Olafur S. Palsson

Northwestern University, Evanston, Illinois, United States

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Publications (162)1821.44 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Background/aims: Reliable diagnostic instruments for measuring the presence of functional gastrointestinal disorders based on the Rome III criteria have been lacking in Japan. The aims of the present study were to translate and validate the Rome III diagnostic questionnaire which was widely used in Western countries. Methods: The original version of Rome III diagnostic questionnaire was translated from English into Japanese through 3 independent forward translations, resolution, back translation and reconciliation of the differences. Forty-nine patients with irritable bowel syndrome (IBS), 32 patients with functional dyspepsia (FD) and 56 subjects without any current GI symptoms as controls were recruited from three hospitals located in different regions of Japan and completed the IBS and FD diagnostic modules twice within 14 days. Kappa statistic was used to assess test-retest reliability. The sensitivity and specificity of each diagnostic module for distinguishing IBS or FD patients from controls was tested. Results: Median kappa statistics were 0.63 for the translated IBS diagnostic module and 0.68 for the FD module. The sensitivity, specificity, and positive predict value of the IBS module against physician diagnosis was 61.2%, 100%, and 100% and those of the FD module was 53.2%, 98.2%, and 94.4%, respectively. Meanwhile, IBS patients were significantly more likely to report blood in stools compared to controls (18.4% vs 1.8%, P < 0.01). Conclusions: The IBS and FD diagnostic modules on the Japanese version of the Rome III diagnostic questionnaire are valid and reliable. Further studies are warranted to elucidate the diagnostic utility of the red flag questionnaire.
    Journal of neurogastroenterology and motility 09/2015; DOI:10.5056/jnm15016 · 2.30 Impact Factor
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    Olafur S Palsson · Miranda Van Tilburg
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    ABSTRACT: Completely scripted treatment courses for verbatim interventions are uncommon in the field of clinical hypnosis. This approach was adopted for by a North Carolina research team for treating gastrointestinal disorders 20 years ago and has been used in hypnosis treatment of irritable bowel syndrome and ulcerative colitis, as well as in guided imagery treatment for functional abdominal pain. Treatment with these scripted protocols is delivered in a fixed series of sessions over a 2- or 3-month period. They have been found efficacious for improving bowel symptoms in several clinical trials, even in patients who have been entirely unresponsive to medical treatment. Response rates in clinical trials have ranged from 53% to 94%, and the therapeutic benefits have been shown to be well maintained at 6-, 10-, or 12-month follow-ups in different studies. This article describes the development and research on these protocols and summarizes the advantages and limitations of this fully scripted treatment approach.
    The American journal of clinical hypnosis 07/2015; 58(1). DOI:10.1080/00029157.2015.1012705 · 0.53 Impact Factor
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    ABSTRACT: Theory suggests that heightening state mindfulness in meditation practice over time increases trait mindfulness, which benefits psychological health. We prospectively examined individual trajectories of state mindfulness in meditation during a mindfulness-based intervention in relation to changes in trait mindfulness and psychological distress. Each week during the eight-week intervention, participants reported their state mindfulness in meditation after a brief mindfulness meditation. Participants also completed pre- and post-intervention measures of trait mindfulness and psychological symptoms. Tests of combined latent growth and path models suggested that individuals varied significantly in their rates of change in state mindfulness in meditation during the intervention, and that these individual trajectories predicted pre-post intervention changes in trait mindfulness and distress. These findings support that increasing state mindfulness over repeated meditation sessions may contribute to a more mindful and less distressed disposition. However, individuals' trajectories of change may vary and warrant further investigation.
    Personality and Individual Differences 07/2015; DOI:10.1016/j.paid.2014.12.044 · 1.86 Impact Factor
  • Olafur S. Palsson · Steve Heymen · William E. Whitehead
    Gastroenterology 04/2015; 148(4):S-780. DOI:10.1016/S0016-5085(15)32661-5 · 16.72 Impact Factor
  • Steve Heymen · Olafur S. Palsson · William E. Whitehead
    Gastroenterology 04/2015; 148(4):S-298. DOI:10.1016/S0016-5085(15)30986-0 · 16.72 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-302-S-303. DOI:10.1016/S0016-5085(15)30998-7 · 16.72 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-779. DOI:10.1016/S0016-5085(15)32658-5 · 16.72 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-194. DOI:10.1016/S0016-5085(15)30646-6 · 16.72 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-298. DOI:10.1016/S0016-5085(15)30985-9 · 16.72 Impact Factor
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    ABSTRACT: Omega-3 and omega-6 fatty acids are precursors of bioactive lipid mediators posited to modulate both physical pain and psychological distress. In a randomized trial of 67 subjects with severe headaches, we recently demonstrated that targeted dietary manipulation-increasing omega-3 fatty acids with concurrent reduction in omega-6 linoleic acid (the H3-L6 intervention)-produced major reductions in headache compared with an omega-6 lowering (L6) intervention. Because chronic pain is often accompanied by psychological distress and impaired health-related quality of life (HRQOL), we used data from this trial to examine whether the H3-L6 intervention favorably impacted these domains. Additionally, we examined the effect of the interventions on the number of cases with substantial physical or mental impairments as defined by cutoff values in the Brief Symptom Inventory (BSI-18), Medical Outcomes Study Short Forms 12 (SF-12), Headache Impact Test (HIT-6), and the number of headache days per month. In the intention-to-treat analysis, participants in the H3-L6 group experienced statistically significant reductions in psychological distress (BSI-18 mean difference: -6.56; 95% confidence interval [CI]: -11.43 to -1.69) and improvements in SF-12 mental (mean difference: 6.01; 95% CI: 0.57 to 11.45) and physical (mean difference: 6.65; 95% CI: 2.14 to 11.16) health summary scores. At 12 weeks, the proportion of subjects experiencing substantial impairment according to cutoff values in the BSI-18, SF-12 physical, HIT-6, and headache days per month was significantly lower in the H3-L6 group. Dietary manipulation of n-3 and n-6 fatty acids, previously shown to produce major improvements in headache, was found to also reduce psychological distress and improve HRQOL and function.
    Pain 04/2015; 156(4). DOI:10.1097/01.j.pain.0000460348.84965.47 · 5.21 Impact Factor
  • Olafur S. Palsson · Steve Heymen · William E. Whitehead
    Gastroenterology 04/2015; 148(4):S-305. DOI:10.1016/S0016-5085(15)31006-4 · 16.72 Impact Factor
  • Gastroenterology 04/2015; 148(4):S-38. DOI:10.1016/S0016-5085(15)30132-3 · 16.72 Impact Factor
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    Megan E. Riehl · John E. Pandolfino · Olafur S. Palsson · Laurie Keefer
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    ABSTRACT: Functional heartburn (FH) is a benign but burdensome condition characterized by painful, burning epigastric sensations in the absence of acid reflux or symptom-reflux correlation. Esophageal hypersensitivity and its psychological counterpart, esophageal hypervigilance (EHv) drive symptom experience. Hypnotherapy (HYP) is an established and preferred intervention for refractory symptoms in functional gastrointestinal disorders (FGIDs) and could be applied to FH. The objective of this study was to determine the feasibility, acceptability, and clinical utility of 7 weekly sessions of esophageal-directed HYP (EHYP) on heartburn symptoms, quality of life, and EHv. Similar to other work in FGIDs and regardless of hypnotizability, there were consistent and significant changes in heartburn symptoms, visceral anxiety, and quality of life and a trend for improvement in catastrophizing. We would recommend EHYP in FH patients who are either non-responsive to medications or who would prefer a lifestyle intervention.
    Diseases of the Esophagus 03/2015; 148(4). DOI:10.1111/dote.12353 · 1.78 Impact Factor
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    ABSTRACT: To determine the prevalence of gastrointestinal symptoms suggestive of an infant/toddler functional gastrointestinal disorder (FGID) as reported by parents in a representative community sample. Mothers (n = 320) of children aged 0-3 years old were recruited in the US and completed a questionnaire about their child's and their own gastrointestinal symptoms. By Rome criteria, 27% of infants/toddlers qualified for FGIDs. Infant regurgitation was the most common disorder in infants and functional constipation in toddlers. No age, sex, or race differences were found in FGID diagnoses. Compared with those who did not meet Rome criteria, toddlers with FGID had lower quality of life (M = 80.1 vs M = 90.3, P < .001), increased medical visits (M = 0.38 vs 0.14; P < .05), mental health visits (M = 0.29 vs 0.06; P < .05), and hospital stays (M = 0.35 vs 0.06; P < .01). A child was more likely to suffer from hard stools if the parent also reported hard stools (P = .02), but similar association was not found with loose stools. FGIDs are common in infants and toddlers and can be identified in the general population. They do not vary with sex and race. Quality of life is reduced in those with FGIDs. More research is needed into these largely neglected conditions as it may improve the lives of a significant number of young children. Copyright © 2015 Elsevier Inc. All rights reserved.
    Journal of Pediatrics 12/2014; 166(3). DOI:10.1016/j.jpeds.2014.11.039 · 3.79 Impact Factor
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    ABSTRACT: Although essential, many medical practices are unable to adequately support irritable bowel syndrome (IBS) patient self-management. Web-based programs can help overcome these barriers. We developed, assessed, and refined an integrated IBS self-management program (IBS Self-care). We then conducted a 12-week pilot test to assess program utilization, evaluate its association with patients' self-efficacy and quality of life, and collect qualitative feedback to improve the program. 40 subjects with generally mild IBS were recruited via the Internet to participate in a 12-week pilot study. Subjects found the website easy to use (93%) and personally relevant (95%), and 90% would recommend it to a friend. Self-rated IBS knowledge increased from an average of 47.1 on a 100-point VAS scale (SD 22.1) at baseline to 77.4 (SD: 12.4) at week 12 (p < 0.0001). There were no significant changes in patient self-efficacy (Patient Activation Measure) or quality of life (IBS -Quality of Life Scale). The IBS Self-Care program was well received by users who after 12 weeks reported improved knowledge about IBS, but no significant changes in self-efficacy or quality of life. If applied to the right population, this low cost solution can overcome some of the deficiencies of medical care and empower individuals to better manage their own IBS. © 2014 John Wiley & Sons Ltd.
    Neurogastroenterology and Motility 12/2014; 27(1). DOI:10.1111/nmo.12487 · 3.59 Impact Factor
  • Olafur S Palsson · Jeffrey Baggish · William E Whitehead
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    ABSTRACT: Objectives: The objectives of this study were to determine whether the symptoms of diarrhea (defined as loose or watery stools), constipation (hard or lumpy stools), abdominal pain, and bloating occur in episodes rather than sporadically in patients with irritable bowel syndrome (IBS); to identify rules for defining the onset and termination of symptom episodes; and to assess the overlap of these episodes. Methods: IBS patients kept a symptom log in which they rated the consistency of each bowel movement (BM) on the Bristol Stool Scale for 3 months. Each night they transferred these data to an internet website and also rated abdominal pain and bloating for that day. Data were analyzed for 124 patients who completed at least 21 consecutive diary days (mean of 73 days) without taking laxative, antidiarrheal, or IBS-specific medications. For each symptom in each patient, we computed the correlation between consecutive observations (autocorrelations) in the diary to determine whether the symptom tended to occur in clusters of several instances, as would happen in episodes vs. happening randomly. Next, we compared different patterns by which diarrhea and nondiarrhea stools alternate to identify episode definitions that captured at least 75% of loose/watery stools. A similar pattern analysis was performed for constipation. Pain and bloating episodes were defined as days with an intensity rating >3 on a 0-10 scale. These patterns were converted into rules for defining the onset and termination of symptom episodes. Last, we used these episode definitions to examine the overlap of pain with episodes of diarrhea, constipation, and pain. Results: Significant (P<0.05) autocorrelations were found in the Bristol Stool Scale ratings of 69.4% of patients and in the daily abdominal pain and bloating ratings of 52.4% and 68.5% of patients, respectively. Defining a diarrhea episode as two or more loose/watery stools never separated by >1 nonloose/watery stool or by a day without a BM captured 76% of all loose/water stools. Defining constipation episodes as two or more hard/lumpy stools never separated by >1 nonhard/lumpy stool captured 80% of hard/lumpy stools. Sequences of 3 or more days without a BM were also defined as constipation episodes because they were strongly associated with hard stools. Average episode durations were 2.1 days for diarrhea, 4.5 days for constipation, 3.1 days for pain, and 3.5 days for bloating. Overlap analysis showed that only 41.6% of constipation episode days and 67.0% of diarrhea episode days were pain episode days. Bloating and pain coexisted on 59.1% of days on which either type occurred. Conclusions: Loose/watery stools and hard/lumpy stools occur in well-defined episodes. Pain and bloating also occur in episodes, but contrary to the Rome criteria more than half of the pain episodes occur outside episodes of abnormal stool consistency.
    The American Journal of Gastroenterology 07/2014; 109(9). DOI:10.1038/ajg.2014.181 · 10.76 Impact Factor
  • Gastroenterology 05/2014; 146(5):S-143. DOI:10.1016/S0016-5085(14)60506-0 · 16.72 Impact Factor
  • Gastroenterology 05/2014; 146(5):S-109. DOI:10.1016/S0016-5085(14)60392-9 · 16.72 Impact Factor
  • Gastroenterology 05/2014; 146(5):S-721. DOI:10.1016/S0016-5085(14)62614-7 · 16.72 Impact Factor
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    ABSTRACT: Background In a recent double-blinded clinical trial, the probiotic combination of Lactobacillus acidophilus NCFM (L-NCFM) and B-LBi07 reduced bloating symptoms in patients with functional bowel disorders; an effect more evident in those who reported abdominal pain. In mice, L-NCFM but not B-LBi07 induced colonic mu-opioid receptor (MOR) and cannabinoid receptor 2 (CB2) expression, and reduced visceral sensitivity.AimsTo determine if L-NCFM was the active component in the clinical trial and to investigate the mechanism of action in humans with mild to moderate abdominal pain.Methods Caucasian women (n = 20) 18–70 years with mild to moderate abdominal pain were enrolled in a double-blind, two-armed, single-centre study. Patients were given either L-NCFM alone or in combination with B-LBi07 for 21 days at a total dose of 2×1010 CFU b.d. Colonic biopsies were collected during unsedated, unprepped flexible sigmoidoscopy before and at the end of probiotic consumption. mRNA and immunostaining were then performed on these biopsies. Patients kept symptom diaries for the 7 days prior to starting probiotic therapy and for the last 7 days of therapy.ResultsL-NCFM alone, but not with B-LBi07, induced colonic MOR mRNA and protein expression, as well as downstream signalling, as measured by enterocyte STAT3-phosphorylation. In contrast, CB2 expression was decreased. Both treatment groups trended towards improvement in symptoms, but the study was insufficiently powered to draw meaningful conclusions.Conclusions Lactobacillus acidophilus NCFM modulates mu-opioid receptor expression and activity, while the combination of L-NCFM and B-LBi07 does not. This study provides a possible mechanism for action by which probiotics modulates pain sensation in humans (Clinical Trial Number: NCT01064661).
    Alimentary Pharmacology & Therapeutics 05/2014; 40(2). DOI:10.1111/apt.12800 · 5.73 Impact Factor

Publication Stats

2k Citations
1,821.44 Total Impact Points


  • 2015
    • Northwestern University
      • Division of Gastroenterology and Hepatology
      Evanston, Illinois, United States
  • 2001–2015
    • University of North Carolina at Chapel Hill
      • • Center for Gastrointestinal Biology and Disease
      • • Department of Obstetrics and Gynecology
      • • Department of Medicine
      • • Center for Functional GI and Motility Disorders
      • • School of Social Work
      • • Division of Gastroenterology and Hepatology
      North Carolina, United States
  • 2007
    • University of North Carolina at Charlotte
      Charlotte, North Carolina, United States
  • 1998–2003
    • Eastern Virginia Medical School
      Norfolk, Virginia, United States