Thalamus volume reduction and asymmetry as markers of MS progression, pain characteristics and low quality of life in patients with multiple sclerosis

Abstract

Objective — to analyze the relationship between changes in thalamic volumes in patients with MS with the characteristics of the clinical course of MS, pain syndromes, and patient’s quality of life and to evaluate the possibility of using changes in thalamic volumes to objectify these characteristics. Methods and subjects. 17 patients with a confirmed diagnosis of multiple sclerosis were examined at the Lviv Regional Multiple Sclerosis Center. Complaints and anamnesis were collected, medical documentation was analyzed and neurological and general medical examination of patients was performed. The SF‑36 questionnaire was used to assess the quality of life. The HADS questionnaire was used to assess anxiety and depression. Characteristics of pain syndromes were evaluated using Pain Detect, VAS, and SF‑MPQ‑2 questionnaires. MRI scans were performed, followed by processing with the VolBrain algorithm with further analysis of thalamic volumes. Results. The median age in the sample was 37.0 [35.0; 46.0] years. Among patients there were 82.35 % women, and 17.65 % men. The disease duration was from 0 to 25 years, the median was 12 [5.0; 18.0] years. EDSS scale score was 3.5 [3.0; 4.0]. The median number of MS relapses before the time of examination in the history of patients is 12.0 [8.0; 18.0]. Analysis of the MS course characteristics showed that the increase in the number of relapses in general (rs = –0.728, p = 0.001) and relapses over 3 years (rs = –0.557, p = 0.020) were associated with a decrease in thalamic volume, while the relationship with the number of relapses in the last year, duration of MS and EDSS score were not found. When analyzing the relationship with pain characteristics, a statistically significant correlation (rs = –0.519, p = 0.037) of asymmetry between the right and left thalamus and the neuropathic component of pain (Pain Detect score) was found. There were also statistical significance between an increase in right and left thalamic volumes and an increase of pain intensity (VAS score) in average and the neuropathic pain component (SF‑MPQ‑2 score). The asymmetry between the right and left thalamus had a pronounced relationship with a decrease in the physical component of quality of life (rs = –0.679, p = 0.003), namely its characteristics such as physical functioning (rs = –0.697, p = 0.002). Also, physical functioning has a significant relationship with the volume of the thalamus (rs = +0.509, p = 0.037), namely the left thalamus (rs = +0.592, p = 0.012). Conclusions. Changes in the thalamic volumes are a promising marker for assessing MS progression, pain characteristics, and quality of life in MS patients. Decreased thalamic volume in MS patients can be considered a marker of MS progression (the number of exacerbations in general and the number of exacerbations in recent years). Higher average pain intensity and the neuropathic component of pain are associated with less right and left thalamuses atrophy in MS patients. The asymmetry of thalamic volumes in patients with MS in the direction of reduction of the left thalamus volume relative to the right thalamus volume can be considered as a predictor of the reduced physical component of quality of life, in particular, physical functioning.