Efecto de la hipnosis combinada con estimulación transcraniana de corriente continua en la percepción del dolor y en la función del sistema descendente en sujetos sanos : ensayo clínico randomizado ciego cruzado controlado con uso simulado

• Ano de defesa: 2019
• Autor(a) principal: Serrano, Gerardo Vinicio Beltran
• Orientador(a): Caumo, Wolnei
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: spa
• Palavras-chave em Português: Hipnose; Estimulação transcraniana por corrente contínua; Dor; Ensaio clínico controlado aleatório
• Link de acesso: http://hdl.handle.net/10183/202518

Pain is a public health problem, associated with suffering and functional disability. Its consequences remain in the personal and social life of the patient, leading to significant changes in their interpersonal, work, family and social relationships, decreasing the ability to perform daily activities. Pharmacological techniques present a poor therapeutic response in most patients, many of them end up becoming polymedicated and refractory to treatment. The nonpharmacological techniques are promising and have positive scientific evidence of its effects on pain, with an increase in the number of studies with neuromodulatory techniques such as acupuncture, electroacupuncture, TMS, tDCS and hypnosis. Among those that stand out most are the transcranial direct current stimulation (ETCC) and the hypnotic analgesia suggestion. Considering the limitations of pharmacological options in the treatment of chronic pain, new research should be oriented to promote progress in the process and understanding of the mechanism of pain, providing new therapeutic possibilities with the potential to modify the dysfunctional neuroplasticity processes associated with chronic pain, aiming at clinical improvement. Objectives: There were two objectives: (I) To determine whether the suggestion of hypnotic analgesia and the transcranial direct current stimulation (tDCS) have a differential effect on the perception of pain. We hypothesized that transcranial direct current stimulation would be more effective than hypnotic analgesia in changing the descending pain modulating system (DPMS), whereas hypnotic suggestion would have a greater effect on quantitative sensory tests. (ii) Understand the combined effect of transcranial direct current stimulation (a tDCS) and the hypnotic analgesia suggestion on pain perception and the descending pain modulating system. This research also aims to determine if the effect of a-tDCS and the suggestion of hypnotic analgesia in psychophysical measures (CPM-task, HPT, HPTo and CPT) could be associated with the serum level of BDNF. We hypothesized that the combined therapy (a-tDCS / hypnotic analgesia suggestion) would be more effective in pain perception and DPMS than individual interventions (a-tDCS or hypnotic analgesic suggestion). Methods: Healthy women aged 18 to 45 years were included, with a high susceptibility to hypnosis, according to the Waterloo-Stanford Group hypnotic susceptibility scale, Form C. Subjects received an anodal transcranial direct current stimulation (a-tDCS) on left DLPFC (2 mA for 20 min) and hypnotic analgesia (20 min). In study I: 24 randomized and assigned women were included in one of the two intervention groups with a cross-sectional distribution for one of the groups: (1) a-tDCS (2mA, 20min) or (2) Hypnotic suggestion (20min). In study II: 48 randomized and assigned women were included in one of the four intervention groups: (1) atDCS (2mA, 20min), (2) Hypnotic analgesia suggestion (20min), (3) a-tDCS / Hypnotic analgesia suggestion (2mA, 20min) or (4) s-tDCS / Hypnotic analgesia suggestion (0mA, 20min). After the first intervention, the participants returned for a second experimental session to receive an alternative intervention. Group 1 went on to receive group 2 intervention and vice versa. The same was applied between group 3 and 4. Results: The results of the study I revealed that only the hypnotic suggestion produced changes that are statistically significant from pre to pos intervention in the following measures: heat pain threshold, heat pain tolerance, cold pressure test and neurotrophic factor derived from the brain in serum. The analysis showed a significant main effect for the treatment (F = 4.32, P = 0.04) when we compared the delta (Δ) task of the conditioned pain modulation between the groups of transcranial direct current stimulation and hypnotic suggestion. In addition, the change in the neurotrophic factor derived from the brain correlated positively with the task of conditioned pain modulation. The results of study II demonstrated that hypnotic suggestion alone or combined with a- or s-tDCS has been shown to reduce the efficiency of the descending pain modulation system when compared to a-tDCS alone. The use of a-tDCS improved the DPMS by 53.70% compared to a-tDCS / Hypnotic suggestion. The hypnotic suggestion combined with a-TDCS or s-TDCS increased the HPTo when compared with a-TDCS alone. While in s-tDCS / Hypnotic suggestion HPTo increased almost 16 times. The combination of a-tDCS and the hypnotic suggestion increased the CPT by almost six times compared to a-tDCS alone and by 156% compared to the hypnotic suggestion alone. In addition, the highest levels of BDNF in the baseline correlated positively with a greater change in the CPTo value in the a-tDCS and in the CPT with a-tDCS / Hypnotic suggestion. Conclusions: The results confirm a differential effect between hypnotic suggestion and transcranial direct current stimulation in pain measurements. They suggest that the impact of the interventions has differential neural mechanisms, since the hypnotic suggestion improved the perception of pain, whereas the stimulation by transcranial direct current increased the inhibition of the descending pain modulating system. While the combined effect did not improve the efficiency of inhibition in the DPMS.