BACKGROUND
Little is known about the association between acute mental changes and adverse outcomes in hospitalized adults with COVID‐19.
OBJECTIVES
To investigate the occurrence of delirium in ...hospitalized patients with COVID‐19 and explore its association with adverse outcomes.
DESIGN
Longitudinal observational study.
SETTING
Tertiary university hospital dedicated to the care of severe cases of COVID‐19 in São Paulo, Brazil.
PARTICIPANTS
A total of 707 patients, aged 50 years or older, consecutively admitted to the hospital between March and May 2020.
MEASUREMENTS
We completed detailed reviews of electronic medical records to collect our data. We identified delirium occurrence using the Chart‐Based Delirium Identification Instrument (CHART‐DEL). Trained physicians with a background in geriatric medicine completed all CHART‐DEL assessments. We complemented our baseline clinical information using telephone interviews with participants or their proxy. Our outcomes of interest were in‐hospital death, length of stay, admission to intensive care, and ventilator utilization. We adjusted all multivariable analyses for age, sex, clinical history, vital signs, and relevant laboratory biomarkers (lymphocyte count, C‐reactive protein, glomerular filtration rate, D‐dimer, and albumin).
RESULTS
Overall, we identified delirium in 234 participants (33%). On admission, 86 (12%) were delirious. We observed 273 deaths (39%) in our sample, and in‐hospital mortality reached 55% in patients who experienced delirium. Delirium was associated with in‐hospital death, with an adjusted odds ratio of 1.75 (95% confidence interval = 1.15–2.66); the association held both in middle‐aged and older adults. Delirium was also associated with increased length of stay, admission to intensive care, and ventilator utilization.
CONCLUSION
Delirium was independently associated with in‐hospital death in adults aged 50 years and older with COVID‐19. Despite the difficulties for patient care during the pandemic, clinicians should routinely monitor delirium when assessing severity and prognosis of COVID‐19 patients.
The significance and cause of the decline in biomass burning across the Americas after ad 1500 is a topic of considerable debate. We synthesized charcoal records (a proxy for biomass burning) from ...the Americas and from the remainder of the globe over the past 2000 years, and compared these with paleoclimatic records and population reconstructions. A distinct post-ad 1500 decrease in biomass burning is evident, not only in the Americas, but also globally, and both are similar in duration and timing to ‘Little Ice Age’ climate change. There is temporal and spatial variability in the expression of the biomass-burning decline across the Americas but, at a regional–continental scale, ‘Little Ice Age’ climate change was likely more important than indigenous population collapse in driving this decline.
It is widely accepted, based on data from the last few decades and on model simulations, that anthropogenic climate change will cause increased fire activity. However, less attention has been paid to ...the relationship between abrupt climate changes and heightened fire activity in the paleorecord. We use 35 charcoal and pollen records to assess how fire regimes in North America changed during the last glacial-interglacial transition (15 to 10 ka), a time of large and rapid climate changes. We also test the hypothesis that a comet impact initiated continental-scale wildfires at 12.9 ka; the data do not support this idea, nor are continent-wide fires indicated at any time during deglaciation. There are, however, clear links between large climate changes and fire activity. Biomass burning gradually increased from the glacial period to the beginning of the Younger Dryas. Although there are changes in biomass burning during the Younger Dryas, there is no systematic trend. There is a further increase in biomass burning after the Younger Dryas. Intervals of rapid climate change at 13.9, 13.2, and 11.7 ka are marked by large increases in fire activity. The timing of changes in fire is not coincident with changes in human population density or the timing of the extinction of the megafauna. Although these factors could have contributed to fire-regime changes at individual sites or at specific times, the charcoal data indicate an important role for climate, and particularly rapid climate change, in determining broad-scale levels of fire activity.
Version 1 of the Global Charcoal Database is now available for regional fire history reconstructions, data exploration, hypothesis testing, and evaluation of coupled climate–vegetation–fire model ...simulations. The charcoal database contains over 400 radiocarbon-dated records that document changes in charcoal abundance during the Late Quaternary. The aim of this public database is to stimulate cross-disciplinary research in fire sciences targeted at an increased understanding of the controls and impacts of natural and anthropogenic fire regimes on centennial-to-orbital timescales. We describe here the data standardization techniques for comparing multiple types of sedimentary charcoal records. Version 1 of the Global Charcoal Database has been used to characterize global and regional patterns in fire activity since the last glacial maximum. Recent studies using the charcoal database have explored the relation between climate and fire during periods of rapid climate change, including evidence of fire activity during the Younger Dryas Chronozone, and during the past two millennia.
Age–depth relationships in sedimentary archives such as lakes, wetlands and bogs are non-linear with irregular probability distributions associated with calibrated radiocarbon dates. Bayesian ...approaches are thus well-suited to understanding relationships between age and depth for use in paleoecological studies. Bayesian models for the accumulation of sediment and organic matter within basins combine dated material from one or more records with prior information about the behavior of deposition times (yr/cm) based on expert knowledge. Well-informed priors are essential to good modeling of the age–depth relationship, but are particularly important in cases where data may be sparse (e.g., few radiocarbon dates), or unclear (e.g., age-reversals, coincident dates, age offsets, outliers and dates within a radiocarbon plateau).
Here we assessed Holocene deposition times using 204 age–depth models obtained from the Neotoma Paleoecology Database (www.neotomadb.org) for both lacustrine and palustrine environments across the northeastern United States. These age–depth models were augmented using biostratigraphic events identifiable within pollen records from the northeastern United States during the Holocene and late-Pleistocene.
Deposition times are significantly related to depositional environment (palustrine and lacustrine), sediment age, and sediment depth. Spatial variables had non-significant relationships with deposition time when site effects were considered. The best-fit model was a generalized additive mixed model that relates deposition time to age, stratified by depositional environment with site as a random factor. The best-fit model accounts for 63.3% of the total deviance in deposition times. The strongly increasing accumulation rates of the last 500–1000 years indicate that gamma distributions describing lacustrine deposition times (α = 1.08, β = 18.28) and palustrine deposition times (α = 1.23, β = 22.32) for the entire Holocene may be insufficient for Bayesian approaches since there is strong variation in the gamma parameters both in the most recent sediments and throughout the Holocene. Time-averaged gamma distributions for lacustrine (α = 1.35, β = 19.64) and palustrine samples (α = 1.40, β = 20.72) show lower overall deposition times, but variability remains. The variation in gamma parameters through time may require the use of multiple gamma distributions during the Holocene to generate accurate age–depth models. We present estimates of gamma parameters for deposition times at 1000 yr intervals. The parameters generated in this study can be used directly within Bacon to act as Bayesian priors for sedimentary age models.
Display omitted
► Basin deposition times across the northeastern U.S.A. vary during the Holocene. ► Lacustrine and palustrine basins show different patterns over time. ► Empirical gamma parameters are presented for Bayesian modeling.
Fires have influenced atmospheric composition and climate since the rise of vascular plants, and satellite data has shown the overall global extent of fires. Our knowledge of historic fire emissions ...has progressively improved over the past decades due mostly to the development of new proxies and the improvement of fire models. Currently there is a suite of proxies including sedimentary charcoal records, measurements of fire-emitted trace gases and black carbon stored in ice and firn, and visibility observations. These proxies provide opportunities to extrapolate emissions estimates based on satellite data starting in 1997, but each proxy has strengths and weaknesses regarding, for example, the spatial and temporal extents over which they are representative. We developed a new historic biomass burning emissions dataset starting in 1750 that merges the satellite record with several existing proxies, and uses the average of six models from the Fire Model Intercomparison Project (FireMIP) protocol to estimate emissions when the available proxies had limited coverage. According to our approach, global biomass burning emissions were relatively constant with 10-year averages varying between 1.8 and 2.3 petagrams of carbon per year. Carbon emissions increased only slightly over the full time period and peaked during the 1990's after which they decreased gradually. There is substantial uncertainty in these estimates and patterns varied depending on choices regarding data representation, especially on regional scales. The observed pattern in fire carbon emissions is for a large part driven by African fires, which accounted for 58 percent of global fire carbon emissions. African fire emissions declined since about 1950 due to conversion of savanna to cropland, and this decrease is partially compensated for by increasing emissions in deforestation zones of South America and Asia. These global fire emissions estimates are mostly suited for global analyses and will be used in the Coupled Model Intercomparison Project Phase 6 (CMIP6) simulations.
Black or elemental carbon (EC), including soot and char, are byproducts of anthropogenic fossil‐fuel and biomass burning, and also of wildfires. EC, and particularly soot, strongly affects ...atmospheric chemistry and physics and thus radiative forcing; it can also alter regional climate and precipitation. Pre‐industrial variations in EC as well as its source areas and controls however, are poorly known. Here we use a lake‐sediment EC record from China to reconstruct Holocene variations in soot (combustion emissions formed via gas‐to‐particle conversion processes) and char (combustion residues from pyrolysis) measured with a thermal/optical method. Comparisons with sedimentary charcoal records (i.e., particles measured microscopically), climate and population data are used to infer variations in biomass burning and its controls. During the Holocene, positive correlations are observed between EC and an independent index of regional biomass burning. Negative correlations are observed between EC and monsoon intensity, and tree cover inferred from arboreal pollen percentages. Abrupt declines in temperature are also linked with widespread declines in fire. Our results 1) confirm the robustness of a relatively new method for reconstructing variations in EC; 2) document variations in regional biomass burning; 3) support a strong climatic control of biomass burning throughout the Holocene; and 4) indicate that char levels are higher today than at any time during the Holocene.
Key Points
Sedimentary elemental carbon reflects regional biomass burning
Holocene biomass burning in China varies with moisture and temperature
Char levels in eastern Asia today are higher than at any time in the Holocene
Current recommendations to assess sarcopenia requiring specialized equipment hinder its use as a prognostic tool in busy acute settings.
To investigate the prognostic value of a rapid sarcopenia ...measure in acutely ill older outpatients for 1-year adverse outcomes.
Prospective study with 665 acutely ill older adults (mean age 78.7 ± 8.3 years; 63% women) in need of intensive management to avoid hospital admission. Sarcopenia was screened upon admission, defined as the presence of both low muscle strength and low muscle mass. Low muscle strength was determined by handgrip strength according to the cutoffs of the Foundation for the National Institutes of Health (<16 kg for women and <26 kg for men). Low muscle mass was assessed by calf circumference, a validated surrogate measure of skeletal muscle mass, using previously established thresholds (≤33 cm for women and ≤34 cm for men). Outcomes were time to hospitalization, new dependence in basic activities of daily living (ADL), worsening walking ability, and death. To investigate the association of sarcopenia and its components with outcomes we used hazard models, considering death as a competing risk, adjusted for sociodemographic factors, Charlson comorbidity index, cognitive impairment, depressive symptoms, and weight loss.
On admission, 203 (31%) patients had sarcopenia. Comparing 1-year adverse outcomes between older adults with and without sarcopenia, respectively, cumulative incidences for hospitalization were 46% vs 32% (adjusted sub-hazard ratio sHR = 1.53; 95% CI = 1.16–2.04), for new ADL dependence, 47% vs 24% (adjusted sHR = 1.78; 95% CI = 1.31–2.42), for worsening walking ability, 28% vs 13% (adjusted sHR = 1.93; 95% CI = 1.28–2.90), and for death, 22% vs 10% (adjusted HR = 1.69; 95% CI = 1.05–2.73). Low muscle strength alone was associated with all outcomes, and low muscle mass was associated with all outcomes except mortality.
Sarcopenia was a strong predictor of 1-year adverse outcomes among acutely ill older outpatients. Combining handgrip strength with calf circumference may be a practical and efficient approach to screen for sarcopenia, and thereby identify high-risk older adults in busy clinical settings.
•Sarcopenia can identify older people at risk of poor outcomes.•Time pressure and few resources hinder the assess of sarcopenia in busy settings.•Grip strength and calf circumference are measures quickly assessed in busy settings.•Handgrip strength and calf circumference captures the key elements of sarcopenia.•This practical sarcopenia screening predicts poor outcomes after acute care.
PDF
