Validation of electroencephalic cordance for diagnosis and evaluation of fibromyalgia patients

Resumen

Cordance is a recent refinement of the quantitative EEG (QEEG) that has been successfully applied to various diseases and clinical situations, specially in prognosis and response to treatments. In this Thesis, the central objective has been the use of cordance, along with QEEG, for the neurophysiological analysis of a sample of patients with fibromyalgia (FM), seeking the future application of these techniques as a new method of body pain assessment, early diagnosis, response to treatment, and clinical management of these patients. To assess the validity of the electroencephalic cordance in FM, three studies were performed. In the first study (Patients vs. Controls) a group of FM patients was compared with another group of subjects free of the disease (controls). In the second study (Psychotherapy Acceptance and Commitment) and the third one (Memantine), the same group of FM patients were investigated before and after application of acceptance and commitment therapy, and before and after treatment with memantine. The results obtained are promising regarding the use of QEEG in diagnosis, both ratios theta/alpha and beta/alpha, and the electroencephalic cordance; as patients with poor diagnosis showed values of the ratios and of the prefrontal cordance in the theta band significantly higher. The results of this study suggest, more specifically, that electroencephalic cordance can predict the response to treatment of painful symptoms in fibromyalgia through acceptance and commitment therapy. Hence, the QEEG may be useful to justify the quality of this type of psychological therapies and to contribute to a better organization and individualized care of patients, according to the results provided by the QEEG. Likewise, the results of this study suggest that electroencephalic cordance can predict response to treatment of fibromyalgia by memantine. Further development of QEEG and cordance in this regard could lead to better clinical management of FM. However, larger and more complex studies are needed to replicate the current results and determine the reliability of cordance concerning the response to this medication. QEEG also continues to be seen as a useful diagnostic tool, as it is able to show significant differences between patients and controls, and among patients with poor diagnoses. Its qualities of versatility, low cost, non-invasiveness and ability for discrimination, configure it as and excellent tool for neurological diseases, even the most complex ones, such as fibromyalgia. Cordance, since its inception just over a decade, has been an efficient low cost tool for QEEG testing. Its noninvasive nature and portability make QEEG even easier to may be used to evaluate the effectiveness of therapeutic techniques and drug treatments in future research projects. This study represents a first step in our country for dissemination and acceptance of cordance as a method of diagnosis and classification of fibromyalgia and other neuropsychiatric disorders.