ХРОНИЧЕСКИЕ БОЛЕВЫЕ СИНДРОМЫ В СТАРЧЕСКОМ ВОЗРАСТЕ И РОЛЬ СУБСТАНЦИИ Р. ПРИ ДАННОЙ ПАТОЛОГИИ

Abstract

ABSTRACT AIM. To investigate chronic pain syndromes in old age and evaluate the clinical significance of substance P in this pathology. MATERIAL AND METHODS. The study enrolled 68 patients over the age of 75 years with the presence of musculoskeletal pain of any origin for at least 3 months. The mean age of the patients reached 81.9 ± 5.8 years (from 75 to 100 years), most of them were women (85.3%). In this study, the severity of pain was assessed using a visual analogue scale (VAS), and the type of pain was analyzed using questionnaires and scales: DN4, PainDetect, Fibromyalgia Identification Questionnaire (FIRST), Central Sensitization Questionnaire, McGill Pain Questionnaire. The blood concentration of substance P was determined by enzyme immunoassay. RESULTS AND DISCUSSION. The severity of pain syndrome on the VAS scale reached 6.3 ± 2.2 points. The mean scores for DN4 were 3.9 ± 2.1 points, and for PainDetect — 14.7 ± 9.4 points. The mean value of the FIRST questionnaire for diagnosing fibromyalgia was 3.5 ± 1.6 points, and the McGill questionnaire was 69.8 ± 43.7 points. The mean value of the central sensitization scale reached 44.3 ± 16.7 points. Pain syndrome was more severe in women: the mean VAS value in women was 6.4 ± 2.3, in men — 5.1 ± 1.2 points (p = 0.02). The severity of the neuropathic component of the pain syndrome in women was also higher: DN4 scores in women were 4.0 ± 2.1, and in men — 2.9 ± 1.7 points (p = 0.08), and PainDetect — 15.7 ± 9.4 and 8.6 ± 6.4 points, respectively (p = 0.02). The mean values of the screening questionnaire for diagnosing fibromyalgia in women reached 3.7 ± 1.5 points, and in men — 2.7 ± 1.5 points (p = 0.07). In the group of women, the mean McGill questionnaire scores were 74.2 ± 45.2, in men — 45.3 ± 23.6 points (p = 0.006). The mean values of the central sensitization questionnaire for women were: 46.1 ± 16.3, and for men — 34.2 ± 15.5 points (p = 0.03). However, no significant differences in the severity of depression were recorded in women and men: 6.2 ± 2.8 and 5.0 ± 3.4 points, respectively (p = 0.3). The mean concentration of substance P in the study group was 222.6 ± 92.9 pg/ml, varying from 74 to 529 pg/ml. In men, the mean blood concentration of substance P reached 267.1 ± 85.2 pg/ml, in women — 214.2 ± 92.7 pg/ml (p = 0.02). An inverse correlation was registered between the blood concentration of substance P and the age of patients (r = −0.31; p = 0.02). No significant relationships were found between the blood concentration of substance P and the values of all pain questionnaires. Significant correlations were registered between VAS and DN4 (r = 0.29; p = 0.01), PainDetect (r = 0.41; p = 0.004), McGill questionnaire (r = 0.53; p < 0.0001) and central sensitization questionnaire (r = 0.3; p = 0.01). There was no significant correlation between the severity of pain according to VAS and the severity of depression (r = 0.16; p = 0.21). The severity of depression correlated with indicators of DN4 (r = 0.31; p = 0.01), FIRST (r = 0.26; p = 0.03), McGill questionnaire (r = 0.29; p = 0.02) and central sensitization questionnaire (r = 0.5; p < 0.0001). There was a direct correlation between the age of patients and indicators of DN 4 (r = 0.24; p = 0.05) and the central sensitization questionnaire (r = 0.25; p = 0.04). CONCLUSION. The study results suggest the presence of severe chronic pain syndrome of various types in old patients and longlivers. Significant relationships were found between pain indicators assessed using different scales and questionnaires. In this study, no significant correlations were established between the blood concentration of substance P and pain parameters. KEYWORDS: pain, old age, substance P, questionnaires, scales, neuropathic, depression