Neurotransmitter imbalances and psychological dysfunctions as predicative factors of postoperative chronic pain syndrome in operative gynecology center

Chronic postoperative pain is one of the urgent medical and social problems of operative gynecology. The problem is preconditioned by a high prevalence rate, a significant impact on the outcomes of operative therapy and, as a consequence, patients' quality of life. The goal of the paper is to study the role of preoperative neurotransmitter and psychoemotional dysfunctions in the development of postoperative chronic pain syndrome in an operative gynecology center. Materials and Methods. The study enrolled 156 patients aged 18-45 years who underwent planned surgical treatment for gynecological pathology. Patients were subsequently divided into 2 groups: Group 1 - women with postoperative chronic pain syndrome; Group 2 - women without chronic postoperative pain syndrome. The authors conducted general clinical examination, and also determined the levels of y-aminobutyric acid and ß-endorphin in serum of patients using enzyme-linked immunosorbent assay. A visual analogue scale was used to assess quantitative characteristics of pain syndrome. Qualitative characteristics of pain syndrome were assessed according to the McGill Pain Questionnaire. HAM-A and HDRS were used to assess psychoemotional state. Results. Postoperative chronic pain was observed in 39.7 % of patients 12 months after surgery. In the preoperative period, a pain syndrome was registered in all patients. However, there were no significant intergroup differences in its severity. Statistically significant predominance of the affective scale indicators was revealed in the pain syndrome structure in Group 1, while Group 2 demonstrated predominance of the sensory scale indicators (p=0.003). Group 1 demonstrated more pronounced changes in GABA and ß-endorphin levels. An inverse correlation was found between the level of ß-endorphin and the affective and evaluative McGill questionnaire scales. Various affective pathologies were verified in Group 1. However, depressive disorders dominated. Group 2 demonstrated only subdepression and individual clinically unformed anxiety symptoms. The authors found out depressive disorder correlation with the severity of preoperative pain syndrome according to visual-analogue scale, McGill questionnaire affective scale, and ß-endorphin concentration. Conclusion. Neurotransmitter disorders and psychological dysfunctions affect the formation of postoperative chronic pain syndrome. There is a correlation between chronic postoperative pain syndrome, preoperative ß-endorphin concentration (r=-0.70; p=0.028), and the severity of depressive disorders (r=0.65; p=0.012), which confirms their role as non-specific prognostic markers while monitoring the postoperative chronic pain syndrome.