Real-life results of balloon kyphoplasty for vertebral compression fractures from the SWISSspine registry

BACKGROUND CONTEXT The Swiss Federal Office of Public Health mandated a nationwide health technology assessment-registry for balloon kyphoplasty (BKP) for decision making on reimbursement of these interventions. The early results of the registry led to a permanent coverage of BKP by basic health insurance. The documentation was continued for further evidence generation. PURPOSE This analysis reports on the 1 year results of patients after BKP treatment. STUDY DESIGN Prospective multicenter observational case series. PATIENT SAMPLE The data on 625 cases with 819 treated vertebrae were documented from March 2005 to May 2012. OUTCOME MEASURES Surgeon-administered outcome instruments were primary intervention form for BKP and the follow-up form; patient self-reported measures were EuroQol-5D questionnaire, North American Spine Society outcome instrument /Core Outcome Measures Index (including visual analog scale), and a comorbidity questionnaire. Outcome measures were back pain, medication, quality of life (QoL), cement extrusions, and new fractures within the first postoperative year. METHODS Data were recorded preoperatively and at 3 to 6-month and 1-year follow-ups. Wilcoxon signed-rank test was used for comparison of pre- with postoperative measurements. Multivariate logistic regression was used to identify factors with a significant influence on the outcome. RESULTS Seventy percent of patients were women with mean age of 71 years (range, 18-91 years); mean age of men was 65 years (range, 15-93 years). Significant and clinically relevant reduction of back pain, improvement of QoL, and reduction of pain killer consumption was seen within the first postoperative year. Preoperative back pain decreased from 69.3 to 29.0 at 3 to 6-month and remained unchanged at 1-year follow-ups. Consequently, QoL improved from 0.23 to 0.71 and 0.75 at the same follow-up intervals. The overall vertebra-based cement extrusion rates with and without extrusions into intervertebral discs were 22.1% and 15.3%, respectively. Symptomatic cement extrusions with radiculopathy were five (0.8%). A new vertebral fracture within a year from the BKP surgery was observed in 18.4% of the patients. CONCLUSIONS The results of the largest observational study for BKP so far are consistent with published randomized trials and systematic reviews. In this routine health care setting, BKP is safe and effective in reducing pain, improving QoL, and lowering pain_killer consumption and has an acceptable rate of cement extrusions. Postoperative outcome results show clear and significant clinical improvement at early follow-up that remain stable during the first postoperative year.

Fixed and Flexible: Coexistence of Obligate and Facultative Migratory Strategies in a Freshwater Fish

Migration is an important event in many animal life histories, but the degree to which individual animals participate in seasonal migrations often varies within populations. The powerful ecological and evolutionary consequences of such partial migration are now well documented, but the underlying mechanisms are still heavily debated. One potential mechanism of partial migration is between-individual variation in body condition, where animals in poor condition cannot pay the costs of migration and hence adopt a resident strategy. However, underlying intrinsic traits may overrule such environmental influence, dictating individual consistency in migratory patterns. Unfortunately, field tests of individual consistency compared to the importance of individual condition on migratory propensity are rare. Here we analyse 6 years of field data on roach migration, gathered by tagging almost 3000 individual fish and monitoring their seasonal migrations over extended periods of time. Our aims were to provide a field test of the role of condition in wild fish for migratory decisions, and also to assess individual consistency in migratory tendency. Our analyses reveal that (1) migratory strategy, in terms of migration/residency, is highly consistent within individuals over time and (2) there is a positive relationship between condition and the probability of migration, but only in individuals that adopt a migratory strategy at some point during their lives. However, life-long residents do not differ in condition to migrants, hence body condition is only a good predictor of migratory tendency in fish with migratory phenotypes and not a more general determinant of migratory tendency for the population. As resident individuals can achieve very high body condition and still remain resident, we suggest that our data provides some of the first field evidence to show that both facultative and obligate strategies can co-exist within populations of migratory animals.

There and back again: migration in freshwater fishes

Animal migration is an amazing phenomenon that has fascinated humans for long. Many freshwater fishes also show remarkable migrations, whereof the spectacular mass migrations of salmonids from the spawning streams are the most well known and well studied. However, recent studies have shown that migration occurs in a range of freshwater fish taxa from many different habitats. In this review we focus on the causes and consequences of migration in freshwater fishes. We start with an introduction of concepts and categories of migration, and then address the evolutionary causes that drive individuals to make these migratory journeys. The basis for the decision of an individual fish to migrate or stay resident is an evaluation of the costs and benefits of different strategies to maximize its lifetime reproductive effort. We provide examples by discussing our own work on the causes behind seasonal migration in a cyprinid fish, roach (Rutilus rutilus (L., 1758)), within this framework. We then highlight different adaptations that allow fish to migrate over sometimes vast journeys across space, including capacity for orientation, osmoregulation, and efficient energy expenditure. Following this we consider the consequences of migration in freshwater fish from ecological, evolutionary, and conservation perspectives, and finally, we detail some of the recent developments in the methodologies used to collect data on fish migration and how these could be used in future research.

Interplay between temperature, fish partial migration and trophic dynamics

Whereas many studies have addressed the mechanisms driving partial migration, few have focused on the consequences of partial migration on trophic dynamics, and integrated studies combining the two approaches are virtually nonexistent. Here we show that temperature affects seasonal partial migration of cyprinid fish from lakes to predation refuges in streams during winter and that this migration in combination with temperature affects the characteristics and phenology of lower trophic levels in the lake ecosystem. Specifically, our six-year study showed that the proportion of fish migrating was positively related to lake temperature during the pre-migration growth period, i.e. during summer. Migration from the lake occurred later when autumn water temperatures were high, and timing of return migration to the lake occurred earlier at higher spring water temperatures. Moreover, the winter mean size of zooplankton in the lake increased with the proportion of fish being away from the lake, likely as a consequence of decreased predation pressure. Peak biomass of phytoplankton in spring occurred earlier at higher spring water temperatures and with less fish being away from the lake. Accordingly, peak zooplankton biomass occurred earlier at higher spring water temperature, but relatively later if less fish were away from the lake. Hence, the time between phyto- and zooplankton peaks depended only on the amount of fish being away from the lake, and not on temperature. The intensity of fish migration thereby had a major effect on plankton spring dynamics. These results significantly contribute to our understanding of the interplay between partial migration and trophic dynamics, and suggest that ongoing climate change may significantly affect such dynamics.

Temperature and Resource Availability May Interactively Affect Over-Wintering Success of Juvenile Fish in a Changing Climate

The predicted global warming may affect freshwater systems at several organizational levels, from organism to ecosystem. Specifically, in temperate regions, the projected increase of winter temperatures may have important effects on the over-winter biology of a range of organisms and especially for fish and other ectothermic animals. However, temperature effects on organisms may be directed strongly by resource availability. Here, we investigated whether over-winter loss of biomass and lipid content of juvenile roach (Rutilus rutilus) was affected by the physiologically relatively small (2-5°C) changes of winter temperatures predicted by the Intergovernmental Panel on Climate Change (IPCC), under both natural and experimental conditions. This was investigated in combination with the effects of food availability. Finally, we explored the potential for a correlation between lake temperature and resource levels for planktivorous fish, i.e., zooplankton biomass, during five consecutive winters in a south Swedish lake. We show that small increases in temperature (+2°C) affected fish biomass loss in both presence and absence of food, but negatively and positively respectively. Temperature alone explained only a minor part of the variation when food availability was not taken into account. In contrast to other studies, lipid analyses of experimental fish suggest that critical somatic condition rather than critical lipid content determined starvation induced mortality. Our results illustrate the importance of considering not only changes in temperature when predicting organism response to climate change but also food-web interactions, such as resource availability and predation. However, as exemplified by our finding that zooplankton over-winter biomass in the lake was not related to over-winter temperature, this may not be a straightforward task.

To boldly go: individual differences in boldness influence migratory tendency

Partial migration, whereby only a fraction of the population migrates, is thought to be the most common type of migration in the animal kingdom, and can have important ecological and evolutionary consequences. Despite this, the factors that influence which individuals migrate and which remain resident are poorly understood. Recent work has shown that consistent individual differences in personality traits in animals can be ecologically important, but field studies integrating personality traits with migratory behaviour are extremely rare. In this study, we investigate the influence of individual boldness, an important personality trait, upon the migratory propensity of roach, a freshwater fish, over two consecutive migration seasons. We assay and individually tag 460 roach and show that boldness influences migratory propensity, with bold individuals being more likely to migrate than shy fish. Our data suggest that an extremely widespread personality trait in animals can have significant ecological consequences via influencing individual-level migratory behaviour.

Sizing up your enemy: individual predation vulnerability predicts migratory probability

Partial migration, in which a fraction of a population migrate and the rest remain resident, occurs in an extensive range of species and can have powerful ecological consequences. The question of what drives differences in individual migratory tendency is a contentious one. It has been shown that the timing of partial migration is based upon a trade-off between seasonal fluctuations in predation risk and growth potential. Phenotypic variation in either individual predation risk or growth potential should thus mediate the strength of the trade-off and ultimately predict patterns of partial migration at the individual level (i.e. which individuals migrate and which remain resident). We provide cross-population empirical support for the importance of one component of this model—individual predation risk—in predicting partial migration in wild populations of bream Abramis brama, a freshwater fish. Smaller, high-risk individuals migrate with a higher probability than larger, low-risk individuals, and we suggest that predation risk maintains size-dependent partial migration in this system.

All eyes on me?! Social anxiety and self-directed perception of eye gaze

To date, only little is known about the self-directed perception and processing of subtle gaze cues in social anxiety that might however contribute to excessive feelings of being looked at by others. Using a web-based approach, participants (n=174) were asked whether or not briefly (300 ms) presented facial expressions modulated in gaze direction (0°, 2°, 4°, 6°, 8°) and valence (angry, fearful, happy, neutral) were directed at them. The results demonstrate a positive, linear relationship between self-reported social anxiety and stronger self-directed perception of others' gaze directions, particularly for negative (angry, fearful) and neutral expressions. Furthermore, faster responding was found for gaze more clearly directed at socially anxious individuals (0°, 2°, and 4°) suggesting a tendency to avoid direct gaze. In sum, the results illustrate an altered self-directed perception of subtle gaze cues. The possibly amplifying effects of social stress on biased self-directed perception of eye gaze are discussed.

Land use change and nitrogen feedbacks constrain the trajectory of the land carbon sink

Our understanding of Earth's carbon climate system depends critically upon interactions between rising atmospheric CO2, changing land use, and nitrogen limitation on vegetation growth. Using a global land model, we show how these factors interact locally to generate the global land carbon sink over the past 200 years. Nitrogen constraints were alleviated by N2 fixation in the tropics and by atmospheric nitrogen deposition in extratropical regions. Nonlinear interactions between land use change and land carbon and nitrogen cycling originated from three major mechanisms: (i) a sink foregone that would have occurred without land use conversion; (ii) an accelerated response of secondary vegetation to CO2 and nitrogen, and (iii) a compounded clearance loss from deforestation. Over time, these nonlinear effects have become increasingly important and reduce the present-day net carbon sink by ~40% or 0.4 PgC yr−1.

Effect of ticagrelor on the outcomes of patients with prior coronary artery bypass graft surgery: insights from the PLATelet inhibition and patient outcomes (PLATO) trial

BACKGROUND Patients with prior coronary artery bypass graft surgery (CABG) who present with an acute coronary syndrome have a high risk for recurrent events. Whether intensive antiplatelet therapy with ticagrelor might be beneficial compared with clopidogrel is unknown. In this substudy of the PLATO trial, we studied the effects of randomized treatment dependent on history of CABG. METHODS Patients participating in PLATO were classified according to whether they had undergone prior CABG. The trial's primary and secondary end points were compared using Cox proportional hazards regression. RESULTS Of the 18,613 study patients, 1,133 (6.1%) had prior CABG. Prior-CABG patients had more high-risk characteristics at study entry and a 2-fold increase in clinical events during follow-up, but less major bleeding. The primary end point (composite of cardiovascular death, myocardial infarction, and stroke) was reduced to a similar extent by ticagrelor among patients with (19.6% vs 21.4%; adjusted hazard ratio [HR], 0.91 [0.67, 1.24]) and without (9.2% vs 11.0%; adjusted HR, 0.86 [0.77, 0.96]; P(interaction) = .73) prior CABG. Major bleeding was similar with ticagrelor versus clopidogrel among patients with (8.1% vs 8.7%; adjusted HR, 0.89 [0.55, 1.47]) and without (11.8% vs 11.4%; HR, 1.08 [0.98, 1.20]; P(interaction) = .46) prior CABG. CONCLUSIONS Prior-CABG patients presenting with acute coronary syndrome are a high-risk cohort for death and recurrent cardiovascular events but have a lower risk for major bleeding. Similar to the results in no-prior-CABG patients, ticagrelor was associated with a reduction in ischemic events without an increase in major bleeding.

Lung cancer screening with CT: evaluation of radiologists and different computer assisted detection software (CAD) as first and second readers for lung nodule detection at different dose levels

OBJECTIVES To find the best pairing of first and second reader at highest sensitivity for detecting lung nodules with CT at various dose levels. MATERIALS AND METHODS An anthropomorphic lung phantom and artificial lung nodules were used to simulate screening CT-examination at standard dose (100 mAs, 120 kVp) and 8 different low dose levels, using 120, 100 and 80 kVp combined with 100, 50 and 25 mAs. At each dose level 40 phantoms were randomly filled with 75 solid and 25 ground glass nodules (5-12 mm). Two radiologists and 3 different computer aided detection softwares (CAD) were paired to find the highest sensitivity. RESULTS Sensitivities at standard dose were 92%, 90%, 84%, 79% and 73% for reader 1, 2, CAD1, CAD2, CAD3, respectively. Combined sensitivity for human readers 1 and 2 improved to 97%, (p1=0.063, p2=0.016). Highest sensitivities--between 97% and 99.0%--were achieved by combining any radiologist with any CAD at any dose level. Combining any two CADs, sensitivities between 85% and 88% were significantly lower than for radiologists combined with CAD (p<0.03). CONCLUSIONS Combination of a human observer with any of the tested CAD systems provide optimal sensitivity for lung nodule detection even at reduced dose at 25 mAs/80 kVp.