Individual and joint trajectories of change in bone, lean mass and physical performance in older men.

BackgroundDeclines in bone, muscle and physical performance are associated with adverse health outcomes in older adults. However, few studies have described concurrent age-related patterns of change in these factors. The purpose of this study was to characterize change in four properties of muscle, physical performance, and bone in a prospective cohort study of older men.MethodsUsing repeated longitudinal data from up to four visits across 6.9 years from up to 4681 men (mean age at baseline 72.7 yrs. ±5.3) participating in the Osteoporotic Fractures in Men (MrOS) Study, we used group-based trajectory models (PROC TRAJ in SAS) to identify age-related patterns of change in four properties of muscle, physical performance, and bone: total hip bone mineral (BMD) density (g/m2) and appendicular lean mass/ht2 (kg/m2), by DXA; grip strength (kg), by hand dynamometry; and walking speed (m/s), by usual walking pace over 6 m. We also described joint trajectories in all pair-wise combinations of these measures. Mean posterior probabilities of placement in each trajectory (or joint membership in latent groups) were used to assess internal reliability of the model. The number of trajectories for each individual factor was limited to three, to ensure that the pair-wise determination of joint trajectories would yield a tractable number of groups as well as model fit considerations.ResultsThe patterns of change identified were generally similar for all measures, with three district groups declining over time at roughly similar rates; joint trajectories revealed similar patterns with no cross-over or convergence between groups. Mean posterior probabilities for all trajectories were similar and consistently above 0.8 indicating reasonable model fit to the data.ConclusionsOur description of trajectories of change with age in bone mineral density, grip strength, walking speed and appendicular lean mass found that groups identified by these methods appeared to have little crossover or convergence of change with age, even when considering joint trajectories of change in these factors

Candidate gene analysis of femoral neck trabecular and cortical volumetric bone mineral density in older men.

In contrast to conventional dual-energy X-ray absorptiometry, quantitative computed tomography separately measures trabecular and cortical volumetric bone mineral density (vBMD). Little is known about the genetic variants associated with trabecular and cortical vBMD in humans, although both may be important for determining bone strength and osteoporotic risk. In the current analysis, we tested the hypothesis that there are genetic variants associated with trabecular and cortical vBMD at the femoral neck by genotyping 4608 tagging and potentially functional single-nucleotide polymorphisms (SNPs) in 383 bone metabolism candidate genes in 822 Caucasian men aged 65 years or older from the Osteoporotic Fractures in Men Study (MrOS). Promising SNP associations then were tested for replication in an additional 1155 men from the same study. We identified SNPs in five genes (IFNAR2, NFATC1, SMAD1, HOXA, and KLF10) that were robustly associated with cortical vBMD and SNPs in nine genes (APC, ATF2, BMP3, BMP7, FGF18, FLT1, TGFB3, THRB, and RUNX1) that were robustly associated with trabecular vBMD. There was no overlap between genes associated with cortical vBMD and trabecular vBMD. These findings identify novel genetic variants for cortical and trabecular vBMD and raise the possibility that some genetic loci may be unique for each bone compartment

Frailty and Risk of Falls, Fracture, and Mortality in Older Women: The Study of Osteoporotic Fractures

Background. A standard phenotype of frailty was associated with an increased risk of adverse outcomes including mortality in a recent study of older adults. However, the predictive validity of this phenotype for fracture outcomes and across risk subgroups is uncertain. Methods. To determine whether a standard frailty phenotype was independently associated with risk of adverse health outcomes in older women and to evaluate the consistency of associations across risk subgroups defined by age and body mass index (BMI), we ascertained frailty status in a cohort of 6724 women ≥ 69 years and followed them prospectively for incident falls, fractures, and mortality. Frailty was defined by the presence of three or more of the following criteria: unintentional weight loss, weakness, self-reported poor energy, slow walking speed, and low physical activity. Incident recurrent falls were defined as at least two falls during the subsequent year. Incident fractures (confirmed with x-ray reports), including hip fractures, and deaths were ascertained during an average of 9 years of follow-up. Results. After controlling for multiple confounders such as age, health status, medical conditions, functional status, depressive symptoms, cognitive function, and bone mineral density, frail women were subsequently at increased risk of recurrent falls (multivariate odds ratio = 1.38, 95% confidence interval [CI], 1.02-1.88), hip fracture (multivariate hazards ratio [MHR] = 1.40, 95% CI, 1.03-1.90), any nonspine fracture (MHR = 1.25, 95% CI, 1.05-1.49), and death (MHR = 1.82, 95% CI, 1.56-2.13). The associations between frailty and these outcomes persisted among women ≥ 80 years. In addition, associations between frailty and an increased risk of falls, fracture, and mortality were consistently observed across categories of BMI, including BMI ≥ 30 kg/m2. Conclusion. Frailty is an independent predictor of adverse health outcomes in older women, including very elderly women and older obese wome

A Post-Pneumonia Epizootic Evaluation of the Rapid City, South Dakota Bighorn Sheep Herd

Pneumonia is a major factor affecting populations of free-ranging bighorn sheep (Ovis canadensis) across western North America. Pneumonia can occur in large-scale epizootics, during which greater than half of the population typically dies. After these epizootics, surviving ewes continue to conceive and bear lambs. However, lamb recruitment may remain low due to periodic or annual pneumonia outbreaks causing high lamb mortality rates, sometimes greater than 90%. Our study focused on the Rapid City, South Dakota bighorn sheep (BHS) herd that has recorded pneumonia-induced population decline since 2009. The first objective was to improve lamb health and survival by identifying and removing individuals that chronically carry the pathogen (Mycoplasma ovipneumoniae [Movi]). A previous study that treated the Custer State Park, South Dakota BHS herd during 2016–2017 with the same techniques successfully eliminated chronic Movi carriers and increased lamb recruitment. We treated the Rapid City BHS herd from January 2018 to November 2020. We tested individual BHS for Movi upper respiratory infections using real-time polymerase chain reaction (RT-PCR) and exposure to Movi by a competitive enzyme-linked immunosorbent assay (ELISA). If individual sheep tested positive via RT-PCR for the presence of Movi twice consecutively it was considered a chronic carrier and was removed from the herd. We identified an intermittent carrier as testing positive and negative on different occasions and non-carriers as testing negative for every test. We identified patterns of Movi carriage using Movi testing data from 2016–2020 and deemed individuals as chronic, intermittent, or non-carriers. Over the course of the study, we removed four chronic and five intermittent carriers, and our results suggested that removing intermittent carriers may be necessary to reduce or eliminate Movi persistence in a BHS herd. We monitored the survival of lambs prior to and during carrier removal and our analysis indicated that carrier removal increased lamb survival up to six months in both sub-herds in the Rapid City BHS herd (Spring Creek survival prior to removal= 35.3% [95% CI 15.5%, 56.6%], Spring Creek Survival during removal= 75.5% [95% CI 51.4%, 91.3%]; Rapid Creek survival prior to removal= 8.54% [95% CI 0.45%, 27.4%], Rapid Creek survival during removal= 50.8% [95% CI 28.3%, 72.6%]). Subsequent field testing revealed that we removed all known chronic carriers from the herd and thereafter we documented no pneumonia-related mortalities supporting previous conclusions that carrier removal can increase lamb survival and health. The second objective was to quantify the body condition, diet quality, and diet composition of the ewes (14) in the Rapid City BHS herd post-pneumonia epizootic to better understand the current herd productivity to use as a baseline for future management. Further, we focused on how a ewe\u27s lactation status (i.e., lactating or not lactating) affected its digestive capabilities and diet selection. We collected data from March–August 2020. We used ultrasonography technology and body palpations to obtain body condition data and assessed diet quality and composition through percent fecal nitrogen and metabarcoding analyses, respectively. No significant relationships were found in the body condition and diet data collected. However, we identified that browse species were the primary forage consumed, making up 86.8% of lactating ewe samples and 58.3% of non-lactating ewe samples. This study represents the first attempt to understand the potential effects of nutritional condition post-pneumonia epizootic and provided an additional case study that illuminates diet composition differences between lactating and non-lactating ungulates

Is nutrition important to postpone frailty?

Purpose of review: The purpose of the present study is to provide an updated, systematic review of the recent literature on whether nutrition is important to postpone frailty. Recent findings: A systematic review of recent literature (past 12 months) identified nine studies (eight of which using a cross-sectional design) exploring the relationship between nutrition and frailty. A single randomized-controlled double-blind trial was published. However, being a pilot study, it was characterized by a relatively small sample size, short follow-up length (i.e., 6 months), and low statistical power. Notably, available evidence shows considerable variability in participants’ selection and assessment methods, rendering difficult direct comparisons. Size effects or magnitude of associations across the different studies cannot also be determined. Summary: There is a need for long-term, adequately powered, randomized controlled trials examining nutrition (alone or/and in combination with other appropriate interventions) as a means for postponing frailty in older persons

Selective serotonin reuptake inhibitors and selective serotonin and norepinephrine reuptake inhibitors use and risk of fractures in adults: a systematic review and meta-analysis

Objective: to evaluate the association between SSRI and SNRI use and risk of fractures in older adults. Methods: We systematically identified and analyzed observational studies comparing SSRI/SNRI use for depression with non-SSRI/SNRI use with a primary outcome of risk of fractures in older adults. We searched for studies in MEDLINE, PsycINFO, EMBASE, DARE, the Cochrane Library, Web of Science clinical trials research registers from 2011 for SSRIs and 1990 for SNRIs to November 29, 2016. Results: Thirty-three studies met our inclusion criteria, 23 studies were included in meta-analysis: 9 case-control studies and 14 cohort studies. A 1.67-fold increase in the risk of fracture for SSRI users compared to non-users was observed (Relative Risk 1.67, 95% CI 1.56-1.79, p=0.000). The risk of fracture increases with their long-term use: within 1 year the risk is 2.9% or one additional fracture in every 85 users; within 5 years the risk is 13.4% or one additional fracture in every 19 users. In meta-regression we found that the increase in risk did not differ across age groups (OR=1.006; p=0.173). A limited number of studies on SNRIs use and the risk of fractures prevented us from conducting a meta-analysis. Conclusions: Our systematic review showed an association between risk of fracture and the use of SSRIs, especially with increasing use. Age does not increase this risk. No such conclusions can be drawn about the effect of SNRIs on the risk of fracture due to a lack of studies

New velocity zones gain insights into the high velocity demands of soccer

Bakgrunn: Nøyaktige belastningsmålinger er en avgjørende faktor for å kunne optimalisere prestasjonsevne for fotballspillere. Med økende kampkravene på høye hastigheter, er de tradisjonelt brukte hastighetssonene mulig for vide til å nøyaktig beskrive belastning på høye hastigheter godt nok. Muligens begrenser dette presisjonen til å forstå kampkrav, og til å optimalisere treningen deretter. Derfor har denne studien som mål å sammenlikne posisjonspesifikke forskjeller fra kamp- til treningsbelastning i et nytt sett av mer presise hastighetssoner. Metode: 15 mannlige fotballspillere (77.7 ± 6.8 kg, 183.1 ± 6.6 cm) som spiller for en norsk eliteklubb, deltok i denne studien. GPS-data ble samlet inn fra trening og kamper i løpet av 2022. Denne studien delte den tradisjonelle høyhastighetssonen (HSR, 19.8 - 25.2km*t-1) i HSR-A (19.8-22.5km*t-1) og HSR-B (22.7-25.2 km*t-1). Videre, ble den tradisjonelle sonen spurting (SPR, >25.2km*t-1) delt inn i SPR-A (25.2-27.9 km*t-1), SPR-B (27.9-30.6 km*t-1) og SPR-C (>30.6 km*t-1). De målte variablene var distanse og antall innsatser i hastighetssonene. Resultat: Denne studien viste at spillere har gradvis mindre treningsbelastning med økende hastigheter, med ukentlig treningsbelastning gradvis synkende fra HSR-A (72%) til SPR-C (20%), sammenliknet med høyeste kampbelastning. Den gjennomsnittlige kampdistansen på HSR sone (605 ± 64m) ble fordelt i de nye HSR-A (67%) og HSR-B (33%). For kampdistanse på SPR sone (154 ± 25), ble dette inndelt i henholdsvis SPR-A (74%), SPR-B (22%) og SPR-C (4%), med større vekting på lavere hastigheter. Ved å sammenlikne trening med observert kampbelastning, viste dette at gjennomsnittspilleren løper respektivt 10 og 28% mindre HSR (p< .02) og SPR (p< .00) distanse i ukentlig treningsbelastning. Antall HSR innsatser i trening var liknende (p< .38) med kamp, mens SPR innstaser var 25% mindre (p< .01) i trening sammenliknet med kampbelastning. Konklusjon: Det å implementere nye hastighetssoner kan bidra til mer nøyaktig planlegging av høyhastighetsstrening, som kan bidra til å trene mot kampbelastning. Nøkkelord: Ekstern belastning – høyhastighet – spurting – posisjonsspesifikk - fotballBackground: Accurately monitoring load is a crucial part of optimizing physical performance for elite soccer players. With the trend of increased match loads at high velocities, the traditionally used zones may deploy to wide velocity thresholds, to accurately monitor load at high velocities. Subsequently, the aim of this study was comparing external running load in matches to weekly training load, for different playing positions, within a new set of more precise velocity zones. Methodology: Fifteen male soccer players (77.7 ± 6.8kg, 183.1 ± 6.6cm) playing for a Norwegian elite club, participated in this study. Global positioning system data were continuously collected during training and matches throughout the 2022 season. This study divided the traditional high-speed running (HSR, 19.8 - 25.2km*h-1) zone into HSR-A (19.8-22.5km*h-1) and HSR-B (22.7-25.2 km*h-1). Moreover, the traditional sprinting (SPR, >25.2km*h-1) zone was divided into SPR-A (25.2-27.9 km*h-1), SPR-B (27.9-30.6 km*h-1) and SPR-C (>30.6 km*h-1). Load variables were distances and efforts within the velocity zones. Results: This study showed that players have gradually decreasing training loads at higher velocities, with training distance gradually decreasing from HSR-A (72%) up to SPR-C (20%), when compared to the highest match load distance of the season. The average players HSR match distance (605 ± 64m) was distributed in the new zones HSR-A (67%) and HSR-B (33%). For the SPR match distance (154 ± 25), this was distributed in SPR-A (74%), SPR-B (22%) and SPR-C (4%), with a large portion of SPR load being within SPR-A zone. Further, comparisons between training and observed match loads, show that the average player covered respectively 10 and 28% less HSR (p< .02) and SPR (p< .00) distances in training. Efforts in training were similar at HSR (p< .38) and 25% less at SPR (p< .01) compared to matches. Conclusion: Implementing new velocity zones can enable more accurate planning of high velocity training in soccer, to prepare players according to match demands. Keywords: External Load – High velocity – Sprinting – Position-specific – Socce