Background We explore longitudinal trajectories of clinical indicators, patient-reported outcomes, and hospitalizations, in the years preceding death in a population of older patients with advanced... Show moreBackground We explore longitudinal trajectories of clinical indicators, patient-reported outcomes, and hospitalizations, in the years preceding death in a population of older patients with advanced chronic kidney disease (CKD). Methods The EQUAL study is a European observational prospective cohort study with an incident eGFR Results We included 661 decedents with a median time to death of 2.0 years (IQR 0.9-3.2). During the years preceding death, eGFR, Subjective Global Assessment score, and blood pressure declined, with accelerations seen at 6 months preceding death. Serum hemoglobin, hematocrit, cholesterol, calcium, albumin, and sodium values declined slowly during follow-up, with accelerations observed between 6 and 12 months preceding death. Physical and mental quality of life declined linearly throughout follow-up. The number of reported symptoms was stable up to 2 years prior to death, with an acceleration observed at 1 year prior to death. The rate of hospitalization was stable at around one hospitalization per person year, increasing exponentially at 6 months preceding death. Conclusions We identified clinically relevant physiological accelerations in patient trajectories that began similar to 6 to 12 months prior to death, which are likely multifactorial in nature, but correlate with a surge in hospitalizations. Further research should focus on how to effectively use this knowledge to inform patient and family expectations, to benefit the planning of (end-of-life) care, and to establish clinical alert systems. Show less
Climate change poses a significant threat to global biodiversity, but freshwater fishes have been largely ignored in climate change assessments. Here, we assess threats of future flow and water... Show moreClimate change poses a significant threat to global biodiversity, but freshwater fishes have been largely ignored in climate change assessments. Here, we assess threats of future flow and water temperature extremes to similar to 11,500 riverine fish species. In a 3.2 degrees C warmer world (no further emission cuts after current governments' pledges for 2030), 36% of the species have over half of their present-day geographic range exposed to climatic extremes beyond current levels. Threats are largest in tropical and sub-arid regions and increases in maximum water temperature are more threatening than changes in flow extremes. In comparison, 9% of the species are projected to have more than half of their present-day geographic range threatened in a 2 degrees C warmer world, which further reduces to 4% of the species if warming is limited to 1.5 degrees C. Our results highlight the need to intensify (inter)national commitments to limit global warming if freshwater biodiversity is to be safeguarded. Show less
Existing methods for applying the planetary boundary concept in life cycle assessment are not sufficiently spatially and temporally resolved. Here, we develop a new method for freshwater use based... Show moreExisting methods for applying the planetary boundary concept in life cycle assessment are not sufficiently spatially and temporally resolved. Here, we develop a new method for freshwater use based on the safe operating space (SOS) at watershed-level. The SOS is based on the concept of environmental flow requirements, which is the share of mean monthly flow that should be reserved to achieve or maintain "fair conditions" of aquatic ecosystems. The method is composed of two steps. First, water consumption is multiplied by a characterization factor, which converts it to an environmental impact, expressed as an area-equivalent of a watershed's mean monthly flow. Second, the environmental impact is compared to an assigned share of SOS to determine if the activity causing it can be considered environmentally sustainable, with respect to a chosen principle for sharing the SOS.The method is demonstrated for a case study on water consumed for irrigation in open-field tomato production in 27 watersheds, spanning 10 countries and 5 continents, based on data for 316 farms in the year 2014. Water consumption was modelled from crop characteristics, climatic data and the assumed type of irrigation system. Two principles, "status quo" and "gross value added", were illustratively applied for the assignment of SOS to 1 tonne of tomatoes.The characterization factors developed span two orders of magnitude from 10th to 90th percentile, which shows the relevance of a spatially and temporally explicit assessment. In the case study, the characterization factors largely determine the high variability in the resulting environmental impacts between watersheds, which ranged from 400 m(2) to 50,000 m(2) per tonne of tomatoes. The analysis would suggest that the freshwater use by current tomato farming is environmentally sustainable in all months in a maximum of 2 of the 27 watersheds with respect to the two principles applied for sharing the SOS.The method can be used as a basis to identify potential "planetary boundary hotspots" in the life cycle of products and to inform appropriate interventions. Two key challenges are the lack of appropriate spatial and temporal data in current life cycle inventories and the choice of sharing principle for assigning the SOS. Show less
Dams contribute to water security, energy supply, and flood protection but also fragment habitats of freshwater species. Yet, a global species-level assessment of dam-induced fragmentation is... Show moreDams contribute to water security, energy supply, and flood protection but also fragment habitats of freshwater species. Yet, a global species-level assessment of dam-induced fragmentation is lacking. Here, we assessed the degree of fragmentation of the occurrence ranges of similar to 10,000 lotic fish species worldwide due to similar to 40,000 existing large dams and similar to 3,700 additional future large hydropower dams. Per river basin, we quantified a connectivity index (CI) for each fish species by combining its occurrence range with a high-resolution hydrography and the locations of the dams. Ranges of nondiadromous fish species were more fragmented (less connected) (CI = 73 +/- 28%; mean +/- SD) than ranges of di-adromous species (CI = 86 +/- 19%). Current levels of fragmentation were highest in the United States, Europe, South Africa, India, and China. Increases in fragmentation due to future dams were especially high in the tropics, with declines in CI of similar to 20 to 40 percentage points on average across the species in the Amazon, Niger, Congo, Salween, and Mekong basins. Our assessment can guide river management at multiple scales and in various domains, including strategic hydropower planning, identification of species and basins at risk, and prioritization of restoration measures, such as dam removal and construction of fish bypasses. Show less
Background-People with reduced glomerular filtration rate (GFR) often have elevated cardiac troponin T (cTnT) levels. It remains unclear how cTnT levels develop over time in those with chronic... Show moreBackground-People with reduced glomerular filtration rate (GFR) often have elevated cardiac troponin T (cTnT) levels. It remains unclear how cTnT levels develop over time in those with chronic kidney disease (CKD). The aim of this study was to prospectively study the association between cTnT and GFR over time in older advanced-stage CKD patients not on dialysis.Methods and Results-The EQUAL (European Quality Study) study is an observational prospective cohort study in stage 4 to 5 CKD patients aged >= 65 years not on dialysis (incident estimated GFR, <20 mL/min/1.73 m(2)). The EQUAL cohort used for the purpose of this study includes 171 patients followed in Sweden between April 2012 and December 2018. We used linear mixed models, adjusted for important groups of confounders, to investigate the effect of both measured GFR and estimated GFR on high-sensitivity cTnT (hs-cTnT) trajectory over 4 years. Almost all patients had at least 1 hs-cTnT measurement elevated above the 99th percentile of the general reference population (<= 14 ng/L). On average, hs-cTnT increased by 16%/year (95% CI, 13-19; P<0.0001). Each 15 mL/min/1.73 m(2) lower mean estimated GFR was associated with a 23% (95% CI, 14-31; P<0.0001) higher baseline hs-cTnT and 9% (95% CI, 5-13%; P<0.0001) steeper increase in hs-cTnT. The effect of estimated GFR on hs-cTnT trajectory was somewhat lower than a previous myocardial infarction (15%), but higher than presence of diabetes mellitus (4%) and male sex (5%).Conclusions-In CKD patients, hs-cTnT increases over time as renal function decreases. Lower CKD stage (each 15 mL/min/1.73 m2 lower) is independently associated with a steeper hs-cTnT increase over time in the same range as other established cardiovascular risk factors. Show less
Streamflow data is highly relevant for a variety of socio-economic as well as ecological analyses or applications, but a high-resolution global streamflow dataset is yet lacking. We created FLO1K,... Show moreStreamflow data is highly relevant for a variety of socio-economic as well as ecological analyses or applications, but a high-resolution global streamflow dataset is yet lacking. We created FLO1K, a consistent streamflow dataset at a resolution of 30 arc seconds (-1 km) and global coverage. FLO1K comprises mean, maximum and minimum annual flow for each year in the period 1960-2015, provided as spatially continuous gridded layers. We mapped streamflow by means of artificial neural networks (ANNs) regression. An ensemble of ANNs were fitted on monthly streamflow observations from 6600 monitoring stations worldwide, i.e., minimum and maximum annual flows represent the lowest and highest mean monthly flows for a given year. As covariates we used the upstream-catchment physiography (area, surface slope, elevation) and year-specific climatic variables (precipitation, temperature, potential evapotranspiration, aridity index and seasonality indices). Confronting the maps with independent data indicated good agreement (R-2 values up to 91%). FLO1K delivers essential data for freshwater ecology and water resources analyses at a global scale and yet high spatial resolution.[GRAPHICS]. Show less
Quantifying mean annual flow of rivers (MAF) at ungauged sites is essential for assessments of global water supply, ecosystem integrity and water footprints. MAF can be quantified with spatially... Show moreQuantifying mean annual flow of rivers (MAF) at ungauged sites is essential for assessments of global water supply, ecosystem integrity and water footprints. MAF can be quantified with spatially explicit process-based models, which might be overly time-consuming and data-intensive for this purpose, or with empirical regression models that predict MAF based on climate and catchment characteristics. Yet, regression models have mostly been developed at a regional scale and the extent to which they can be extrapolated to other regions is not known. In this study, we developed a global-scale regression model for MAF based on a dataset unprecedented in size, using observations of discharge and catchment characteristics from 1885 catchments worldwide, measuring between 2 and 10(6) km(2). In addition, we compared the performance of the regression model with the predictive ability of the spatially explicit global hydrological model PCR-GLOBWB by comparing results from both models to independent measurements. We obtained a regression model explaining 89% of the variance in MAF based on catchment area and catchment averaged mean annual precipitation and air temperature, slope and elevation. The regression model performed better than PCR-GLOBWB for the prediction of MAF, as root-mean-square error (RMSE) values were lower (0.29-0.38 compared to 0.49-0.57) and the modified index of agreement (d) was higher (0.80-0.83 compared to 0.72-0.75). Our regression model can be applied globally to estimate MAF at any point of the river network, thus providing a feasible alternative to spatially explicit process based global hydrological models. (C) 2016 Elsevier B.V. All rights reserved. Show less
