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Featured researches published by Perjohan Lindfors.


The American Journal of Gastroenterology | 2011

Internet-Delivered Exposure-Based Treatment vs. Stress Management for Irritable Bowel Syndrome: A Randomized Trial

Brjánn Ljótsson; Erik Hedman; Erik Andersson; Hugo Hesser; Perjohan Lindfors; Timo Hursti; Sara Rydh; Christian Rück; Nils Lindefors; Gerhard Andersson

OBJECTIVES:Our research group has developed an internet-delivered cognitive behavioral treatment (ICBT) for irritable bowel syndrome (IBS). We compared ICBT with internet-delivered stress management (ISM) for IBS to assess whether the effects of ICBT are specific.METHODS:This was a randomized controlled trial, including 195 self-referred participants diagnosed with IBS. The treatment interventions lasted for 10 weeks and included an online therapist contact. The ICBT emphasized acceptance of symptoms through exposure to IBS symptoms and related negative feelings. The ICBT also included mindfulness training. The ISM emphasized symptom control through relaxation techniques, dietary adjustments, and problem-solving skills. Severity of IBS symptoms was measured with the gastrointestinal symptom rating scale—IBS version (GSRS-IBS). Credibility of the treatments and expectancy of improvement were assessed with the treatment credibility scale. The participants’ perceived therapeutic alliance with their online therapist was measured with the working alliance inventory.RESULTS:At post-treatment and 6-month follow-up, 192 (99%) and 169 (87%) participants returned data, respectively. At post-treatment and 6-month follow-up, we found significant differences on the GSRS-IBS, favoring ICBT. The difference on GSRS-IBS scores was 4.8 (95% confidence interval (CI): 1.2–8.4) at post-treatment and 5.9 (95% CI: 1.9–9.9) at 6-month follow-up. There were no significant differences on the treatment credibility scale or the working alliance inventory between the groups.CONCLUSIONS:Internet-delivered CBT has specific effects that cannot be attributed only to treatment credibility, expectancy of improvement, therapeutic alliance, or attention. Furthermore, a treatment based on exposure exercises specifically tailored for IBS may be a better treatment option than general stress and symptom management for IBS patients. ICBT is a promising treatment modality for IBS as it can be offered to IBS patients in much larger scale than conventional psychological treatments.


Behaviour Research and Therapy | 2011

Long-term follow-up of internet-delivered exposure and mindfulness based treatment for irritable bowel syndrome.

Brjánn Ljótsson; Erik Hedman; Perjohan Lindfors; Timo Hursti; Nils Lindefors; Gerhard Andersson; Christian Rück

We conducted a follow-up of a previously reported study of internet-delivered cognitive behavior therapy (CBT) for IBS, based on exposure and mindfulness exercises (Ljótsson et al. (2010). Internet-delivered exposure and mindfulness based therapy for irritable bowel syndrome - a randomized controlled trial. Behaviour Research and Therapy, 48, 531-539). Seventy-five participants from the original sample of 85 (88%) reported follow-up data at 15-18 months (mean 16.4 months) after completing treatment. The follow-up sample included participants from both the original studys treatment group and waiting list after it had been crossed over to treatment. Intention-to-treat analysis showed that treatment gains were maintained on all outcome measures, including IBS symptoms, quality of life, and anxiety related to gastrointestinal symptoms, with mainly large effect sizes (within-group Cohens d=0.78-1.11). A total of fifty participants (59% of the total original sample; 52% of the original treatment group participants and 65% of the original waiting list participants) reported adequate relief of symptoms. Improvements at follow-up were more pronounced for the participants that had completed the full treatment and maintenance of improvement did not seem to be dependent on further treatment seeking. This study suggests that internet-delivered CBT based on exposure and mindfulness has long-term beneficial effects for IBS-patients.


BMC Gastroenterology | 2011

Acceptability, effectiveness, and cost-effectiveness of internet-based exposure treatment for irritable bowel syndrome in a clinical sample: a randomized controlled trial

Brjánn Ljótsson; Gerhard Andersson; Erik Andersson; Erik Hedman; Perjohan Lindfors; Sergej Andréewitch; Christian Rück; Nils Lindefors

BackgroundInternet-based cognitive behavior therapy (ICBT) has shown promising effects in the treatment of irritable bowel syndrome (IBS). However, to date no study has used a design where participants have been sampled solely from a clinical population. We aimed to investigate the acceptability, effectiveness, and cost-effectiveness of ICBT for IBS using a consecutively recruited sample from a gastroenterological clinic.MethodsSixty-one patients were randomized to 10 weeks of ICBT (n = 30) or a waiting list control (n = 31). The ICBT was guided by an online therapist and emphasized acceptance of symptoms through exposure and mindfulness training. Severity of IBS symptoms was measured with the Gastrointestinal symptom rating scale - IBS version (GSRS-IBS). Patients in both groups were assessed at pre- and post-treatment while only the ICBT group was assessed 12 months after treatment completion. Health economic data were also gathered at all assessment points and analyzed using bootstrap sampling.ResultsFifty of 61 patients (82%) completed the post-treatment assessment and 20 of 30 patients (67%) in the ICBT group were assessed at 12-month follow-up. The ICBT group demonstrated significantly (p < .001) larger improvements on the IBS-related outcome scales than the waiting list group. The between group effect size on GSRS-IBS was Cohens d = 0.77 (95% CI: 0.19-1.34). Similar effects were noted on measures of quality of life and IBS-related fear and avoidance behaviors. Improvements in the ICBT group were maintained at 12-month follow-up. The ICBT condition was found to be more cost-effective than the waiting list, with an 87% chance of leading to reduced societal costs combined with clinical effectiveness. The cost-effectiveness was sustained over the 12-month period.ConclusionsICBT proved to be a cost-effective treatment when delivered to a sample recruited from a gastroenterological clinic. However, many of the included patients dropped out of the study and the overall treatment effects were smaller than previous studies with referred and self-referred samples. ICBT may therefore be acceptable and effective for only a subset of clinical patients. Study dropout seemed to be associated with severe symptoms and large impairment. Objective and empirically validated criteria to select which patients to offer ICBT should be developed.Trial RegistrationClinicalTrials.gov: NCT00844961


Journal of Consulting and Clinical Psychology | 2013

Mechanisms of change in an exposure-based treatment for irritable bowel syndrome.

Brjánn Ljótsson; Hugo Hesser; Erik Andersson; Perjohan Lindfors; Timo Hursti; Christian Rück; Nils Lindefors; Gerhard Andersson; Erik Hedman

OBJECTIVE The aim of this study was to identify mediators of change in a previously published randomized controlled trial that compared Internet-delivered cognitive behavioral treatment based on exposure exercises (ICBT) with Internet-delivered stress management (ISM) for irritable bowel syndrome (IBS). ICBT and ISM targeted distinct proposed mechanisms of illness maintenance and symptom exacerbation, gastrointestinal symptom-specific anxiety (GSA), and stress reactivity, respectively. The original study found that ICBT was more effective than ISM in improving IBS symptoms. METHOD Weekly measurements of GSA and stress reactivity (putative mediators) and treatment outcome were obtained from 195 participants with IBS, who had been randomized to ICBT or ISM. RESULTS Parallel process growth mediational analyses revealed that the larger reduction of IBS symptoms from ICBT compared to ISM was mediated by changes in GSA, αβ = -0.42, 95% CI asymmetric [-0.71, -0.16]. In contrast, changes in stress reactivity did not mediate the difference in outcomes between treatments, αβ = 0.04, 95% CI asymmetric [-0.09, 0.20]. Analyses of the temporal sequence of week-to-week changes in process and outcome measures showed that only GSA displayed a pattern consistent with a causal model in which change in process preceded and contributed to symptom change. Furthermore, engagement in treatment specific activities was related to change in GSA but not to stress reactivity in the ICBT arm, whereas treatment specific activities were not related to change in any of the putative processes in the ISM arm. CONCLUSIONS We conclude that ICBT works through directly targeting GSA, rather than by means of reducing stress reactivity.


Behaviour Research and Therapy | 2014

Provoking symptoms to relieve symptoms: A randomized controlled dismantling study of exposure therapy in irritable bowel syndrome

Brjánn Ljótsson; Hugo Hesser; Erik Andersson; Jeffrey M. Lackner; Samir El Alaoui; Lisa Falk; Kristina Aspvall; Josefin Fransson; Klara Hammarlund; Anna Löfström; Sanna Nowinski; Perjohan Lindfors; Erik Hedman

An internet-delivered cognitive behavioral treatment (ICBT) based on systematic exposure exercises has previously shown beneficial effects for patients with irritable bowel syndrome (IBS). Exposure exercises may be perceived as difficult for patients to perform because of the elicited short-term distress and clinicians may be reluctant to use these interventions. The aim of this study was to compare ICBT with the same protocol without systematic exposure (ICBT-WE) to assess if exposure had any incremental value. This randomized controlled dismantling study included 309 participants diagnosed with IBS. The treatment interventions lasted for 10 weeks and included online therapist contact. ICBT-WE comprised mindfulness, work with life values, acceptance, and encouraged reduced avoidance behaviors, while ICBT also included systematic exposure to IBS symptoms and related situations. Severity of IBS symptoms was measured with the Gastrointestinal Symptom Rating Scale - IBS version (GSRS-IBS). The between-group Cohens d on GSRS-IBS was 0.47 (95% CI: 0.23-0.70) at post-treatment and 0.48 (95% CI: 0.20-0.76) at 6-month follow-up, favoring ICBT. We conclude that the systematic exposure included in the ICBT protocol has incremental effects over the other components in the protocol. This study provides evidence for the utility of exposure exercises in psychological treatments for IBS.


Gut | 2018

Multivariate modelling of faecal bacterial profiles of patients with IBS predicts responsiveness to a diet low in FODMAPs

Sean M. Bennet; Lena Böhn; Stine Störsrud; Therese M. Liljebo; Lena Collin; Perjohan Lindfors; Hans Törnblom; Lena Öhman; Magnus Simren

Objective The effects of dietary interventions on gut bacteria are ambiguous. Following a previous intervention study, we aimed to determine how differing diets impact gut bacteria and if bacterial profiles predict intervention response. Design Sixty-seven patients with IBS were randomised to traditional IBS (n=34) or low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) (n=33) diets for 4 weeks. Food intake was recorded for 4 days during screening and intervention. Faecal samples and IBS Symptom Severity Score (IBS-SSS) reports were collected before (baseline) and after intervention. A faecal microbiota dysbiosis test (GA-map Dysbiosis Test) evaluated bacterial composition. Per protocol analysis was performed on 61 patients from whom microbiome data were available. Results Responders (reduced IBS-SSS by ≥50) to low FODMAP, but not traditional, dietary intervention were discriminated from non-responders before and after intervention based on faecal bacterial profiles. Bacterial abundance tended to be higher in non-responders to a low FODMAP diet compared with responders before and after intervention. A low FODMAP intervention was associated with an increase in Dysbiosis Index (DI) scores in 42% of patients; while decreased DI scores were recorded in 33% of patients following a traditional IBS diet. Non-responders to a low FODMAP diet, but not a traditional IBS diet had higher DI scores than responders at baseline. Finally, while a traditional IBS diet was not associated with significant reduction of investigated bacteria, a low FODMAP diet was associated with reduced Bifidobacterium and Actinobacteria in patients, correlating with lactose consumption. Conclusions A low FODMAP, but not a traditional IBS diet may have significant impact on faecal bacteria. Responsiveness to a low FODMAP diet intervention may be predicted by faecal bacterial profiles. Trial registration number NCT02107625.


Scandinavian Journal of Gastroenterology | 2012

Effects on gastrointestinal transit and antroduodenojejunal manometry after gut-directed hypnotherapy in irritable bowel syndrome (IBS)

Perjohan Lindfors; Hans Törnblom; Riadh Sadik; Einar Björnsson; Hasse Abrahamsson; Magnus Simren

Abstract Background. Gut-directed hypnotherapy is an effective treatment in irritable bowel syndrome (IBS) but little is known about the mechanisms of action. In this study we aimed to investigate the effects on gastrointestinal motility when treating IBS with gut-directed hypnotherapy. Methods. We randomized 90 patients with IBS, refractory to standard management to receive gut-directed hypnotherapy 1 h/week for 12 weeks or supportive treatment for the same time period. Eighty-one subjects (40 hypnotherapy, 41 controls) could be evaluated by one or more of the following investigations, both before and after the intervention: gastric emptying time, small bowel transit time, colonic transit time, and antroduodenojejunal manometry. Results. No significant differences in gastric emptying time, small bowel transit time, or colonic transit time was found when comparing the baseline and post-intervention measurements in the hypnotherapy group or in the control group. The same was true concerning the results of the antroduodenojejunal manometry. However, there was a numerical trend toward a higher number of migrating motor complexes at manometry and an accelerated gastric emptying time after hypnotherapy that did not reach statistical significance. Conclusions. In this study, we were not able to find evidence for long-standing effects on gastrointestinal motility as a mediator of the effects on IBS when treating the condition with gut-directed hypnotherapy. Further research to understand the mechanism of action is needed.


Journal of Consulting and Clinical Psychology | 2018

How does exposure therapy work? A comparison between generic and gastrointestinal anxiety–specific mediators in a dismantling study of exposure therapy for irritable bowel syndrome.

Hugo Hesser; Erik Hedman-Lagerlöf; Erik Andersson; Perjohan Lindfors; Brjánn Ljótsson

Objective: Systematic exposure is potentially an effective treatment procedure for treating irritable bowel syndrome (IBS), but little is known about the processes by which it achieves its effect on outcome. The aim of this study was to identify mediators in a previously published randomized dismantling trial in which participants with IBS were randomized to Internet-delivered cognitive–behavioral treatment (ICBT) that incorporated systematic exposure or to the same treatment protocol without exposure (ICBT-WE). Method: Weekly measurements of gastrointestinal anxiety–specific process variables (behavioral avoidance, gastrointestinal-specific anxiety) based on the gastrointestinal symptom–specific anxiety model, generic process variables (self-efficacy and mindful nonreactivity), and treatment outcome (IBS symptoms) were obtained from 309 participants with IBS. Growth models and cross-lagged panel models, estimated within structural equation modeling, were employed to evaluate mediators of outcome. Results: Parallel process growth modeling showed that behavioral avoidance, gastrointestinal-specific anxiety, self-efficacy mediated the incremental effect of ICBT compared to ICBT-WE. The mediated effect of avoidance was stronger for individuals scoring high on the avoidance variable at 1st measurement point. Cross-lagged regression analyses with random effects revealed that behavioral avoidance and gastrointestinal-specific anxiety had a stronger effect on subsequent symptom change rather than vice versa, whereas mindful nonreactivity and self-efficacy displayed the opposite pattern. Conclusions: The evidence collectively provided support for the hypothesis that exposure for IBS achieves its positive results by virtue of changing gastrointestinal anxiety–specific processes rather than generic processes. IBS-specific behavioral avoidance emerged as the most clear-cut mediator of the specific effect of exposure on outcome.


Psychological Medicine | 2017

The specific effect of systematic exposure in irritable bowel syndrome: complier average causal effect analysis using growth mixture modeling

Hugo Hesser; Erik Hedman; Perjohan Lindfors; Evelyn Andersson; Brjánn Ljótsson

BACKGROUND We reanalyzed data from a previously published randomized component study that aimed to test the incremental effect of systematic exposure in an internet-delivered cognitive behavioral treatment (ICBT) for irritable bowel syndrome (IBS). METHODS Three hundred and nine individuals with IBS were randomly assigned to either the full treatment protocol (experimental condition) or the same treatment protocol without systematic exposure (control). Participants were assessed weekly for IBS symptoms over the active treatment phase. We used a complier average causal effect (CACE) analysis, in the growth mixture modeling framework, to (1) examine the specific effect of exposure among those who received the intervention (i.e. compliers), and (2) explore the associations of pre-treatment patient characteristics with compliance status and outcome changes. RESULTS Fifty-five per cent of those assigned to the experimental condition were classified as compliers. The CACE analysis that took into account compliance status demonstrated that the magnitude of the incremental effect of systematic exposure on IBS symptoms was larger than the effect observed in an intention-to-treat analysis that ignored compliance status (d = 0.81 v. d = 0.44). Patients with university education showed more improvement during the exposure phase of the treatment. Pre-treatment patient characteristics did not predict compliance status. CONCLUSIONS The effect of systematic exposure on IBS symptoms is of substantial magnitude among those individuals who actually receive the intervention (CACE). Studying the subsample of individuals who discontinue treatment prematurely and tailoring interventions to improve compliance may increase overall improvement rates in ICBT for IBS.


Gastroenterology | 2015

Diet Low in FODMAPs Reduces Symptoms of Irritable Bowel Syndrome as Well as Traditional Dietary Advice: A Randomized Controlled Trial

Lena Böhn; Stine Störsrud; Therese M. Liljebo; Lena Collin; Perjohan Lindfors; Hans Törnblom; Magnus Simren

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Magnus Simren

University of Gothenburg

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Hans Törnblom

University of Gothenburg

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