EULAR revised recommendations for the management of fibromyalgia

Opioids for Chronic Noncancer Pain: A Systematic Review and Meta-analysis

IMPORTANCE

Harms and benefits of opioids for chronic noncancer pain remain unclear.

OBJECTIVE

To systematically review randomized clinical trials (RCTs) of opioids for chronic noncancer pain.

DATA SOURCES AND STUDY SELECTION

The databases of CENTRAL, CINAHL, EMBASE, MEDLINE, AMED, and PsycINFO were searched from inception to April 2018 for RCTs of opioids for chronic noncancer pain vs any nonopioid control.

DATA EXTRACTION AND SYNTHESIS

Paired reviewers independently extracted data. The analyses used random-effects models and the Grading of Recommendations Assessment, Development and Evaluation to rate the quality of the evidence.

MAIN OUTCOMES AND MEASURES

The primary outcomes were pain intensity (score range, 0-10 cm on a visual analog scale for pain; lower is better and the minimally important difference [MID] is 1 cm), physical functioning (score range, 0-100 points on the 36-item Short Form physical component score [SF-36 PCS]; higher is better and the MID is 5 points), and incidence of vomiting.

RESULTS

Ninety-six RCTs including 26 169 participants (61% female; median age, 58 years [interquartile range, 51-61 years]) were included. Of the included studies, there were 25 trials of neuropathic pain, 32 trials of nociceptive pain, 33 trials of central sensitization (pain present in the absence of tissue damage), and 6 trials of mixed types of pain. Compared with placebo, opioid use was associated with reduced pain (weighted mean difference [WMD], -0.69 cm [95% CI, -0.82 to -0.56 cm] on a 10-cm visual analog scale for pain; modeled risk difference for achieving the MID, 11.9% [95% CI, 9.7% to 14.1%]), improved physical functioning (WMD, 2.04 points [95% CI, 1.41 to 2.68 points] on the 100-point SF-36 PCS; modeled risk difference for achieving the MID, 8.5% [95% CI, 5.9% to 11.2%]), and increased vomiting (5.9% with opioids vs 2.3% with placebo for trials that excluded patients with adverse events during a run-in period). Low- to moderate-quality evidence suggested similar associations of opioids with improvements in pain and physical functioning compared with nonsteroidal anti-inflammatory drugs (pain: WMD, -0.60 cm [95% CI, -1.54 to 0.34 cm]; physical functioning: WMD, -0.90 points [95% CI, -2.69 to 0.89 points]), tricyclic antidepressants (pain: WMD, -0.13 cm [95% CI, -0.99 to 0.74 cm]; physical functioning: WMD, -5.31 points [95% CI, -13.77 to 3.14 points]), and anticonvulsants (pain: WMD, -0.90 cm [95% CI, -1.65 to -0.14 cm]; physical functioning: WMD, 0.45 points [95% CI, -5.77 to 6.66 points]).

CONCLUSIONS AND RELEVANCE

In this meta-analysis of RCTs of patients with chronic noncancer pain, evidence from high-quality studies showed that opioid use was associated with statistically significant but small improvements in pain and physical functioning, and increased risk of vomiting compared with placebo. Comparisons of opioids with nonopioid alternatives suggested that the benefit for pain and functioning may be similar, although the evidence was from studies of only low to moderate quality.

Facts and myths pertaining to fibromyalgia

Fibromyalgia (FM) is characterized by chronic widespread pain, unrefreshing sleep, physical exhaustion, and cognitive difficulties. It occurs in all populations throughout the world, with prevalence between 2% and 4% in general populations. Definition, pathogenesis, diagnosis, and treatment of FM remain points of contention, with some even contesting its existence. The various classification systems according to pain medicine, psychiatry, and neurology (pain disease; persistent somatoform pain disorder; masked depression; somatic symptom disorder; small fiber neuropathy; brain disease) mostly capture only some components of this complex and heterogeneous disorder. The diagnosis can be established in most cases by a general practitioner when the symptoms meet recognized criteria and a somatic disease sufficiently explaining the symptoms is excluded. Evidence-based interdisciplinary guidelines give a strong recommendation for aerobic exercise and cognitive behavioral therapies. Drug therapy is not mandatory. Only a minority of patients experience substantial symptom relief with duloxetine, milnacipran, and pregabalin.

Efficacy of Low-Dose Amitriptyline for Chronic Low Back Pain: A Randomized Clinical Trial

IMPORTANCE

Antidepressants at low dose are commonly prescribed for the management of chronic low back pain and their use is recommended in international clinical guidelines. However, there is no evidence for their efficacy.

OBJECTIVE

To examine the efficacy of a low-dose antidepressant compared with an active comparator in reducing pain, disability, and work absence and hindrance in individuals with chronic low back pain.

DESIGN, SETTING, AND PARTICIPANTS

A double-blind, randomized clinical trial with a 6-month follow-up of adults with chronic, nonspecific, low back pain who were recruited through hospital/medical clinics and advertising was carried out.

INTERVENTION

Low-dose amitriptyline (25 mg/d) or an active comparator (benztropine mesylate, 1 mg/d) for 6 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was pain intensity measured at 3 and 6 months using the visual analog scale and Descriptor Differential Scale. Secondary outcomes included disability assessed using the Roland Morris Disability Questionnaire and work absence and hindrance assessed using the Short Form Health and Labour Questionnaire.

RESULTS

Of the 146 randomized participants (90 [61.6%] male; mean [SD] age, 54.8 [13.7] years), 118 (81%) completed 6-month follow-up. Treatment with low-dose amitriptyline did not result in greater pain reduction than the comparator at 6 (adjusted difference, -7.81; 95% CI, -15.7 to 0.10) or 3 months (adjusted difference, -1.05; 95% CI, -7.87 to 5.78), independent of baseline pain. There was no statistically significant difference in disability between the groups at 6 months (adjusted difference, -0.98; 95% CI, -2.42 to 0.46); however, there was a statistically significant improvement in disability for the low-dose amitriptyline group at 3 months (adjusted difference, -1.62; 95% CI, -2.88 to -0.36). There were no differences between the groups in work outcomes at 6 months (adjusted difference, absence: 1.51; 95% CI, 0.43-5.38; hindrance: 0.53; 95% CI, 0.19-1.51), or 3 months (adjusted difference, absence: 0.86; 95% CI, 0.32-2.31; hindrance: 0.78; 95% CI, 0.29-2.08), or in the number of participants who withdrew owing to adverse events (9 [12%] in each group; χ2 = 0.004; P = .95).

CONCLUSIONS AND RELEVANCE

This trial suggests that amitriptyline may be an effective treatment for chronic low back pain. There were no significant improvements in outcomes at 6 months, but there was a reduction in disability at 3 months, an improvement in pain intensity that was nonsignificant at 6 months, and minimal adverse events reported with a low-dose, modest sample size and active comparator. Although large-scale clinical trials that include dose escalation are needed, it may be worth considering low-dose amitriptyline if the only alternative is an opioid.

TRIAL REGISTRATION

anzctr.org.au Identifier: ACTRN12612000131853.

The effect of cryotherapy on fibromyalgia: a randomised clinical trial carried out in a cryosauna cabin

Evidence of symptomatic treatment for fibromyalgia (FM) is very low. Whole body cryotherapy (WBC) modulates different neurotransmitters, which might have a role in pain alleviation and could exert an effect on FM. Our aim was to evaluate the efficacy of WBC for the control of pain and impact of disease in FM. For this we run an open, randomized, crossover trial of Cryosense TCT™ cabin vs rest. Patients with FM according to ACR criteria were recruited consecutively from general practices. Trial endpoints were change (∆) in pain after 2 and 4 weeks, measured by a visual analogue scale (VAS), ∆ burden of disease, evaluated by the Fibromyalgia Impact Questionnaire (FIQ), and severity of FM, measured by the Combined Index of Severity of Fibromyalgia (ICAF). Within group differences, sequence and period effects were tested with Student's t or Mann-Whitney U tests. Multiple linear regression models were used to adjust effect by baseline differences between groups. Sixty patients were included in the trial. A period effect was noted, with residual effect of WBC; therefore, only results from the first sequence were analysed. ∆VAS pain, ∆FIQ and ∆ICAF scores were significantly larger in the WBC group after the first period (3.0 vs 0.3 in ∆VAS pain; 32.1 vs 0.4 in ∆FIQ; 13.7 vs 0.07 in ∆ICAF; all p < 0.001), and were confirmed after adjustment. In conclusion, WBC with a Cryosense TCT cabin may be a useful adjuvant therapy for FM; further studies on long-term effect and compared to other physical therapies are warranted.Trial registration NCT03425903.

Fibromyalgia in Primary Care

Fibromyalgia is a common disorder and has substantial impact on quality of life. The cause remains unknown, but current evidence points to multifactorial involvement of pain processing. Clinical diagnosis is aided by evidence-based diagnostic criteria with subscores for widespread pain and symptom severity. Nonpharmacologic treatments, including cognitive behavioral therapy, sleep hygiene, and regular aerobic exercise, form the cornerstone of management. Pharmacologic intervention is an important adjunct, but benefit is variable. There is no cure for fibromyalgia at this time, but persistence and patience in management may lead to a satisfactory lifestyle.

Kv7 channels a potential therapeutic target in fibromyalgia: A hypothesis

Fibromyalgia is characterized by the primary symptoms of persistent diffuse pain, fatigue, sleep disturbance and cognitive dysfunction. Persistent pain conditions, such as fibromyalgia, are often refractory to current available therapies. An involvement of K⁺ channels in the pathophysiology of fibromyalgia is emerging and supported by drug treatments for this condition exhibiting action at these molecular processes. K⁺ channels constitute potential novel target candidates for pain therapy offering peripheral and/or central actions. The Kv7 channel activators, flupirtine and retigabine, have exhibited pharmacological profiles compatible to the requirements needed for use as a therapeutic approach to fibromyalgia. Clinical trials to address the multidimensional challenges of fibromyalgia with flupirtine and retigabine will provide important insight to the role of K⁺ channels in this condition.

Pharmacological therapies for fibromyalgia in adults ‐ an overview of Cochrane Reviews

This is a protocol for a Cochrane Review (Overview). The objectives are as follows:

To provide an overview of the therapeutic efficacy of pharmacological therapies for fibromyalgia, and to report on adverse events associated with their use. The major comparison of interest will be with placebo.

Multisite musculoskeletal pain trajectories from midlife to old age: a 28-year follow-up of municipal employees

OBJECTIVES

We studied the developmental trajectories of multisite musculoskeletal pain (MSP) to learn whether pain in midlife persists to old age, and whether pain trajectories associate with midlife work or lifestyle exposures or retirement from work.

METHODS

Municipal employees aged 44-58 years were studied in 1981 (n=6257) with follow-ups in 1985, 1992, 1997 and 2009. Pain in the neck, low back, and upper and lower limbs was assessed in each survey. Trajectories of the number (0-4) of pain sites were defined using growth mixture modelling (n=3093). Workload, lifestyle and morbidity were elicited by questionnaire and retirement from registries. Associations of baseline factors with pain trajectories were assessed by multinomial logistic regression. Cumulative hazard curves for retirement by trajectory group were calculated.

RESULTS

Three trajectories of pain over 28 years emerged: low (25%), moderate (52%) and high-decreasing (23%). In the latter, the number of pain sites first decreased sharply, stabilising to a moderate level after most subjects had retired. The disability pension rate was highest in this trajectory, which associated with high baseline morbidity, particularly musculoskeletal disorder (OR 8.06; 95% CI 5.97 to 10.87). Also high biomechanical exposure (2.86;95% CI 2.16 to 3.78), high job demands (1.79; 95% CI 1.39 to 2.30), high job control (OR 0.70; 95% CI 0.54 to 0.90), body mass index (BMI) ≥25.0 kg/m² (1.40; 95% CI 1.09 to 1.80) and low leisure-time physical activity (LTPA) (1.39; 95% CI 1.09 to 1.78) at baseline were associated with this trajectory. However, high LTPA and BMI in repeated surveys also associated with the high-decreasing trajectory.

CONCLUSION

MSP in midlife often persists to old age. However, high widespreadness of pain may decrease with retirement from work.

Effects of Physical-Agent Pain Relief Modalities for Fibromyalgia Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Purpose

We conducted a systematic review and meta-analysis to investigate the effects of the following physical-agent modalities for pain relief in fibromyalgia (FM) patients.

Methods

We identified randomized controlled studies of adults with FM in the MEDLINE, CINAHL, and PEDro databases. The primary outcome measure was pain relief measured by a visual analogue scale (VAS), and the secondary outcome measures of interest were subjective improvements in the number of tender points, Fibromyalgia Impact Questionnaire (FIQ), and quality of life (QOL) scores.

Results

Eleven studies were included in our review. The studies' physical-agent modalities were low-level laser therapy (LLLT), thermal therapy, electromagnetic field therapy, and transcutaneous electrical nerve stimulation (TENS). LLLT did not reduce VAS scores, but it significantly reduced both the number of tender points and FIQ score. Thermal therapy was associated with significantly reduced VAS scores, tender points, and FIQ scores. Electromagnetic field therapy was associated with significantly reduced VAS score and FIQ score. TENS significantly reduced VAS scores.

Conclusion

Our analyses revealed that thermal therapy and LLLT had a partial effect on pain relief in FM patients, and this beneficial effect may have a positive influence on FM patients' health status.

NYX-2925, A Novel N-methyl-D-aspartate Receptor Modulator: A First-in-Human, Randomized, Double-blind Study of Safety and Pharmacokinetics in Adults

NYX‐2925, a new chemical entity, acts as a co‐agonist to glutamate at the N‐methyl‐D‐aspartate receptor (NMDAR). At low concentrations of endogenous agonists (glycine/D‐serine), NYX‐2925 partially activates NMDARs, modulating neural pathways relevant for chronic pain. NYX‐2925 is being developed for the treatment of chronic pain conditions, including painful diabetic peripheral neuropathy and fibromyalgia. In this first‐in‐human, phase I, single‐ascending dose (50–1,200 mg) and multiple‐ascending dose (150–900 mg) study, the safety, tolerability, and pharmacokinetics (PKs) of NYX‐2925 were evaluated in 84 healthy adult volunteers. No safety concerns emerged, including no dissociative side effects. NYX‐2925 exhibited dose‐proportional PKs and minimal accumulation following once‐daily dosing for 7 days. Cerebrospinal fluid (CSF) measurements confirmed that NYX‐2925 crosses the blood brain barrier, with maximum CSF concentrations approximating 6–9% of maximum plasma concentrations at the same dose level. NYX‐2925 was safe and well‐tolerated in healthy volunteers, and the study results support the continued clinical development for chronic pain conditions.

Experiences from group basic body awareness therapy by patients suffering from fibromyalgia: A qualitative study

The aim of this study was to obtain a deeper understanding of how patients with fibromyalgia experienced movement awareness through a basic body awareness therapy group treatment program. A total of 19 participants with fibromyalgia diagnosis were interviewed individually and in groups. Data collection was done from three sources: (1) interviews from the Basic Body Awareness Rating Scale (BARS) part 2 at baseline, at end of treatment, as well as at 12 and 24 weeks follow up; (2) focus group discussions that took place at the end of each session, and at the end of treatment; and (3) an in-depth focus group. Giorgi's method was followed for data construction and analysis. The researchers conducted 57 individual interviews, 10 focus groups, and one in-depth focus group. The findings revealed the following categories: "creating a new relation to self"; "change the pattern of body awareness"; "being in a group"; and "experiencing physical capacity", showing influences among them. Body awareness seems to have an impact in the therapeutic process in patients suffering from fibromyalgia.

Fibromyalgia: is it a neuropathic pain?

Fibromyalgia is a chronic pain syndrome of unclear pathophysiology. It is believed to be a dysfunction of the CNS, but no definite structural lesion has been identified so far. Despite a number of changes in the diagnostic criteria, diagnosis remains a clinical one. Since the 2011 revision of the IASP definition of neuropathic pain, fibromyalgia has been excluded from the diagnosis of neuropathic pain. More recent studies however found newer evidences of pathophysiology including small fiber neuropathy in patients with fibromyalgia. This may challenge the existing consensus and have implications on future diagnosis and management of this condition.

Effect of providing drug utilization review information on tricyclic antidepressant prescription in the elderly

Tricyclic antidepressants are known as potentially inappropriate medications in the elderly. A notification issued in July 2015 in South Korea recommended caution while prescribing tricyclic antidepressants to the elderly. Further, since October 2015, the nationwide computerized drug utilization review monitoring system provides a pop-up window, on a real-time basis, whenever tricyclic antidepressants are prescribed to elderly outpatients. Therefore, we evaluated whether providing drug utilization review information was effective in reducing tricyclic antidepressant prescription to elderly outpatients. We used the Health Insurance Review and Assessment Service-Adult Patient Sample data from 2014 to 2016. Data related to the prescription of tricyclic antidepressants to outpatients aged 65 years or more were extracted. We determined the number of prescriptions per day per 100,000 elderly patients in each month, compared the average number of prescriptions before and after the drug utilization review information was provided, and evaluated the changes in the number of prescriptions by using an interrupted time series analysis. The average number of tricyclic antidepressant prescriptions per day per 100,000 elderly patients decreased from 76.6 (75.5 to 77.6) to 65.7 (64.5 to 66.9), a 14.2% reduction after the provision of drug utilization review information started. Following initiation of provision of drug utilization review information, there was an immediate drop of 9.2 tricyclic antidepressant prescriptions per day per 100,000 elderly patients, whereas there was no statistically significant change in trends. Providing the drug utilization review information on tricyclic antidepressant prescription for the elderly contributed to the reduction in tricyclic antidepressant prescriptions.

Prescribed Versus Preferred Intensity Resistance Exercise in Fibromyalgia Pain

Exercise is the treatment of choice for fibromyalgia (FM), but little is known about resistance exercise prescription to modulate pain in this condition. This study aimed to compare the effects of different resistance exercise models, comprising self-selected or prescribed intensity, on pain in FM patients. In a cross-over fashion, 32 patients underwent the following sessions: (i) standard prescription (STD; 3 × 10 repetitions at 60% of maximal strength); (ii) self-selected load with fixed number of repetitions (SS); (iii) self-selected load with volume load (i.e., load × sets × repetitions) matched for STD (SS-VM); and (iv) self-selected load with a free number of repetitions until achieving score 7 of rating perceived exertion (SS-RPE). Pain, assessed by Visual Analogic Scale (VAS) and Short-Form McGill Pain Questionnaire (SF-MPQ), was evaluated before and 0, 24, 48, 72, and 96 h after the sessions. Load was significantly lower in SS, SS-VM, SS-RPE than in STD, whereas rating perceived exertion and volume load were comparable between sessions. VAS scores increased immediately after all sessions (p < 0.0001), and reduced after 48, 72, 96 h (p < 0.0001), remaining elevated compared to pre-values. SF-MPQ scores increased immediately after all exercise sessions (p = 0.025), then gradually reduced across time, reaching baseline levels at 24 h. No significant differences between sessions were observed. Both prescribed and preferred intensity resistance exercises failed in reducing pain in FM patients. The recommendation that FM patients should exercise at preferred intensities to avoid exacerbated pain, which appears to be valid for aerobic exercise, does not apply to resistance exercise.

Mirtazapine for fibromyalgia in adults

BACKGROUND

Fibromyalgia is a clinically defined chronic condition of unknown etiology characterised by chronic widespread pain, sleep disturbance, cognitive dysfunction, and fatigue. Many patients report high disability levels and poor quality of life. Drug therapy aims to reduce key symptoms, especially pain, and improve quality of life. The tetracyclic antidepressant, mirtazapine, may help by increasing serotonin and noradrenaline in the central nervous system (CNS).

OBJECTIVES

To assess the efficacy, tolerability and safety of the tetracyclic antidepressant, mirtazapine, compared with placebo or other active drug(s) in the treatment of fibromyalgia in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, SCOPUS, the US National Institutes of Health, and the World Health Organization (WHO) International Clinical Trials Registry Platform for published and ongoing trials, and examined reference lists of reviewed articles, to 9 July 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any formulation of mirtazapine against placebo, or any other active treatment of fibromyalgia, in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted study characteristics, outcomes of efficacy, tolerability and safety, examined issues of study quality, and assessed risk of bias, resolving discrepancies by discussion. Primary outcomes were participant-reported pain relief (at least 50% or 30% pain reduction), Patient Global Impression of Change (PGIC; much or very much improved), safety (serious adverse events), and tolerability (adverse event withdrawal). Other outcomes were health-related quality of life (HRQoL) improved by 20% or more, fatigue, sleep problems, mean pain intensity, negative mood and particular adverse events. We used a random-effects model to calculate risk difference (RD), standardised mean difference (SMD), and numbers needed to treat. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

Three studies with 606 participants compared mirtazapine with placebo (but not other drugs) over seven to 13 weeks. Two studies were at unclear or high risk of bias in six or seven of eight domains. We judged the evidence for all outcomes to be low- or very low-quality because of poor study quality, indirectness, imprecision, risk of publication bias, and sometimes low numbers of events.There was no difference between mirtazapine and placebo for any primary outcome: participant-reported pain relief of 50% or greater (22% versus 16%; RD 0.05, 95% confidence interval (CI) -0.01 to 0.12; three studies with 591 participants; low-quality evidence); no data available for PGIC; only a single serious adverse event for evaluation of safety (RD -0.00, 95% CI -0.01 to 0.02; three studies with 606 participants; very low-quality evidence); and tolerability as frequency of dropouts due to adverse events (3% versus 2%; RD 0.00, 95% CI -0.02 to 0.03; three studies with 606 participants; low-quality evidence).Mirtazapine showed a clinically-relevant benefit compared to placebo for some secondary outcomes: participant-reported pain relief of 30% or greater (47% versus 34%; RD 0.13, 95% CI 0.05 to 0.21; number needed to treat for an additional beneficial outcome (NNTB) 8, 95% CI 5 to 20; three studies with 591 participants; low-quality evidence); participant-reported mean pain intensity (SMD -0.29, 95% CI -0.46 to -0.13; three studies with 591 participants; low-quality evidence); and participant-reported sleep problems (SMD -0.23, 95% CI -0.39 to -0.06; three studies with 573 participants; low-quality evidence). There was no benefit for improvement of participant-reported improvement of HRQoL of 20% or greater (58% versus 50%; RD 0.08, 95% CI -0.01 to 0.16; three studies with 586 participants; low-quality evidence); participant-reported fatigue (SMD -0.02, 95% CI -0.19 to 0.16; two studies with 533 participants; low-quality evidence); participant-reported negative mood (SMD -0.67, 95% CI -1.44 to 0.10; three studies with 588 participants; low-quality evidence); or withdrawals due to lack of efficacy (1.5% versus 0.1%; RD 0.01, 95% CI -0.01 to 0.02; three studies with 605 participants; very low-quality evidence).There was no difference between mirtazapine and placebo for participants reporting any adverse event (76% versus 59%; RD 0.12, 95 CI -0.01 to 0.26; three studies with 606 participants; low-quality evidence). There was a clinically-relevant harm with mirtazapine compared to placebo: in the number of participants with somnolence (42% versus 14%; RD 0.24, 95% CI 0.18 to 0.30; number needed to treat for an additional harmful outcome (NNTH) 5, 95% CI 3 to 6; three studies with 606 participants; low-quality evidence); weight gain (19% versus 1%; RD 0.17, 95% CI 0.11 to 0.23; NNTH 6, 95% CI 5 to 10; three studies with 606 participants; low-quality evidence); and elevated alanine aminotransferase (13% versus 2%; RD 0.13, 95% CI 0.04 to 0.22; NNTH 8, 95% CI 5 to 25; two studies with 566 participants; low-quality evidence).

AUTHORS' CONCLUSIONS

Studies demonstrated no benefit of mirtazapine over placebo for pain relief of 50% or greater, PGIC, improvement of HRQoL of 20% or greater, or reduction of fatigue or negative mood. Clinically-relevant benefits were shown for pain relief of 30% or greater, reduction of mean pain intensity, and sleep problems. Somnolence, weight gain, and elevated alanine aminotransferase were more frequent with mirtazapine than placebo. The quality of evidence was low or very low, with two of three studies of questionable quality and issues over indirectness and risk of publication bias. On balance, any potential benefits of mirtazapine in fibromyalgia were outweighed by its potential harms, though, a small minority of people with fibromyalgia might experience substantial symptom relief without clinically-relevant adverse events.

An evidence-based review of pregabalin for the treatment of fibromyalgia

OBJECTIVES

Pregabalin, an α2-δ agonist, is approved for the treatment of fibromyalgia (FM) in the United States, Japan, and 37 other countries. The purpose of this article was to provide an in-depth, evidence-based summary of pregabalin for FM as demonstrated in randomized, placebo-controlled clinical studies, including open-label extensions, meta-analyses, combination studies and post-hoc analyses of clinical study data.

METHODS

PubMed was searched using the term "pregabalin AND fibromyalgia" and the Cochrane Library with the term "pregabalin". Both searches were conducted on 2 March 2017 with no other date limits set.

RESULTS

Eleven randomized, double-blind, placebo-controlled clinical studies were identified including parallel group, two-way crossover and randomized withdrawal designs. One was a neuroimaging study. Five open-label extensions were also identified. Evidence of efficacy was demonstrated across the studies identified with significant and clinically relevant improvements in pain, sleep quality and patient status. The safety and tolerability profile of pregabalin is consistent across all the studies identified, including in adolescents, with dizziness and somnolence the most common adverse events reported. These efficacy and safety data are supported by meta-analyses (13 studies). Pregabalin in combination with other pharmacotherapies (7 studies) is also efficacious. Post-hoc analyses have demonstrated the onset of pregabalin efficacy as early as 1-2 days after starting treatment, examined the effect of pregabalin on other aspects of sleep beyond quality, and shown it is effective irrespective of the presence of a wide variety of patient demographic and clinical characteristics.

CONCLUSIONS

Pregabalin is a treatment option for FM; its clinical utility has been comprehensively demonstrated.

Pediatric Pain Syndromes and Noninflammatory Musculoskeletal Pain

Chronic musculoskeletal pain (CMP) is one of the main reasons for referral to a pediatric rheumatologist and is the third most common cause of chronic pain in children and adolescents. Causes of CMP include amplified musculoskeletal pain, benign limb pain of childhood, hypermobility, overuse syndromes, and back pain. CMP can negatively affect physical, social, academic, and psychological function so it is essential that clinicians know how to diagnose and treat these conditions. This article provides an overview of the epidemiology and impact of CMP, the steps in a comprehensive pain assessment, and the management of the most common CMPs.

Catecholamine and Indolamine Pathway: A Case-Control Study in Fibromyalgia

OBJECTIVES

Fibromyalgia (FM) is a complex syndrome characterized by widespread pain. Its etiology is unclear, and diagnosis is difficult. The aim of this study was to assess plasma levels of monoamine neurotransmitters (catecholamines, indolamines, and intermediate metabolites) in patients with FM and healthy controls to investigate possible alterations in the metabolism of these molecules in FM. We also examined potential relationships between monoamine neurotransmitters and clinical features of FM. The predictive value of these molecules in FM was determined by receiver operating characteristic analysis.

METHOD

We measured plasma catecholamines (epinephrine, norepinephrine, and dopamine), as well as indolamines and intermediary metabolites (serotonin or 5-hydroxytryptamine [5-HT], 5-hydroxyindolacetic acid [5-HIAA], 5-hydroxytryptophan [5-HTP], and N-acetyl-5-hydroxytryptamine [Nac-5-HT]) in 35 women with FM and 12 age-matched healthy women.

RESULTS

Higher levels of norepinephrine and lower levels of dopamine, 5-HT, 5-HIAA, and 5-HTP were found in women with FM in comparison with controls. Epinephrine and Nac-5-HT levels did not differ significantly between groups. Higher norepinephrine levels were associated with worse physical health status in FM patients. Also, plasma norepinephrine levels > 694.69 pg/ml might be an accurate predictor of FM.

CONCLUSIONS

These findings show evidence of the dysregulation of the catecholamine and indolamine pathway in patients with FM, which may contribute to the physiopathology of this syndrome. In addition, the determination of plasma norepinephrine levels could help in the FM diagnosis.

Effects of a community-based multicomponent rehabilitation programme for patients with fibromyalgia: protocol for a randomised controlled trial

INTRODUCTION

People with fibromyalgia (FM) suffer from symptoms such as widespread pain, non-refreshing sleep, fatigue and reduced quality of life. Effects of pharmacological treatment are questionable and non-pharmacological treatments are recommended as first-line therapy. To date the majority of patients with FM in Norway are not offered any targeted treatment. The aim of this randomised controlled trial is to investigate the effects of a community-based multicomponent rehabilitation programme comprising an acceptance-based and mindfulness-based group intervention, the Vitality Training Programme (VTP), followed by tailored physical activity counselling.

MATERIALS AND METHODS

General practitioners refer potential participants to a rheumatologist in specialist healthcare for diagnostic clarification and assessment of comorbidities. Inclusion criteria are widespread pain/FM ≥3 months, age 20-50 and work participation (minimum part-time) within the last 2 years. The intervention group attends the VTP comprising 10 weekly 4 hour group sessions plus a booster session after 6 months. Thereafter, they receive 12 weeks of individually tailored physical exercise counselled by physiotherapists at community-based Healthy Life Centers. The control group follows treatment as usual. The primary outcome is Patient Global Impression of Change. Secondary outcomes include self-reported pain, fatigue and sleep quality, psychological distress, mindfulness, health-related quality of life, physical activity, work ability and exercise beliefs and habits. To achieve a power of 80% and allow for 10% dropout, 70 participants are needed in each arm. All analyses will be conducted on intention-to-treat bases and measured as differences between groups at 12 months follow-up.

ETHICS AND DISSEMINATION

The study is approved and granted by the Norwegian South-Eastern Regional Health Authority (reference 2016015). Ethics approval was obtained from Regional Committee for Medical and Health Research Ethics (reference 2015/2447/REK sør-øst A). Results will be submitted to appropriate journals and presented in relevant conferences and social media.

TRIAL REGISTRATION

ISRCTN 96836577.

The role of mirtazapine in patients with fibromyalgia: a systematic review

Mirtazapine is commonly used to treat major depressive disorder. Due to its effects on multiple neurotransmitters, it has been investigated for possible benefits in patients with fibromyalgia. The objective of this systematic review is to assess the efficacy and safety of mirtazapine in the treatment of patients with fibromyalgia. Pubmed (1946-May 2018), Embase (1947-May 2018), CENTRAL, and ClinicalTrials.gov were queried using the search term combination: fibromyalgia, pain, chronic pain, neuralgia, neuropathic pain, chronic widespread pain, or chronic pain syndrome and mirtazapine. Studies appropriate to the objective were evaluated, including three randomized, placebo-controlled trials and one open-label trial, investigating the effect of mirtazapine in patients with fibromyalgia. In patients with fibromyalgia, treatment with mirtazapine resulted in improvements in pain, sleep, and quality of life. Study durations ranged from 6 to 13 weeks and studies used varying dosing strategies for mirtazapine. Minor occurrences of somnolence, weight gain, nasopharyngitis, dry mouth, and increased appetite were reported with mirtazapine use. Based on the reviewed literature, mirtazapine appears to be a promising therapy to improve pain, sleep, and quality of life in patients with fibromyalgia. These benefits were demonstrated in patients that were treatment naïve and those that had failed previous therapies. Additional clinical evidence through larger and longer length trials would be of benefit to further define the role of mirtazapine for patients with fibromyalgia.

Fibromyalgia Syndrome: A Case Report on Controlled Remission of Symptoms by a Dietary Strategy

A 34-year-old woman suffered from significant chronic pain, depression, non-restorative sleep, chronic fatigue, severe morning stiffness, leg cramps, irritable bowel syndrome, hypersensitivity to cold, concentration difficulties, and forgetfulness. Blood tests were negative for rheumatic disorders. The patient was diagnosed with Fibromyalgia syndrome (FMS). Due to the lack of effectiveness of pharmacological therapies in FMS, she approached a novel metabolic proposal for the symptomatic remission. Its core idea is supporting serotonin synthesis by allowing a proper absorption of tryptophan assumed with food, while avoiding, or at least minimizing the presence of interfering non-absorbed molecules, such as fructose and sorbitol. Such a strategy resulted in a rapid improvement of symptoms after only few days on diet, up to the remission of most symptoms in 2 months. Depression, widespread chronic pain, chronic fatigue, non-restorative sleep, morning stiffness, and the majority of the comorbidities remitted. Energy and vitality were recovered by the patient as prior to the onset of the disease, reverting the occupational and social disabilities. The patient episodically challenged herself breaking the dietary protocol leading to its negative test and to the evaluation of its benefit. These breaks correlated with the recurrence of the symptoms, supporting the correctness of the biochemical hypothesis underlying the diet design toward remission of symptoms, but not as a final cure. We propose this as a low risk and accessible therapeutic protocol for the symptomatic remission in FMS with virtually no costs other than those related to vitamin and mineral salt supplements in case of deficiencies. A pilot study is required to further ground this metabolic approach, and to finally evaluate its inclusion in the guidelines for clinical management of FMS.

Scoping Review of Dance for Adults With Fibromyalgia: What Do We Know About It?

BACKGROUND

Fibromyalgia is a chronic disorder characterized by widespread muscular tenderness, pain, fatigue, and cognitive difficulties. Nonpharmacological treatment options, such as physical activity, are important for people with fibromyalgia. There are strong recommendations to support engagement in physical activity for symptom management among adults with fibromyalgia. Dance is a mode of physical activity that may allow individuals with fibromyalgia to improve their physical function, health, and well-being. Dance has the potential to promote improved pain processing while simultaneously providing the health and social benefits of engaging in physical activity that contributes to symptom management and overall function rehabilitation. However, we are unaware of current evidence on dance as a nonpharmacological/physical activity intervention for adults with fibromyalgia.

OBJECTIVE

The aims of this study were to understand how dance is used therapeutically by individuals with fibromyalgia; to examine the extent, range and nature of research activity in the area; and to determine the value of undertaking a systematic review of interventions.

METHODS

We used and adapted the Arksey and O'Malley scoping framework. The search strategy involved a comprehensive search of main health and electronic social databases, trial registries and grey literature without language limits. Pairs of reviewers independently screened and extracted data and evaluated the methodological quality of randomized control trials.

RESULTS

Twenty-one unique records for 13 studies met inclusion criteria; the studies included mostly middle-aged women. Types of dance included were aerobic dance, belly dance, dance movement therapy, biodanza and Zumba. Intervention parameters were different among studies. Frequency varied between one to three times a week; all were done in small group settings. Studies evaluated a variety of outcomes in the symptoms, wellness, psychosocial, physical functioning, balance and fitness categories; no studies evaluated the safety or adverse events systematically which is a major weakness of the literature.

CONCLUSIONS

There are few studies in the field of dance and fibromyalgia, suggesting research is in its infancy but slowly growing. They are of European and South American origin, focusing on female participants and a limited number of dance modes. Because the body of literature is small, of low quality and highly heterogeneous, we concluded that a systematic review of interventions on dance is not warranted at this time.

Pulsed electromagnetic field therapy in the treatment of pain and other symptoms in fibromyalgia: A randomized controlled study

Low-energy pulsed electromagnetic field (PEMF) therapy has been suggested as a promising therapy to increase microcirculation, which is of great concern in patients with fibromyalgia. This study evaluated the effectiveness of PEMF therapy on the treatment of fibromyalgia. A group of 108 women with fibromyalgia were allocated to a 12-week treatment period with an active Bio-Electro-Magnetic-Energy-Regulation (BEMER) device and a similar treatment period with an inactive device. Each patient received active and sham treatments in a random order. Pain and stiffness were assessed on a visual analog scale (VAS, scale 0-100 mm), and functional status was assessed by the Fibromyalgia Impact Questionnaire (FIQ). Mean VAS pain scores before the active and sham treatment periods were 66 (SD 22) and 63 (SD 22), respectively. After treatment periods, mean VAS pain scores had decreased significantly in active treatment, -12, 95% CI [-18, -6], and in sham treatment, -11, 95% CI [-17, -5]. Similarly, the decrease in stiffness and FIQ index after both treatments was statistically significant. However, per-protocol analysis showed no differences between active and sham treatments at any of the outcomes. This study demonstrated that low-energy PEMF therapy was not efficient in reducing pain and stiffness or in improving functioning in women with fibromyalgia. Bioelectromagnetics. 39:405-413, 2018. © 2018 Wiley Periodicals, Inc.

Effects of pregabalin and duloxetine on neurotransmitters in the dorsal horn of the spinal cord in a rat model of fibromyalgia

Dysfunction of the monoamine systems in the nervous system is associated with the clinical symptoms of fibromyalgia. Reserpine-induced myalgia (RIM) rats are a putative model of fibromyalgia in which muscle pressure thresholds and monoamine content is reduced in the brain and spinal cord. We examined the effects of pregabalin and duloxetine, drugs approved for fibromyalgia treatment, on the levels of extracellular neurotransmitters in the dorsal horn of the spinal cord in RIM rats using microdialysis. Male SD rats were used for all experiments. To generate RIM rats, reserpine was injected at 1 mg/kg subcutaneously once daily for three consecutive days. The pressure threshold of the mid-gastrocnemius muscle was measured using a Randall-Selitto apparatus. Norepinephrine, dopamine, and serotonin were detected using high-performance liquid chromatography with electrochemical detection, and glutamate and γ-aminobutyric acid (GABA) were detected using liquid chromatography-mass spectrometry. The muscle pressure threshold in RIM rats was significantly lower than that in normal rats. While the levels of monoamines and glutamate were lower in the spinal cord of RIM rats than in normal rats, levels of GABA did not markedly differ. Duloxetine increased the levels of all three monoamines in normal and RIM rats in a dose-dependent manner. In contrast, pregabalin only increased norepinephrine levels in RIM rats. These results indicate that while both pregabalin and duloxetine ameliorate muscle pressure thresholds in RIM rats, their effects on the levels of extracellular neurotransmitters in the spinal cord differ considerably.

Serotonin and noradrenaline reuptake inhibitors (SNRIs) for fibromyalgia

BACKGROUND

Fibromyalgia is a clinically defined chronic condition of unknown etiology characterized by chronic widespread pain that often co-exists with sleep disturbances, cognitive dysfunction and fatigue. People with fibromyalgia often report high disability levels and poor quality of life. Drug therapy, for example, with serotonin and noradrenaline reuptake inhibitors (SNRIs), focuses on reducing key symptoms and improving quality of life. This review updates and extends the 2013 version of this systematic review.

OBJECTIVES

To assess the efficacy, tolerability and safety of serotonin and noradrenaline reuptake inhibitors (SNRIs) compared with placebo or other active drug(s) in the treatment of fibromyalgia in adults.

SEARCH METHODS

For this update we searched CENTRAL, MEDLINE, Embase, the US National Institutes of Health and the World Health Organization (WHO) International Clinical Trials Registry Platform for published and ongoing trials and examined the reference lists of reviewed articles, to 8 August 2017.

SELECTION CRITERIA

We selected randomized, controlled trials of any formulation of SNRIs against placebo or any other active treatment of fibromyalgia in adults.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data, examined study quality, and assessed risk of bias. For efficacy, we calculated the number needed to treat for an additional beneficial outcome (NNTB) for pain relief of 50% or greater and of 30% or greater, patient's global impression to be much or very much improved, dropout rates due to lack of efficacy, and the standardized mean differences (SMD) for fatigue, sleep problems, health-related quality of life, mean pain intensity, depression, anxiety, disability, sexual function, cognitive disturbances and tenderness. For tolerability we calculated number needed to treat for an additional harmful outcome (NNTH) for withdrawals due to adverse events and for nausea, insomnia and somnolence as specific adverse events. For safety we calculated NNTH for serious adverse events. We undertook meta-analysis using a random-effects model. We assessed the evidence using GRADE and created a 'Summary of findings' table.

MAIN RESULTS

We added eight new studies with 1979 participants for a total of 18 included studies with 7903 participants. Seven studies investigated duloxetine and nine studies investigated milnacipran against placebo. One study compared desvenlafaxine with placebo and pregabalin. One study compared duloxetine with L-carnitine. The majority of studies were at unclear or high risk of bias in three to five domains.The quality of evidence of all comparisons of desvenlafaxine, duloxetine and milnacipran versus placebo in studies with a parallel design was low due to concerns about publication bias and indirectness, and very low for serious adverse events due to concerns about publication bias, imprecision and indirectness. The quality of evidence of all comparisons of duloxetine and desvenlafaxine with other active drugs was very low due to concerns about publication bias, imprecision and indirectness.Duloxetine and milnacipran had no clinically relevant benefit over placebo for pain relief of 50% or greater: 1274 of 4104 (31%) on duloxetine and milnacipran reported pain relief of 50% or greater compared to 591 of 2814 (21%) participants on placebo (risk difference (RD) 0.09, 95% confidence interval (CI) 0.07 to 0.11; NNTB 11, 95% CI 9 to 14). Duloxetine and milnacipran had a clinically relevant benefit over placebo in patient's global impression to be much or very much improved: 888 of 1710 (52%) on duloxetine and milnacipran (RD 0.19, 95% CI 0.12 to 0.26; NNTB 5, 95% CI 4 to 8) reported to be much or very much improved compared to 354 of 1208 (29%) of participants on placebo. Duloxetine and milnacipran had a clinically relevant benefit compared to placebo for pain relief of 30% or greater. RD was 0.10; 95% CI 0.08 to 0.12; NNTB 10, 95% CI 8 to 12. Duloxetine and milnacipran had no clinically relevant benefit for fatigue (SMD -0.13, 95% CI -0.18 to -0.08; NNTB 18, 95% CI 12 to 29), compared to placebo. There were no differences between either duloxetine or milnacipran and placebo in reducing sleep problems (SMD -0.07; 95 % CI -0.15 to 0.01). Duloxetine and milnacipran had no clinically relevant benefit compared to placebo in improving health-related quality of life (SMD -0.20, 95% CI -0.25 to -0.15; NNTB 11, 95% CI 8 to 14).There were 794 of 4166 (19%) participants on SNRIs who dropped out due to adverse events compared to 292 of 2863 (10%) of participants on placebo (RD 0.07, 95% CI 0.04 to 0.10; NNTH 14, 95% CI 10 to 25). There was no difference in serious adverse events between either duloxetine, milnacipran or desvenlafaxine and placebo (RD -0.00, 95% CI -0.01 to 0.00).There was no difference between desvenlafaxine and placebo in efficacy, tolerability and safety in one small trial.There was no difference between duloxetine and desvenlafaxine in efficacy, tolerability and safety in two trials with active comparators (L-carnitine, pregabalin).

AUTHORS' CONCLUSIONS

The update did not change the major findings of the previous review. Based on low- to very low-quality evidence, the SNRIs duloxetine and milnacipran provided no clinically relevant benefit over placebo in the frequency of pain relief of 50% or greater, but for patient's global impression to be much or very much improved and in the frequency of pain relief of 30% or greater there was a clinically relevant benefit. The SNRIs duloxetine and milnacipran provided no clinically relevant benefit over placebo in improving health-related quality of life and in reducing fatigue. Duloxetine and milnacipran did not significantly differ from placebo in reducing sleep problems. The dropout rates due to adverse events were higher for duloxetine and milnacipran than for placebo. On average, the potential benefits of duloxetine and milnacipran in fibromyalgia were outweighed by their potential harms. However, a minority of people with fibromyalgia might experience substantial symptom relief without clinically relevant adverse events with duloxetine or milnacipran.We did not find placebo-controlled studies with other SNRIs than desvenlafaxine, duloxetine and milnacipran.

Longitudinal stability of fibromyalgia symptom clusters

Background

Using self-report questionnaires of key fibromyalgia symptom domains (pain, fatigue, sleep disturbance, function, stiffness, dyscognition, depression, and anxiety), we previously identified four unique symptom clusters. The purpose of this study was to examine the stability of fibromyalgia symptom clusters between baseline and 2-year follow-up.

Methods

Women with a diagnosis of fibromyalgia completed the Brief Pain Inventory, Profile of Mood States, Medical Outcomes Study Sleep measure, Multidimensional Fatigue Inventory, Multiple Ability Self-Report Questionnaire, Revised Fibromyalgia Impact Questionnaire, and the 36-Item Short Form Survey Instrument at baseline. Follow-up measures were completed approximately 2 years later. The hierarchical agglomerative clustering algorithm previously developed was applied; agreement between baseline and follow-up was assessed with the κ statistic.

Results

Among 433 participants, the mean age was 56 (range 20–85) years. The median Revised Fibromyalgia Impact Questionnaire total score was 57 (range 8–96). More than half of participants (58%) remained in the same cluster at follow-up as at baseline, which represented moderate agreement between baseline and follow-up (κ = 0.44, 95% confidence interval (CI) 0.37–0.50). Only two patients changed from high symptom intensity to low symptom intensity; similarly, only three moved from low to high.

Conclusions

Fibromyalgia patients classified into four unique symptom clusters based on the key domains of pain, fatigue, sleep disturbance, function, stiffness, dyscognition, depression, and anxiety showed moderate stability in cluster assignment after 2 years. Few patients moved between the two extremes of severity, and it was slightly more common to move to a lower symptom level than to worsen.

Trial registration

Not applicable.

Efficacy, acceptability and safety of cognitive behavioural therapies in fibromyalgia syndrome - A systematic review and meta-analysis of randomized controlled trials

This updated systematic review aimed at evaluating the efficacy, acceptability and safety of cognitive behavioural therapies (CBTs) in fibromyalgia syndrome (FMS). Clinicaltrials.gov, Cochrane Library, MEDLINE, PsycINFO and SCOPUS were searched from September 2013 to May 2017. Randomized controlled trials (RCTs) comparing CBTs with controls were analysed. Primary outcomes were ≥50% pain relief, ≥20% improvement of health-related quality of life (HRQoL), negative mood, fatigue, disability, acceptability and safety at end of therapy and at 6 months follow-up. Effects were summarized by a random effects model using risk differences (RD) or standardized mean differences (SMD) with 95% confidence intervals (CI). 29 RCTs with 2509 subjects were included. CBTs were superior to controls (waiting list, attention control, treatment as usual, other active non-pharmacological therapies) in pain relief of 50% or greater (RD 0.05 [95% CI 0.02-0.07] (high-quality evidence), improvement of HRQoL of 20% or greater (RD 0.13 [95% CI 0.00-0.26], (moderate quality evidence), and in reducing negative mood (SMD -0.43 [95% CI -0.62 to -0.24]) (high-quality evidence), disability (SMD -0.30 [95% CI -0.52 to -0.08]) (high-quality evidence) and fatigue (SMD - 0-27 [95% CI -0.50 to -0.03]) (high-quality evidence). There were no statistically significant differences between CBTs and controls in acceptability and safety (high-quality evidence). The update did not change the major findings of the previous review. CBTs provided a clinically relevant benefit over control interventions in reducing some key symptoms of FMS and disability at the end of treatment.

SIGNIFICANCE

This updated systematic review with meta-analysis on cognitive behavioural therapies (CBTs) including acceptance-based CBTs endorse the efficacy and tolerability of CBTs in reducing key symptoms and disability in FMS in the short- and long-term if compared to waiting list, treatment as usual, attention controls and active non-pharmacological therapies. CBTs did not differ in efficacy except superiority for coping with pain and tolerability from recommended drug therapy (pregabalin and/or duloxetine).

Proportion of contextual effects in the treatment of fibromyalgia-a meta-analysis of randomised controlled trials

The objective of this study is to examine the proportion of the total treatment effect that is attributable to contextual effects in randomised controlled trials (RCTs) of treatments for fibromyalgia. A systematic literature search was undertaken in Medline, Web of Science, EMBASE, Cumulative Index to Nursing and Allied Health Literature (CINAHL), and Allied and Complementary Medicine in September 2015. The proportion of contextual effect (PCE) was calculated by dividing the improvement in the placebo arm by the improvement in the treatment arm. The measure was log-transformed for each trial and the random effects model was used to pool data. The primary outcome was pain. Secondary outcomes were fibromyalgia impact questionnaire (FIQ) total and fatigue. Heterogeneity was quantified using I ². Publication bias was assessed using a funnel plot and Egger's test. Subgroup analysis was undertaken to explore heterogeneity and potential determinants of the PCE. Fifty-one eligible trials (9599 participants) were identified. The PCE was 0.60 (95% CI 0·56 to 0·64) for pain, 0·57 (95% CI 0·53 to 0·61) for FIQ total, and 0·63 (95% CI 0·59 to 0·68) for fatigue. The I ² was 99.4% for pain, 99.2% for FIQ total, and 97.6% for fatigue. More than half of the treatment effect in fibromyalgia RCTs results from non-specific contextual factors. This suggests that optimising contextual care may enhance treatment effects and improve outcomes. Reporting the total treatment effect and the proportion of contextual effect in trials may help to better translate research evidence into practice.

Normalizing fibromyalgia as a chronic illness

Fibromyalgia (FM) is a complex chronic disease that affects 3-10% of the general adult population and is principally characterized by widespread pain, and is often associated with disrupted sleep, fatigue, and comorbidities, among other symptoms. There are many gaps in our knowledge of FM, such that, compared with other chronic illnesses including diabetes, rheumatoid arthritis, and asthma, it is far behind in terms of provider understanding and therapeutic approaches. The experience that healthcare professionals (HCPs) historically gained in developing approaches to manage and treat patients with these chronic illnesses may help show how they can address similar problems in patients with FM. In this review, we examine some of the issues around the management and treatment of FM, and discuss how HCPs can implement appropriate strategies for the benefit of patients with FM. These issues include understanding that FM is a legitimate condition, the benefits of prompt diagnosis, use of non-drug and pharmacotherapies, patient and HCP education, watchful waiting, and assessing patients by FM domain so as not to focus exclusively on one symptom to the detriment of others. Developing successful approaches is of particular importance for HCPs in the primary care setting who are in the ideal position to provide long-term care for patients with FM. In this way, FM may be normalized as a chronic illness to the benefit of both patients and HCPs.

Fibromyalgia Syndrome: A Metabolic Approach Grounded in Biochemistry for the Remission of Symptoms

Fibromyalgia syndrome (FMS) is a chronic, complex, and heterogeneous disorder of still poorly understood etiopathophysiology associated with important musculoskeletal widespread pain, fatigue, non-restorative sleep, and mood disturbances. It is estimated to afflict 2–3% of the worldwide population, with clean prevalence among women. The objective of this paper is to propose a novel treatment for symptomatic remission of FMS, grounded in biochemistry and consisting in the withdrawal from the diet of molecules that can indirectly trigger the symptoms. The hypothesis develops from the evidence that low serotonin levels are involved in FMS. Serotonin is synthesized starting from the essential amino acid tryptophan. The presence of non-absorbed molecules in the gut, primarily fructose, reduces tryptophan absorption. Low tryptophan absorption leads to low serotonin synthesis that triggers FMS symptoms. Moreover not-absorbed sugars could also produce a microbiota deterioration activating a positive feedback loop: the increasing microbiota deterioration reduces the functionality of absorption both of fructose and tryptophan in the gut, entering a vicious circle. The therapeutic idea is to sustain serotonin synthesis allowing the proper tryptophan absorption. The core of the cure treatment is the exclusion from the diet of some carbohydrates and the marked reduction of some others. The main target is the limitation of total dietary fructose as marked as possible. It could be an effective strategy to get the remission of symptoms acting on the impaired biochemical pathways. The straying from the treatment is expected to cause the reappear of the symptoms.