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Abstract Many studies have projected malaria risks with climate change scenarios by modelling one or two environmental variables and without the consideration of malaria control interventions. We aimed to predict the risk of malaria with climate change considering the influence of rainfall, humidity, temperatures, vegetation, and vector control interventions (indoor residual spraying (IRS) and long-lasting insecticidal nets (LLIN)). We used negative binomial models based on weekly malaria data from six facility-based surveillance sites in Uganda from 2010–2018, to estimate associations between malaria, environmental variables and interventions, accounting for the non-linearity of environmental variables. Associations were applied to future climate scenarios to predict malaria distribution using an ensemble of Regional Climate Models under two Representative Concentration Pathways (RCP4.5 and RCP8.5). Predictions including interaction effects between environmental variables and interventions were also explored. The results showed upward trends in the annual malaria cases by 25% to 30% by 2050s in the absence of intervention but there was great variability in the predictions (historical vs RCP 4.5 medians [Min–Max]: 16,785 [9,902–74,382] vs 21,289 [11,796–70,606]). The combination of IRS and LLIN, IRS alone, and LLIN alone would contribute to reducing the malaria burden by 76%, 63% and 35% respectively. Similar conclusions were drawn from the predictions of the models with and without interactions between environmental factors and interventions, suggesting that the interactions have no added value for the predictions. The results highlight the need for maintaining vector control interventions for malaria prevention and control in the context of climate change given the potential public health and economic implications of increasing malaria in Uganda.

Abstract Studies have estimated the impact of the environment on malaria incidence although few have explored the differential impact due to malaria control interventions. Therefore, the objective of the study was to evaluate the effect of indoor residual spraying (IRS) on the relationship between malaria and environment (i.e. rainfall, temperatures, humidity, and vegetation) using data from a dynamic cohort of children from three sub-counties in Uganda. Environmental variables were extracted from remote sensing sources and averaged over different time periods. General linear mixed models were constructed for each sub-counties based on a log-binomial distribution. The influence of IRS was analysed by comparing marginal effects of environment in models adjusted and unadjusted for IRS. Great regional variability in the shape (linear and non-linear), direction, and magnitude of environmental associations with malaria risk were observed between sub-counties. IRS was significantly associated with malaria risk reduction (risk ratios vary from RR = 0.03, CI 95% [0.03–0.08] to RR = 0.35, CI95% [0.28–0.42]). Model adjustment for this intervention changed the magnitude and/or direction of environment-malaria associations, suggesting an interaction effect. This study evaluated the potential influence of IRS in the malaria-environment association and highlighted the necessity to control for interventions when they are performed to properly estimate the environmental influence on malaria. Local models are more informative to guide intervention program compared to national models.

Background: Noise has been related to several cardiovascular diseases (CVDs) such as coronary heart disease and to their risk factors such as hypertension, but associations with stroke remain under-researched, even if CVD likely share similar pathophysiologic mechanisms. Aim: The objective of the study was to examine the association between long-term residential exposure to total environmental noise and stroke incidence in Montreal, Canada. Materials and Methods: We created an open cohort of adults aged ≥45years, free of stroke before entering the cohort for the years 2000 to 2014 with health administrative data. Residential total environmental noise levels were estimated with land use regression (LUR) models. Incident stroke was based on hospital admissions. Cox hazard models with age as the time axis and time-varying exposures were used to estimate associations, which were adjusted for material deprivation, year, nitrogen dioxide, stratified for sex, and indirectly adjusted for smoking. Results: There were 9,072,492 person-years of follow-up with 47% men; 26,741 developed stroke (21,402 ischemic; 4947 hemorrhagic; 392 had both). LUR total noise level acoustic equivalent for 24 hours (LAeq24h) ranged 44 to 79 dBA. The adjusted hazard ratio (HR) for stroke (all types), for a 10-dBA increase in LAeq24h, was 1.06 [95% confidence interval (CI): 1.03–1.09]. The LAeq24h was associated with ischemic (HR per 10 dBA: 1.08; 95% CI: 1.04–1.12) but not hemorrhagic stroke (HR per 10 dBA: 0.97; 95% CI: 0.90–1.04). Conclusion: The results suggest that total environmental noise is associated with incident stroke, which is consistent with studies on transportation noise and other CVD.

Background: Studies of the association between air pollution and asthma onset have mostly focused on urban and traffic-related air pollution. We investigated the associations between exposure to industrial emissions and childhood-onset asthma in a population-based birth cohort in Quebec, Canada, 2002–2011. Methods: The cohort was built from administrative health databases. We developed separately for PM2.5 and SO2 different metrics representing children's time-varying residential exposure to industrial emissions: 1) yearly number of tons of air pollutant emitted by industries located within 2.5 km of the residence; 2) distance to the nearest “major emitter” (≥100 tons) of either PM2.5 and SO2 within 7.5 km of the residence, and; 3) tons of air pollutant emitted by the nearest “major emitter” within 7.5 km, weighted by the inverse of the distance and the percentage of time that the residence was downwind. To handle the large number of zeros (i.e., children unexposed) we decomposed the exposure variable into two covariates simultaneously included in the regression model: a binary indicator of exposure and a continuous exposure variable centered at the mean value among exposed children. We performed Cox models using age as the time axis, adjusted for gender, material and social deprivation and calendar year. We indirectly adjusted for unmeasured secondhand smoke. Results: The cohort included 722,667 children and 66,559 incident cases of asthma. Across the different exposure metrics, mean percentage changes in the risk of asthma onset in children exposed to the mean relative to those unexposed ranged from 4.5% (95% CI: 2.8, 6.3%) to 10.6% (95% CI: 6.2, 15.2%) for PM2.5 and, from 1.1% (95% CI: −0.1, 3.3%) to 8.9% (95% CI: 7.1, 11.1%) for SO2. Indirect adjustment for secondhand smoke did not substantially affect the associations. In children exposed, the risk of asthma onset increased with the magnitude of the exposure for all metrics, except the distance to the nearest major emitter of SO2. Conclusions: In this population-based birth cohort, residential exposure to industrial air pollutant emissions was associated with childhood-onset asthma. Additional studies with improved models for estimating exposure to industrial point-sources are needed to further support the observed associations. Keywords: Air pollution, Cohort study, Asthma, Industry, Children, Fine particles, Sulfur dioxide

Introduction: In 2011, the Agence de la santé et des services sociaux de Montréal (ASSSM), in partnership with the region’s Centres de santé et de services sociaux (CSSS), coordinated the implementation of a program on cardiometabolic risk based on the Chronic Care Model. The program, intended for patients suffering from diabetes or hypertension, involved a series of individual follow-up appointments, group classes and exercise sessions. Our study assesses the impact on patient health outcomes of variations in the implementation of some aspects of the program among the six CSSSs taking part in the study. Methods: The evaluation was carried out using a quasi-experimental “before and after” design. Implementation variables were constructed based on data collected during the implementation analysis regarding resources, compliance with the clinical process set out in the regional program, the program experience and internal coordination within the care team. Differences in differences using propensity scores were calculated for HbA1c results, achieving the blood pressure (BP) target, and two lifestyle targets (exercise level and carbohydrate distribution) at the 6- and 12-month follow-ups, based on greater or lesser patient exposure to the implementation of various aspects of the program under study. Results: The results focus on 1185 patients for whom we had data at the 6-month follow- up and the 992 patients from the 12-month follow-up. The difference in differences analysis shows no clear association between the extent of implementation of the various aspects of the program under study and patient health outcomes. Conclusion: The program produces effects on selected health indicators independent of variations in program implementation among the CSSSs taking part in the study. The results suggest that the effects of this type of program are more highly dependent on the delivery of interventions to patients than on the organizational aspects of its implementation.

Introduction : En 2011, l’Agence de la santé et des services sociaux de Montréal (ASSSM), en partenariat avec les Centres de santé et de services sociaux (CSSS) de la région, a coordonné la mise en oeuvre d’un programme sur le risque cardiométabolique s’inspirant du Chronic Care Model. Ce programme destiné aux patients diabétiques ou hypertendus comporte une séquence de suivis individuels, des cours de groupe et des séances d’activité physique. Notre étude évalue l’impact de la variation dans l’implantation de certains aspects du programme entre les six CSSS participant à l’étude sur les résultats de santé des patients. Méthodologie : L’évaluation a été réalisée à l’aide d’un devis quasi-expérimental « avantaprès ». Des variables d’implantation ont été construites à partir de données colligées lors de l’analyse d’implantation concernant les ressources, la conformité au processus clinique prévu dans le programme régional, l’expérience du programme et la coordination interne au sein de l’équipe de soins. Des différences de différences utilisant des scores de propension ont été calculées pour les résultats d’HbA1c, l’atteinte de la cible de tension artérielle (TA) et de deux cibles d’habitudes de vie (niveau d’activité physique et répartition des glucides alimentaires) à 6 mois et à 12 mois de suivi, en fonction de l’exposition des patients à un degré plus ou moins important d’implantation de divers aspects du programme à l’étude. Résultats : Les résultats portent sur les 1 185 patients pour lesquels on disposait de données de suivi à 6 mois et les 992 patients pour le suivi à 12 mois. Les analyses de différences de différences ne révèlent aucune association claire entre le degré d’implantation des divers aspects du programme à l’étude et les résultats de santé chez les patients. Conclusion : Le programme produit des effets sur les indicateurs de santé sélectionnés indépendamment des variations dans l’implantation du programme entre les CSSS participant à l’étude. Les résultats suggèrent que les effets d’un tel programme sont davantage tributaires de la prestation des interventions auprès des patients que des aspects organisationnels liés à son implantation.

Introduction: Chronic disease management requires substantial services integration. A cardiometabolic risk management program inspired by the Chronic Care Model was implemented in Montréal for patients with diabetes or hypertension. One of this study's objectives was to assess the impact of care coordination between the interdisciplinary teams and physicians on patient participation in the program, lifestyle improvements and disease control. Methods: We obtained data on health outcomes from a register of clinical data, questionnaires completed by patients upon entry into the program and at the 12-month mark, and we drew information on the program's characteristics from the implementation analysis. We conducted multiple regression analyses, controlling for patient sociodemographic and health characteristics to measure the association between interdisciplinary team coordination with primary care physicians and various health outcomes. Results: A total of 1689 patients took part in the study (60.1% participation rate). Approximately 40% of patients withdrew from the program during the first year. At the 12-month follow-up (n = 992), we observed a significant increase in the proportion of patients achieving the various clinical targets. The perception by the interdisciplinary team of greater care coordination with primary care physicians was associated with increased participation in the program and the achievement of better clinical results. Conclusion: Greater coordination of patient services between interdisciplinary teams and primary care physicians translates into benefits for patients.

Introduction : La gestion des maladies chroniques nécessite une grande intégration des services. Un programme de gestion du risque cardiométabolique inspiré du Chronic Care Model a été implanté à Montréal pour les patients atteints de diabète ou d'hypertension. Un des objectifs de notre étude était d'apprécier l'impact de la coordination des soins entre les équipes interdisciplinaires et les médecins sur la participation des patients au programme et sur l'amélioration des habitudes de vie et le contrôle de la maladie. Méthodologie : Nous avons utilisé des données sur les résultats de santé issues d'un registre de données cliniques et de questionnaires aux patients à leur entrée dans le programme et à 12 mois de suivi, ainsi que des données sur les caractéristiques du programme provenant de l'analyse de son implantation. Nous avons réalisé des analyses de régression multiple, contrôlant pour les caractéristiques sociodémographiques et de santé des patients, pour mesurer l'association entre la coordination de l'équipe interdisciplinaire avec les médecins de première ligne et différents résultats de santé. Résultats : Au total, 1689 patients ont participé à l'évaluation (taux de participation 60,1 %). Environ 40 % des patients ont abandonné le programme durant la première année. À 12 mois de suivi (n = 992), nous avons observé une augmentation significative de la proportion des patients atteignant les différentes cibles cliniques. La perception par l'équipe interdisciplinaire d'une meilleure coordination des soins avec les médecins de première ligne était associée à une plus grande participation des patients au programme et à l'atteinte de meilleurs résultats cliniques. Conclusion : Une plus grande coordination des services aux patients entre des équipes interdisciplinaires et les médecins de première ligne se traduit par des effets bénéfiques chez les patients.

Physicians’ gender can have an impact on many aspects of patient experience of care. Organization processes through which the influence of gender is exerted have not been fully explored. The aim of this article is to compare primary health care (PHC) organizations in which female or male doctors are predominant regarding organization and patient characteristics, and to assess their influence on experience of care, preventive care delivery, use of services, and unmet needs. In 2010, we conducted surveys of a population stratified sample (N = 9180) and of all PHC organizations (N = 606) in 2 regions of the province of Québec, Canada. Patient and organization variables were entered sequentially into multilevel regression analyses to measure the impact of gender predominance. Female-predominant organizations had younger doctors and nurses with more expanded role; they collaborated more with other PHC practices, used more tools for prevention, and allotted more time to patient visits. However, doctors spent fewer hours a week at the practice in female-predominant organizations. Patients of these organizations reported lower accessibility. Conversely, they reported better comprehensiveness, responsiveness, counseling, and screening, but these effects were mainly attributable to doctors’ younger age. Their reporting unmet needs and emergency department attendance tended to decrease when controlling for patient and organization variables other than doctors’ age. Except for accessibility, female-predominant PHC organizations are comparable with their male counterparts. Mean age of doctors was an important confounding variable that mitigated differences, whereas other organization variables enhanced them. These findings deserve consideration to better understand and assess the impacts of the growing number of female-predominant PHC organizations on the health care system.

The determination of changes in gene expression profiles with xenobiotic dose will allow identifying biomarkers and modes of toxicant action. The harbor seal (Phoca vitulina) 11B7501 B lymphoma cell line was exposed to 1, 10, 100, 1000, 10,000, or 25,000 μg/L 17α-ethinyl estradiol (EE2, the active compound of the contraceptive pill) for 24 h. Following exposure, RNA was extracted and transformed into cDNA. Transcript expression in exposed vs. control lymphocytes was analyzed via RT-qPCR to identify genes with altered expression. Our analysis indicates that gene expression for all but the reference gene varied with dose, suggesting that different doses induce distinct physiological responses. These findings demonstrate that RT-qPCR could be used to identify immunotoxicity and relative dose in harbor seal leukocytes.

The blue mussel is a filter-feeding bivalve commonly used in ecotoxicological monitoring as a sentinel species. Due to climate change and the increase of temperature expected in marine environment, it is important to anticipate potential impacts on this species. The aim of this study was to investigate the immunocompetence of blue mussels acclimated to different temperatures and on the effects of increasing temperatures (5, 10 and 20°C). Different indices and gonad maturation stages were also determined throughout the experiments. Cell viability, phagocytosis, serum lysozyme activity and cyclooxygenase (COX) activity were evaluated as immune parameters. The cellular immunity was also evaluated after hemocytes exposure to various cadmium concentrations in vitro. The results obtained demonstrate modulation of hemocyte viability and the ability of these cells to phagocytize in absence of contaminants. After the exposure to cadmium, hemocytes showed greater viability at 5°C while maintaining a higher phagocytic competence. In addition, the lysozyme activity stayed stable at all tested temperatures, contrary to that of COX, which increased when the mussels were maintained at 20°C. The evaluation of indices demonstrated no reduction of general conditions during all the experiment despite the increase of temperature and the reduction of the digestive gland weight. Moreover, the lack of food does not affect gonad maturation and the spawning process.

Carbon nanomaterials are present in various industrial applications and therefore their release into the environment including freshwater ecosystem is expected to increase. The aim of the present study was to investigate the influence of several parameters on the toxicity of single-walled carbon nanotubes (SWCNT) to the freshwater amphipod, Hyalella azteca. The effect of period of exposure, sediment presence and possible impurities released during SWCNT preparation on survival and/or growth of such organism was evaluated. We measured a reduction of survival at concentrations ranging from 10 to 40 mg/L after 96-h exposure, while no mortality was observed with the same concentrations and in the presence of artificial sediment after 14 days of exposure. It is possible that SWCNT are adsorbed on the organic matter from the artificial sediment leading to a decrease of SWCNT bioavailability. The survival and growth toxicity tests revealed a stronger effect at 28 days compared to the 14 days of exposure, and full mortality of organisms at 1000 mg/L for both exposure times. The presence of SWCNT in the gut of survived organisms was observed. The present study demonstrates that the interaction with sediment should be considered when carbon nanotubes toxicity through water exposure is investigated.

The spill of liquid industrial waste from chemical and petrochemical industries in Mercier lagoons located 20 km south of Montreal, Quebec, caused a major groundwater contamination by industrial contaminants. The aim of this study was to investigate the toxic effects of Mercier groundwater, following 4 and 14 days of exposure to graded concentrations from three wells at increasing distances 1.2, 2.7 and 5.4 km from the source of contamination. Rainbow trout were examined for several biomarkers of defense [ethoxyresorufin O-deethylase (EROD) and gluthatione S-transferase (GST) activities] and those of tissue damage [lipid peroxidation (LPO) and DNA strand breaks]. The results showed that EROD activity was significantly enhanced in hepatic tissue at 1.2 and 5.4 km, whereas inhibition in activity was observed in group at 2.7 km. Therefore, GST activity was significantly increased at 3.1% concentration for the 2.7 km well. No change in LPO was observed. However, a significant induction of DNA strand breaks in liver was obtained at each distance. In conclusion, the data suggest that the release of these contaminants in groundwater leads to increased biotransformation for coplanar aromatic hydrocarbons and DNA damage in groundwater.

Breathing is maintained and controlled by a network of automatic neurons in the brainstem that generate respiratory rhythm and receive regulatory inputs. Breathing complexity therefore arises from respiratory central pattern generators modulated by peripheral and supra-spinal inputs. Very little is known on the brainstem neural substrates underlying breathing complexity in humans. We used both experimental and theoretical approaches to decipher these mechanisms in healthy humans and patients with chronic obstructive pulmonary disease (COPD). COPD is the most frequent chronic lung disease in the general population mainly due to tobacco smoke. In patients, airflow obstruction associated with hyperinflation and respiratory muscles weakness are key factors contributing to load-capacity imbalance and hence increased respiratory drive. Unexpectedly, we found that the patients breathed with a higher level of complexity during inspiration and expiration than controls. Using functional magnetic resonance imaging (fMRI), we scanned the brain of the participants to analyze the activity of two small regions involved in respiratory rhythmogenesis, the rostral ventro-lateral (VL) medulla (pre-Bötzinger complex) and the caudal VL pons (parafacial group). fMRI revealed in controls higher activity of the VL medulla suggesting active inspiration, while in patients higher activity of the VL pons suggesting active expiration. COPD patients reactivate the parafacial to sustain ventilation. These findings may be involved in the onset of respiratory failure when the neural network becomes overwhelmed by respiratory overload We show that central neural activity correlates with airflow complexity in healthy subjects and COPD patients, at rest and during inspiratory loading. We finally used a theoretical approach of respiratory rhythmogenesis that reproduces the kernel activity of neurons involved in the automatic breathing. The model reveals how a chaotic activity in neurons can contribute to chaos in airflow and reproduces key experimental fMRI findings.

In this study, we assessed in vitro the effects of PCDD/Fs on the NK-like cell activity in Eisenia andrei earthworms using flow cytometry for analysis. NK-like coelomocytes isolated from E. andrei and used as effectors were exposed to various concentrations of PCDDs/Fs mixture, C1 (6.25x10-3 ng 2378- TCDD/mL), C2 (12.5x10-3 ng 2378-TCDD/mL) and C3 (25x10-3 ng 2378-TCDD/mL), before adding them to human tumoral cells (K562) used as targets. We evaluated the percentage of targets lysed by Nk-like cells. The results showed a significant stimulation of the NKlike activity at C3 when PCDD/Fs were not removed from effectors before contact with targets, while no effects were noted when the effectors were washed (PCDD/Fs removed) or fixed. Assessment of the viability of the targets (K562), exposed alone and separately from effectors, to the three concentrations of PCDD/Fs, C1, C2 and C3, showed that all these concentrations were cytotoxic for K562. Results suggest that PCDD/Fs concentrations tested in this assay may be considered too low to induce suppressive effects on the immune function such as the NK-like activity in E. andrei earthworms.

The immunotoxicological effects of polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDDs/Fs) mixtures on Eisenia andrei earthworms have never been studied. In this work we investigated these effects both for in vitro and in vivo exposure, using the viability and the phagocytic activity of coelomocytes as immunological biomarkers and the flow cytometry was used for analysis. The in vitro exposure revealed a cytotoxic effect of PCDD/Fs mixture (C2) containing 50¥10-3 ng/mL of 2, 3, 7, 8-TCDD and an induction of the phagocytic capacity at the mixture (C1) containing 25¥10-3 ng/mL of 2, 3, 7, 8-TCDD. In the in vivo filter paper exposure, the immunocompetence of earthworms was assessed after 3 h-exposure to mixtures of PCDD/Fs at the levels of C1, C2, C3 and C4 containing about; 0.05, 0.3, 0.5 and 0.83 ng of 2, 3, 7, 8-TCDD/cm², respectively. Morphological observations showed an excessive secretion of mucus and body surface lesions in worms exposed to higher concentrations (C3 and C4), which revealed that these organisms were affected by PCDD/Fs either through skin and/or by feeding. The levels of the extruded cell yield decreased significantly at all the concentrations tested. However, the cell viability was shown to be unaffected by PCDD/Fs concentrations. It was also shown, that exposure to the highest PCDD/Fs concentrations; C2, C3 and C4 inhibited both phagocytic activity and efficiency.

As a general rule, almost all of Quebec’s workers who suffer work injuries will be taken care of by the worker compensation system. However, access to worker compensation is difficult for many workers, including immigrant workers. This article describes the evaluation process and the criteria used for assessing the difficulties encountered by workers during the compensation process. Three groups of experts assigned difficulty scores to a sample group from the Montreal region consisting of 104 immigrant and non-immigrant musculoskeletal injury victims. The difficulty scores were compared using three aspects for evaluation (medical, legal and administrative), which produced the same result: the immigrant workers had higher difficulty scores than the other workers and particularly from the legal and administrative standpoints. The criteria used targeted the human dimensions associated with the lack of understanding during the process and with communication problems in reading documents, completing forms and verbally describing precisely the accident events, the injury circumstances and the medical symptoms.

Cet article propose une réflexion sur la modélisation statistique des scores aux tests. Il s’interroge sur les différences réelles qui existent entre la « Théorie classique des tests » et la « Théorie de la réponse à l’item ». Il avance que ces deux approches sont utiles pour prédire et classer des candidats qui subissent des tests en grands groupes, mais très peu utiles pour le diagnostic pédagogique. Il termine en suggérant que de nouvelles perspectives s’ouvrent aux praticiens. Ces perspectives s’intéressent principalement aux processus et puisent leur inspiration dans le développement concerté des théories des tests et de la psychologie cognitive.