Efeitos da eletroestimulação transcraniana por corrente contínua sobre a dor, capacidade funcional submáxima e estado de humor em mulheres com dismenorreia primária

Abstract

Introduction: Primary dysmenorrhea (PD) is a chronic condition that negatively affects women's lives in many social, emotional and physical aspects. So far, drug therapy and thermotherapy have been the most effective means of treating dysmenorrhea, but these have undesirable adverse reactions or short-term local effects. Transcranial direct current electrical stimulation (tDCS) is a non-invasive cortical stimulation technique that promotes changes in brain functioning, and seems to have good effects on pain and functionality. To date, there are no studies of this therapy on the dorsolateral prefrontal cortex (DLPFC) in patients with PD. Objectives: The main objective is to investigate the effect of tDCS on the DLPFC on pain in patients with PD. The secondary outcomes were functionality and mood. Methods: A double blind randomized controlled clinical trial was carried out. 26 volunteers with PD were randomized into two groups. The tDCS group received therapy for 5 consecutive days, while the Sham group performed the same protocol, but the current was turned on for a period of 30 seconds and then turned off. tDCS was performed in the DLPFC, with an intensity of 2mA. Participants in both groups were assessed at two times: in the first 24 hours of the initial menstrual cycle (AV1), in the first 24 hours of the next menstrual cycle and after intervention (AV2). To evaluate the primary outcome, the numerical pain scale was used. For the secondary outcomes mood (affectivity and anxiety), and of functionality, were used the Hamilton anxiety rating scale, the positive and negative affect scale, and de six-minute walk test, respectively. Results: No significant interaction between intervention and time was found in the NRS [F (2.44) = 1.358, p = 0.26] and a significant effect of time was noted [F (2.44) = 4.446, p = 0.01] was found. The active group showed a significant reduction in anxiety (p = 0.03) with a mean difference of 5.12 (95% CI 0.79 to 11.05). There were no significant differences between positive and negative affect (p = 0.95 and p = 0.15, respectively). Submaximal aerobic performance was significantly higher in the active group [F (2.21) = 5.591, p = 0.02], with a mean difference of 70.87 (95% CI 8.53 to 133.21). Conclusion: tDCS in the DLPFC region appears in this study as a resource with satisfactory effect on functionality. This is effective in reducing anxiety, improving mood and functionality.