Summary Background Death within 90 days after total hip replacement is rare but might be avoidable dependent on patient and treatment factors. We assessed whether a secular decrease in death caused ...by hip replacement has occurred in England and Wales and whether modifiable perioperative factors exist that could reduce deaths. Methods We took data about hip replacements done in England and Wales between April, 2003, and December, 2011, from the National Joint Registry for England and Wales. Patient identifiers were used to link these data to the national mortality database and the Hospital Episode Statistics database to obtain details of death, sociodemographics, and comorbidity. We assessed mortality within 90 days of operation by Kaplan-Meier analysis and assessed the role of patient and treatment factors by Cox proportional hazards model. Findings 409 096 primary hip replacements were done to treat osteoarthritis. 1743 patients died within 90 days of surgery during 8 years, with a substantial secular decrease in mortality, from 0·56% in 2003 to 0·29% in 2011, even after adjustment for age, sex, and comorbidity. Several modifiable clinical factors were associated with decreased mortality according to an adjusted model: posterior surgical approach (hazard ratio HR 0·82, 95% CI 0·73–0·92; p=0·001), mechanical thromboprophylaxis (0·85, 0·74–0·99; p=0·036), chemical thromboprophylaxis with heparin with or without aspirin (0·79, 0·66–0·93; p=0·005), and spinal versus general anaesthetic (0·85, 0·74–0·97; p=0·019). Type of prosthesis was unrelated to mortality. Being overweight was associated with lower mortality (0·76, 0·62–0·92; p=0·006). Interpretation Postoperative mortality after hip joint replacement has fallen substantially. Widespread adoption of four simple clinical management strategies (posterior surgical approach, mechanical and chemical prophylaxis, and spinal anaesthesia) could, if causally related, reduce mortality further. Funding National Joint Registry for England and Wales.
Summary Background Understanding the risk factors for early death after knee replacement could help to reduce the risk of mortality after this procedure. We assessed secular trends in death within 45 ...days of knee replacement for osteoarthritis in England and Wales, with the aim of investigating whether any change that we recorded could be explained by alterations in modifiable perioperative factors. Methods We took data for knee replacements done for osteoarthritis in England and Wales between April 1, 2003, and Dec 31, 2011, from the National Joint Registry for England and Wales. Patient identifiers were used to link these data to the national mortality database and the Hospital Episode Statistics database to obtain details of death, sociodemographics, and comorbidity. We assessed mortality within 45 days by Kaplan-Meier analysis and assessed the role of patient and treatment factors by Cox proportional hazards models. Findings 467 779 primary knee replacements were done to treat osteoarthritis during 9 years. 1183 patients died within 45 days of surgery, with a substantial secular decrease in mortality from 0·37% in 2003 to 0·20% in 2011, even after adjustment for age, sex, and comorbidity. The use of unicompartmental knee replacement was associated with substantially lower mortality than was total knee replacement (hazard ratio HR 0·32, 95% CI 0·19–0·54, p<0·0005). Several comorbidities were associated with increased mortality: myocardial infarction (HR 3·46, 95% CI 2·81–4·14, p<0·0005), cerebrovascular disease (3·35, 2·7–4·14, p<0·0005), moderate/severe liver disease (7·2, 3·93–13·21, p<0·0005), and renal disease (2·18, 1·76–2·69, p<0·0005). Modifiable perioperative risk factors, including surgical approach and thromboprophylaxis were not associated with mortality. Interpretation Postoperative mortality after knee replacement has fallen substantially between 2003 and 2011. Efforts to further reduce mortality should concentrate more on older patients, those who are male and those with specific comorbidities, such as myocardial infarction, cerebrovascular disease, liver disease, and renal disease. Funding National Joint Registry for England and Wales.
The Atmospheric Infrared Sounder (AIRS) instrument onboard the NASA Aqua satellite is used to observe aurora associated with the CO2 4.26 μm emission. These observations are due to non‐local ...thermodynamic equilibrium (NLTE) resulting from the vibrational excitation of CO2, which arises in the process of auroral energetic particle precipitation, as opposed to the dayside NLTE occurring due to solar radiation. The observations are confirmed to be associated with aurora using the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) limb measurements and the SuperMAG Electrojet (SME) index. The high spectral resolution and low noise associated with the AIRS instrument allows for the emission spectrum to be calculated and confirmed to arise from CO2. Our new NLTE index values derived from AIRS provide the ability to globally measure auroral events associated with CO2 with a spatial resolution on the order of ∼13.5 km.
Plain Language Summary
The aurora are caused by energetic particle precipitation into Earth's atmosphere due to energy buildup and release in Earth's magnetic field from interaction with the solar wind. These energetic particles smash into Earth's atmosphere with high energy, and react with atoms and molecules in the atmosphere. There are many types of emissions of light that are associated with Earth's aurora. One of these emissions is the infrared emission centered near 4.26 μm associated with excited CO2 molecules. When CO2 is vibrationally excited through an exchange of energy with an N2 molecule excited by auroral particles, the CO2 molecule eventually relaxes from this state and releases a photon near 4.26 μm. This research presents a satellite observation from NASA's AIRS instrument allowing for the CO2 auroral emission to be viewed and mapped from space.
Key Points
A carbon dioxide infrared emission at 4.26 microns associated with the aurora is observed by the Atmospheric Infrared Sounder (AIRS) instrument
A new non‐local thermodynamic equilibrium index provides a quantitative measure of the carbon dioxide auroral‐associated emission
The AIRS auroral observations are confirmed by simultaneous Sounding of the Atmosphere using Broadband Emission Radiometry measurements and the SuperMAG Electrojet index
Acculturation has become a popular variable in research on health disparities among certain ethnic minorities, in the absence of serious reflection about its central concepts and assumptions. Key ...constructs such as what constitutes a culture, which traits pertain to the ethnic versus “mainstream” culture, and what cultural adaptation entails have not been carefully defined. Using examples from a systematic review of recent articles, this paper critically reviews the development and application of the concept of acculturation in US health research on Hispanics. Multiple misconceptions and errors in the central assumptions underlying the concept of acculturation are examined, and it is concluded that acculturation as a variable in health research may be based more on ethnic stereotyping than on objective representations of cultural difference.
To calculate the prevalence of developmental coordination disorder at 7 years of age by using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria in a large UK birth ...cohort.
Cases of developmental coordination disorder were defined by using data from the Avon Longitudinal Study of Parents and Children, a UK birth cohort. The motor coordination of >7000 children was assessed by using tests that measured manual dexterity, ball skills, and balance. The 5th percentile of the derived Avon Longitudinal Study of Parents and Children coordination impairment score was used to define severe motor coordination difficulties. Data from national handwriting tests and an activities-of-daily-living scale quantified the impact of poor coordination on daily life. Children with known neurologic conditions or an IQ of <70 were excluded.
Complete data were available from 6990 children aged 7 to 8 years who attended the coordination session and completed the writing test or activities-of-daily-living scale. One hundred nineteen children met criteria for developmental coordination disorder, resulting in a prevalence of 17 of 1000 children at a mean age of 7.5 years (SD: 2.9 months). An additional 222 children were considered as having "probable developmental coordination disorder" by using broader cut-offs for coordination testing and activities of daily living. There was an increased risk of developmental coordination disorder in families from lower socioeconomic backgrounds, in children with a birth weight of <2500 g, and those born before 37 weeks' gestation.
This is the first study to use strict criteria to define the prevalence of developmental coordination disorder in a representative cohort of UK children. A prevalence of 1.7% is lower than studies that have not taken into account the impact of poor motor coordination on daily living but indicates that poor coordination is an important, and often hidden, cause of disability in childhood.
To explore the associations between probable developmental coordination disorder (DCD) defined at age 7 years and mental health difficulties at age 9 to 10 years.
We analyzed of prospectively ...collected data (N = 6902) from the Avon Longitudinal Study of Parents and Children. "Probable" DCD was defined by using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria as those children below the 15th centile of the Avon Longitudinal Study of Parents and Children Coordination Test, with functional limitations in activities of daily living or handwriting, excluding children with neurologic difficulties or an IQ <70. Mental health was measured by using the child-reported Short Moods and Feelings Questionnaire and the parent-reported Strengths and Difficulties Questionnaire. Multiple logistic regression models, with the use of multiple imputation to account for missing data, assessed the associations between probable DCD and mental health difficulties. Adjustments were made for environmental confounding factors, and potential mediating factors such as verbal IQ, associated developmental traits, bullying, self-esteem, and friendships.
Children with probable DCD (N = 346) had an increased odds of self-reported depression, odds ratio: 2.08 (95% confidence interval: 1.36-3.19) and parent-reported mental health difficulties odds ratio: 4.23 (95% confidence interval: 3.10-5.77). The odds of mental health difficulties significantly decreased after accounting for verbal IQ, social communication, bullying, and self-esteem.
Children with probable DCD had an increased risk of mental health difficulties that, in part, were mediated through associated developmental difficulties, low verbal IQ, poor self-esteem, and bullying. Prevention and treatment of mental health difficulties should be a key element of intervention for children with DCD.
Background Understanding the risk factors for early death after knee replacement could help to reduce the risk of mortality after this procedure. We assessed secular trends in death within 45 days of ...knee replacement for osteoarthritis in England and Wales, with the aim of investigating whether any change that we recorded could be explained by alterations in modifiable perioperative factors. Methods We took data for knee replacements done for osteoarthritis in England and Wales between April 1, 2003, and Dec 31, 2011, from the National Joint Registry for England and Wales. Patient identifiers were used to link these data to the national mortality database and the Hospital Episode Statistics database to obtain details of death, sociodemographics, and comorbidity. We assessed mortality within 45 days by Kaplan-Meier analysis and assessed the role of patient and treatment factors by Cox proportional hazards models. Findings 467779 primary knee replacements were done to treat osteoarthritis during 9 years. 1183 patients died within 45 days of surgery, with a substantial secular decrease in mortality from 0.37% in 2003 to 0.20% in 2011, even after adjustment for age, sex, and comorbidity. The use of unicompartmental knee replacement was associated with substantially lower mortality than was total knee replacement (hazard ratio HR 0.32, 95% CI 0.19-0.54, p<0.0005). Several comorbidities were associated with increased mortality: myocardial infarction (HR 3.46, 95% CI 2.81-4.14, p<0.0005), cerebrovascular disease (3.35, 2.7-4.14, p<0.0005), moderate/severe liver disease (7.2, 3.93-13.21, p<0.0005), and renal disease (2.18, 1.76-2.69, p<0.0005). Modifiable perioperative risk factors, including surgical approach and thromboprophylaxis were not associated with mortality. Interpretation Postoperative mortality after knee replacement has fallen substantially between 2003 and 2011. Efforts to further reduce mortality should concentrate more on older patients, those who are male and those with specific comorbidities, such as myocardial infarction, cerebrovascular disease, liver disease, and renal disease. Funding National Joint Registry for England and Wales.
Time series of radiative cooling of the upper mesosphere and lower thermosphere (UMLT) by carbon dioxide (CO2) are examined for evidence of trends over 20 years. Radiative cooling rates in K day−1 ...provided by the SABER instrument are converted to time series of infrared power radiated from three distinct layers between 0.1 hPa and 0.0001 hPa (65–105 km). Linear regression against time and a predictor for solar variability provides estimates of the trend in exiting longwave radiation (ELR) from these layers. Trends in ELR are not significantly different from zero at 95% or 99% confidence in each layer. These results demonstrate energy conservation in the UMLT on decadal time scales and show that the UMLT continues to radiate the same amount of energy it receives despite cooling and contracting over two decades. These results are enabled by the long‐term stability of the SABER instrument calibration.
Plain Language Summary
The Earth's upper mesosphere and lower thermosphere (UMLT) is the region between approximately 65 and 105 km in altitude. Infrared radiation emitted by CO2 is a fundamental component of the energy budget of the UMLT. Carbon dioxide (CO2) is increasing in this region. The amount of infrared energy emitted by CO2, over time, must balance the amount of energy from sunlight that is absorbed in the UMLT. Observations from orbiting satellites over the past two decades have shown that the temperature in the UMLT is decreasing due to the increasing CO2. A decreasing temperature implies a decrease in infrared energy emitted by an object. Energy conservation, however, requires that the amount of infrared energy radiated from the UMLT balance the amount of energy received, regardless of the temperature. In this paper we show that there is no significant long‐term change with time (i.e., zero trend) in the infrared energy emitted from the UMLT even though the UMLT temperature has been decreasing for the last 20 years (and longer) due to increasing CO2. This result confirms that energy is conserved in a cooling and contracting UMLT.
Key Points
Time series of infrared power (W) radiated by CO2 from the upper mesosphere & lower thermosphere (UMLT) are developed
Trends in radiated power are not different from zero at 95% or 99% confidence in the three layers examined between 0.1 and 0.0001 hPa
Increasing CO2 reduces the UMLT temperature while radiating the same amount of energy over time, thus conserving energy
Updated night atomic oxygen concentration (O) profiles from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the National Aeronautics and Space Administration ...TIMED satellite are presented. These are derived from measurements of the OH(υ = 9 + 8) volume emission rates and photochemical balance relationships. The new night O concentrations are smaller than those originally derived in 2013 and yield physically realistic global annual mean energy budgets in the upper mesosphere and lower thermosphere. The update to the night O atom profiles is motivated by recent discovery and verification of large rates of collisional quenching of OH(υ) by atomic oxygen. The kinetic model relating the SABER‐observed OH emission rates to atomic oxygen is now consistent with these larger quenching rates and other literature values. The new, smaller SABER night O also confirms that SABER daytime ozone is too large. The new night O and OH(υ) model impacts the inference of day and night atomic hydrogen.
Plain Language Summary
An updated data set of night atomic oxygen in the terrestrial mesosphere is presented. The atomic oxygen is derived from measurements made by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument on the National Aeronautics and Space Administration TIMED satellite. Atomic oxygen is a critical component of the chemistry and energy budget of the mesosphere and lower thermosphere. The data set is a 16‐year record intended to replace a prior data set published in 2013. The new atomic oxygen data set covers the mesopause region, approximately 80 to 100 km in altitude. The major change is that the new atomic oxygen concentrations are significantly smaller than the original data set. The new data yield a physically realistic global annual mean energy budget, in contrast to the original data set. A significant consequence of the new night data set is that the SABER daytime ozone concentrations (derived from measurements of 9.6 μm emission) are too large, confirming previous suggestions published in the literature. The results also impact the atomic hydrogen derived from SABER, both day and night.
Key Points
Updated SABER night atomic oxygen data sets for all 16 years of mission and concentrations are approximately 25% smaller at peak than baseline data set
Daytime SABER upper mesospheric ozone is confirmed to be large by ~25% as a consequence
New data yield physically realistic energy budget that has approximate balance between heating and cooling on global annual mean basis
Patients undergoing primary total joint replacement are selected for surgery and thus (other than having a transiently increased mortality rate postoperatively) have a lower mortality rate than age ...and sex-matched individuals do. Understanding the causes of death following joint replacement would allow targeted strategies to reduce the risk of death and optimize outcome. We aimed to determine the rates and causes of mortality for patients undergoing primary total hip or knee replacement compared with individuals in the general population who were matched for age and sex.
We compared causes and rates of mortality between age and sex-matched individuals in the general population (National Joint Registry for England, Wales and Northern Ireland; Hospital Episode Statistics; and Office for National Statistics) and a linked cohort of 332,734 patients managed with total hip replacement (26,766 of whom died before the censoring date) and 384,291 patients managed with primary total knee replacement (29,802 of whom died before the censoring date) from 2003 through 2012.
The main causes of death were malignant neoplasms (33.8% 9,037 of 26,766 deaths in patients with total hip replacement and 33.3% 9,917 of 29,802 deaths in patients with total knee replacement), circulatory system disorders (32.8% 8,784 of the deaths in patients with total hip replacement and 33.3% 9,932 of the deaths in patients with total knee replacement), respiratory system disorders (10.9% 2,928 of the deaths in patients with total hip replacement and 9.8% 2,932 of the deaths in patients with total knee replacement), and digestive system diseases (5.5% 1,465 of the deaths in patients with total hip replacement and 5.3% 1,572 of the deaths in patients with total knee replacement). There was a relative reduction in mortality (39%) compared with the individuals in the general population that equalized to the rate in the general population by 7 years for hips (overall standardized mortality ratio SMR, 0.61; 95% confidence interval CI, 0.60 to 0.62); for knees, the relative reduction (43%) partially attenuated by 7 years but still had not equalized to the rate in the general population (overall SMR, 0.57; 95% CI, 0.56 to 0.57). Ischemic heart disease was the most common cause of death within 90 days (29% 431 of the deaths in patients with primary hip replacement and 31% 436 of the deaths in patients with primary knee replacement). There was an elevated risk of death from circulatory, respiratory, and (most markedly) digestive system-related causes within 90 days postoperatively compared with 91 days to 1 year postoperatively.
Ischemic heart disease is the leading cause of death in the 90 days following total joint replacement, and there is an increase in postoperative deaths associated with digestive system-related disease following joint replacement. Interventions targeted at reducing these diseases may have the largest effect on mortality in total joint replacement patients.
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
PDF
