OH)2D is associated with higher bone turnover and poorer bone health despite being positively related to 25(OH)D. A combination of high 1,25(OH)2D and low 25(OH)D is associated with the poorest bone health.</p>
Novel skeletal effects of glucagon-like peptide-1 (GLP-1) receptor agonists
Type 2 diabetes mellitus (T2DM) leads to bone fragility and predisposes to increased risk of fracture, poor bone healing and other skeletal complications. In addition, some anti-diabetic therapies for T2DM can have notable detrimental skeletal effects. Thus, an appropriate therapeutic strategy for T2DM should not only be effective in re-establishing good glycaemic control but also in minimising skeletal complications. There is increasing evidence that glucagon-like peptide-1 receptor agonists (GLP-1RAs), now greatly prescribed for the treatment of T2DM, have beneficial skeletal effects although the underlying mechanisms are not completely understood. This review provides an overview of the direct and indirect effects of GLP-1RAs on bone physiology, focusing on bone quality and novel mechanisms of action on the vasculature and hormonal regulation. The overall experimental studies indicate significant positive skeletal effects of GLP-1RAs on bone quality and strength although their mechanisms of actions may differ according to various GLP-1RAs and clinical studies supporting their bone protective effects are still lacking. The possibility that GLP-1RAs could improve blood supply to bone, which is essential for skeletal health, is of major interest and suggests that GLP-1 anti-diabetic therapy could benefit the rising number of elderly T2DM patients with osteoporosis and high fracture risk
A suggested prototype for assessing bone health
Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved
Bone health of middle-aged and older surfers
Purpose: Given the lack of research investigating surfing and bone health, we aimed to assess the bone mineral density (BMD) of middle-aged and older surfers.
Patients and methods: In a cross-sectional observational design, we compared a group of middle-aged and older surfers to a group of non-surfers, age- and sex-matched controls. Participants were males, aged between 50 and 75 years. Volunteers were assessed for body mass index, bone-specific physical activity questionnaire (BPAQ) scores, daily calcium intake, and alcohol intake. Primary outcomes included BMD at the femur and lumbar spine (LS), and T-score, assessed via dual-energy X-ray absorptiometry. Bone biomarkers were also analyzed.
Results: A total of 104 participants (59 surfers and 45 controls) were assessed. Groups were similar with regards to all demographic characteristics except for percentage of lean mass (higher in surfers, mean difference [MD] +2.57%; 95% CI 0.05–5.09; p=0.046) and current BPAQ score (lower in surfers; MD −0.967; 95% CI −0.395 to −1.539; p=0.001). Surfers had a mean surfing experience of 41.2 (SD ±11.8) years and mean surfing exposure of 26.9 (SD ±15.0) hours/month. Controls were divided into two groups, according to their main physical activity: weight-bearing/high intensity (WBHI) and non-weight-bearing/low intensity (NWBLI). When compared to NWBLI controls, surfers had higher LS BMD (MD +0.064; 95% CI 0.002–0.126; p=0.041) and higher T-score (MD +0.40; 95% CI 0.01–0.80; p=0.042); however, surfers had a lower T-score than the WBHI group (MD −0.52; 95% CI −0.02 to −1.0; p=0.039). No other differences were found between groups.
Conclusion: The findings of this study support our hypothesis that regular surfing may be an effective physical activity for middle-aged and older men to decrease bone deterioration related to aging, as we identified positive results for surfers in relation to primary outcomes.Full Tex
Effects of water-based exercise on bone health of middle-aged and older adults:A systematic review and meta-analysis
Background: Age-related bone loss is a major health concern. Only exercises associated with high-impact and mechanical loading have been linked to a positive effect on bone turnover; however, these types of exercises may not always be appropriate for middle-aged and older adults due to physical decline or chronic disorders such as osteoarthritis. Water-based exercise (WBE) has been shown to affect different components of physical fitness, has lower risks of traumatic fracture, and applies less stress to joints. However, the effects of WBE on bone health are unclear.
Objective: This study aimed to explore whether WBE is effective in preventing age-related bone deterioration in middle-aged and older adults.
Methods: A search of relevant databases and the references of identified studies was performed. Critical narrative synthesis and meta-analyses were conducted.
Results: Eleven studies, involving 629 participants, met all inclusion criteria. All participants were postmenopausal women. Eight studies compared WBE to a sedentary control group, and four studies had land-based exercise (LBE) participants as a comparison group. Meta-analyses revealed significant differences between WBE and control group in favor of WBE for changes in bone mineral density (BMD) at the lumbar spine (mean difference [MD] 0.03 g/cm2 ; 95% confidence interval [CI]: 0.01 to 0.05) and femoral neck (MD 0.04 g/cm2 ; 95% CI: 0.02 to 0.07). Significant differences were also revealed between WBE and LBE in favor of LBE for changes in lumbar spine BMD (MD -0.04 g/cm2 ; 95% CI: -0.06 to -0.02). However, there was no significant difference between WBE and LBE for changes in femoral neck BMD (MD -0.03 g/cm2 ; 95% CI: -0.08 to 0.01).
Conclusion: WBE may have benefits with respect to maintaining or improving bone health in postmenopausal women but less benefit when compared to LBE. Further research is required on this topic
Sclerostin inhibition alleviates breast cancer-induced bone metastases and muscle weakness
Breast cancer bone metastases often cause a debilitating non-curable condition with osteolytic lesions, muscle weakness and a high mortality. Current treatment comprises chemotherapy, irradiation, surgery and anti-resorptive drugs that restrict but do not revert bone destruction. In metastatic breast cancer cells, we determined the expression of sclerostin, a soluble Wnt inhibitor that represses osteoblast differentiation and bone formation. In mice with breast cancer bone metastases, pharmacological inhibition of sclerostin using an anti-sclerostin antibody (Scl-Ab) reduced metastases without tumor cell dissemination to other distant sites. Sclerostin inhibition prevented the cancer-induced bone destruction by augmenting osteoblast-mediated bone formation and reducing osteoclast-dependent bone resorption. During advanced disease, NF-κB and p38 signaling was increased in muscles in a TGF-β1-dependent manner, causing muscle fiber atrophy, muscle weakness and tissue regeneration with an increase in Pax7-positive satellite cells. Scl-Ab treatment restored NF-κB and p38 signaling, the abundance of Pax7-positive cells and ultimately muscle function. These effects improved the overall health condition and expanded the life span of cancer-bearing mice. Together, these results demonstrate that pharmacological inhibition of sclerostin reduces bone metastatic burden and muscle weakness with a prolongation of the survival time. This might provide novel options for treating musculoskeletal complications in breast cancer patients.
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