Changes in PESI scores predict mortality in intermediate-risk patients with acute pulmonary embolism

Although the Pulmonary Embolism Severity Index (PESI) accurately identifies 35% of patients with acute pulmonary embolism (PE) as being low risk, some patients deemed high risk by the PESI on admission might be treated safely in the outpatient environment. This retrospective cohort study included a total of 304 consecutive patients with acute PE, classified at the time of hospital admission into PESI class III. The PESI was recalculated 48 h after admission (PESI(48)) and each patient reclassified into the corresponding risk category. The primary outcome of the study was all-cause mortality between day 2 and day 30 after PE diagnosis. 26 (8.5%) patients (95% CI 5.4-11.7%) died between day 2 and day 30 after PE diagnosis. Investigators reclassified 83 (27.3%) patients (95% CI 22.3-32.3%) as low risk (classes I and II) at 48 h. 30-day mortality in these patients was 1.2% (95% CI 0-3.5%) as opposed to 11.3% (95% CI 7.1-15.5%) in those who remained high risk. The net improvement in reclassification was estimated at 54% (p<0.001). In a cohort of intermediate-risk patients with acute PE, calculation of the PESI(48) allows identification of those patients at very low risk of dying during the first month of follow-up.

Land use imperils plant and animal community stability through changes in asynchrony rather than diversity

Human land use may detrimentally affect biodiversity, yet long-term stability of species communities is vital for maintaining ecosystem functioning. Community stability can be achieved by higher species diversity (portfolio effect), higher asynchrony across species (insurance hypothesis) and higher abundance of populations. However, the relative importance of these stabilizing pathways and whether they interact with land use in real-world ecosystems is unknown. We monitored inter-annual fluctuations of 2,671 plant, arthropod, bird and bat species in 300 sites from three regions. Arthropods show 2.0-fold and birds 3.7-fold higher community fluctuations in grasslands than in forests, suggesting a negative impact of forest conversion. Land-use intensity in forests has a negative net impact on stability of bats and in grasslands on birds. Our findings demonstrate that asynchrony across species—much more than species diversity alone—is the main driver of variation in stability across sites and requires more attention in sustainable management.