Body mass index and response to a multidisciplinary treatment of fibromyalgia

Adults with excess weight or obesity, but not with overweight, report greater pain intensities than individuals with normal weight: a systematic review and meta-analysis

Context

Over 1.9 billion adult people have overweight or obesity. Considered as a chronic disease itself, obesity is associated with several comorbidities. Chronic pain affects approximately 60 million people and its connection with obesity has been displayed in several studies. However, controversial results showing both lower and higher pain thresholds in subjects with obesity compared to individuals with normal weight and the different parameters used to define such association (e.g., pain severity, frequency or duration) make it hard to draw straight forward conclusions in the matter. The objective of this article is to examine the relationship between overweight and obesity (classified with BMI as recommended by WHO) and self-perceived pain intensity in adults.

Methods

A literature search was conducted following PRISMA guidelines using the databases CINAHL, Cochrane Library, EMBASE, PEDro, PubMed, Scopus and Web of Science to identify original studies that provide BMI values and their associated pain intensity assessed by self-report scales. Self-report pain scores were normalized and pooled within meta-analyses. The Cochrane's Q test and I2 index were used to clarify the amount of heterogeneity; meta-regression was performed to explore the relationship between each outcome and the risk of bias.

Results

Of 2194 studies, 31 eligible studies were identified and appraised, 22 of which provided data for a quantitative analysis. The results herein suggested that adults with excess weight (BMI ≥ 25.0) or obesity (BMI ≥ 30.0) but not with overweight (pre-obesity) alone (BMI 25.0-29.9), are more likely to report greater intensities of pain than individuals of normal weight (BMI 18.5-24.9). Subgroup analyses regarding the pathology of the patients showed no statistically significant differences between groups. Also, influence of age in the effect size, evaluated by meta-regression, was only observed in one of the four analyses. Furthermore, the robustness of the findings was supported by two different sensitivity analyses.

Conclusion

Subjects with obesity and excess weight, but not overweight, reported greater pain intensities than individuals with normal weight. This finding encourages treatment of obesity as a component of pain management. More research is required to better understand the mechanisms of these differences and the clinical utility of the findings.

Systematic Review Registration

https://doi.org/10.17605/OSF.IO/RF2G3, identifier OSF.IO/RF2G3.

Predictors of Sustained Response to Functional Restoration in a Military Population

INTRODUCTION

The purpose of this study was to determine if improvement in pain impact and functional performance following a functional restoration (FR) program was sustained up to 6 months posttreatment and to identify predictors of sustained improvement.

MATERIALS AND METHODS

Secondary analysis of data collected during randomized clinical trial. Study population included 108 US active duty service members who completed an FR program, as well as 3- and/or 6-month follow-up assessments. Primary outcome measure was the NIH Research Task Force (pain) impact score (PIS). Secondary outcome was a composite functional performance measure of treadmill, lifting, and carrying tolerances. Variables analyzed to determine their predictive value included demographics; treatment hours; measures of pain intensity, function, mood, sleep, social satisfaction, pain catastrophizing, kinesiophobia, self-efficacy, pain acceptance, patient activation, functional performance, and neuropathic pain.

RESULTS

Mean PIS and functional performance improved significantly immediately following FR, but after 6 months, only improvement in functional performance sustained. Responder analysis showed that 6 months after FR, 42% of participants reported improvement that exceeded the minimal clinically important difference in PIS or functional performance. Predictors of sustained PIS improvement included younger age, absence of neuropathic pain features, less self-rated disability, better baseline functional performance, and worse baseline PIS. Predictors of sustained functional performance improvement included more treatment hours, lower baseline pain catastrophizing, and lower baseline functional performance.

CONCLUSIONS

This study supports the investment of treatment time in FR to yield sustained clinically meaningful improvement, as observed in over 40% of this study's military participants. Pretreatment predictors of sustained response included lower pain catastrophizing and absence of neuropathic pain. Further research is needed to determine if treatments that improve pain catastrophizing and neuropathic pain will result in sustained improvement in pain impact and functional performance following FR program participation.

Are OMERACT recommendations followed in clinical trials on fibromyalgia? A systematic review of patient-reported outcomes and their measures

PURPOSE

Patient-Reported Outcomes (PROs) and its measures (PROMs) are key to outcome assessment in Fibromyalgia (FM) trials. The aim of this review was to investigate which domains and instruments were assessed in recent FM trials and to compare them to recommendations by the Outcome Measures in Rheumatology (OMERACT) initiative. In addition, we investigated the overlap with a generic health assessment approach, i.e. eight domains suggested by the Patient-Reported Outcome Measurement Information System® (PROMIS®).

METHODS

In compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic literature search in scientific databases including PubMed, PsycInfo, and Embase was conducted to identify studies that assessed at least two dimensions of health-related quality of life (HRQoL) from 2015 to June 2022. Non-randomized and randomized controlled trials were included in the analysis. We extracted PROs and PROMs used in each study.

RESULTS

From 1845 identified records, 107 records out of 105 studies met the inclusion criteria. Studies investigated 50 PROs using 126 different PROMs. Most frequently assessed domains were pain, depression, fatigue, and anxiety (> 95% of the studies). The disease-specific FIQ was the most frequently applied PROM (82%). Overall, only 9% of the studies covered all domains deemed mandatory by OMERACT. Very few studies covered all eight generic health domains suggested by PROMIS.

CONCLUSION

The majority of trials covered most OMERACT domains or generic PROMIS health domains. There was, however, great variability in the instruments used to assess the domains, which points at a limited degree of standardization in the field.

Multidisciplinary rehabilitation treatments for patients with fibromyalgia: a systematic review

INTRODUCTION

Fibromyalgia (FM) is a pathology that causes physical, psychological, and social problems. For this reason, it requires treatment that involves all of these elements. The main of study is to examine multidisciplinary rehabilitation treatment (MRT) in fibromyalgia and to identify healthcare approaches developing effective MRT tools for the treatment of FM.

EVIDENCE ACQUISITION

In this systematic review, we searched the following databases: CINAHL, PubMed, Scopus, Cuidatge, Cuiden, ENFISPO, IBEC and IME.

EVIDENCE SYNTHESIS

Of 356 articles found we selected 13 to analyze and summarize. We created 4 different categories: 1) multidisciplinary rehabilitation treatment focusing on health education and cognitive behavioral therapy (CBT); 2) multidisciplinary rehabilitation treatment that includes dietetics; 3) multidisciplinary rehabilitation treatment adapted to the patients' characteristics; 4) multidisciplinary rehabilitation treatment based on physical exercise.

CONCLUSIONS

This review identifies the most effective treatments that may be usefully applied in many different rehabilitation contexts. These include all treatments that incorporated an education (ED) program to patients and an exercise program complete with aerobic exercise (AE), stretching (SE), relaxation (RE), strengthening (TE), endurance (EN), and which includes the entire body and biofeedback. Furthermore, many approaches also include cognitive behavioral therapy (CBT) for self-management such as occupational therapy, moderation, acceptance, commitment, motivation to change and forgiveness.

BMI but not age and sex negatively impact on the outcome of pharmacotherapy in fibromyalgia: a systematic review

INTRODUCTION

The impact of sex, age, body mass index (BMI) in fibromyalgia is still unclear. A systematic review was conducted to investigate whether sex, age and BMI influence the clinical outcomes and rate of adverse events.

METHODS

The present study was performed according to the PRISMA guidelines. The literature search was performed in February 2021. All the RCTs investigating pharmacological strategies for fibromyalgia were accessed.

RESULTS

Data from 51 RCTs (17,311 patients) were collected. Short Form 36 emotional, Social function and physical role subscales showed evidence of a negative association with BMI (P = 0.02, P = 0.002 and P = 0.0001, respectively). Depression and anxiety subscales of the Hospital Anxiety and Depression score demonstrated evidence of a positive association with age (P = 0.04 and P = 0.001, respectively) and sex (P = 0.00005 and P = 0.0001, respectively). Visual analog scale evidenced a positive association with BMI (P = 0.04). Clinical Global Impression Severity scale demonstrated evidence of a negative association with BMI (P = 0.02).

CONCLUSION

Irrespective from the pharmacological approach, a higher BMI is negatively associated with a favorable outcome in patients with fibromyalgia. The association with sex and age remains controversial.

LEVEL OF EVIDENCE

I, systematic review of RCTs.

The association between body mass index and fibromyalgia severity: data from a cross-sectional survey of 2339 patients

Objective

Various studies have shown that overweight and obesity are central features of FM, but the real impact of a high BMI on clinical severity in patients with FM is still controversial. The aim of this study was to analyse the relationships between BMI categories and measures of symptom severity and functional impairment using data from a Web-based registry of patients with FM.

Methods

Adult patients with an ACR 2010/2011 diagnosis of FM underwent a complete physical examination and laboratory tests and were asked to complete a package of questionnaires covering their sociodemographic and treatment details, in addition to the following disease-specific questionnaires: the revised Fibromyalgia Impact Questionnaire (FIQR), the modified Fibromyalgia Assessment Status questionnaire (ModFAS) and the Polysymptomatic Distress Scale (PDS).

Results

A total of 2339 patients were recruited and divided into two weight categories, underweight/normal (U/N, n = 1127, 48.2%) and overweight/obese (O/O, n = 1212, 51.8%). The total and subscales of FIQR, ModFAS and PSD scores were significantly higher in the O/O patients, as were all the mean scores of the individual FIQR items (P < 0.001 for all).

Conclusion

Our findings demonstrate that O/O patients with FM are significantly more impaired than U/N patients in all the symptomatological and functional domains as measured using the FIQR, ModFAS and PDS, thus suggesting that being O/O has an additional effect on symptoms and function.

Maintenance of quality of life improvement for patients with chronic pain and obesity after interdisciplinary multimodal pain rehabilitation - A study using the Swedish Quality Registry for Pain Rehabilitation

BACKGROUND

Throughout the world many people have both obesity and chronic pain, comorbidities that decrease Health-Related Quality of Life (HRQoL). It is uncertain whether patients with comorbid obesity can maintain improved HRQoL after Interdisciplinary Multimodal Pain Rehabilitation (IMMPR).

METHODS

Data from 2016, 2017, and 2018 were obtained from a national pain database for Swedish specialized pain clinics and collected at three time points: Pre-IMMPR; Post- IMMPR; and 12-month follow-up (FU-IMMPR). Participants (N = 872) reported body weight, height, pain aspects, and HRQoL (RAND 36-Item Health Survey). Severe obesity (Body Mass Index, BMI ≥35 kg/m² ) was defined according to WHO classifications. We used linear mixed regression models to examine BMI group differences in HRQoL over time.

RESULTS

More than 25% of patients (224/872) were obese and nearly 30% (63/224) of these were severely obese. All BMI groups improved significantly in both physical and mental composites of HRQoL after IMMPR (Pre- vs. Post-IMMPR, p < .001). The improvements were maintained at a 12-month follow-up (Post- vs. FU-IMMPR, p > .05). The severe obesity group had the lowest physical health score and least improvement (pre- vs. FU-IMMPR, Cohen's d = o.422, small effect size). Severe obesity had negative impact on physical health (β = -4.39, p < .05) after controlling for sociodemographic factors and pain aspects.

CONCLUSION

Improvements in HRQoL after IMMPR were achieved and maintained across all weights, including patients with comorbid obesity. Only severe obesity was negatively associated with physical health aspects of HRQoL.

SIGNIFICANCE

Patients with chronic pain and comorbid obesity achieve sustained Health-Related Quality of Life (HRQoL) improvements from Interdisciplinary Multimodal Pain Rehabilitation (IMMPR). This finding suggests that rehabilitation professionals should consider using IMMPR for patients with comorbid obesity even though their improvement may not reach the same level as for non-obese patients.

Aerobic exercise training for adults with fibromyalgia

BACKGROUND

Exercise training is commonly recommended for individuals with fibromyalgia. This review is one of a series of reviews about exercise training for people with fibromyalgia that will replace the "Exercise for treating fibromyalgia syndrome" review first published in 2002.

OBJECTIVES

• To evaluate the benefits and harms of aerobic exercise training for adults with fibromyalgia• To assess the following specific comparisons ० Aerobic versus control conditions (eg, treatment as usual, wait list control, physical activity as usual) ० Aerobic versus aerobic interventions (eg, running vs brisk walking) ० Aerobic versus non-exercise interventions (eg, medications, education) We did not assess specific comparisons involving aerobic exercise versus other exercise interventions (eg, resistance exercise, aquatic exercise, flexibility exercise, mixed exercise). Other systematic reviews have examined or will examine these comparisons (Bidonde 2014; Busch 2013).

SEARCH METHODS

We searched the Cochrane Library, MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Physiotherapy Evidence Database (PEDro), Thesis and Dissertation Abstracts, the Allied and Complementary Medicine Database (AMED), the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), and the ClinicalTrials.gov registry up to June 2016, unrestricted by language, and we reviewed the reference lists of retrieved trials to identify potentially relevant trials.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) in adults with a diagnosis of fibromyalgia that compared aerobic training interventions (dynamic physical activity that increases breathing and heart rate to submaximal levels for a prolonged period) versus no exercise or another intervention. Major outcomes were health-related quality of life (HRQL), pain intensity, stiffness, fatigue, physical function, withdrawals, and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials for inclusion, extracted data, performed a risk of bias assessment, and assessed the quality of the body of evidence for major outcomes using the GRADE approach. We used a 15% threshold for calculation of clinically relevant differences between groups.

MAIN RESULTS

We included 13 RCTs (839 people). Studies were at risk of selection, performance, and detection bias (owing to lack of blinding for self-reported outcomes) and had low risk of attrition and reporting bias. We prioritized the findings when aerobic exercise was compared with no exercise control and present them fully here.Eight trials (with 456 participants) provided low-quality evidence for pain intensity, fatigue, stiffness, and physical function; and moderate-quality evidence for withdrawals and HRQL at completion of the intervention (6 to 24 weeks). With the exception of withdrawals and adverse events, major outcome measures were self-reported and were expressed on a 0 to 100 scale (lower values are best, negative mean differences (MDs)/standardized mean differences (SMDs) indicate improvement). Effects for aerobic exercise versus control were as follows: HRQL: mean 56.08; five studies; N = 372; MD -7.89, 95% CI -13.23 to -2.55; absolute improvement of 8% (3% to 13%) and relative improvement of 15% (5% to 24%); pain intensity: mean 65.31; six studies; N = 351; MD -11.06, 95% CI -18.34 to -3.77; absolute improvement of 11% (95% CI 4% to 18%) and relative improvement of 18% (7% to 30%); stiffness: mean 69; one study; N = 143; MD -7.96, 95% CI -14.95 to -0.97; absolute difference in improvement of 8% (1% to 15%) and relative change in improvement of 11.4% (21.4% to 1.4%); physical function: mean 38.32; three studies; N = 246; MD -10.16, 95% CI -15.39 to -4.94; absolute change in improvement of 10% (15% to 5%) and relative change in improvement of 21.9% (33% to 11%); and fatigue: mean 68; three studies; N = 286; MD -6.48, 95% CI -14.33 to 1.38; absolute change in improvement of 6% (12% improvement to 0.3% worse) and relative change in improvement of 8% (16% improvement to 0.4% worse). Pooled analysis resulted in a risk ratio (RR) of moderate quality for withdrawals (17 per 100 and 20 per 100 in control and intervention groups, respectively; eight studies; N = 456; RR 1.25, 95%CI 0.89 to 1.77; absolute change of 5% more withdrawals with exercise (3% fewer to 12% more).Three trials provided low-quality evidence on long-term effects (24 to 208 weeks post intervention) and reported that benefits for pain and function persisted but did not for HRQL or fatigue. Withdrawals were similar, and investigators did not assess stiffness and adverse events.We are uncertain about the effects of one aerobic intervention versus another, as the evidence was of low to very low quality and was derived from single trials only, precluding meta-analyses. Similarly, we are uncertain of the effects of aerobic exercise over active controls (ie, education, three studies; stress management training, one study; medication, one study) owing to evidence of low to very low quality provided by single trials. Most studies did not measure adverse events; thus we are uncertain about the risk of adverse events associated with aerobic exercise.

AUTHORS' CONCLUSIONS

When compared with control, moderate-quality evidence indicates that aerobic exercise probably improves HRQL and all-cause withdrawal, and low-quality evidence suggests that aerobic exercise may slightly decrease pain intensity, may slightly improve physical function, and may lead to little difference in fatigue and stiffness. Three of the reported outcomes reached clinical significance (HRQL, physical function, and pain). Long-term effects of aerobic exercise may include little or no difference in pain, physical function, and all-cause withdrawal, and we are uncertain about long-term effects on remaining outcomes. We downgraded the evidence owing to the small number of included trials and participants across trials, and because of issues related to unclear and high risks of bias (performance, selection, and detection biases). Aerobic exercise appears to be well tolerated (similar withdrawal rates across groups), although evidence on adverse events is scarce, so we are uncertain about its safety.