Heat Stress is Associated with Reduced Health Status in Pulmonary Arterial Hypertension: A Prospective Study Cohort

Background

Summer heat waves with temperature extremes are becoming more frequent with growing numbers in morbidity and mortality in patients with respiratory diseases. The aim of this study was to evaluate the ramifications of heat stress (temperature >25 °C) on the health status of patients with pulmonary arterial hypertension (PAH).

Methods

Fifteen patients with PAH (mean age = 66.7 ± 5.2 years) continuously wore an accelerometer from April 1 to September 30, 2011, and their daily step count was recorded. In addition, patients kept a diary to record data on seven standardized questions regarding their daily symptoms. Echocardiography, 6-minute walk test, NTproBNP, and Modified Medical Research Council Scale (MMRC) were assessed at baseline and at the end of the study after 6 months.

Results

On heat-stress days, patients showed significantly more symptoms and lower total steps/day compared to thermal comfort days (3,995 ± 2,013 steps/day vs. 5,567 ± 2,434 steps/day, respectively; P < 0.001). There was a significant negative correlation between total steps/day and Temp_max (R = ?0.47; P < 0.001) and humidity (R = ?0.34; P < 0.001). A significant positive correlation was found between daily symptoms and Temp_max (R = +0.79; P < 0.001) and humidity (R = +0.23; P < 0.001).

Conclusions

Heat stress is associated with a compromised clinical status in patients with PAH. Adaptation strategies must be implemented to prevent heart-related morbidity, including therapeutic adjustments and adequate room cooling in the patient’s home and at the hospital.     

Global water resources affected by human interventions and climate change

Humans directly change the dynamics of the water cycle through dams constructed for water storage, and through water withdrawals for industrial, agricultural, or domestic purposes. Climate change is expected to additionally affect water supply and demand. Here, analyses of climate change and direct human impacts on the terrestrial water cycle are presented and compared using a multimodel approach. Seven global hydrological models have been forced with multiple climate projections, and with and without taking into account impacts of human interventions such as dams and water withdrawals on the hydrological cycle. Model results are analyzed for different levels of global warming, allowing for analyses in line with temperature targets for climate change mitigation. The results indicate that direct human impacts on the water cycle in some regions, e.g., parts of Asia and in the western United States, are of the same order of magnitude, or even exceed impacts to be expected for moderate levels of global warming (+2 K). Despite some spread in model projections, irrigation water consumption is generally projected to increase with higher global mean temperatures. Irrigation water scarcity is particularly large in parts of southern and eastern Asia, and is expected to become even larger in the future.Terrestrial water fluxes are affected by both climate and direct human interventions, e.g., dam operations and water withdrawals. Climate change is expected to alter the water cycle and will subsequently impact water availability and demand. Several hydrologic modeling studies have focused on climate change impacts on discharge in large river basins or global terrestrial areas under naturalized conditions using a single hydrologic model forced with multiple climate projections (1, 2). Recently, hydrological projections from eight global hydrological models (GHMs) were compared (3). In many areas, there was a large spread in projected runoff changes within the climate–hydrology modeling chain. However, at high latitudes there was a clear increase in runoff, whereas some midlatitude regions showed a robust signal of reduced runoff. The study also concluded that the choice of GHM adds to the uncertainty for hydrological change caused by the choice of atmosphere–ocean general circulation models (hereafter called GCMs) (3). Expected runoff increases in the north and decreases in parts of the middle latitudes have been found also when analyzing runoff from 23 GCMs (4).These studies focused on the naturalized hydrological cycle, i.e., the effects of direct human interventions were not taken into account. However, in many river basins humans substantially alter the hydrological cycle by constructing dams and through water withdrawals. Reservoir operations alter the timing of discharge, although mean annual discharge does not necessarily change much. A study with the water balance model (WBM) showed that the impact of human disturbances, i.e., dams and water consumption, in some river basins is equal to or greater than the impact of expected climate changes on annual runoff over the next 40 y (5). Also, rising water demands are found to outweigh global warming in defining the state of global water systems in the near future (6). Water for irrigation is the largest water use sector, currently accounting for about 70% of global water withdrawals and nearly 90% of consumptive water use (7). A recent synthesis of simulations from seven GHMs found that irrigation water consumption currently amounts to 1,250 km³⋅y⁻¹ (±25%) and that considerable differences among models appear in the spatiotemporal patterns of water consumption (8).Direct comparisons of the climate impact and human intervention modeling studies can be difficult given that the setups are not identical, i.e., the input forcing data and climate models vary. Also, because of the uncertainty of model-specific results, a multimodel approach is preferable in impact modeling studies (3, 9). This approach is similar to assessments performed within the climate community. Here, multimodel results on current and future water availability and consumption at the global scale from the Water Model Intercomparison Project (WaterMIP) within the European Union Water and Global Change (EU WATCH) project (9, 10), and Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP) (11) are presented. (Information on how to get access to WaterMIP and ISI-MIP simulation results can be found at www.eu-watch.org and www.isi-mip.org, respectively.) Results from these two projects are synthesized to obtain a large ensemble of impact model results. The integration of results from the different projects is achieved by extracting impacts for time periods of global mean temperature (GMT) increases of 2 and 3 K from the simulations, largely following the method of Tang and Lettenmaier (4). The advantage of this approach is that it allows presenting results in a way that is in line with temperature targets used in climate mitigation discussions.Other studies have focused on future water scarcity using results from WaterMIP and ISI-MIP, but have analyzed changes of naturalized runoff only (3, 12). We here aim to fill this knowledge gap by comparing the different impacts from climate change and direct human impacts and analyzing their interplay. The models included take into account water withdrawals and consumption in different sectors; for more information, see Models and Data and Supporting Information, SI Models and Data. The objectives of this study are to (i) assess the relative contribution of anthropogenic impacts and climate change to river basin scale water fluxes, and (ii) identify areas where climate change can be expected to cause substantial changes in water consumption and water scarcity, focusing on water for irrigation. The effects of future changes in irrigated areas or irrigation practices are not taken into account, and only dams that currently exist are included in the analyses. In this paper, simulations considering man-made reservoirs, water withdrawals, and water consumption are referred to as human impact simulations, whereas the simulations without these disturbances are referred to as naturalized simulations. The results are mainly presented in a way intended to give an overview of impacts at larger spatial scales (river basin and country levels). However, some finer-scale results are included to reveal effects that can be concealed at coarse spatial scales.     

Significance of vomiting for hyperamylasemia and sialadenosis in patients with eating disorders

The authors investigated the significance of vomiting for hyperamylasemia and sialadenosis in patients with bulimia nervosa. Hyperamylasemia was found in 61% of the bulimics and in 20% of the restrictor anorectics but in no patients with binge-eating syndrome. In more than three fourths of the bulimics there was a close positive correlation between the frequency of vomiting and total serum amylase levels. Both frequency and type of vomiting seem to be relevant to the extent of salivary gland enlargement. The significance of vomiting for the etiopathology of hyperamylasemia and for the diagnosis of eating disorders will be discussed. © 1993 by John Wiley & Sons, Inc.     

Rationale and design of the AdaptResponse trial: a prospective randomized study of cardiac resynchronization therapy with preferential adaptive left ventricular‐only pacing

The AdaptResponse trial is designed to test the hypothesis that preferential adaptive left ventricular‐only pacing with the AdaptivCRT^® algorithm reduces the incidence of the combined endpoint of all‐cause mortality and intervention for heart failure (HF) decompensation, compared with conventional cardiac resynchronization therapy (CRT), among patients with a CRT indication, left bundle branch block (LBBB) and normal atrioventricular (AV) conduction. The AdaptResponse study is a prospective, randomized, controlled, single‐blinded, multicentre, clinical trial ( ClinicalTrials.gov Identifier: NCT02205359), conducted at up to 200 centres worldwide. Following enrolment and baseline assessment, eligible subjects will be implanted with a CRT system containing the AdaptivCRT algorithm, and randomized in a 1:1 fashion to either a treatment (‘AdaptivCRT’) or control (‘Conventional CRT’) group. The study is designed to observe a primary endpoint in 1100 patients (‘event‐driven’) and approximately 3000 patients will be randomized. The primary endpoint is the composite of all‐cause mortality and intervention for HF decompensation; secondary endpoints include all‐cause mortality, intervention for HF decompensation, clinical composite score (CCS) at 6 months, atrial fibrillation, quality of life measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ), health outcome measured by the EQ‐5D instrument, all‐cause readmission after a HF admission, and cost‐effectiveness. The AdaptResponse clinical trial is powered to assess clinical endpoints and is expected to provide definitive evidence on the incremental utility of AdaptivCRT‐enhanced CRT systems.     

Weisheitszähne — Stationär behandlungsbedürftige Komplikationen

Background

In view of the conflicting guidelines issued by national and international scientific societies, debate about the indications for prophylactic extraction of wisdeom teeth is ongoing. This prospective study was therefore set up to explore the complications associated with wisdom teeth and requiring in-patient treatment.

Patients and Methods

From January /2003 to December 2003, 21 subjects were admitted for treatment of complications associated with wisdom teeth. The medical history was recorded for each of these patients, as were the cause and type of the complications. The parameter used to quantify the severity of any infections was the CRP, and the overall clinical complexity level of each case was assessed by the length of stay in hospital (and the duration of intensive care if this had been necessary). The characteristics of patients in the group with postoperative complications were compared to those of patients with complications attributable to pericoronitis. Moreover, complications in patients who had undergone prophylactic extraction of wisdom teeth that had not been causing any symptoms were compared with those in patients whose wisdom teeth had been extracted because of morbidity.

Results

Overall, 18 deep-space infections (15 abscesses, 2 inflammatory infiltrations, 1 case of phlegmonous cellulitis), 2 mandibular fractures and 1 lingual nerve injury were noted within 1 year. The complications resulted from surgical procedures in 15 of the 21 cases, while in 6 they had their origin in pericoronitis. Extensive surgery or intensive care was required only for patients with postoperative complications. The length of stay in hospital was significantly greater for patients with postoperative complications (p= 0.007, U-test). However, 9 of these 15 patients reported preoperative episodes of infection. Thus, more than two thirds of the complications could be traced back to wisdom teeth that were causing symptoms.

Conclusion

In our clinic’s catchment area, infectious complications were more frequent and more severe and required more intensive and longer treatment in hospital than complications arising from pericoronitis. However, complications of prophylactic extraction of wisdom teeth were decidedly less frequent than direct or indirect complications of extraction of symptomatic teeth. Thus, our data tend to support the concept of elective extraction of wisdom teeth with the aim of preventing serious infections.     

Intravenous DDAVP and factor VIII-von Willebrand factor concentrate for the treatment and prophylaxis of bleedings in patients With von Willebrand disease type 1, 2 and 3.

The current standard set of von Willebrand factor (VWF) parameters used to differentiate type 1 from type 2 VWD include bleeding times (BTs), factor VIII coagulant activity (FVIII:C), VWF antigen (VWF:Ag), VWF ristocetine cofactor activity (VWF:RCo), VWF collagen binding activity (VWF:CB), ristocetine induced platelet aggregation (RIPA), and analysis of VWF multimers in low and high resolution agarose gels and the response to DDAVP. The BTs and RIPA are normal in asymptomatic carriers of a mutant VWF allele, in dominant type 1, and in recessive type 2N VWD, and this category has a normal response of VWF parameters to DDAVP. The response of FVIII:C is compromised in type 2N VWD. The BTs and RIPA are usually normal in type Vicenza and mild type 2A VWD, and these two VWD variants show a transiently good response of BT and VWF parameters followed by short in vivo half life times of VWF parameters. The BTS are strongly prolonged and RIPA typically absent in recessive severe type 1 and 3 VWD, in dominant type 2A and in recessive type 2C (very likely also 2D) VWD and consequently associated with low or absent platelet VWF, and no or poor response of VWF parameters to DDAVP. The BTs are prolonged and RIPA increased in dominant type 2B VWD, that is featured by normal platelet VWF and a poor response of BT and functional VWF to DDAVP. The BTs are prolonged and RIPA decreased in dominant type 2A and 2U, that all have low VWF platelet, very low VWF:RCo values as compared to VWF:Ag, and a poor response of functional VWF to DDAVP. VWD type 2M is featured by the presence of all VWF multimers in a low resolution agarose gel, normal or slightly prolonged BT, decreased RIPA, a poor response of VWF:RCo and a good response of FVIII and VWF:CB to DDAVP and therefore clearly in between dominant type 1 and 2U. The existing recommendations for prophylaxis and treatment of bleedings in type 2 VWD patients with FVIII/VWF concentrates are mainly derived from pharmocokinetic studies in type 3 VWD patients. FVIII/VWF concentrates should be characterised by labelling with FVIII:C, VWF:RCo, VWF:CB and VWF multimeric pattern to determine their safety and efficacy in prospective management studies. As the bleeding tendency is moderate in type 2 and severe in type 3 VWD and the FVIII:C levels are near normal in type 2 and very low in type 3 VWD patients. Proper recommendations of FVIII/VWF concentrates using VWF:RCo unit dosing for the prophylaxis and treatment of bleeding episodes are proposed and has to be stratified for the severity of bleeding, the type of surgery either minor or major and for type 2 and type 3 VWD as well.