Abstract Introduction Fibromyalgia is a complex, generalized, and diffuse chronic musculoskeletal pain. Pharmacological approaches are widely used to relieve pain and increase quality of life. Low-Dose Naltrexone (LDN) was shown to increase the nociceptive threshold in patients with fibromyalgia. Transcranial Direct Current Stimulation (tDCS) is effective for pain management. Objective The purpose of this study was to evaluate the analgesic and neuromodulatory effects of a combination of LDN and tDCS in patients with fibromyalgia. Methods This was a randomized, double-blinded, parallel, placebo/sham-controlled trial (NCT04502251; RBR-7HK8N) in which 86 women with fibromyalgia were included, and written informed consent was obtained from them. The patients were allocated into four groups: LDN + tDCS (n = 21), LDN + tDCS Sham (n = 22), placebo + tDCS (n = 22), and placebo+tDCS Sham (n = 21). The LDN or placebo (p.o.) intervention lasted 26 days; in the last five sessions, tDCS was applied (sham or active, 20 min, 2 mA). The following categories were assessed: sociodemographic, Visual Analog Pain Scale (VAS), Pain Catastrophizing Scale (PCS), State-Trait Anxiety Inventory (STAI), Fibromyalgia Impact Questionnaire (FIQ), Beck Depression Inventory (BDI-II), Profile of Chronic Pain Scale (PCP:S), Pain Pressure Threshold (PPT), and Conditioned Pain Modulation (CPM). Blood samples were collected to analyze BDNF serum levels. Results At baseline, no significant difference was found regarding all measurements. VAS pain was significantly reduced in the LDN + tDCS (p = 0.010), LDN + tDCS Sham (p= 0.001), and placebo+tDCS Sham (p= 0.009) groups. In the PCP:S, the LDN+tDCS group showed reduced pain frequency and intensity (p= 0.001), effect of pain on activities (p= 0.014) and emotions (p= 0.008). Depressive symptoms reduced after all active interventions (p > 0.001). Conclusion Combined LDN+tDCS has possible benefits in reducing pain frequency and intensity; however, a placebo effect was observed in pain using VAS, and further studies should be performed to analyze the possible association.

Resumo Objetivo O objetivo deste estudo foi avaliar o perfil nociceptivo e o uso de analgésicos em pacientes submetidos à cirurgia de reparo do manguito rotador. Além disso, os limiares nociceptivos e a integridade do sistema inibidor descendente, o catastrofismo da dor e a prevalência de dor nociceptiva ou neuropática também foram analisados. Métodos Este estudo foi aprovado pelo Comitê de Ética da Universidade La Salle (1.325.433/2015). Quarenta pacientes (maiores de 18 anos) submetidos à cirurgia de reparo do manguito rotador (divididos entre aqueles com lesões pequenas e grandes) participaram do estudo. Os instrumentos utilizados foram o Questionário Sociodemográfico, a Escala Funcional de Dor, a Escala Visual Análoga (EVA), o Teste Sensorial Quantitativo (QST) e a Tarefa de Modulação Condicionada da Dor (CPM). Resultados Os pacientes apresentaram diferenças significativas nos limiares de dor e QST de calor (teste t de amostras independentes) e qualidade do sono, humor e ansiedade (teste t pareado) nos grupos pré-operatórios. Houve uma correlação significativa entre CPM pré-operatória e EVA pós-operatória (correlação de Pearson). Observou-se que, no período pré-operatório, 38 pacientes utilizavam analgésico de forma contínua. Além disso, no período pós-operatório, o uso de opioides foi maior nos pacientes com lesões pequenas (13 pacientes) em comparação àqueles com lesões grandes (nove pacientes). Conclusão Os pacientes com lesão do manguito rotador não apresentaram alterações no sistema inibidor descendente, mas sim alterações nos limiares de dor, o que pode interferir no período pós-operatório e estar relacionado ao consumo de analgésicos.

Abstract Objective This study aimed to evaluate the nociceptive profile and the intake of analgesic drugs of patients submitted to rotator cuff repair surgery. Also, to evaluate the nociceptive thresholds and the integrity of the descending inhibitory system, pain catastrophism and prevalence of nociceptive or neuropathic pain. Methods Approved by the Ethics Committee of La Salle University (1.325.433/2015). 40 patients (>18 years old) who underwent rotator cuff repair surgery (divided in small and large injuries) were recruited. The used instruments were: Sociodemographic Questionnaire, Functional Pain Scale, Visual Analogue Scale (VAS), Quantitative Sensory Test (QST) and Conditioned Pain Modulation Task (CPM). Results Patients had a significant difference in pain thresholds QST heat (independent samples t test) and quality of sleep, mood and anxiety (paired t test) in groups preoperative. There was a significant correlation between preoperative CPM and postoperative VAS (Pearson Correlation). It was observed that, in preoperative, 38 patients used analgesics continuously. Besides that, in postoperative, use of opioid drugs was higher in patients with small injury (13 patients) than in those with large injury (9 patients). Conclusion Therefore, patients with rotator cuff injuries did not present alterations in the descending inhibitory system, but showed alterations in pain thresholds, which may interfere in the postoperative period and still be related to the consumption of analgesics.

Abstract Fibromyalgia is a syndrome characterized by chronic pain related to the musculoskeletal system. Patients feel incapable and show catastrophic thoughts (exaggeration of the sensations) related to painful events. This study aimed to compare catastrophic thoughts of pain between daughters of women with fibromyalgia and daughters of women without fibromyalgia, no daughter having the syndrome. It was a case-control study in which 76 women were included: 38 daughters of women diagnosed with fibromyalgia (case group), and 38 daughters of women without fibromyalgia (control group). The Brazilian versions of the Profile of Chronic Pain: Screen, the Pittsburgh Sleep Quality Index, the Pain Catastrophizing Scale, Resilience Scale, Beck Depression Inventory-II, and the State-Trait Anxiety Inventory were used. Data were tabulated and analyzed using SPSS 20.0. Continuous variables were compared between the groups using the Mann-Whitney U test or Student’s t-test for independent samples. A significant difference was considered at p< 0.05. Regarding catastrophism, the case group had higher total catastrophism compared to the control group (p= 0.025). Daughters of patients with fibromyalgia showed higher rumination and magnification levels related to pain (p= 0.028 and p= 0.007, respectively) but did not show hopelessness. This study concludes that daughters of women with fibromyalgia are more likely to have symptoms of fibromyalgia due to their visualization of the syndrome. This indicates that emotional aspects may induce changes, and additional research on an individual basis is necessary.