Low-Level Laser Therapy for Fibromyalgia: A Systematic Review and Meta-Analysis

Abstract

Background: Fibromyalgia is a chronic disorder characterized by widespread pain and tenderness. Low-level laser therapy (LLLT), an emerging nonpharmacological treatment, has been used for relieving musculoskeletal or neuropathic pain. Objective: The objective of this review and meta-analysis was to determine the efficacy of LLLT on patients with fibromyalgia. Study Design: This study involved systematic review and quantitative meta-analysis of published randomized controlled trials (RCTs). Setting: This study examined all RCTs evaluating the effect of LLLT on fibromyalgia. Methods: We performed a systematic review and meta-analysis of RCTs evaluating the effect of LLLT on patients with fibromyalgia. PubMed, EMBASE, and the Cochrane Library were searched for articles published before August 2018. RCTs meeting our selection criteria were included. The methodological quality of the RCTs was evaluated according to the Cochrane risk-for-bias method. Review Manager version 5.3 was used to perform the meta-analysis. The primary outcomes were the total scores on the Fibromyalgia Impact Questionnaire (FIQ), pain severity, and number of tender points. The secondary outcomes were changes in fatigue, stiffness, anxiety, and depression. Standardized mean difference (SMD), 95% confidence intervals (CI), and P values were calculated for outcome analysis. Results: We identified 9 RCTs that included 325 fibromyalgia patients undergoing LLLT or placebo laser treatment with or without an exercise program. The meta-analysis showed that patients receiving LLLT demonstrated significantly greater improvement in their FIQ scores (SMD: 1.16; 95% CI, 0.64-1.69), pain severity (SMD: 1.18; 95% CI, 0.82-1.54), number of tender points (SMD: 1.01; 95% CI, 0.49-1.52), fatigue (SMD: 1.4; 95% CI, 0.96-1.84), stiffness (SMD: 0.92; 95% CI, 0.36-1.48), depression (SMD: 1.46; 95% CI, 0.93-2.00), and anxiety (SMD: 1.46; 95% CI, 0.45-2.47) than those receiving placebo laser. Furthermore, when compared with the standardized exercise program alone, LLLT plus the standardized exercise program provided no extra advantage in the relief of symptoms. On the other hand, the results of the only RCT using combined LLLT/LED phototherapy showed significant improvement in most outcomes except for depression when compared to placebo. When compared with pure exercise therapy, combined LLLT/LED phototherapy plus exercise therapy had additional benefits in reducing the severity of pain, number of tender points, and fatigue. Limitations: There were some limitations in this review, mostly because of the low-to-middle methodological quality of the selected studies; for example, there was no clear allocation process and only patients were blinded in most studies. In addition, one study used per-protocol analysis with a 20% loss to follow-up. On the other hand, the differences in laser types, energy sources, exposure times, and associated medication status in these studies may have resulted in some heterogeneity. Conclusions: Our results provided the most up-to-date and relevant evidence regarding the effects of LLLT in fibromyalgia. LLLT is an effective, safe, and well-tolerated treatment for fibromyalgia. Key words: Low-level laser therapy, fibromyalgia, meta-analysis, FIQ, pain, tender points, exercise

Whole-Body Photobiomodulation Therapy for Fibromyalgia: A Feasibility Trial

“…Pain reduction was clinically significant [85,88] with significant improvement in painintensity and pain-interference 'categories' [79,112]. This demonstrates consistency with the aforementioned FM trials [57,91,134] and was also supported by the reduction in painrelated medication reported in this study. Emerging evidence describes a small-fibre neuropathy associated with FM pain [23].…”

“…Self-reported stiffness demonstrated a clinically significant improvement of 34.3%; more than double the MCID of 13% for FIQ stiffness [10]. A significant improvement in stiffness was observed in localised PBMT meta-analyses in FM patients [134]. Quantification of taut muscle bands in stiffness assessment is one possibility [8], however, there is no consensus regarding standardisation of muscle groups to be assessed.…”

“…recruitment, adherence, treatment fidelity) [41]. Data from previous work surrounding localised PBMT in FM was used to inform sample size [134]. Our chosen sample size takes into account the study populations' number of visits at our clinics, study objectives, and recommendations for the sample size calculations in pilot and feasibility trials [69,73,78,90].…”

Efficacy of class IV laser in the management of musculoskeletal pain: a systematic review

“…Favourable results observed in MSD of nonarticular origin are promising and encourage us to con tinue developing new RCTs under these conditions. This is also supported by research conducted with LILT that verifies its use in pain management in myofascial conditions and tendinopathies [50][51][52].…”

Green light analgesia in mice is mediated by visual activation of enkephalinergic neurons in the ventrolateral geniculate nucleus

“…Exposure to light of specific wavelengths and intensities has shown some effects in the management of various health conditions, such as cancers ( 2 ), skin diseases ( 3 ), sleep disorders ( 4 ), and affective disorders ( 5 ). Recently, low-intensity laser/light therapy has been used for the management of various pain conditions, including chronic nonspecific low back pain ( 6 ), fibromyalgia pain ( 7 ), migraine headaches ( 8 ), and neuropathic pain ( 9 ). Among the colors and wavelengths available for such therapy, most studies have reported the beneficial effects of green light ( 10 ).…”