Bruno Gagnon

Laval University, Quebec City, Quebec, Canada

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Publications (41)215.54 Total impact

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    ABSTRACT: Patient Generated Index (PGI) is designed to both ask and document quality of life (QOL) concerns. Its validity with respect to standard QOL measures has not been fully established for advanced cancer when QOL concerns predominate. The specific objective of this study is to identify, for people with advanced cancer, similarities and differences in ratings of global QOL between personalized and standard measures. A total of 192 patients completed five QOL measures at study entry: PGI, generic measures (SF-6D, EQ-5D), and cancer-specific measures of QOL (McGill Quality of Life Questionnaire and Edmonton Symptoms Assessment Scale). Comparisons among total scores were compared using Generalized Estimating Equations (GEE). Patients voiced 114 areas of QOL concerns by the PGI with the top three being fatigue, sleep, and pain (39.2, 22.6, and 21.6 %, respectively). PGI total QOL score was 25 to 30 percentage points lower than those documented by the other measures, particularly when QOL was poor. Correlations between PGI and other measures were low. PGI allowed patients to express a wide range of QOL concerns, many that were not assessed by other QOL measures. If only one QOL measure is to be included, either in a clinical setting or for research, the PGI would satisfy many of the criteria for "best choice." PGI could be considered a cancer-specific QOL measure. This study provides evidence that the PGI would be a good measure for patients and clinicians to use together to identify areas of concern that require attention and monitor changing needs.
    Supportive Care in Cancer 06/2015; DOI:10.1007/s00520-015-2821-7 · 2.50 Impact Factor
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    ABSTRACT: Cancer and cancer-related treatments are associated with a constellation of physical and psychological changes. Treatments associated with noncentral nervous system neoplasms can have short- and long-term effects on cognition, affecting quality of life in people with cancer. Clinical measurement tools specific to cancer-related mild cognitive impairment (MCI) are lacking. The Montreal Cognitive Assessment (MoCA) has been validated in a geriatric population and used in studies assessing MCI in persons with cancer, but no studies have yet shown its psychometric properties when used with this population. The purpose of this study is to explore the psychometric properties of the MoCA within a population of persons with noncentral nervous system cancer. A total of 74 participants were included from persons attending a Cancer Nutrition-Rehabilitation Program at the McGill University Health Centre. Rasch analyses were conducted. The MoCA data fit all the properties of the Rasch model with a person separation index of 1.04 and person reliability of 0.52. The MoCA items were found to measure a unidimensional construct and spanned 6.57 logits, with item difficulty levels between 2.49 and -4.08 logits. However, the MoCA presented a lack of items of higher difficulty, as person cognitive ability levels ranged from -0.51 to 5.17 logits. Within the limits of a small sample size, the results of this exploratory study suggest the possibility that the MoCA, when used within a population of persons with cancer, may meet criteria for unidimensionality and adequate item fit but may present weaknesses when used with participants of higher cognitive abilities.
    Supportive Care Cancer 02/2015; DOI:10.1007/s00520-015-2643-7 · 2.50 Impact Factor
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    ABSTRACT: In Canada, governments have increased spending on home care to promote better end-of-life care. In the province of Québec, Canada, home palliative care services (HPCS) are provided by Public Local Community-Based Health Care Service providers (Centres Locaux de Services Communautaires [CLSC]) with universal coverage. Accordingly, there should be no regional variations of these services and their effect on quality of end-of-life palliative care (QEoLPC) indicators. To test if all CLSCs provided the same level of HPCS to cancer patients in the province of Québec, and the association between level of HPCS and QEoLPC indicators. Characteristics of 52,316 decedents with cancer were extracted from administrative databases between 2003 and 2006. Two gender-specific "adjusted performance of CLSCs in delivering HPCS" models were created using gender-specific hierarchical regression adjusted for patient and CLSC neighborhood characteristics. Using the same approach, the strength of the association between the adjusted performance of CLSCs in delivering HPCS and the QEoLPC indicators was estimated. Overall, 27,255 (52.1%) decedents had at least one HPCS. Significant variations in the adjusted performance of CLSC in delivering HPCS were found. Higher performance led to a lower proportion of men having more than one emergency room visit during the last month of life (risk ratio [RR] 0.924; 95% CI 0.867-0.985), and for women, a higher proportion dying at home (RR 2.255; 95% CI 1.703-2.984) and spending less time in hospital (RR 0.765; 95% CI 0.692-0.845). Provision of HPCS remained limited in Québec, but when present, they were associated with improved QEoLPC indicators. Copyright © 2015 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
    Journal of Pain and Symptom Management 02/2015; DOI:10.1016/j.jpainsymman.2014.12.012 · 2.74 Impact Factor
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    ABSTRACT: Background Treatment with bisphosphonates in women with breast cancer and established bone metastasis delays further skeletal-related events. Evidence is emerging that bisphosphonates are beneficial for secondary prevention of bone metastasis. The study aimed to estimate the effect of oral bisphosphonates for treatment or prevention of osteoporosis on development of bone metastasis in a population of women with breast cancer. Methods A historical cohort of 21 664 women diagnosed with breast cancer was created from health administrative data in Quebec, Canada. The primary outcome was time to develop bone metastasis; exposure was bisphosphonate use prediagnosis, postdiagnosis, both, or neither and a cumulative index of drug exposure. The sample was stratified according to stage (0-II or III) at time of diagnosis. Cox proportional hazards tested the effect of bisphosphonate use on time to develop bone metastases. Results Taking bisphosphonates postdiagnosis of breast cancer only or continuing bisphosphonates started prior to diagnosis after diagnosis was associated with a reduction in risk of bone metastasis from 45% to 28% in women with local disease at diagnosis. In women with regional disease, postdiagnosis bisphosphonate use, with or without prediagnosis use, reduced risk by almost 50%. A statistically significant dose-response trend was observed relating increased use to lower risk (slope = 0.94, 95% confidence interval = 0.90 to 0.99). Bisphosphonates were also associated with a decreased risk of all-cause mortality similar to that of the development of bone metastasis. Conclusion Low-dose oral bisphosphonates administered for prevention or treatment of postmenopausal osteoporosis were associated with lower risk of skeletal metastasis in patients with early-or more advanced-stage breast cancer.
    JNCI Journal of the National Cancer Institute 11/2014; 106(11). DOI:10.1093/jnci/dju264 · 15.16 Impact Factor
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    ABSTRACT: Studies of opioid use in cancer patients have been cross-sectional or have focused on mean consumption over a specific time interval.
    Journal of Pain and Symptom Management 06/2014; 49(1). DOI:10.1016/j.jpainsymman.2014.05.015 · 2.74 Impact Factor
  • Value in Health 05/2014; 17(3):A192-A193. DOI:10.1016/j.jval.2014.03.1123 · 2.89 Impact Factor
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    ABSTRACT: Delirium occurs in patients across a wide array of health care settings. The extent to which formal management guidelines exist or are adaptable to palliative care is unclear. This review aims to 1) source published delirium management guidelines with potential relevance to palliative care settings, 2) discuss the process of guideline development, 3) appraise their clinical utility, and 4) outline the processes of their implementation and evaluation and make recommendations for future guideline development. We searched PubMed (1990-2013), Scopus, U.S. National Guideline Clearinghouse, Google, and relevant reference lists to identify published guidelines for the management of delirium. This was supplemented with multidisciplinary input from delirium researchers and other relevant stakeholders at an international delirium study planning meeting. There is a paucity of high-level evidence for pharmacological and non-pharmacological interventions in the management of delirium in palliative care. However, multiple delirium guidelines for clinical practice have been developed, with recommendations derived from "expert opinion" for areas where research evidence is lacking. In addition to their potential benefits, limitations of clinical guidelines warrant consideration. Guidelines should be appraised and then adapted for use in a particular setting before implementation. Further research is needed on the evaluation of guidelines, as disseminated and implemented in a clinical setting, focusing on measurable outcomes in addition to their impact on quality of care. Delirium clinical guidelines are available but the level of evidence is limited. More robust evidence is required for future guideline development.
    Journal of pain and symptom management 04/2014; DOI:10.1016/j.jpainsymman.2013.09.023 · 2.74 Impact Factor
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    ABSTRACT: Delirium often presents difficult management challenges in the context of goals of care in palliative care settings. To formulate an analytic framework for further research on delirium in palliative care settings, prioritize the associated research questions, discuss the inherent methodological challenges associated with relevant studies and outline the next steps in a program of delirium research. We combined multidisciplinary input from delirium researchers and knowledge users at an international delirium study planning meeting, relevant literature searches, focused input of epidemiological expertise, and a meeting participant and co-author survey to formulate a conceptual research framework and prioritize research questions. Our proposed framework incorporates three main groups of research questions: the first predominantly epidemiological, such as delirium occurrence rates, risk factor evaluation, screening and diagnosis; the second covers pragmatic management questions; the third relates to the development of predictive models for delirium outcomes. Based on aggregated survey responses to each research question or domain, the combined modal ratings of "very" or "extremely" important confirmed their priority. Using an analytic framework to represent the full clinical care pathway of delirium in palliative care settings, we identified multiple knowledge gaps in relation to the occurrence rates, assessment, management and outcome prediction of delirium in this population. The knowledge synthesis generated from adequately powered, multicentre studies to answer the framework's research questions will inform decision-making and policy development regarding delirium detection and management, and thus help to achieve better outcomes for patients in palliative care settings.
    Journal of pain and symptom management 04/2014; DOI:10.1016/j.jpainsymman.2013.12.245 · 2.74 Impact Factor
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    ABSTRACT: Delirium is a highly prevalent complication in patients in palliative care settings, especially in the end-of-life context. To review the current evidence base for treating episodes of delirium in palliative care settings and propose a framework for future development. We combined multidisciplinary input from delirium researchers and other purposely selected stakeholders at an international delirium study planning meeting. This was supplemented by a literature search of multiple databases and relevant reference lists to identify studies regarding therapeutic interventions for delirium. The context of delirium management in palliative care is highly variable. The standard management of a delirium episode includes the investigation of precipitating and aggravating factors followed by symptomatic treatment with drug therapy. However, the intensity of this management depends on illness trajectory and goals of care in addition to the local availability of both investigative modalities and therapeutic interventions. Pharmacologically, haloperidol remains the practice standard by consensus for symptomatic control. Dosing schedules are derived from expert opinion and various clinical practice guidelines as evidence-based data from palliative care settings are limited. The commonly used pharmacologic interventions for delirium in this population warrant evaluation in clinical trials to examine dosing and titration regimens, different routes of administration, and safety and efficacy compared with placebo. Delirium treatment is multidimensional and includes the identification of precipitating and aggravating factors. For symptomatic management, haloperidol remains the practice standard. Further high-quality collaborative research investigating the appropriate treatment of this complex syndrome is needed.
    Journal of pain and symptom management 01/2014; DOI:10.1016/j.jpainsymman.2013.07.018 · 2.74 Impact Factor
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    ABSTRACT: To determine the variability in processes of care in the last 6 months of life experienced by patients dying of primary intracranial tumors and potential predictors of place of death, a death-backwards cohort was assembled using historical data and 1,623 decedents were identified. 90 % of people had ≥1 admission to an acute care hospital and 23 % spent ≥3 months of their last 6 months of life in acute care. 44 % had ≥1 ER visits and 30 % were admitted ≥1 times to ICU. Only 18 % had a home visit by a physician. 10 % died at home but 49 % died in hospital, while 40 % died in a palliative care facility. Age, comorbidities, and being diagnosed with grade 4 astrocytoma were associated with greater burden of care. Level of care burden and age were associated with higher odds of dying in a treatment intensive place of death, being diagnosed with grade 4 astrocytoma had opposite effect. Despite valuable research efforts to improve the treatment of primary intracranial tumors that focus on biology, refinements to surgery, radiation, and chemotherapy, there is also room to improve aspects of care at the end of life situation. An integrative approach for this patients' population, from diagnosis to death, could potentially reduce the care burden in the final period on the health care system, patient's family and improve access to a better place of death.
    Journal of Neuro-Oncology 01/2014; 117(1). DOI:10.1007/s11060-014-1360-2 · 2.79 Impact Factor
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    ABSTRACT: Cancer can affect many dimensions of a patient's life, and in turn, it should be targeted using a multimodal approach. We tested the extent to which an interdisciplinary nutrition-rehabilitation program can improve the well-being of patients with advanced cancer. Between January 10, 2007, and September 29, 2010, 188 patients with advanced cancer enrolled in the 10-12-week program. Body weight, physical function, symptom severity, fatigue dimensions, distress level, coping ability, and overall quality of life were assessed at the start and end of the program. Of the enrolled patients, 70% completed the program. Patients experienced strong improvements in the physical and activity dimensions of fatigue (effect sizes: 0.8-1.1). They also experienced moderate reductions in the severity of weakness, depression, nervousness, shortness of breath, and distress (effect sizes: 0.5-0.7), and moderate improvements in Six Minute Walk Test distance, maximal gait speed, coping ability, and quality of life (effect sizes: 0.5-0.7) Furthermore, 77% of patients either maintained or increased their body weight. Interdisciplinary nutrition-rehabilitation can be advantageous for patients with advanced cancer and should be considered an integrated part of standard palliative care.
    Current Oncology 12/2013; 20(6):310-318. DOI:10.3747/co.20.1612 · 1.64 Impact Factor
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    ABSTRACT: Background: For evidence-based medical practice, well-defined risk scoring systems are essential to identify patients with a poor prognosis. The objective of this study was to develop a prognostic score, the Montreal prognostic score (MPS), to improve prognostication of patients with incurable non-small cell lung cancer (NSCLC) in everyday practice. Methods: A training cohort (TC) and a confirmatory cohort (CC) of newly diagnosed patients with NSCLC planning to receive chemotherapy were used to develop the MPS. Stage and clinically available biomarkers were entered into a Cox model and risk weights were estimated. C-statistics were used to test the accuracy. Results: The TC consisted of 258 patients and the CC consisted of 433 patients. Montreal prognostic score classified patients into three distinct groups with median survivals of 2.5 months (95% confidence interval (CI): 1.8, 4.2), 8.2 months (95% CI: 7.0, 9.4) and 18.2 months (95% CI: 14.0, 27.5), respectively (log-rank, P<0.001). Overall, the C-statistics were 0.691 (95% CI: 0.685, 0.697) for the TC and 0.665 (95% CI: 0.661, 0.670) for the CC. Conclusion: The MPS, by classifying patients into three well-defined prognostic groups, provides valuable information, which physicians could use to better inform their patients about treatment options, especially the best timing to involve palliative care teams.
    British Journal of Cancer 09/2013; 109(8). DOI:10.1038/bjc.2013.515 · 4.82 Impact Factor
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    ABSTRACT: Background:The definition of health for people with cancer is not focused solely on the physiology of illness and the length of life remaining, but is also concerned with improving the well-being and the quality of the life (QOL) remaining to be lived. This study aimed to identify the constructs most associated with QOL in people with advanced cancer.Methods:Two hundred three persons with recent diagnoses of different advanced cancers were evaluated with 65 variables representing individual and environmental factors, biological factors, symptoms, function, general health perceptions and overall QOL at diagnosis. Three independent stepwise multiple linear regressions identified the most important contributors to overall QOL. R(2) ranking and effect sizes were estimated and averaged by construct.Results:The most important contributor of overall QOL for people recently diagnosed with advanced cancer was social support. It was followed by general health perceptions, energy, social function, psychological function and physical function.Conclusions:We used effect sizes to summarise multiple multivariate linear regressions for a more manageable and clinically interpretable picture. The findings emphasise the importance of incorporating the assessment and treatment of relevant symptoms, functions and social support in people recently diagnosed with advanced cancer as part of their clinical care.British Journal of Cancer advance online publication 16 April 2013; doi:10.1038/bjc.2013.146 www.bjcancer.com.
    British Journal of Cancer 04/2013; DOI:10.1038/bjc.2013.146 · 4.82 Impact Factor
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    ABSTRACT: BACKGROUND: Patients with head and neck cancer experience complex posttreatment challenges. In a preliminary uncontrolled study, we evaluated the extent to which they can benefit from an interdisciplinary rehabilitation program. METHODS: Twenty-seven patients completed an 8-week nutrition-rehabilitation program. Six-minute walk distance (6MWD), body weight, symptom burden, distress, and quality of life were assessed at baseline and at the end of the program. RESULTS: Patients improved their mean 6MWD by 59 m (effect size = 0.8), and 78% of patients either maintained or increased their body weight. They also reported a clinically meaningful reduction in severity of insomnia, pain, weakness, anorexia, shortness of breath, depression and distress, and improvement in quality of life (effect sizes = 0.6-0.9). However, they reported no change in symptom interference with function. CONCLUSION: An interdisciplinary rehabilitation program may be beneficial to patients with head and neck cancer after treatment, but its effects should be evaluated in a controlled trial. © 2012 Wiley Periodicals, Inc. Head Neck, 2012.
    Head & Neck 03/2013; 35(3). DOI:10.1002/hed.22972 · 3.01 Impact Factor
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    ABSTRACT: CONTEXT: Low circulating testosterone concentrations are commonly observed in male patients with cancer and have been shown to be associated with weight loss and increased severity of many symptoms, including fatigue and weakness. OBJECTIVES: The aim of the present study was to determine the extent to which testosterone deficiency is associated with poor physical function in male patients with nonhormonal cancers. METHODS: We measured serum free testosterone concentration in 101 male patients with cancer evaluated at a nutrition-rehabilitation clinic and performed univariate and multivariate linear regression analyses to assess the effect of a free testosterone concentration in the lowest quartile on six-minute walk distance (6-MWD) (n=100) and maximal gait speed (n=49). RESULTS: In the univariate analyses, patients in the lowest free testosterone quartile had a 6-MWD that was 96m (95% CI 51-141) less and a maximal gait speed that was 0.26m/second (95% CI 0.06-0.47) slower on average than patients in the upper three free testosterone quartiles. When controlling for other demographic, clinical, and biological factors, a free testosterone concentration in the lowest quartile was associated, on average, with a 51m (95% CI 44-97) lower 6-MWD but did not affect maximal gait speed. CONCLUSION: The present study shows that in male patients with cancer, an extremely low serum free testosterone concentration is independently associated with 6-MWD but not maximal gait speed. Hence, a severe testosterone deficiency may impair their ability to perform sustained activity, but to a lesser degree, short bursts of activity.
    Journal of pain and symptom management 10/2012; 45(5). DOI:10.1016/j.jpainsymman.2012.05.010 · 2.74 Impact Factor
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    ABSTRACT: Delirium is a highly prevalent and deleterious disorder in terminally ill cancer patients. We assessed whether a multicomponent preventive intervention was effective in decreasing delirium incidence and severity among cancer patients receiving end-of-life care. A cohort of 1516 patients was followed from admission to death at seven Canadian palliative care centers. In two of these centers, routine care included a delirium preventive intervention targeting physicians (written notice on selective delirium risk factors and inquest on intended medication changes), patients, and their family (orientation to time and place, information about early delirium symptoms). Delirium frequency and severity were compared between patients at the intervention (N = 674) and usual-care (N = 842) centers based on thrice-daily symptom assessments with the Confusion Rating Scale. The overall rate of adherence to the intervention was 89.7%. The incidence of delirium was 49.1% in the intervention group, compared with 43.9% in the usual-care group (odds ratio [OR] 1.23, P = 0.045). When confounding variables were controlled for, no difference was observed between the intervention and the usual-care groups in delirium incidence (OR 0.94, P = 0.66), delirium severity (1.83 vs. 1.92; P = 0.07), total days in delirium (4.57 vs. 3.57 days; P = 0.63), or duration of first delirium episode (2.9 vs. 2.1 days; P = 0.96). Delirium-free survival was similar in the two groups. A simple multicomponent preventive intervention was ineffective in reducing delirium incidence or severity among cancer patients receiving end-of-life care. Delirium prevention remains a difficult challenge in terminally ill cancer patients.
    Psycho-Oncology 02/2012; 21(2):187-94. DOI:10.1002/pon.1881 · 4.04 Impact Factor
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    ABSTRACT: Delirium is the most frequent neuropsychiatric disorder that affects the advanced cancer population who are receiving palliative care. There is limited evidence and much debate about the role of hydration in delirium management at the end of life. The purpose of this article is to review the literature on delirium management with regards to pharmacological management and hydration. Pharmacological management is the first line of treatment for delirium, whereby antipsychotics are the medication of choice. However, they have not been approved by the United States Food and Drug Administration for delirium management as there is insufficient evidence supporting their use. Hydration is a believed to be a key component of delirium reversibility; yet there are conflicting results on its efficacy as an intervention for delirium management. As there are few studies of good methodological quality on the topic and large variations in practice, the effectiveness of hydration as an alternative management option for delirium is unclear. More work is required to assess the role of hydration in delirium at the end of life. Given the lack of evidence-based research on hydration, more randomized clinical trials are needed to elucidate the effects of hydration as a delirium intervention.
    Current opinion in supportive and palliative care 06/2011; 5(2):169-73. DOI:10.1097/SPC.0b013e3283462fdc
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    ABSTRACT: Several in vitro studies have indicated that metformin may reduce the risk of prostate cancer; however, epidemiologic studies have been inconclusive. The objective of this study was to determine whether metformin decreases the risk of prostate cancer in patients with type 2 diabetes. A nested case-control analysis was conducted within a population-based cohort from the UK General Practice Research Database. The cohort included patients over the age of 40 who were prescribed a first oral hypoglycemic agent (OHA) between 1988 and 2009. Cases of prostate cancer were matched up to ten controls on year of birth, date of cohort entry, and duration of follow-up. Adjusted rate ratios (RR) were estimated using conditional logistic regression. The cohort included 63,049 incident users of OHAs, in which 739 cases of prostate cancer were matched to 7,359 controls. Metformin use did not decrease the risk of prostate cancer (RR: 1.23, 95% CI: 0.99-1.52). In secondary analyses, prostate cancer risk was found to increase as a function of the number of metformin prescriptions received (one to seven prescriptions: RR: 1.05, 95% CI: 0.80-1.37; seven to eighteen prescriptions: RR: 1.29, 95% CI: 0.99-1.69; eighteen to thirty-six prescriptions: RR: 1.37, 95% CI: 1.04-1.81; more than thirty-six prescriptions: RR: 1.40, 95% CI: 1.03-1.89). The results of this study indicate that metformin does not reduce the risk of prostate cancer in patients with type 2 diabetes. The secondary analyses need to be interpreted with caution given the inverse association between type 2 diabetes and prostate cancer.
    Cancer Epidemiology Biomarkers & Prevention 03/2011; 20(2):337-44. DOI:10.1158/1055-9965.EPI-10-0940 · 4.32 Impact Factor
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    ABSTRACT: To review the research about psychostimulant effects on cognitive functions in end-of-life patients diagnosed with hypoactive delirium or cognitive disorders. The MEDLINE (1966-March 2008), Embase (1974-March 2008), PsycINFO (1806-March 2008), IPA (1970-March 2008), CINAHL (1982-March 2008), ISI Web of Science (1945-March 2008), Current Contents (March 2007-March 2008), Access Medicine (2001-March 2008), and ProQuest Dissertations & Theses (1980-March 2008) databases were searched with keywords related to delirium, cognition, psychostimulants, and palliative care for French or English articles in a dementia-free and hyperactive delirium-free end-of-life population. Cognitive functions had to be assessed before and after initiation of the psychostimulant treatment. Moreover, treatment had to be initiated after the onset of cognitive impairments. A total of 173 studies were screened. Five studies on methylphenidate and 1 study on caffeine met inclusion criteria and were included in this review. Two studies were case reports, 2 were open-label trials, and 2 were double-blind, crossover randomized placebo-controlled trials. Three studies were conducted with hypoactive delirium patients and all studies were conducted in an advanced cancer patient population. The reviewed studies support the use of methylphenidate to improve end-of-life patient cognitive functions, particularly in the case of hypoactive delirium. Caffeine seems to have beneficial effects on psychomotor activity. Further well-designed studies are needed to consolidate these findings.
    Canadian journal of psychiatry. Revue canadienne de psychiatrie 06/2010; 55(6):386-93. · 2.41 Impact Factor
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    ABSTRACT: C-reactive protein (CRP) is gaining credibility as a prognostic factor in different cancers. Cox's proportional hazard (PH) model is usually used to assess prognostic factors. However, this model imposes a priori assumptions, which are rarely tested, that (1) the hazard ratio associated with each prognostic factor remains constant across the follow-up (PH assumption) and (2) the relationship between a continuous predictor and the logarithm of the mortality hazard is linear (linearity assumption). We tested these two assumptions of the Cox's PH model for CRP, using a flexible statistical model, while adjusting for other known prognostic factors, in a cohort of 269 patients newly diagnosed with non-small cell lung cancer (NSCLC). In the Cox's PH model, high CRP increased the risk of death (HR=1.11 per each doubling of CRP value, 95% CI: 1.03-1.20, P=0.008). However, both the PH assumption (P=0.033) and the linearity assumption (P=0.015) were rejected for CRP, measured at the initiation of chemotherapy, which kept its prognostic value for approximately 18 months. Our analysis shows that flexible modeling provides new insights regarding the value of CRP as a prognostic factor in NSCLC and that Cox's PH model underestimates early risks associated with high CRP.
    British Journal of Cancer 03/2010; 102(7):1113-22. DOI:10.1038/sj.bjc.6605603 · 4.82 Impact Factor

Publication Stats

1k Citations
215.54 Total Impact Points

Institutions

  • 2013–2015
    • Laval University
      • Faculty of Medicine
      Quebec City, Quebec, Canada
  • 2003–2013
    • McGill University
      • • Faculty of Medicine
      • • Department of Medicine
      • • Department of Oncology
      Montréal, Quebec, Canada
  • 2001
    • Vrije Universiteit Brussel
      Bruxelles, Brussels Capital, Belgium
  • 1998
    • University of Alberta
      • Division of Palliative Care Medicine
      Edmonton, Alberta, Canada