Shared and distinct effect mediators in exposure-based and traditional cognitive behavior therapy for fibromyalgia: Secondary analysis of a randomized controlled trial

Fibromyalgia is a chronic pain condition associated with substantial suffering and societal costs. Traditional cognitive behavior therapy (T-CBT) is the most evaluated psychological treatment, but exposure therapy (Exp-CBT) has shown promise with a pronounced focus on the reduction of pain-related avoidance behaviors. In a recent randomized controlled trial (N = 274), we found that Exp-CBT was not superior to T-CBT (d = -0.10) in reducing overall fibromyalgia severity. This study investigated pain-related avoidance behaviors, pain catastrophizing, hypervigilance, pacing, overdoing and physical activity as potential mediators of the treatment effect. Mediation analyses were based on parallel process growth models fitted on 11 weekly measurement points, and week-by-week time-lagged effects were tested using random intercepts cross-lagged panel models. Results indicated that a reduction in avoidance behaviors, pain catastrophizing, and hypervigilance were significant mediators of change in both treatments. An increase in pacing and a reduction in overdoing were significant mediators in T-CBT only. Physical activity was not a mediator. In the time-lagged analyses, an unequivocal effect on subsequent fibromyalgia severity was seen of avoidance and catastrophizing in Exp-CBT, and of overdoing in T-CBT. Exposure-based and traditional CBT for fibromyalgia appear to share common treatment mediators, namely pain-related avoidance behavior, catastrophizing and hypervigilance.

Psychometric evaluation of the Pain Vigilance and Awareness Questionnaire (PVAQ) in fibromyalgia: Confirmatory factor analysis and the development of a Swedish 8-item version

BACKGROUND

Excessive attention to pain, or hypervigilance, is associated with negative outcomes in chronic pain conditions such as fibromyalgia. The Pain Vigilance and Awareness Questionnaire (PVAQ) is a self-report questionnaire to measure attention to pain. This study aimed to evaluate the psychometric properties of a Swedish version of the PVAQ.

METHODS

Psychometric evaluation on cross-sectional data derived from a clinical trial for fibromyalgia (N = 274). We evaluated item characteristics, factor structure in a confirmatory factor analytic framework, internal consistency, and construct validity in terms of correlations with other clinical variables.

RESULTS

Though confirmatory factor analysis did not result in a satisfactory solution for the full 16-item scale, acceptable two-factor solutions could be based on either nine or eight items (the PVAQ-9 and PVAQ-8). Internal consistency for both the PVAQ-9 and PVAQ-8 were good to excellent, and associations with pain catastrophizing, anxiety, depression, disability, and overall fibromyalgia impact were largely supportive of construct validity. An unexpected result was that, contrary to previous findings, no version of the PVAQ correlated consistently with pain intensity.

CONCLUSIONS

The Swedish PVAQ-9 and PVAQ-8 appear to have acceptable psychometric properties when administered online to individuals with fibromyalgia. The PVAQ-8 may be preferable due to being shorter and including an equal number of items per factor. Replication is warranted.

SIGNIFICANCE

This study evaluated the psychometric properties of a Swedish translation of the PVAQ in individuals with fibromyalgia. No convincing factor structure was found for the 16-item version. We could, however, confirm the factor structure of an established 9-item version (the PVAQ-9), and recommend further use of a new 8-item version (the PVAQ-8). In summary, the PVAQ exhibited more convincing psychometric properties when the number of items was roughly cut in half.

Trajectories of mental health outcomes following COVID-19 infection: a prospective longitudinal study

BACKGROUND

The COVID-19 pandemic has triggered a global mental health crisis. Yet, we know little about the lasting effects of COVID-19 infection on mental health. This prospective longitudinal study aimed to investigate the trajectories of mental health changes in individuals infected with COVID-19 and to identify potential predictors that may influence these changes.

METHODS

A web-survey that targeted individuals that had been infected with COVID-19 was used at three time-points: T0 (baseline), T1 (six months), and T2 (twelve months). The survey included demographics, questions related to COVID-19 status, previous psychiatric diagnosis, post-COVID impairments, fatigue, and standardized measures of depression, anxiety, insomnia. Linear mixed models were used to examine changes in depression, anxiety, and insomnia over time and identify factors that impacted trajectories of mental health outcomes.

RESULTS

A total of 236 individuals completed assessments and was included in the longitudinal sample. The participants' age ranged between 19 and 81 years old (M = 48.71, SD = 10.74). The results revealed notable changes in mental health outcomes over time. The trajectory of depression showed significant improvement over time while the trends in anxiety and insomnia did not exhibit significant changes over time. Younger participants and individuals who experienced severe COVID-19 infection in the acute phase were identified as high-risk groups with worst mental ill-health. The main predictors of the changes in the mental health outcomes were fatigue and post-COVID impairments.

CONCLUSIONS

The findings of our study suggest that mental health outcomes following COVID-19 infection exhibit a dynamic pattern over time. The study provides valuable insights into the mental health trajectory following COVID-19 infection, emphasizing the need for ongoing assessment, support, and interventions tailored to the evolving mental health needs of this population.

Cognitive behavior therapy for adult eating disorders in routine clinical care: A systematic review and meta-analysis

OBJECTIVE

Cognitive behavior therapy (CBT) is a recommended treatment for eating disorders (ED) in adults given its evidence, mainly based on efficacy studies. However, little is known about how CBT works in routine clinical care. The goal of the present meta-analysis is to investigate how CBT works for various ED when carried out in routine clinical settings.

METHOD

Ovid MEDLINE, Embase OVID, and PsycINFO were systematically searched for articles published until June 2023. The outcome of CBT, methodological quality, risk of bias (RoB), and moderators of treatment outcome were examined and benchmarked by meta-analytically comparing with efficacy studies for ED. Fifty studies comprising 4299 participants who received CBT were included.

RESULTS

Large within-group effect sizes (ES) were obtained for ED-psychopathology at post-treatment (1.12), and follow-up (1.22), on average 9.9 months post-treatment. Attrition rate was 25.5% and RoB was considerable in the majority of studies. The benchmarking analysis showed that effectiveness studies had very similar ESs as efficacy studies (1.20 at post-treatment and 1.28 at follow-up).

CONCLUSION

CBT for ED is an effective treatment when delivered in routine clinical care, with ESs comparable to those found in efficacy studies. However, the evidence needs to be interpreted with caution due to the RoB in a high proportion of studies.

PUBLIC SIGNIFICANCE

Eating disorders are common in the population and often lead to multiple negative consequences. CBT has been found effective for ED and is recommended in clinical guidelines. Since these recommendations are primarily based on university studies we wanted to investigate how CBT performs in routine clinical care. Our meta-analysis found that CBT worked as well in routine care as in university setting studies.

Effect of exposure-based vs traditional cognitive behavior therapy for fibromyalgia: a two-site single-blind randomized controlled trial

ABSTRACT

Fibromyalgia is a debilitating pain condition for which treatment effects are typically modest. The most evaluated psychological treatment is traditional cognitive behavior therapy (T-CBT), but promising effects have recently been seen in exposure-based cognitive behavior therapy (Exp-CBT). We investigated whether Exp-CBT was superior to T-CBT in a randomized controlled trial. Self-referred participants with fibromyalgia (N = 274) were randomized (1:1) to 10 weeks of Exp-CBT or T-CBT. Treatments were delivered online and presented as "CBT for fibromyalgia." Participants were assessed at baseline, weekly during treatment, posttreatment, and at 6- and 12-month follow-up. Primary outcome was the difference in reduction in fibromyalgia severity as measured using the Fibromyalgia Impact Questionnaire (FIQ) over 11 assessment points from baseline to posttreatment, modelled within an intention-to-treat framework using linear mixed effects models fitted on multiple imputed data. Approximately 91% of weekly FIQ scores were collected over the main phase. There was no significant difference between Exp-CBT and T-CBT in the mean reduction of fibromyalgia severity from pretreatment to posttreatment (b = 1.3, 95% CI -3.0 to 5.7, P = 0.544, d = -0.10). Minimal clinically important improvement was seen 60% in Exp-CBT vs 59% in T-CBT. Effects were sustained up to 12 months posttreatment. This well-powered randomized trial indicated that Exp-CBT was not superior to T-CBT for fibromyalgia. Both treatments were associated with a marked reduction in fibromyalgia severity, and the online treatment format might be of high clinical utility. T-CBT can still be regarded a reference standard treatment that remains clinically relevant when compared to novel treatment approaches.

Effect moderators in Internet-based exposure therapy for fibromyalgia: The role of pain intensity

BACKGROUND

A recent randomized controlled trial (N = 140) was indicative of large and sustained average improvements of Internet-based exposure for fibromyalgia, as compared to a waitlist. However, little is known about who benefits the most from this treatment.

OBJECTIVES

To test for potential moderating effects of age, educational attainment, the duration of fibromyalgia, baseline overall fibromyalgia severity, pain intensity, fibromyalgia-related avoidance behaviour and symptom preoccupation on the waitlist-controlled effect of 10 weeks of Internet-based exposure for fibromyalgia.

METHODS

Secondary analysis of a randomized controlled trial (ClinicalTrials.gov NCT02638636). We used linear mixed effects models to determine whether the waitlist-controlled effect of exposure therapy on overall fibromyalgia severity (Fibromyalgia Impact Questionnaire) differed as a function of the potential moderators.

RESULTS

Only pain intensity (0-10) was found to be a significant moderator, where a higher baseline pain intensity predicted a more limited waitlist-controlled effect of Internet-based exposure (B = 3.48, 95% CI: 0.84-6.13). Standardized point estimates of effects were small for the sociodemographic variables, and in the moderate range for some clinical variables that did not reach statistical significance such as behavioural avoidance and time with the fibromyalgia diagnosis.

CONCLUSIONS

Results suggest that Internet-based exposure treatment was more useful for participants with lower baseline levels of pain, and less so for participants with higher baseline levels of pain. The treatment had relatively similar effects across the other tested moderators.

SIGNIFICANCE

This study evaluated potential effect moderators in exposure-based treatment for fibromyalgia. Results indicated that a higher level of pain intensity at baseline was predictive of a less favourable outcome. It may be extra important to monitor progression for these patients and to provide additional therapeutic support when needed.

Isolation and worry in relation to gambling and onset of gambling among psychiatry patients during the COVID-19 pandemic: A mediation study

When the COVID-19 pandemic started spreading globally, there was a fear that addictive behaviors would increase due to changes in everyday life caused by restrictions due to COVID-19. Studies were carried out to explore if this was true for gambling, typically revealing no overall increase in gambling behavior, although individuals who had previous experience with gambling problems were more likely to increase gambling during the pandemic. However, these studies only included individuals with previous gambling problems. It remains unknown whether other vulnerable groups, such as individuals with common mental disorders increased their gambling. This study aimed to explore the level of gambling problems among individuals with a history of mental disorders, namely, (i) pre-pandemic gamblers and (ii) pandemic-onset gamblers. Furthermore, we explored if worry and isolation mediate gambling and problem gambling. The data were analyzed using descriptive statistics and a structural equation model to investigate mediation. The results showed a high prevalence of at-risk and problem gambling in both groups. The pre-pandemic gamblers had a high level of at-risk and problem gambling. Furthermore, the individuals that started to gamble during the pandemic had an even higher degree of at-risk and problem gambling. The mediation showed that the onset of gambling was linked with the worry of COVID-infection and that worry predicted the level of gambling problems. This study highlights that vulnerability factors, isolation, and worry can be triggers for individuals with common mental disorders to engage in gambling as well as the importance of screening this population for gambling problems.

The 14-item short health anxiety inventory (SHAI-14) used as a screening tool: appropriate interpretation and diagnostic accuracy of the Swedish version

BACKGROUND

The 14-item Short Health Anxiety Inventory (SHAI-14) is a common measure of health anxiety but its screening properties have not been studied. The aims of this study were to evaluate the SHAI-14 as a screening instrument, identify cut-offs for clinically significant health anxiety and investigate which scores correspond to different severity levels.

METHOD

The study included 1729 psychiatric patients and 85 healthy controls. Participants completed the SHAI-14 and underwent a diagnostic interview. Cut-off scores were evaluated in three scenarios to approximate screening 1) in a psychiatric clinic, 2) in a low prevalence setting and, 3) of healthy volunteers (cut-off for remission). Receiver operating characteristics were used. Classification of severity was based on the distribution of SHAI-14 scores reported by patients with clinically significant health anxiety.

RESULTS

The area under the curve (AUC) values were high in all scenarios (above 0.95). The optimal cut-off scores on the SHAI-14 were 22 in the psychiatric context, 29 in a setting with low prevalence of psychiatric disorders and 18 versus healthy controls. SHAI-14 scores of 0-27 represented no or mild health anxiety, 28-32 moderate health anxiety and 33-42 substantial health anxiety.

CONCLUSION

Brief self-report measures used as screening instruments are a simple way of gathering information about the presence of specific symptoms and thus a way to detect the likelihood of a diagnosis. The SHAI-14 shows evidence of good diagnostic utility in both clinical and non-clinical settings. However, which cut-off score is to be used, depends on the intended purpose and the setting where the cut-off is used.

Mental health in individuals with self-reported psychiatric symptoms during the COVID-19 pandemic: Baseline data from a swedish longitudinal cohort study

OBJECTIVE

Individuals with psychiatric disorders may be both vulnerable and sensitive to rapid societal changes that have occurred during the COVID-19 pandemic. To fully understand these impacts, repeated measurements of these individuals are warranted. The current longitudinal study set out to perform monthly assessment of individuals with common psychiatric disorders using established questionnaires with a possibility for them to self- rate their symptoms, over time.

METHODS

Recruitment of individuals who identified themselves as struggling with mental health problems, living in Sweden between July 2020 and June 2021 using an online survey. The individuals answered questions on demographics, psychiatric history, current psychiatric symptoms (e.g., Patient Health Questionnaire, PHQ-9; General Anxiety Disorder, GAD-7), somatic health, health-care contacts and any changes therein during the pandemic. Monthly, longitudinal assessments are still ongoing (consenting participants provide data for 1 year), and here we present descriptive statistics from the baseline measurement. All measurements from baseline (>400 items), and follow-ups are presented in detail.

RESULTS

A total of 6.095 participants (average age 35 years) submitted complete baseline data. Marital status (43% single) and number of years of education (48% highest degree being high school) were evenly distributed in this population. The most common lifetime psychiatric disorder in the sample was depressive disorder (80.5%) and generalized anxiety disorder (45.9%), with a substantial proportion having severe symptoms of depression. (30.5%) and anxiety (37.1%). Lifetime suicidal ideation (75.0%) and non-suicidal self-harm (57.7%) were prevalent in the group and 14.5% reported drug use during the pandemic. Allergies (36.8%) were the most common somatic condition, followed by irritable bowel syndrome (18.7%). For those having experienced a traumatic event, 39% showed symptoms during the pandemic indicating PTSD. Regarding contact with mental health services during the pandemic, 22% had established a new contact, and 20% reported to have increased their psychiatric medication compared to before the pandemic.

CONCLUSION

Baseline data collected during the pandemic from individuals in Sweden with pre-existing psychiatric disorders demonstrate that this sample represents a population suitable for an investigation on the long-term impact of the pandemic, as intended by the longitudinal investigation that is ongoing. Follow-up questionnaires over a 12-month period are being collected and will indicate how the health and well-being of this population was impacted during the changes and uncertainties that have been characteristic of the past 2 years.

Targeting excessive worry with internet-based extinction therapy: a randomised controlled trial with mediation analysis and economical evaluation

BACKGROUND

Excessive worry is a common phenomenon. Our research group has previously developed an online intervention for excessive worry based on operant principles of extinction (IbET; internet-based extinction therapy) and tested it against a waiting-list. The aim of this study was to evaluate IbET against an active control comparator (CTRL).

METHODS

A 10-week parallel participant blind randomised controlled trial with health-economical evaluation and mediation analyses. Participants (N = 311) were randomised (ratio 4.5:4.5:1) to IbET, to CTRL (an internet-based stress-management training program) or to waiting-list. The nation-wide trial included self-referred adults with excessive worry. The primary outcome was change in worry assessed with the Penn State Worry Questionnaire from baseline to 10 weeks.

RESULTS

IbET had greater reductions in worry compared to CTRL [-3.6 point difference, (95% CI -2.4 to -4.9)] and also a significantly larger degree of treatment responders [63% v. 51%; risk ratio = 1.24 (95% CI 1.01-1.53)]. Both IbET and CTRL made large reductions in worry compared to waiting-list and effects were sustained up to 1 year. Treatment credibility, therapist attention, compliance and working alliance were equal between IbET and CTRL. Data attrition was 4% at the primary endpoint. The effects of IbET were mediated by the hypothesized causal mechanism (reduced thought suppression) but not by competing mediators. Health-economical evaluation indicated that IbET had a 99% chance of being cost-effective compared to CTRL given societal willingness to pay of 1000€.

CONCLUSIONS

IbET is more effective than active comparator to treat excessive worry. Replication and extensions to real-world setting are warranted.

Effect of Internet vs Face-to-Face Cognitive Behavior Therapy for Health Anxiety: A Randomized Noninferiority Clinical Trial

IMPORTANCE

Health anxiety is a common and often chronic mental health problem associated with distress, substantial costs, and frequent attendance throughout the health care system. Face-to-face cognitive behavior therapy (CBT) is the criterion standard treatment, but access is limited.

OBJECTIVE

To test the hypothesis that internet-delivered CBT, which requires relatively little resources, is noninferior to face-to-face CBT in the treatment of health anxiety.

DESIGN, SETTING, AND PARTICIPANTS

This randomized noninferiority clinical trial with health economic analysis was based at a primary care clinic and included patients with a principal diagnosis of health anxiety who were self-referred or referred from routine care. Recruitment began in December 10, 2014, and the last treatment ended on July 23, 2017. Follow-up data were collected up to 12 months after treatment. Analysis began October 2017 and ended March 2020.

INTERVENTIONS

Patients were randomized (1:1) to 12 weeks of internet-delivered CBT or to individual face-to-face CBT.

MAIN OUTCOMES AND MEASURES

Change in health anxiety symptoms from baseline to week 12. Analyses were conducted from intention-to-treat and per-protocol (completers only) perspectives, using the noninferiority margin of 2.25 points on the Health Anxiety Inventory, which has a theoretical range of 0 to 54.

RESULTS

Overall, 204 patients (mean [SD] age, 39 [12] years; 143 women [70%]) contributed with 2386 data points on the Health Anxiety Inventory over the treatment period. Of 204 patients, 102 (50%) were randomized to internet-delivered CBT, and 102 (50%) were randomized to face-to-face CBT. The 1-sided 95% CI upper limits for the internet-delivered CBT vs face-to-face CBT difference in change were within the noninferiority margin in the intention-to-treat analysis (B = 0.00; upper limit: 1.98; Cohen d = 0.00; upper limit: 0.23) and per-protocol analysis (B = 0.01; upper limit: 2.17; Cohen d = 0.00; upper limit: 0.25). The between-group effect was not moderated by initial symptom level, recruitment path, or patient treatment preference. Therapists spent 10.0 minutes per patient per week in the online treatment vs 45.6 minutes for face-to-face CBT. The net societal cost was lower in the online treatment (treatment period point difference: $3854). There was no significant group difference in the number of adverse events, and no serious adverse event was reported.

CONCLUSIONS AND RELEVANCE

In this trial, internet-delivered CBT appeared to be noninferior to face-to-face CBT for health anxiety, while incurring lower net societal costs. The online treatment format has potential to increase access to evidence-based treatment for health anxiety.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02314065.

Symptom Preoccupation in Fibromyalgia: Prevalence and Correlates of Somatic Symptom Disorder in a Self-Recruited Sample

BACKGROUND

Somatic symptom disorder (SSD) is characterized by a persistent and distressing psychological reaction to somatic symptoms. In pain disorders, the preoccupation with physical symptoms is associated with poor long-term outcomes. SSD may therefore be of use to identify and help chronic pain patients with particular needs.

OBJECTIVE

To test the hypothesis that in fibromyalgia, SSD is associated with higher anxiety sensitivity, health anxiety, and reactivity to pain, in addition to lower nonreactivity to inner experiences. In addition, to investigate if individuals with SSD report a larger impact of fibromyalgia core symptoms, more somatic symptoms, and higher psychiatric comorbidity.

METHODS

Using data from a clinical trial involving self-referred individuals with fibromyalgia, we compared participants with SSD to participants without SSD using t-tests and logistic regression.

RESULTS

Forty-nine out of 140 participants (35%) had SSD. Most findings corroborate that individuals with fibromyalgia who also meet criteria for SSD are worse off in terms of traits previously found to be predictive of a poor course in pain disorders. Post hoc analyses indicated that this could not be explained merely by a higher level of fibromyalgia core symptoms.

CONCLUSION

SSD appears to be associated with a higher symptom burden in fibromyalgia, but further research is needed to draw firm conclusions regarding the reliability, acceptability, and utility of the SSD diagnosis in the clinic.

Approach as a key for success: Reduced avoidance behaviour mediates the effect of exposure therapy for fibromyalgia

Fibromyalgia (FM) is a prevalent chronic pain disorder associated with large suffering and substantial societal costs. Pain-related avoidance behaviour and hypervigilance to bodily symptoms are common in FM and contribute in maintaining and exacerbating the disorder. Exposure therapy targeting avoidance behaviours and hypervigilance has shown promise in the treatment of FM. The present study investigated mediators of treatment outcome in exposure therapy for FM. We used data from a randomised trial, where 140 participants were allocated to 10-week internet-delivered exposure therapy or to a waiting-list control condition. The main outcome variable (FM symptoms) and the hypothesized mediators (FM-related avoidance behaviour, mindful non-reactivity and FM-related worry) were measured weekly throughout treatment. Mediation analyses were conducted using linear mixed effects models with bootstrap replication and time-lagged analysis. Results indicated that all three process variables were significant mediators of FM severity. However, in the time-lagged analyses, only FM-related avoidance behaviour displayed a unidirectional relationship over time with FM symptoms, suggesting a causal effect. Thus, results illustrate that changes in avoidance behaviour mediate the outcome of exposure on FM symptoms, which implies that avoidance behaviour is an important treatment target in exposure therapy.

Cognitive behaviour therapy for depression in primary care: systematic review and meta-analysis

Depression is common in primary care, and most patients prefer psychological treatment over pharmacotherapy. Cognitive behaviour therapy (CBT) is an effective treatment, but there are gaps in current knowledge about CBT in the primary care context, especially with regard to long-term effects and the efficacy of specific delivery formats. This is an obstacle to the integration of primary care and specialist psychiatry. We conducted a systematic review and meta-analysis of randomised controlled trials of CBT for primary care patients with depression to investigate the effect of CBT for patients with depression in primary care. A total of 34 studies, with 2543 patients in CBT and 2815 patients in control conditions, were included. CBT was more effective than the control conditions [g = 0.22 (95% confidence interval (CI) 0.15-0.30)], and the effect was sustained at follow-up [g = 0.17 (95% CI 0.10-0.24)]. CBT also led to a higher response rate [odds ratio (OR) = 2.47 (95% CI 1.60-3.80)] and remission rate [OR = 1.56 (95% CI 1.15-2.14)] than the control conditions. Heterogeneity was moderate. The controlled effect of CBT was significant regardless of whether patients met diagnostic criteria for depression, scored above a validated cut-off for depression, or merely had depressive symptoms. CBT also had a controlled effect regardless of whether the treatment was delivered as individual therapy, group therapy or therapist-guided self-help. We conclude that CBT appears to be effective for patients with depression in primary care, and recommend that patients with mild to moderate depression be offered CBT in primary care.

The empirical support for mindfulness-based interventions for common psychiatric disorders: a systematic review and meta-analysis

Mindfulness-based interventions (MBIs) have become widely used for common mental disorders (CMDs) but the state of the evidence has not been sufficiently investigated. The aims for this study were: (1) to quantify the effect size of MBIs for CMDs in the acute phase; (2) to explore moderator variables; and (3) to evaluate the evidence status of MBIs for the CMDs it has been tried for. A comprehensive systematic review and meta-analysis of randomized controlled trials (RCTs) were conducted. RCTs that evaluated MBI and included patients with a primary manifest CMD was included. Methodological quality, the risk of bias, publication bias and evidence status were assessed. Literature searches gave 2448 hits and 19 studies were included. MBIs were more effective than no treatment (g = 1.07) and treatment-as-usual (g = 0.40) but not in comparison to placebo (g = 0.17) or other active treatments (g = -0.01). Methodological quality was negatively correlated with outcome. For all psychiatric disorders it has been tested, MBIs were judged to have weak or no empirical support. The conclusion of the study is that the evidence-base for MBIs for CMDs in the acute phase is weak.

Cost-Effectiveness and Cost-Utility of Internet-Delivered Exposure Therapy for Fibromyalgia: Results From a Randomized, Controlled Trial

Fibromyalgia (FM) is a prevalent and debilitating chronic pain disorder associated with a substantial economic burden. Although there are several studies investigating the effectiveness of psychological treatments such as cognitive-behavioral therapy for FM, studies on cost-effectiveness are scarce. The aim of the present study was to investigate the cost-effectiveness of Internet-delivered exposure therapy (iExp) for FM. We used health economic data from a recently conducted randomized, controlled trial, where 140 participants were randomized to either iExp or a waitlist control (WLC) condition. Economic data were collected at pre-treatment, post-treatment, and at the 1-year follow-up. Treatment effectiveness in relation to costs were analyzed using both a societal perspective (including all direct and indirect costs) and a health care unit perspective (including only the direct treatment costs). Bootstrapped net benefit regression analyses were also conducted, comparing the difference in costs and effects between iExp and WLC, within different willingness-to-pay scenarios. Results showed that the incremental cost-effectiveness ratio was -$15,295, indicating that iExp was highly cost-effective as each successfully treated case (treatment responder) was associated with a substantial net reduction in costs. The robustness of the results was tested in 2 different sensitivity analyses, where iExp remained cost-effective, even in a willingness-to-pay-scenario of $0. We conclude that iExp is a cost-effective treatment that generates large societal cost savings. PERSPECTIVE: Health-economic evaluations of psychological interventions for FM are scarce. This study is a cost-effectiveness analysis of Internet-delivered exposure therapy for patients with FM. Results showed that iExp was highly cost-effective compared with no treatment, where each successfully treated case generated a substantial societal cost saving.