Michel Vallée | Université de Montréal (original) (raw)

Papers by Michel Vallée

Clinical Journal of the American Society of Nephrology, 2012

Summary Background and objectives Peritonitis is a well known complication of peritoneal dialysis... more Summary Background and objectives Peritonitis is a well known complication of peritoneal dialysis (PD), whereas in hemodialysis (HD), bacteremia can be life threatening. Whether patients undergoing PD have higher risk than HD patients for infection-related hospitalizations (IRH) remains unknown. Design, setting, participants, & measurements A propensity score–matched retrospective cohort of patients undergoing long-term dialysis between January 2001 and December 2007 was assembled. Propensity scores were calculated using multivariable (demographic characteristics, smoking, body mass index, comorbid conditions, and laboratory data) logistic regression to estimate probability of receiving PD versus HD. A comparison of IRH risk by dialysis modality was estimated using a counting-process survival model. Results A total of 910 pairs of patients were matched by propensity scores. During a median follow-up of 2.1 years (interquartile range, 1.1–3.5 years), 341 patients were hospitalized on...

PloS one, 2016

The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Sever... more The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Several types of inflammatory cells and mediators have been found to be involved in the progression of chronic obstructive pulmonary disease (COPD). We sought to evaluate the association of the NLR with severity of airflow limitation and disease exacerbations in a COPD population. We analyzed 885 patients from the Korean COPD Subtype Study cohort that recruited subjects with COPD from 44 referral hospitals. We determined the relationship of NLR levels to severity of lung function using a linear regression model. In addition, we analyzed the experiences of COPD exacerbation according to the NLR quartiles. NLR levels were inversely associated with severity of airflow limitation as measured by FEV1% predicted and absolute values after adjustments for age, gender, body mass index, pack-years of smoking, and the use of inhaled corticosteroid (P<0.001, respectively). In the multivariate binary r...

Canadian Journal of Cardiology, 2016

Canadian Journal of Cardiology, 2012

See page 285 for disclosure information. A version of the hypertension recommendations designed f... more See page 285 for disclosure information. A version of the hypertension recommendations designed for patient and public education has been developed to assist health care practitioners managing hypertension. The summary is available electronically (go to http://www.hypertension.ca or http://www.heartandstroke.ca).

Canadian Journal of Cardiology, 2010

Practice 2010 Canadian Hypertension Education Program recommendations An annual update On behalf ... more Practice 2010 Canadian Hypertension Education Program recommendations An annual update On behalf of the Canadian Hypertension Education Program GO CFPlus *Tables 1 to 6, Boxes 1 to 3, and Figure 1 are available at www.cfp.ca. Go to the full text of this article online, then click on CFPlus in the menu at the top right-hand side of the page. This article is eligible for Mainpro-M1 credits. To earn credits, go to www.cfp.ca and click on the Mainpro link.

Canadian Journal of Cardiology, 2008

C ardiovascular disease (CVD) is the leading cause of death among Canadian women. Hypertension is... more C ardiovascular disease (CVD) is the leading cause of death among Canadian women. Hypertension is an established and prevalent risk factor for CVD, affecting more than one in five Canadian adults (1,2). In the Effect of Potentially Modifiable Risk Factors Associated with Myocardial Infarction in 52 Countries (INTERHEART) study (3), hypertension contributed to 29% of the population attributable risk for acute myocardial infarction in women compared with 15.9% with men, in part because the women were approximately one decade older. The prevalence of hypertension differs among men and women, as does the risk of CVD. Men develop clinically significant hypertension earlier, and among men 18 to 34 years of age, one in 10 are hypertensive compared with 2% of women; however, beyond 65 years of age, over 50% are hypertensive, and the prevalence of hypertension in women remains greater than in men (4). In addition to sex differences in epidemiology, there is evidence that there may be sex differences in the pathophysiology of hypertension. The renin-angiotensin system (RAS) plays a significant, if not central, role in the regulation of blood pressure (5,6). Endogenous sex hormones have been shown to interact with the RAS (Table 1). Androgens have been shown to upregulate the RAS and appear to produce an overall vasopressor effect (7). Estrogens, however, are in some way protective, with indirect evidence from an inverse relationship between the age of menopause and blood pressure (8). Also, the RAS is overall antagonized by estrogens (9). HYPERTENSION

International journal of general medicine, 2015

Thrombotic complications figure among the most frequent causes of mortality in diabetic ketoacido... more Thrombotic complications figure among the most frequent causes of mortality in diabetic ketoacidosis (DKA) and hyperosmolar state. We report the case of a 55-year-old woman presenting with DKA whereby a newly discovered patent foramen ovale was found due in part to the observation of bilateral deep vein thrombosis in legs, bilateral multiple pulmonary embolisms, and left subclavian acute artery thrombosis. Diabetes is known as a hypercoagulability state, and DKA is rising as a risk factor for vascular events. The importance of prophylactic anticoagulation should be emphasized in this setting.

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

Polyomavirus-associated nephropathy (PVAN) is an important cause of graft failure, affecting up t... more Polyomavirus-associated nephropathy (PVAN) is an important cause of graft failure, affecting up to 10% of renal transplant patients.1 Fifty percent of polyomavirus viremia occur in the first 3 months, and 95% in the first 2 years after transplant.1 In the early reports, up to 50% of viremia resulted in graft loss.2,3 Polymerase chain reaction (PCR) BK virus viremia is a sensitive and specific method to predict viral nephropathy,4 as it precedes PVAN by a median of 8 weeks.1 Systematic screening followed by preemptive reduction of immunosuppression is now widely recognized to prevent and treat PVAN.5-7 However, this strategy may increase the risk of acute graft rejection. The study was approved by the Ethical Review Committee of the Institute. All of the protocols conformed to the ethical guidelines of the 1975 Helsinki Declaration. Clinicians are now looking for drugs with antiviral activity allowing a decrease in viral replication without affecting the overall level of immuno suppr...

Population-based studies have shown that most patients with advanced chronic kidney disease (CKD)... more Population-based studies have shown that most patients with advanced chronic kidney disease (CKD) do not have optimal phosphate levels. Meta-analyses suggest that there is a morbidity and mortality benefit associated with the lowering of serum phosphate levels. However, to date there is no conclusive evidence from randomized controlled trials (RCTs) that lowering serum phosphate levels reduces the risk of morbidity and mortality. However, hyperphosphatemia may pose a risk to patients and treatment should be considered. We therefore sought to conduct a multidisciplinary review to help guide clinical decision-making pending results of ongoing RCTs. Restricting dietary phosphate intake is frequently the first step in the management of hyperphosphatemia. Important considerations when proposing dietary restriction include the patient’s socioeconomic status, lifestyle, dietary preferences, comorbidities, and nutritional status. While dietary phosphate restriction may be a valid strategy i...

In this report we examine the differences between the 2017 Hypertension Canada and 2017 American ... more In this report we examine the differences between the 2017 Hypertension Canada and 2017 American College of Cardiology and American Heart Association (ACC/AHA) blood pressure (BP) guidelines regarding the proportions of individuals with a diagnosis of hypertension, BP above thresholds for treatment initiation, and BP below targets using the CARTaGENE cohort. Compared with the 2017 Canadian guidelines, the 2017 ACC/AHA guidelines would result in increases of 8.7% in hypertension diagnosis and 3.4% of individuals needing treatment, with 17.2% having a different BP target. In conclusion, implementing the 2017 ACC/AHA hypertension guidelines in Canada could result in major effects for millions of Canadians.

Canadian Journal of Cardiology

Nephrology Dialysis Transplantation

American Journal of Kidney Diseases, 2010

Int. Journal of Clinical Pharmacology and Therapeutics

Canadian Journal of Diabetes

Int. Journal of Clinical Pharmacology and Therapeutics

Canadian journal of kidney health and disease, 2017

Neutrophil-to-lymphocyte ratio (NLR) was widely studied as a prognostic marker in various medical... more Neutrophil-to-lymphocyte ratio (NLR) was widely studied as a prognostic marker in various medical and surgical specialties, but its significance in nephrology is not yet established. We evaluated its accuracy as an inflammation biomarker in a dialysis population. Single-center retrospective study. The records of all 550 patients who were treated with hemodialysis (HD) or peritoneal dialysis (PD) from September 2008 to March 2011 were included. NLR was calculated from the monthly complete blood count. Association between NLR and markers of inflammation (C-reactive protein [CRP], serum albumin, and erythropoietin resistance index [ERI]) was measured using Spearman coefficient. In total, 120 patients were eligible for the correlation analyses. We found a positive correlation between NLR and CRP (all patients: = 0.45, < .001; HD: = 0.47, < .001; PD: = 0.48, = .13). NLR and albumin were inversely correlated ( = -0.51, < .001). Finally, high NLR was associated with a nonsignifica...

The Canadian journal of cardiology, 2018

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, asses... more Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children. This year, the adult and pediatric guidelines are combined in one document. The new 2018 pregnancy-specific hypertension guidelines are published separately. For 2018, 5 new guidelines are introduced, and 1 existing guideline on the blood pressure thresholds and targets in the setting of thrombolysis for acute ischemic stroke is revised. The use of validated wrist devices for the estimation of blood pressure in individuals with large arm circumference is now included. Guidance is provided for the follow-up measurements of blood pressure, with the use of standardized methods and electronic (oscillometric) upper arm devices in individuals with hypertension, and either ambulatory blood pressure monitoring or home blood pressure monitoring in individuals with white coat effect. We specify that all individuals with hyper...

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jan 21, 2016

Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-s... more Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-stage renal disease (ESRD) patients. Although a correlation has been established between ESAs and increased tumor growth among patients with cancer-related anemia, an association with a higher incidence of cancer among chronic dialysis patients remains relatively unclear. We completed a nested case-control study in a cohort of 4574 patients who began chronic dialysis treatment between 1 January 2001 and 31 December 2007 in Quebec, Canada, utilizing dialysis registry and administrative databases exclusively to extract our data. We excluded patients with a prior diagnosis of cancer. Eligible cases were identified by the time of initial cancer diagnosis obtained from either the hospital's discharge or physician billing form. We then randomly selected up to 10 controls for each case. ESA exposure was evaluated between 6 and 9 months prior to the initial cancer diagnosis. The mean weekly e...

Clinical Journal of the American Society of Nephrology, 2012

Summary Background and objectives Peritonitis is a well known complication of peritoneal dialysis... more Summary Background and objectives Peritonitis is a well known complication of peritoneal dialysis (PD), whereas in hemodialysis (HD), bacteremia can be life threatening. Whether patients undergoing PD have higher risk than HD patients for infection-related hospitalizations (IRH) remains unknown. Design, setting, participants, & measurements A propensity score–matched retrospective cohort of patients undergoing long-term dialysis between January 2001 and December 2007 was assembled. Propensity scores were calculated using multivariable (demographic characteristics, smoking, body mass index, comorbid conditions, and laboratory data) logistic regression to estimate probability of receiving PD versus HD. A comparison of IRH risk by dialysis modality was estimated using a counting-process survival model. Results A total of 910 pairs of patients were matched by propensity scores. During a median follow-up of 2.1 years (interquartile range, 1.1–3.5 years), 341 patients were hospitalized on...

PloS one, 2016

The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Sever... more The ratio of neutrophils to lymphocytes (NLR) is a widely available marker of inflammation. Several types of inflammatory cells and mediators have been found to be involved in the progression of chronic obstructive pulmonary disease (COPD). We sought to evaluate the association of the NLR with severity of airflow limitation and disease exacerbations in a COPD population. We analyzed 885 patients from the Korean COPD Subtype Study cohort that recruited subjects with COPD from 44 referral hospitals. We determined the relationship of NLR levels to severity of lung function using a linear regression model. In addition, we analyzed the experiences of COPD exacerbation according to the NLR quartiles. NLR levels were inversely associated with severity of airflow limitation as measured by FEV1% predicted and absolute values after adjustments for age, gender, body mass index, pack-years of smoking, and the use of inhaled corticosteroid (P<0.001, respectively). In the multivariate binary r...

Canadian Journal of Cardiology, 2016

Canadian Journal of Cardiology, 2012

See page 285 for disclosure information. A version of the hypertension recommendations designed f... more See page 285 for disclosure information. A version of the hypertension recommendations designed for patient and public education has been developed to assist health care practitioners managing hypertension. The summary is available electronically (go to http://www.hypertension.ca or http://www.heartandstroke.ca).

Canadian Journal of Cardiology, 2010

Practice 2010 Canadian Hypertension Education Program recommendations An annual update On behalf ... more Practice 2010 Canadian Hypertension Education Program recommendations An annual update On behalf of the Canadian Hypertension Education Program GO CFPlus *Tables 1 to 6, Boxes 1 to 3, and Figure 1 are available at www.cfp.ca. Go to the full text of this article online, then click on CFPlus in the menu at the top right-hand side of the page. This article is eligible for Mainpro-M1 credits. To earn credits, go to www.cfp.ca and click on the Mainpro link.

Canadian Journal of Cardiology, 2008

C ardiovascular disease (CVD) is the leading cause of death among Canadian women. Hypertension is... more C ardiovascular disease (CVD) is the leading cause of death among Canadian women. Hypertension is an established and prevalent risk factor for CVD, affecting more than one in five Canadian adults (1,2). In the Effect of Potentially Modifiable Risk Factors Associated with Myocardial Infarction in 52 Countries (INTERHEART) study (3), hypertension contributed to 29% of the population attributable risk for acute myocardial infarction in women compared with 15.9% with men, in part because the women were approximately one decade older. The prevalence of hypertension differs among men and women, as does the risk of CVD. Men develop clinically significant hypertension earlier, and among men 18 to 34 years of age, one in 10 are hypertensive compared with 2% of women; however, beyond 65 years of age, over 50% are hypertensive, and the prevalence of hypertension in women remains greater than in men (4). In addition to sex differences in epidemiology, there is evidence that there may be sex differences in the pathophysiology of hypertension. The renin-angiotensin system (RAS) plays a significant, if not central, role in the regulation of blood pressure (5,6). Endogenous sex hormones have been shown to interact with the RAS (Table 1). Androgens have been shown to upregulate the RAS and appear to produce an overall vasopressor effect (7). Estrogens, however, are in some way protective, with indirect evidence from an inverse relationship between the age of menopause and blood pressure (8). Also, the RAS is overall antagonized by estrogens (9). HYPERTENSION

International journal of general medicine, 2015

Thrombotic complications figure among the most frequent causes of mortality in diabetic ketoacido... more Thrombotic complications figure among the most frequent causes of mortality in diabetic ketoacidosis (DKA) and hyperosmolar state. We report the case of a 55-year-old woman presenting with DKA whereby a newly discovered patent foramen ovale was found due in part to the observation of bilateral deep vein thrombosis in legs, bilateral multiple pulmonary embolisms, and left subclavian acute artery thrombosis. Diabetes is known as a hypercoagulability state, and DKA is rising as a risk factor for vascular events. The importance of prophylactic anticoagulation should be emphasized in this setting.

Experimental and clinical transplantation : official journal of the Middle East Society for Organ Transplantation, 2015

Polyomavirus-associated nephropathy (PVAN) is an important cause of graft failure, affecting up t... more Polyomavirus-associated nephropathy (PVAN) is an important cause of graft failure, affecting up to 10% of renal transplant patients.1 Fifty percent of polyomavirus viremia occur in the first 3 months, and 95% in the first 2 years after transplant.1 In the early reports, up to 50% of viremia resulted in graft loss.2,3 Polymerase chain reaction (PCR) BK virus viremia is a sensitive and specific method to predict viral nephropathy,4 as it precedes PVAN by a median of 8 weeks.1 Systematic screening followed by preemptive reduction of immunosuppression is now widely recognized to prevent and treat PVAN.5-7 However, this strategy may increase the risk of acute graft rejection. The study was approved by the Ethical Review Committee of the Institute. All of the protocols conformed to the ethical guidelines of the 1975 Helsinki Declaration. Clinicians are now looking for drugs with antiviral activity allowing a decrease in viral replication without affecting the overall level of immuno suppr...

Population-based studies have shown that most patients with advanced chronic kidney disease (CKD)... more Population-based studies have shown that most patients with advanced chronic kidney disease (CKD) do not have optimal phosphate levels. Meta-analyses suggest that there is a morbidity and mortality benefit associated with the lowering of serum phosphate levels. However, to date there is no conclusive evidence from randomized controlled trials (RCTs) that lowering serum phosphate levels reduces the risk of morbidity and mortality. However, hyperphosphatemia may pose a risk to patients and treatment should be considered. We therefore sought to conduct a multidisciplinary review to help guide clinical decision-making pending results of ongoing RCTs. Restricting dietary phosphate intake is frequently the first step in the management of hyperphosphatemia. Important considerations when proposing dietary restriction include the patient’s socioeconomic status, lifestyle, dietary preferences, comorbidities, and nutritional status. While dietary phosphate restriction may be a valid strategy i...

In this report we examine the differences between the 2017 Hypertension Canada and 2017 American ... more In this report we examine the differences between the 2017 Hypertension Canada and 2017 American College of Cardiology and American Heart Association (ACC/AHA) blood pressure (BP) guidelines regarding the proportions of individuals with a diagnosis of hypertension, BP above thresholds for treatment initiation, and BP below targets using the CARTaGENE cohort. Compared with the 2017 Canadian guidelines, the 2017 ACC/AHA guidelines would result in increases of 8.7% in hypertension diagnosis and 3.4% of individuals needing treatment, with 17.2% having a different BP target. In conclusion, implementing the 2017 ACC/AHA hypertension guidelines in Canada could result in major effects for millions of Canadians.

Canadian Journal of Cardiology

Nephrology Dialysis Transplantation

American Journal of Kidney Diseases, 2010

Int. Journal of Clinical Pharmacology and Therapeutics

Canadian Journal of Diabetes

Int. Journal of Clinical Pharmacology and Therapeutics

Canadian journal of kidney health and disease, 2017

Neutrophil-to-lymphocyte ratio (NLR) was widely studied as a prognostic marker in various medical... more Neutrophil-to-lymphocyte ratio (NLR) was widely studied as a prognostic marker in various medical and surgical specialties, but its significance in nephrology is not yet established. We evaluated its accuracy as an inflammation biomarker in a dialysis population. Single-center retrospective study. The records of all 550 patients who were treated with hemodialysis (HD) or peritoneal dialysis (PD) from September 2008 to March 2011 were included. NLR was calculated from the monthly complete blood count. Association between NLR and markers of inflammation (C-reactive protein [CRP], serum albumin, and erythropoietin resistance index [ERI]) was measured using Spearman coefficient. In total, 120 patients were eligible for the correlation analyses. We found a positive correlation between NLR and CRP (all patients: = 0.45, < .001; HD: = 0.47, < .001; PD: = 0.48, = .13). NLR and albumin were inversely correlated ( = -0.51, < .001). Finally, high NLR was associated with a nonsignifica...

The Canadian journal of cardiology, 2018

Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, asses... more Hypertension Canada provides annually updated, evidence-based guidelines for the diagnosis, assessment, prevention, and treatment of hypertension in adults and children. This year, the adult and pediatric guidelines are combined in one document. The new 2018 pregnancy-specific hypertension guidelines are published separately. For 2018, 5 new guidelines are introduced, and 1 existing guideline on the blood pressure thresholds and targets in the setting of thrombolysis for acute ischemic stroke is revised. The use of validated wrist devices for the estimation of blood pressure in individuals with large arm circumference is now included. Guidance is provided for the follow-up measurements of blood pressure, with the use of standardized methods and electronic (oscillometric) upper arm devices in individuals with hypertension, and either ambulatory blood pressure monitoring or home blood pressure monitoring in individuals with white coat effect. We specify that all individuals with hyper...

Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association, Jan 21, 2016

Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-s... more Erythropoiesis-stimulating agents (ESAs) are the cornerstone of the treatment for anemia in end-stage renal disease (ESRD) patients. Although a correlation has been established between ESAs and increased tumor growth among patients with cancer-related anemia, an association with a higher incidence of cancer among chronic dialysis patients remains relatively unclear. We completed a nested case-control study in a cohort of 4574 patients who began chronic dialysis treatment between 1 January 2001 and 31 December 2007 in Quebec, Canada, utilizing dialysis registry and administrative databases exclusively to extract our data. We excluded patients with a prior diagnosis of cancer. Eligible cases were identified by the time of initial cancer diagnosis obtained from either the hospital's discharge or physician billing form. We then randomly selected up to 10 controls for each case. ESA exposure was evaluated between 6 and 9 months prior to the initial cancer diagnosis. The mean weekly e...