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1.
Osteoporos Int ; 33(9): 1895-1907, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35701629

RESUMEN

This study identified the costs and health-related quality of life impacts of several post-fracture multidisciplinary care pathways specific to individual skeletal site (hip, distal forearm, vertebrae, humerus). These care pathways may assist healthcare providers in allocating resources for osteoporotic fractures in more effective and cost-efficient ways. INTRODUCTION: This micro-costing study was undertaken to provide the estimated healthcare costs of several fracture site-specific health service use pathways associated with different trajectories of health-related quality of life (HRQoL) 12-months post-fracture. METHODS: The study included 4126 adults aged ≥ 50 years with a fragility fracture (1657 hip, 681 vertebrae, 1354 distal forearm, 434 humerus) from the International Costs & Utilities Related to Osteoporotic fractures Study (ICUROS). ICUROS participants were asked to recall the frequency and duration (where applicable) of their health and community care service use at 4- and 12-month follow-up visits. Patient-level costs were identified and aggregated to determine the average cost of healthcare use related to the fracture in each care pathway (presented in Australian 2021 dollars). Mean cost differences were calculated and analysed using a one-way analysis of variance (ANOVA) and post hoc Bonferroni correction to determine any statistically significant differences. RESULTS: The total direct cost of fractures was estimated at $89564, $38926, $18333, and $38461AUD per patient for hip, vertebral, wrist, and humeral participants, respectively. A Kruskal-Wallis test yielded a statistically significant difference in cost values between most care pathways (p < 0.001). Of the 20 care pathways, those associated with recovery of HRQoL had lower mean costs per patient across each fracture site. CONCLUSIONS: This study identified the costs and HRQoL impacts of several multidisciplinary care pathways for individual fracture sites based on the health service utilization of an international cohort of older adults. These care pathways may assist healthcare providers in allocating resources for fragility fractures in more effective and cost-efficient ways.


Asunto(s)
Fracturas de Cadera , Fracturas Osteoporóticas , Anciano , Australia , Vías Clínicas , Costos de la Atención en Salud , Fracturas de Cadera/terapia , Humanos , Fracturas Osteoporóticas/terapia , Calidad de Vida
2.
Osteoporos Int ; 33(1): 67-75, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34235548

RESUMEN

In this study of 695 Australian older adults (aged ≥50 years), we found that men and women had a similar trajectory of health-related quality of life (HRQoL) recovery following fragility fracture at any skeletal site. These results provide us with critical knowledge that improves our understanding of health outcomes post-fracture. INTRODUCTION: Mortality is higher in men than that in women following a fragility fracture, but it is unclear whether recovery of patient-reported outcomes such as health-related quality of life (HRQoL) differs between sexes. This study aimed to identify sex differences in HRQoL recovery 12 months post-fracture. METHODS: Data were from the Australian arm of the International Costs and Utilities Related to Osteoporotic Fractures Study (AusICUROS). Participants recruited to AusICUROS were adults aged ≥50 years who sustained a fragility fracture. HRQoL was measured using the EQ-5D-3L at three time-points post-fracture: within 2 weeks (including pre-fracture recall) and at 4 and 12 months. Multivariate logistic regression analyses were undertaken, adjusting for confounders including age, education, income, and healthcare utilization post-fracture. RESULTS: Overall, 695 AusICUROS participants (536 women, 77.1%) were eligible for analysis with fractures at the hip (n = 150), distal forearm (n = 261), vertebrae (n = 61), humerus (n = 52), and other skeletal sites (n = 171). At the time of fracture, men were younger, reported a higher income, and were more likely to be employed, compared with women. For all fracture sites combined, there were no differences between men and women in recovery to pre-fracture HRQoL at 12-month follow-up (adjusted OR = 1.09; 95% CI: 0.75-1.61). When stratified by fracture site, no significant sex differences were seen for hip (OR = 1.02; 95% CI: 0.42-2.52), distal forearm (OR = 1.60; 95% CI: 0.68-3.78), vertebral (OR = 2.28; 95% CI: 0.61-8.48), humeral (OR = 1.62; 95% CI: 0.16-9.99), and other fractures (OR = 1.00; 95% CI: 0.44-2.26). CONCLUSION: Community-dwelling men and women who survived the 12 months following fragility fracture had a similar trajectory of HRQoL recovery at any skeletal site.


Asunto(s)
Fracturas de Cadera , Fracturas Osteoporóticas , Anciano , Australia/epidemiología , Femenino , Humanos , Vida Independiente , Masculino , Calidad de Vida , Caracteres Sexuales
3.
Osteoporos Int ; 32(10): 2073-2081, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33856500

RESUMEN

The Australian Health Economics Model of Osteoporosis (AusHEMO) has shown good face, internal and cross validities, and can be used to assist healthcare decision-making in Australia. PURPOSE: This study aimed to document and validate the risk engine of the Australian Health Economics Model of Osteoporosis (AusHEMO). METHODS: AusHEMO is a state-transition microsimulation model. The fracture risks were simulated using fracture incidence rates from the Dubbo Osteoporosis Epidemiology Study. The AusHEMO was validated regarding its face, internal and cross validities. Goodness-of-fit analysis was conducted and Lin's coefficient of agreement and mean absolute difference with 95% limits of agreement were reported. RESULTS: The development of AusHEMO followed general and osteoporosis-specific health economics guidelines. AusHEMO showed good face validity regarding the model's structure, evidence, problem formulation and results. In addition, the model has been proven good internal and cross validities in goodness-of-fit test. Lin's coefficient was 0.99, 1 and 0.94 for validation against the fracture incidence rates, Australian life expectancies and residual lifetime fracture risks, respectively. CONCLUSIONS: In summary, the development of the risk engine of AusHEMO followed the best practice for osteoporosis disease modelling and the model has been shown to have good face, internal and cross validities. The AusHEMO can be confidently used to predict long-term fracture-related outcomes and health economic evaluations when costs data are included. Health policy-makers in Australia can use the AusHEMO to select which osteoporosis interventions such as medications and public health interventions represent good value for money.


Asunto(s)
Osteoporosis , Fracturas Osteoporóticas , Australia/epidemiología , Análisis Costo-Beneficio , Humanos , Modelos Económicos , Osteoporosis/epidemiología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología
4.
Osteoporos Int ; 31(12): 2287-2302, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32662035

RESUMEN

A systematic review of prediction models/questionnaires developed to identify people with deficient/insufficient vitamin D status shows the potential of self-reported information to estimate vitamin D status. The objective is to identify and compare existing screening tools, developed to identify vitamin D deficiency or insufficiency in adults. A systematic search of literature was conducted using MEDLINE, Scopus, Web of Science and CINAHL databases. Risk of bias and applicability concerns were assessed by quality assessment of diagnostic accuracy studies (QUADAS-2). Data were extracted on socio-demographic, anthropometric, risk factors, serum 25 hydroxyvitamin D [25(OH)D] levels, statistical methods and predictive ability. A total of 12 studies were considered for inclusion for this systematic review after screening of 4851 abstracts and 15 full-text articles. Ten of twelve studies developed prediction models and 2 studies developed questionnaires. The majority of studies had low risk of bias and applicability as assessed by QUADAS-2. All studies included only self-reported predictors of vitamin D status in their final models and development of scores. Sunlight exposure and related factors were important significant contributors to the predictive ability of the models and/or questionnaires. Sensitivity and specificity of the prediction models or questionnaires ranged from 55 to 91% and 35 to 84%, respectively. Six out of twelve studies converted final models to scores associated with vitamin D status. There was no evidence that any of these existing tools have been translated into clinical practice. The prediction models or questionnaires identified in this systematic review were moderately sensitive and specific for identifying people with vitamin D deficiency or insufficiency. The substantial contribution of sunlight exposure to the prediction of vitamin D status highlights the importance of including this information when developing vitamin D screening tools.


Asunto(s)
Deficiencia de Vitamina D , Vitamina D , Adulto , Humanos , Autoinforme , Encuestas y Cuestionarios , Deficiencia de Vitamina D/diagnóstico , Deficiencia de Vitamina D/epidemiología , Vitaminas
5.
Br J Dermatol ; 180(4): 821-827, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-29947106

RESUMEN

BACKGROUND: Patients with atopic dermatitis (AD) often report that stress aggravates their itch. However, no study has investigated if and how acute stress influences itch sensation and scratching behaviour in these patients. OBJECTIVES: We evaluated the impact of acute stress on experimentally induced cowhage itch perception and scratching behaviour in 16 healthy subjects and 15 patients with AD. METHODS: The Trier Social Stress Test (TSST) was used to induce acute stress. The itch sensation, provoked by applying cowhage to the forearms, and off-site scratching behaviour (not directed at the cowhage application site) were compared before and after performing the TSST or the control condition (watching a video of landscape scenes). RESULTS: In patients with AD, stress induced by TSST caused a significant reduction of cowhage-evoked itch but significantly increased off-site scratching behaviour. Such changes in itch perception and scratching behaviour were not observed in healthy controls. In addition, a significant positive correlation was noted between stress induced by TSST and clinical severity of eczema. CONCLUSIONS: We speculate that psychological stress increases spontaneous scratching in patients with AD, which may enhance the vicious cycle of itching and scratching, resulting in aggravation of the skin eczema. These results provide new insights on the mechanism of acute stress-related exacerbation of itch in patients with AD.


Asunto(s)
Dermatitis Atópica/complicaciones , Prurito/psicología , Estrés Psicológico/complicaciones , Adulto , Estudios de Casos y Controles , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/psicología , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Prurito/diagnóstico , Prurito/etiología , Índice de Severidad de la Enfermedad , Estrés Psicológico/psicología , Brote de los Síntomas , Adulto Joven
6.
J Nutr Health Aging ; 23(1): 105-110, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30569078

RESUMEN

BACKGROUND: Globally there are several operational definitions for sarcopenia, complicating clinical and research applications. OBJECTIVE: The objective of the Australian and New Zealand Society for Sarcopenia and Frailty Research (ANZSSFR) Task Force on Diagnostic Criteria for Sarcopenia was to reach consensus on the operational definition of sarcopenia for regional use by clinicians and researchers. METHOD: A four-Phase modified Delphi process was undertaken in which 24 individuals with expertise or a recognised interest in sarcopenia from different fields across Australia and New Zealand were invited to be Task Force members. An initial face-to-face meeting was held in Adelaide, South Australia, in November 2017, followed by two subsequent online Phases conducted by electronic surveys. A final Phase was used to approve the final statements. Responses were analysed using a pre-specified strategy. The level of agreement required for consensus was 80%. RESULTS: In Phase 2, 94.1% of Task Force respondents voted in favour of adopting an existing operational definition of sarcopenia. In Phase 3, 94.4% of respondents voted in favour of adopting the European Working Group on Sarcopenia in Older People (EWGSOP) definition as the operational definition for sarcopenia in Australia and New Zealand. CONCLUSION: With consensus achieved, the ANZSSFR will adopt, promote and validate the EWGSOP operational definition of sarcopenia for use by clinicians and researchers in Australia and New Zealand.


Asunto(s)
Sarcopenia/diagnóstico , Anciano , Anciano de 80 o más Años , Australia , Consenso , Femenino , Humanos , Masculino , Nueva Zelanda , Encuestas y Cuestionarios
7.
Osteoporos Int ; 29(8): 1747-1757, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29947869

RESUMEN

The present study, drawn from a sample of the Icelandic population, quantified high immediate risk and utility loss of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) that attenuated with time. INTRODUCTION: The risk of a subsequent osteoporotic fracture is particularly acute immediately after an index fracture and wanes progressively with time. The aim of this study was to quantify the risk and utility consequences of subsequent fracture after a sentinel fracture (at the hip, spine, distal forearm and humerus) with an emphasis on the time course of recurrent fracture. METHODS: The Reykjavik Study fracture registration, drawn from a sample of the Icelandic population (n = 18,872), recorded all fractures of the participants from their entry into the study until December 31, 2012. Medical records for the participants were manually examined and verified. First sentinel fractures were identified. Subsequent fractures, deaths, 10-year probability of fracture and cumulative disutility using multipliers derived from the International Costs and Utilities Related to Osteoporotic fractures Study (ICUROS) were examined as a function of time after fracture, age and sex. RESULTS: Over 10 years, subsequent fractures were sustained in 28% of 1498 individuals with a sentinel hip fracture. For other sentinel fractures, the proportion ranged from 35 to 38%. After each sentinel fracture, the risk of subsequent fracture was highest in the immediate post fracture interval and decreased markedly with time. Thus, amongst individuals who sustained a recurrent fracture, 31-45% did so within 1 year of the sentinel fracture. Hazard ratios for fracture recurrence (population relative risks) were accordingly highest immediately after the sentinel fracture (2.6-5.3, depending on the site of fracture) and fell progressively over 10 years (1.5-2.2). Population relative risks also decreased progressively with age. The utility loss during the first 10 years after a sentinel fracture varied by age (less with age) and sex (greater in women). In women at the age of 70 years, the mean utility loss due to fractures in the whole cohort was 0.081 whereas this was 12-fold greater in women with a sentinel hip fracture, and was increased 15-fold for spine fracture, 4-fold for forearm fracture and 8-fold for humeral fracture. CONCLUSION: High fracture risks and utility loss immediately after fracture suggest that treatment given as soon as possible after fracture would avoid a higher number of new fractures compared with treatment given later. This provides the rationale for very early intervention immediately after a sentinel fracture.


Asunto(s)
Fracturas Osteoporóticas/epidemiología , Adulto , Distribución por Edad , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Traumatismos del Antebrazo/epidemiología , Fracturas de Cadera/epidemiología , Humanos , Fracturas del Húmero/epidemiología , Islandia/epidemiología , Masculino , Persona de Mediana Edad , Recurrencia , Sistema de Registros , Medición de Riesgo/métodos , Distribución por Sexo , Fracturas de la Columna Vertebral/epidemiología , Factores de Tiempo
8.
Osteoporos Int ; 29(3): 557-566, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29230511

RESUMEN

This study used data from the International Costs and Utilities Related to Osteoporotic fractures Study (ICUROS) to estimate the quality of life (QoL) impact of fracture. Hip, vertebral, and distal forearm fractures incur substantial QoL losses. Hip and vertebral fracture results in markedly impaired QoL for at least 18 months. INTRODUCTION: The International Costs and Utilities Related to Osteoporotic fractures Study (ICUROS) is a multinational observational study that aims to describe costs and quality of life (QoL) consequences of osteoporotic fractures. To date, 11 countries have participated in the study: Australia, Austria, Estonia, France, Italy, Lithuania, Mexico, Russia, Spain, the UK, and the USA. The objective of this paper is to describe the QoL impact of hip, vertebral, and distal forearm fracture. METHODS: Data were collected at four time-points for five QoL point estimates: within 2 weeks after fracture (including pre-fracture recall) and at 4, 12, and 18 months after fracture. Quality of life was measured as health state utility values (HSUVs) derived from the EQ-5D-3L. Complete case analysis was conducted as the base case with available case and multiple imputation performed as sensitivity analyses. Multivariate analysis was performed to explore predictors of QoL impact of fracture. RESULTS: Among 5456 patients enrolled using convenience sampling, 3021 patients were eligible for the base case analysis (1415 hip, 1047 distal forearm, and 559 vertebral fractures). The mean (SD) difference between HSUV before and after fracture for hip, vertebral, and distal forearm fracture was estimated at 0.89 (0.40), 0.67 (0.45), and 0.48 (0.34), respectively (p < 0.001 for all fracture types). Eighteen months after fracture, mean HSUVs were lower than before the fracture in patients with hip fracture (0.66 vs. 0.77 p < 0.001) and vertebral fracture (0.70 vs. 0.83 p < 0.001). Hospitalization and higher recalled pre-fracture QoL were associated with increased QoL impact for all fracture types. CONCLUSIONS: Hip, vertebral, and distal forearm fractures incur substantial loss in QoL and for patients with hip or vertebral fracture, QoL is markedly impaired for at least 18 months.


Asunto(s)
Fracturas Osteoporóticas/rehabilitación , Calidad de Vida , Anciano , Anciano de 80 o más Años , Femenino , Traumatismos del Antebrazo/rehabilitación , Fracturas de Cadera/rehabilitación , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Recurrencia , Factores Socioeconómicos , Fracturas de la Columna Vertebral/rehabilitación
9.
Osteoporos Int ; 28(10): 3005-3015, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28725985

RESUMEN

Falls among the elderly are common and characteristics may differ between injurious and non-injurious falls. Among 887 older Australian women followed for 1.6 years, 32% fell annually. Only 8.5% resulted in fracture and/or hospital admission. The characteristics of those falls are indistinguishable from those not coming to medical attention. INTRODUCTION: The precipitants and environment of all falls occurring among a large cohort of older Caucasian women were categorised by injury status to determine if the characteristics differed between injurious and non-injurious falls. METHODS: Among 887 Australian women (70+ years), falls were ascertained using monthly postcard calendars and a questionnaire was administered for each fall. Hospital admissions and fractures were independently confirmed. RESULTS: All falls were reported for a mean observation time of 577 (IQR 546-607) days per participant, equating to a total 1400 person-years. Thirty-two percent fell at least once per year. The most common features of a fall were that the faller was walking (61%) at home (61%) during the day (88%) and lost balance (32%). Only 12% of all falls occurred at night. Despite no difference in the type of injury between day and night, the likelihood of being hospitalised from a fall at night was 4.5 times greater than that of a daytime fall with adjustment for injury type and participant age (OR 4.5, 95% CI 2.1, 9.5; p < 0.001). Of all falls, approximately one third were associated with no injury to the faller (31%), one third reported a single injury (37%) and one third reported more than one injury (32%). In 95% of falls, the faller was not admitted to hospital. Only 5% of falls resulted in fracture(s). CONCLUSIONS: Our findings demonstrate the significant diversity of precipitants and environment where falls commonly occur among older community-dwelling women. Falls resulting in fracture and/or hospital admission collectively represent 8.5% of all falls and their characteristics are indistinguishable from falls not coming to medical attention and incurring no apparent cost to the health system.


Asunto(s)
Accidentes por Caídas/prevención & control , Heridas y Lesiones/etiología , Accidentes por Caídas/estadística & datos numéricos , Accidentes Domésticos/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Ambiente , Femenino , Estudios de Seguimiento , Fracturas Óseas/epidemiología , Fracturas Óseas/etiología , Fracturas Óseas/terapia , Hospitalización/estadística & datos numéricos , Humanos , Vida Independiente/lesiones , Vida Independiente/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Prevalencia , Factores de Riesgo , Victoria/epidemiología , Heridas y Lesiones/epidemiología , Heridas y Lesiones/terapia
10.
J Nutr Health Aging ; 21(2): 147-151, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28112768

RESUMEN

OBJECTIVE: This study aimed to examine the association between baseline and changes in dietary quality assessed by the Alternative Healthy Eating Index-2010 (AHEI-2010) and abdominal aortic calcification (AAC) among community-dwelling older adults. DESIGN: Population-based longitudinal study. SETTING: A subset of the Melbourne Collaborative Cohort Study (MCCS). PARTICIPANTS: 262 community-dwelling adults (60% female) aged 53 ± 5 years at baseline. MEASUREMENTS: Dietary intake was assessed using validated Food Frequency Questionnaires at baseline (1990-1994) and follow-up (2010-2011). AAC was evaluated by radiography and dual-energy x-ray absorptiometry (DXA) at follow-up. RESULTS: Higher baseline AHEI-2010 score was associated with lower AAC severity by radiography [OR (95% CI) for Tertile 3 VS Tertile 1: 0.53 (0.29-0.99)] after adjustment for gender, age, physical activity, smoking, BMI, systolic blood pressure, plasma total cholesterol, calcium and energy intake. The association between AHEI-2010 and AAC severity by DXA was also significant in the multivariate-adjusted model [OR (95% CI) for Tertile 3 VS Tertile 1: 0.38 (0.20-0.70)]. Changes in AHEI-2010 over 18 years were not associated with AAC severity. CONCLUSION: Baseline but not the changes in AHEI-2010 was inversely associated with the risk of AAC severity suggesting that a high quality diet might help prevent or delay the progression of AAC in community-dwelling older adults and the benefits might be manifested over the long-term.


Asunto(s)
Estenosis de la Válvula Aórtica/epidemiología , Válvula Aórtica/patología , Calcinosis/epidemiología , Dieta , Absorciometría de Fotón , Presión Sanguínea , Índice de Masa Corporal , Calcio/sangre , Colesterol/sangre , Estudios de Cohortes , Progresión de la Enfermedad , Ingestión de Energía , Ejercicio Físico , Femenino , Estudios de Seguimiento , Humanos , Vida Independiente , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Evaluación Nutricional , Encuestas y Cuestionarios
11.
J Physiol ; 595(6): 2021-2041, 2017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28054347

RESUMEN

KEY POINTS: The internal anal sphincter develops tone important for maintaining high anal pressure and continence. Controversy exists regarding the mechanisms underlying tone development. We examined the hypothesis that tone depends upon electrical slow waves (SWs) initiated in intramuscular interstitial cells of Cajal (ICC-IM) by activation of Ca2+ -activated Cl- channels (ANO1, encoded by Ano1) and voltage-dependent L-type Ca2+ channels (CavL , encoded by Cacna1c). Measurement of membrane potential and contraction indicated that ANO1 and CavL have a central role in SW generation, phasic contractions and tone, independent of stretch. ANO1 expression was examined in wildtype and Ano1/+egfp mice with immunohistochemical techniques. Ano1 and Cacna1c expression levels were examined by quantitative PCR in fluorescence-activated cell sorting. ICC-IM were the predominant cell type expressing ANO1 and the most likely candidate for SW generation. SWs in ICC-IM are proposed to conduct to smooth muscle where Ca2+ entry via CavL results in phasic activity that sums to produce tone. ABSTRACT: The mechanism underlying tone generation in the internal anal sphincter (IAS) is controversial. We examined the hypothesis that tone depends upon generation of electrical slow waves (SWs) initiated in intramuscular interstitial cells of Cajal (ICC-IM) by activation of Ca2+ -activated Cl- channels (encoded by Ano1) and voltage-dependent L-type Ca2+ channels (encoded by Cacna1c). Phasic contractions and tone in the IAS were nearly abolished by ANO1 and CavL antagonists. ANO1 antagonists also abolished SWs as well as transient depolarizations that persisted after addition of CavL antagonists. Tone development in the IAS did not require stretch of muscles, and the sensitivity of contraction to ANO1 antagonists was the same in stretched versus un-stretched muscles. ANO1 expression was examined in wildtype and Ano1/+egfp mice with immunohistochemical techniques. Dual labelling revealed that ANO1 expression could be resolved in ICC but not smooth muscle cells (SMCs) in the IAS and rectum. Ano1, Cacna1c and Kit gene expression were the same in extracts of IAS and rectum muscles. In IAS cells isolated with fluorescence-activated cell sorting, Ano1 expression was 26.5-fold greater in ICC than in SMCs while Cacna1c expression was only 2-fold greater in SMCs than in ICC. These data support a central role for ANO1 and CavL in the generation of SWs and tone in the IAS. ICC-IM are the probable cellular candidate for ANO1 currents and SW generation. We propose that ANO1 and CavL collaborate to generate SWs in ICC-IM followed by conduction to adjacent SMCs where phasic calcium entry through CavL sums to produce tone.


Asunto(s)
Canal Anal/fisiología , Canales de Calcio Tipo L/fisiología , Canales de Cloruro/fisiología , Células Intersticiales de Cajal/fisiología , Canal Anal/metabolismo , Animales , Anoctamina-1 , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Canales de Cloruro/genética , Canales de Cloruro/metabolismo , Femenino , Expresión Génica , Técnicas In Vitro , Células Intersticiales de Cajal/metabolismo , Masculino , Potenciales de la Membrana , Ratones Endogámicos C57BL , Ratones Transgénicos , Contracción Muscular , Músculo Liso/metabolismo , Músculo Liso/fisiología , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Proteínas Proto-Oncogénicas c-kit/fisiología
12.
Osteoporos Int ; 27(3): 905-913, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26438309

RESUMEN

SUMMARY: Non-hip, non-vertebral fractures (NHNVF) were compared with hip, vertebral and controls. NHNVF were younger and heavier than controls and hip/vertebral fractures in both men and women, respectively. Falls and prior fractures were less common in NHNVF than hip fractures. Glucocorticoid use was lower in NHNVF compared to vertebral fracture (VF) in men. INTRODUCTION: Although hip fracture (HF) and vertebral fractures (VF) receive the most attention in the literature and are the targeted sites for fracture prevention, non-hip, non-vertebral fracture (NHNVF) sites account for a greater proportion of fractures than the hip or vertebrae. This study aimed to assess risk factors for NHNVF and compare them with those for HF, VF and controls. METHODS: Incident fractures during 2005-2007 for men and 1994-1996 for women were identified using computerised keyword searches of radiological reports, and controls were selected at random from electoral rolls for participation in the Geelong Osteoporosis Study. Participants aged 60+ years were included in this study. RESULTS: Compared to controls, men and women with NHNVF were younger (ORs, 0.90, 95% CI 0.86-0.94; and 0.96, 0.93-0.98, respectively) and had a lower femoral neck bone mineral density (BMD) T-score (age-adjusted; difference [men] 0.383, P = 0.002; [women] 0.287, P = 0.001). Compared to HF, men and women with NHNVF were heavier (difference [men] 9.0 kg, P = 0.01; [women] 7.6 kg, P < 0.001). Heavier weight was also a risk factor for women with NHNVF compared to VF (1.03, 1.01-1.06). In men with NHNVF, falls (0.37, 0.14-0.97) and prior fractures (0.38, 0.15-0.98) were less common compared to HF; and glucocorticoid use was less common for NHNVF (0.30, 0.11-0.85) compared to VF. CONCLUSIONS: Given the high numbers of NHNVF sustained by men and women in this study, fracture prevention strategies should focus on individuals with high risk of sustaining these types of fractures, as well as on individuals who are more likely to sustain a HF or VF.


Asunto(s)
Fracturas Osteoporóticas/etiología , Accidentes por Caídas/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Peso Corporal/fisiología , Densidad Ósea/fisiología , Estudios de Casos y Controles , Femenino , Cuello Femoral/fisiopatología , Glucocorticoides/efectos adversos , Fracturas de Cadera/epidemiología , Fracturas de Cadera/etiología , Fracturas de Cadera/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/fisiopatología , Factores de Riesgo , Factores Sexuales , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Fracturas de la Columna Vertebral/fisiopatología , Victoria/epidemiología
13.
Cell Death Dis ; 6: e2011, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26633717

RESUMEN

Serum response factor (SRF) is a transcription factor known to mediate phenotypic plasticity in smooth muscle cells (SMCs). Despite the critical role of this protein in mediating intestinal injury response, little is known about the mechanism through which SRF alters SMC behavior. Here, we provide compelling evidence for the involvement of SRF-dependent microRNAs (miRNAs) in the regulation of SMC apoptosis. We generated SMC-restricted Srf inducible knockout (KO) mice and observed both severe degeneration of SMCs and a significant decrease in the expression of apoptosis-associated miRNAs. The absence of these miRNAs was associated with overexpression of apoptotic proteins, and we observed a high level of SMC death and myopathy in the intestinal muscle layers. These data provide a compelling new model that implicates SMC degeneration via anti-apoptotic miRNA deficiency caused by lack of SRF in gastrointestinal motility disorders.


Asunto(s)
Mucosa Intestinal/metabolismo , MicroARNs/metabolismo , Factor de Respuesta Sérica/metabolismo , Animales , Apoptosis , Diferenciación Celular , Proliferación Celular , Humanos , Intestinos/citología , Intestinos/patología , Ratones , Miocitos del Músculo Liso , Transducción de Señal
14.
J Musculoskelet Neuronal Interact ; 15(4): 350-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26636281

RESUMEN

OBJECTIVES: To determine associations of inter- and intra-muscular adipose tissue (IMAT) with cardiometabolic health and physical function in older adults. METHODS: 48 community-dwelling older adults aged ⋝65 years (mean 71.6±4.8 years; 52% women) underwent whole-body dual-energy X-ray absorptiometry, to assess appendicular lean mass (ALM), and peripheral quantitative computed tomography (pQCT; 66% tibia), to assess calf IMAT cross-sectional area ([CSA]; cm2) and muscle density (mg/cm(3); higher values indicate lower fat infiltration). Fasting glucose, lipids, triglycerides and C-reactive protein (CRP) were analysed. Physical function was assessed by postural sway (computerised posturography; N=41), and gait analysis (GAITRite Electronic Walkway; N=40). RESULTS: Higher IMAT CSA and muscle density were associated with significantly higher (B=0.85 95%CI [0.34, 1.36]) and lower (-2.14 [-4.20, -0.08]) CRP and higher (0.93 [0.56, 1.30]) and lower postural sway (-3.12 [-4.74, -1.50]), respectively, after adjustment for age, sex and ALM/BMI. Higher IMAT CSA was associated with slower gait speed and cadence, and greater step time and step width (all P<0.03), while higher muscle density was associated with smaller step width (P<0.01) only. CONCLUSIONS: Older adults with higher calf IMAT have poorer balance, mobility and inflammatory status. Interventions aimed at improving physical function in older adults should incorporate strategies to reduce IMAT.


Asunto(s)
Tejido Adiposo/patología , Envejecimiento/patología , Composición Corporal/fisiología , Músculo Esquelético/patología , Aptitud Física/fisiología , Sarcopenia/patología , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Pierna , Masculino
15.
Osteoporos Int ; 26(6): 1781-90, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25792491

RESUMEN

UNLABELLED: We investigated change in health-related quality of life due to fracture in Australian adults aged over 50 years. Fractures reduce quality of life with the loss sustained at least over 12 months. At a population level, the loss was equivalent to 65 days in full health per fracture. PURPOSE: We aimed to quantify the change in health-related quality of life (HRQoL) that occurred as a consequence of a fracture using the EQ-5D-3 L questionnaire. METHODS: Adults aged ≥50 years with a low to moderate energy fracture were recruited from eight study centres across Australia. This prospective study included an 18-month follow-up of participants recruited within 2 weeks of a fracture (hip, wrist, humerus, vertebral and ankle). Information collected at baseline and 4, 12 and 18 months included characteristics of participants such as income level, education and prior fracture status. At 12 months post-fracture, the cumulative loss of quality of life was estimated using multivariate regression analysis to identify the predictors of HRQoL loss. RESULTS: Mean HRQoL for all participants before fracture was 0.86, with wrist fracture having the highest pre-fracture HRQoL (0.90), while vertebral fracture had the lowest (0.80). HRQoL declined to 0.42 in the immediate post-fracture period. Only participants with a wrist, humerus or ankle fracture returned to their pre-fracture HRQoL after 18 months. An increased loss of HRQoL over 12 months was associated with HRQoL prior to the fracture, hospitalisation, education and fracture site. The multiple regression explained 30 % of the variation in the cumulative HRQoL loss at 12 months post-fracture for all fractures. CONCLUSION: Low to moderate energy fractures reduce HRQoL, and this loss is sustained for at least 12 months or, in the case of hip and spine fractures, at least 18 months. At a population level, this represents an average loss of 65 days in full health per fragility fracture. This significant burden reinforces the need for cost-effective fracture prevention strategies.


Asunto(s)
Fracturas Osteoporóticas/rehabilitación , Calidad de Vida , Anciano , Anciano de 80 o más Años , Australia , Costo de Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Años de Vida Ajustados por Calidad de Vida , Factores Socioeconómicos
17.
Am J Physiol Gastrointest Liver Physiol ; 307(11): G1057-72, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25301187

RESUMEN

The effector cells and second messengers participating in nitrergic neuromuscular transmission (NMT) were investigated in the mouse internal anal sphincter (IAS). Protein expression of guanylate cyclase (GCα, GCß) and cyclic GMP-dependent protein kinase I (cGKI) were examined in cryostat sections with dual-labeling immunohistochemical techniques in PDGFRα(+) cells, interstitial cells of Cajal (ICC), and smooth muscle cells (SMC). Gene expression levels were determined with quantitative PCR of dispersed cells from Pdgfrα(egfp/+), Kit(copGFP/+), and smMHC(Cre-egfp) mice sorted with FACS. The relative gene and protein expression levels of GCα and GCß were PDGFRα(+) cells > ICC ≫ SMC. In contrast, cGKI gene expression sequence was SMC = ICC > PDGFRα(+) cells whereas cGKI protein expression sequence was neurons > SMC ≫ ICC = PDGFRα(+) cells. The functional role of cGKI was investigated in cGKI(-/-) mice. Relaxation with 8-bromo (8-Br)-cGMP was greatly reduced in cGKI(-/-) mice whereas responses to sodium nitroprusside (SNP) were partially reduced and forskolin responses were unchanged. A nitrergic relaxation occurred with nerve stimulation (NS, 5 Hz, 60 s) in cGKI(+/+) and cGKI(-/-) mice although there was a small reduction in the cGKI(-/-) mouse. N(ω)-nitro-l-arginine (l-NNA) abolished responses during the first 20-30 s of NS in both animals. The GC inhibitor ODQ greatly reduced or abolished SNP and nitrergic NS responses in both animals. These data confirm an essential role for GC in NO-induced relaxation in the IAS. However, the expression of GC and cGKI by all three cell types suggests that each may participate in coordinating muscular responses to NO. The persistence of nitrergic NMT in the cGKI(-/-) mouse suggests the presence of a significant GC-dependent, cGKI-independent pathway.


Asunto(s)
Canal Anal/fisiología , Unión Neuromuscular/fisiología , Óxido Nítrico/fisiología , Transmisión Sináptica/fisiología , Canal Anal/inervación , Animales , Aorta Torácica/metabolismo , Proteína Quinasa Dependiente de GMP Cíclico Tipo I/genética , Proteína Quinasa Dependiente de GMP Cíclico Tipo I/fisiología , Guanilato Ciclasa/metabolismo , Técnicas In Vitro , Ratones , Ratones Noqueados , Contracción Muscular/efectos de los fármacos , Sistemas de Mensajero Secundario/efectos de los fármacos , Sistemas de Mensajero Secundario/fisiología
18.
Neurogastroenterol Motil ; 26(4): 556-70, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24460867

RESUMEN

BACKGROUND: 5-Hydroxytryptamine (5-HT, serotonin) is an important regulator of colonic motility and secretion; yet the role of serotonergic neurons in the colon is controversial. METHODS: We used immunohistochemical techniques to examine their projections throughout the enteric nervous system and interstitial cells of Cajal (ICC) networks in the murine proximal to mid colon. KEY RESULTS: Serotonergic neurons, which were mainly calbindin positive, occurred only in myenteric ganglia (1 per 3 ganglia). They were larger than nNOS neurons but similar in size to Dogiel Type II (AH) neurons. 5-HT neurons, appeared to make numerous varicose contacts with each other, most nNOS neurons, Dogiel Type II/AH neurons and glial cells. 5-HT, calbindin and nNOS nerve fibers also formed a thin perimuscular nerve plexus that was associated with ganglia, which contained both nNOS positive and negative neurons, which lay directly upon the submucosal pacemaker ICC network. Neurons in perimuscular ganglia were surrounded by 5-HT varicosities. Submucous ganglia contained nNOS positive and negative neurons, and calbindin positive neurons, which also appeared richly supplied by serotonergic nerve varicosities. Serotonergic nerve fibers ran along submucosal arterioles, but not veins. Varicosities of serotonergic nerve fibers were closely associated with pacemaker ICC networks and with intramuscular ICC (ICC-IM). 5-HT2B receptors were found on a subpopulation of non-5-HT containing myenteric neurons and their varicosities, pacemaker ICC-MY and ICC-IM. CONCLUSIONS & INFERENCES: Myenteric serotonergic neurons, whose axons exhibit considerable divergence, regulate the entire enteric nervous system and are important in coordinating motility with secretion. They are not just interneurons, as regularly assumed, but possibly also motor neurons to ICC and blood vessels, and some may even be sensory neurons.


Asunto(s)
Colon/inervación , Plexo Mientérico/citología , Neuronas Serotoninérgicas/citología , Animales , Colon/metabolismo , Células Intersticiales de Cajal/citología , Masculino , Ratones , Ratones Endogámicos C57BL , Receptor de Serotonina 5-HT2B/metabolismo
19.
Osteoporos Int ; 25(1): 187-93, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23800748

RESUMEN

UNLABELLED: Sarcopenia may be diagnosed in the clinic using operational definitions based on low muscle mass or function. This prospective, population-based study revealed that sex-specific associations may exist between operational definitions of sarcopenia and falls in community-dwelling middle-aged and older adults. INTRODUCTION: The objective of this study is to verify associations between sarcopenia and falls risk and to determine changes in sarcopenia prevalence over 5 years in middle-aged and older men and women according to different anthropometric and performance-based operational definitions. METHODS: N = 681 volunteers (48% female; mean ± SD age 61.4 ± 7.0 years) participated in baseline and follow-up assessments (mean 5.1 ± 0.5 years later). Appendicular lean mass (ALM) was assessed by dual-energy X-ray absorptiometry, hand grip (HGS) and lower-limb (LLS) strength were assessed by dynamometry, and falls risk was determined using the physiological profile assessment. Anthropometric definitions (ALM/height squared [ALM-H], ALM/weight × 100 and a residuals method [ALM-R]) and performance-based definitions (HGS, LLS and upper- and lower-limb muscle quality [LMQ]) of sarcopenia were examined. The lowest 20% of the sex-specific distribution for each definition at baseline was classified as sarcopenia. RESULTS: Sarcopenia prevalence increased after 5 years for all operational definitions except ALM-H (men: -4.0%; women: -5.5%). Men classified with sarcopenia according to anthropometric definitions, and women classified with sarcopenia according to performance-based definitions, had significant increases in falls risk over 5 years (all P < 0.05) compared to individuals without sarcopenia. Significant sex interactions were observed for ALM-R, LLS and LMQ (all P < 0.05) definitions. CONCLUSIONS: Sarcopenia prevalence generally increases at a higher rate when assessed using performance-based definitions. Sarcopenia is associated with increases in falls risk over 5 years in community-dwelling middle-aged and older adults, but sex-specific differences may exist according to different anthropometric or performance-based definitions.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Sarcopenia/diagnóstico , Anciano , Antropometría/métodos , Composición Corporal/fisiología , Femenino , Fuerza de la Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad , Fuerza Muscular/fisiología , Músculo Esquelético/fisiopatología , Prevalencia , Estudios Prospectivos , Características de la Residencia , Factores de Riesgo , Sarcopenia/complicaciones , Sarcopenia/epidemiología , Sarcopenia/fisiopatología , Factores Sexuales , Tasmania/epidemiología
20.
Neurogastroenterol Motil ; 25(9): e609-20, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23809506

RESUMEN

BACKGROUND: Purinergic signaling provides regulation of colonic motility. Smooth muscle cells (SMC), interstitial cells of Cajal (ICC), and platelet-derived growth factor receptor α-positive (PDGFRα(+) ) cells are electrically coupled and form a functional (SIP) syncytium that constitutes the receptive field for motor neurotransmitters in the tunica muscularis. Each cell type in the SIP syncytium has specialized functions in mediating motor neurotransmission. We compared gene transcripts for purinergic receptors and membrane-bound enzymes for purine degradation expressed by each cell type of the SIP syncytium. METHODS: Fluorescence-activated cell sorting (FACS) was used to purify SMC, ICC, and PDGFRα(+) cells from mixed cell populations of colonic muscles dispersed from reporter strains of mice with constitutive expression of green fluorescent proteins. Differential expression of functional groups of genes related to purinergic signaling was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). KEY RESULTS: We detected marked phenotypic differences among SMC, ICC, and PDGFRα(+) cells. Substantial numbers of genes of importance in purinergic neurotransmission were enriched in PDGFRα(+) cells in relation to SMC and ICC. Notably, genes related to mediating effects and extracellular biotransformation of enteric purinergic inhibitory neurotransmitters were strongly expressed by PDGFRα(+) cells. CONCLUSIONS & INFERENCES: Our results demonstrate differential expression of genes for proteins involved in purinergic signaling in the SIP syncytium. These results may further clarify the specific functions of each cell type, identify novel biomarkers for postjunctional cells, and provide hypotheses for further studies to understand the physiological roles of cells of the SIP syncytium.


Asunto(s)
Motilidad Gastrointestinal/genética , Células Intersticiales de Cajal/metabolismo , Miocitos del Músculo Liso/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Transcriptoma , Animales , Colon/citología , Colon/metabolismo , Ratones , Ratones Transgénicos , Purinas , Receptores Purinérgicos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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