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Featured researches published by John R. Walker.


Journal of Psychosomatic Research | 2017

Increased incidence of psychiatric disorders in immune-mediated inflammatory disease

Ruth Ann Marrie; Randy Walld; James M. Bolton; Jitender Sareen; John R. Walker; Scott B. Patten; Alexander Singer; Lisa M. Lix; Carol A. Hitchon; Renée El-Gabalawy; Alan Katz; John D. Fisk; Charles N. Bernstein

OBJECTIVEnAlthough psychiatric comorbidity is known to be more prevalent in immune-mediated inflammatory diseases (IMID) than in the general population, the incidence of psychiatric comorbidity in IMID is less understood, yet incidence is more relevant for understanding etiology.nnnMETHODSnUsing population-based administrative (health) data, we conducted a retrospective cohort study over the period 1989-2012 in Manitoba, Canada. We identified 19,572 incident cases of IMID including 6119 persons with inflammatory bowel disease (IBD), 3514 persons with multiple sclerosis (MS), 10,206 persons with rheumatoid arthritis (RA), and 97,727 age-, sex- and geographically-matched controls. After applying validated case definitions, we estimated the incidence of depression, anxiety disorder, bipolar disorder and schizophrenia in each of the study cohorts. Using negative binomial regression models, we tested whether the incidence rate of psychiatric comorbidity was elevated in the individual and combined IMID cohorts versus the matched cohorts, adjusting for sex, age, region of residence, socioeconomic status and year.nnnRESULTSnThe relative incidence of depression (incidence rate ratio [IRR] 1.71; 95%CI: 1.64-1.79), anxiety (IRR 1.34; 95%CI: 1.29-1.40), bipolar disorder (IRR 1.68; 95%CI: 1.52-1.85) and schizophrenia (IRR 1.32; 95%CI: 1.03-1.69) were elevated in the IMID cohort. Depression and anxiety affected the MS population more often than the IBD and RA populations.nnnCONCLUSIONSnIndividuals with IMID, including IBD, MS and RA are at increased risk of psychiatric comorbidity. This increased risk appears non-specific as it is seen for all three IMIDs and for all psychiatric disorders studied, implying a common underlying biology for psychiatric comorbidity in those with IMID.


Jcr-journal of Clinical Rheumatology | 2017

Systematic Review and Meta-analysis of Interventions for Depression and Anxiety in Persons With Rheumatoid Arthritis

Kirsten M. Fiest; Carol A. Hitchon; Charles N. Bernstein; Christine A. Peschken; John R. Walker; Lesley A. Graff; Ahmed M Abou-Setta; Scott B. Patten; Jitender Sareen; James M. Bolton; Ruth Ann Marrie

Background Psychiatric comorbidities, such as depression and anxiety, are very common in persons with rheumatoid arthritis (RA) and can lead to adverse outcomes. By appropriately treating these comorbidities, disease-specific outcomes and quality of life may be improved. Objective The aim of this study was to systematically review the literature from controlled trials of treatments for depression and anxiety in persons with RA. Methods We searched multiple online databases from inception until March 25, 2015, without restrictions on language, date, or location of publication. We included controlled trials conducted in persons with RA and depression or anxiety. Two independent reviewers extracted information including trial and participant characteristics. The standardized mean differences (SMDs) of depression or anxiety scores at postassessment were pooled between treatment and comparison groups, stratified by active versus inactive comparators. Results From 1291 unique abstracts, we included 8 RA trials of depression interventions (6 pharmacological, 1 psychological, 1 both). Pharmacological interventions for depression with inactive comparators (n = 3 trials, 143 participants) did not reduce depressive symptoms (SMD, −0.21; 95% confidence interval [CI], −1.27 to 0.85), although interventions with active comparators (n = 3 trials, 190 participants) did improve depressive symptoms (SMD, −0.79; 95% CI, −1.34 to −0.25). The single psychological trial of depression treatment in RA did not improve depressive symptoms (SMD, −0.44; 95% CI, −0.96 to 0.08). Seven of the trials had an unclear risk of bias. Conclusions Few trials examining interventions for depression or anxiety in adults with RA exist, and the level of evidence is low to moderate because of the risk of bias and small number of trials.


Epidemiology and Psychiatric Sciences | 2017

Rising incidence of psychiatric disorders before diagnosis of immune-mediated inflammatory disease

Ruth Ann Marrie; Randy Walld; James M. Bolton; Jitender Sareen; John R. Walker; Scott B. Patten; Alexander Singer; Lisa M. Lix; Carol A. Hitchon; Renée El-Gabalawy; Alan Katz; John D. Fisk; Charles N. Bernstein

Aims. After the diagnosis of immune-mediated inflammatory diseases (IMID) such as inflammatory bowel disease (IBD), multiple sclerosis (MS) and rheumatoid arthritis (RA), the incidence of psychiatric comorbidity is increased relative to the general population. We aimed to determine whether the incidence of psychiatric disorders is increased in the 5 years before the diagnosis of IMID as compared with the general population. Methods. Using population-based administrative health data from the Canadian province of Manitoba, we identified all persons with incident IBD, MS and RA between 1989 and 2012, and cohorts from the general population matched 5 : 1 on year of birth, sex and region to each disease cohort. We identified members of these groups with at least 5 years of residency before and after the IMID diagnosis date. We applied validated algorithms for depression, anxiety disorders, bipolar disorder, schizophrenia, and any psychiatric disorder to determine the annual incidence of these conditions in the 5-year periods before and after the diagnosis year. Results. We identified 12 141 incident cases of IMID (3766 IBD, 2190 MS, 6350 RA) and 65 424 matched individuals. As early as 5 years before diagnosis, the incidence of depression [incidence rate ratio (IRR) 1.54; 95% CI 1.30–1.84) and anxiety disorders (IRR 1.30; 95% CI 1.12–1.51) were elevated in the IMID cohort as compared with the matched cohort. Similar results were obtained for each of the IBD, MS and RA cohorts. The incidence of bipolar disorder was elevated beginning 3 years before IMID diagnosis (IRR 1.63; 95% CI 1.10–2.40). Conclusion. The incidence of psychiatric comorbidity is elevated in the IMID population as compared with a matched population as early as 5 years before diagnosis. Future studies should elucidate whether this reflects shared risk factors for psychiatric disorders and IMID, a shared final common inflammatory pathway or other aetiology.


Journal of Psychosomatic Research | 2017

Measurement invariance across Genders on the Childhood Illness Attitude Scales (CIAS)

Audur S. Thorisdottir; Anna Villadsen; Daniel M. LeBouthillier; Charlotte Ulrikka Rask; Kristi D. Wright; John R. Walker; Steven Feldgaier; Gordon J.G. Asmundson

OBJECTIVEnThe Childhood Illness Attitude Scales (CIAS) were created as a developmentally appropriate measure for symptoms of health anxiety (HA) in school-aged children. Despite overall sound psychometric properties reported in previous studies, more comprehensive examination of the latent structure and potential response bias in the CIAS is needed. The purpose of the present study was to cross-validate the latent structure of the CIAS across genders and to examine gender-specific variations in CIAS scores.nnnMETHODSnThe sample comprised data from 602 Canadian and Danish school-aged children (Mage=10.54, SD=0.99; 52.5% girls). Confirmatory factor analyses were conducted to test 3-, modified 3-, and 4-factor models in both samples. Multigroup confirmatory factor analysis was performed to test factor structure invariance across boys and girls in a combined sample. Differential Item Functioning (DIF) was assessed using test characteristic curves.nnnRESULTSnA modified 3-factor solution (i.e., fears=11 items, help-seeking=6 items, and symptom effects=4 items) provided the best fit to the data (χ2 (364, N=602)=681.7, p<0.001; χ2/df=1.803; RMSEA=0.037; CFI=0.926). The factor structure was stable, well-fitting, and indicated measurement invariance across groups. DIF analyses revealed no gender-based response bias at the scale level.nnnCONCLUSIONnResults support a revised 3-factor version of the CIAS that can be used with confidence to assess symptoms of HA in school-aged boys and girls.


Inflammatory Bowel Diseases | 2017

Coping with Inflammatory Bowel Disease: Engaging with Information to Inform Health-Related Decision Making in Daily Life

Gayle Restall; Alexandria M. Simms; John R. Walker; Clove Haviva; Lesley A. Graff; Kathryn A. Sexton; Norine Miller; Laura E. Targownik; Charles N. Bernstein

Background: People with inflammatory bowel disease (IBD) require disease and lifestyle information to make health-related decisions in their daily lives. Derived from a larger qualitative study of the lived experiences of people with IBD, we report on findings that explored how people with IBD engage with health-related information in their daily lives. Methods: Participants were recruited primarily from the Manitoba IBD Cohort Study. We used purposive sampling to select people with a breadth of characteristics and experiences. Individual interviews were audio-recorded and transcribed verbatim. Data were analyzed using inductive qualitative methods consistent with a phenomenological approach. Results: Forty-five people with IBD participated; 51% were women. Findings highlighted the temporal and contextual influences on engagement with health-related information. Temporal influences were described as the changing need for health-related information over time. Participants identified 6 contextual factors influencing engagement with information to make health decisions: (1) emotional and attitudinal responses, (2) perceived benefits and risks, (3) trust in the source of the information, (4) knowledge and skills to access and use information, (5) availability of evidence to support decisions, and (6) social and economic environments. Conclusions: Findings illustrate the changing needs for health-related information over the course of IBD, and with evolving health and life circumstances. Practitioners can be responsive to information needs of people with IBD by having high-quality information available at the right time in a variety of formats and by supporting the incorporation of information in daily life.


Gastroenterology | 2017

Independent Validation of a Self-Report Version of the IBD Disability Index (IBDDI) in a Population-Based Cohort of IBD Patients

Leigh Anne Shafer; John R. Walker; Tarun Chhibba; Melony Ivekovic; Harminder Singh; Laura E. Targownik; Laurent Peyrin-Biroulet; Corinne Gower-Rousseau; Hélène Sarter; Charles N. Bernstein

Introduction A new clinician-administered inflammatory bowel disease (IBD) Disability Index (IBDDI) was recently developed and validated among a population in France. We aimed to validate the IBDDI in a North American setting and adapt for use as a self-report tool. Methods Persons 18-65 years old from the population-based University of Manitoba IBD Research Registry were mailed a self-administered survey. This survey included the IBDDI and several scales that should correlate with a disability measure- the World Health Organization (WHO) Disability Assessment Scale (WHODAS) 2.0, Work and Social Adjustment Scale (WSAS), the Inflammatory Bowel Disease Questionnaire (IBDQ), and the K6-Kessler Emotional Distress Scale. We used Pearson correlation coefficients to assess construct validity, Cronbachs alpha to assess internal consistency, and Factor analysis to assess which of the IBDDI items likely belonged to a single IBD-related disability factor. Results In response to the survey request,1143 (46% of those contacted) participated (61% female, mean age 51, 52% with Crohns disease). On an index scale from 0-100, 14% had a score ≥50 (extreme disability, 18% of those with Crohns disease; 10% of those with ulcerative colitis). There were strong correlations between IBDDI and WSAS (0.76), WHODAS (0.76), K6 (0.73), and an inverse correlation with IBDQ (-0.86). The Cronbachs alpha was high (0.88). All but 2 items (number of liquid stools in the past week and arthritis/arthralgia) of the 14 identified for IBDDI loaded highly onto a single factor (factor loading > 0.40). Conclusions The findings support the validity of this new self-report version of the IBDDI as a sound measure of disability in IBD.


Digestive Diseases and Sciences | 2017

Symptoms of Functional Intestinal Disorders Are Common in Patients with Celiac Disease Following Transition to a Gluten-Free Diet

Jocelyn A. Silvester; Lesley A. Graff; Lisa Rigaux; Charles N. Bernstein; Daniel A. Leffler; Ciaran P. Kelly; John R. Walker; Donald R. Duerksen

BackgroundCeliac disease and functional intestinal disorders may overlap, yet the natural history of functional symptoms in patients with celiac disease is unknown.AimTo investigate the prevalence of irritable bowel syndrome (IBS), functional dyspepsia (FD), and functional bloating (FB) symptoms among patients with celiac disease at diagnosis and during the first year of a gluten-free diet.MethodsAdults with a new diagnosis of celiac disease were surveyed at baseline, 6xa0months and 1xa0year using standardized measures for intestinal symptoms [Rome III diagnostic questionnaire and celiac symptom index (CSI)] and gluten-free diet adherence [gluten-free eating assessment tool (GF-EAT) and celiac diet adherence test].ResultsAt diagnosis, two-thirds fulfilled Rome III diagnostic questionnaire symptom criteria for IBS (52%), functional dyspepsia (27%), and/or functional bloating (9%). One year post-diagnosis, there was high adherence to a gluten-free diet as 93% reported gluten exposure less than once per month on the GF-EAT and only 8% had ongoing celiac disease symptoms (CSI score >45). The rates of those meeting IBS (22%) and functional dyspepsia (8%) symptom criteria both decreased significantly on a gluten-free diet. The prevalence of functional symptoms (any of IBS, FD or FB) at 1xa0year was 47%.ConclusionsLong-term follow-up of patients with celiac disease is necessary because many patients with celiac disease who are adherent to a gluten-free diet have persistent gastrointestinal symptoms.


Clinical Gastroenterology and Hepatology | 2017

Workplace Accommodation for Persons With IBD: What Is Needed and What Is Accessed

Tarun Chhibba; John R. Walker; Kathryn A. Sexton; Gayle Restall; Melony Ivekovic; Leigh Ann Shafer; Harminder Singh; Laura E. Targownik; Charles N. Bernstein

BACKGROUND & AIMS: People with inflammatory bowel disease (IBD) often experience periods of illness that interfere with their ability to work. We aimed to understand the need for workplace accommodation during periods of acute illness among persons IBD. METHODS: Participants were recruited from the population‐based University of Manitoba Research Registry and received a survey including questions assessing experiences with workplace accommodations. Data were analyzed using descriptive statistics and multivariate logistic regression modelling. RESULTS: A total of 1143 individuals responded to the survey (46% response rate), of whom 881 had experienced IBD symptoms in the workplace and were included in the analysis. The mean age was 48.3 years (standard deviation, 10.9); 61% were female. Mean IBD duration was 20.6 years (standard deviation, 10.5). Most respondents (73%) described IBD symptoms experienced in the workplace as severe to very severe. The most commonly required accommodations were time to go to medical appointments during working hours (81%), easy access to a toilet (71%), and a chance to take a break when not feeling well (54%). Most accommodations were arranged informally or through a supervisor. The accommodations required were very or somewhat easy to arrange about half the time. Being female, having high symptom severity, and high level of current distress were associated with a need for more accommodations, difficulty implementing accommodations, and not asking for needed accommodations. CONCLUSIONS: This study provides important information as to the types of accommodations that are necessary, common practices arranging for these, and level of difficulty arranging accommodations. Furthermore, characteristics associated with greater need for accommodation, reluctance to ask for them, and difficulty in arranging them were identified.


Inflammatory Bowel Diseases | 2017

Health Care Services in IBD: Factors Associated with Service Utilization and Preferences for Service Options for Routine and Urgent Care

Matthew T. Bernstein; John R. Walker; Tarun Chhibba; Melony Ivekovic; Harminder Singh; Laura E. Targownik; Charles N. Bernstein


Archive | 2017

Phenomenology of Health Anxiety

John R. Walker; Patricia Furer

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