Chronic Pain in Multiple Sclerosis Patients: Utility of Sensory Quantitative Testing in Patients with Fibromyalgia Comorbidity

Abstract

Background: Lower thermal and discomfort thresholds may predispose multiple sclerosis (MS) patients to chronic pain, but a possible effect of fibromyalgia (FM) comorbidity has never been investigated. Aims were to investigate the thermal and discomfort thresholds in the evaluation of pain intensity between MS patients with FM (PFM+) and MS patients with pain not associated to FM (PFM−). Methods: One hundred thirty three MS patients were investigated for chronic pain. FM was assessed according to the 1990 ACR diagnostic criteria. An algometer was used to measure the thresholds in the patients and 60 matched healthy subjects. Results: Chronic pain was present in 88 (66.2%) patients; 12 (13.6%) had neuropathic pain, 22 (17.3%) were PFM+ and 65 (48.9%) PFM−. PFM+ were predominantly female (p = 0.03) and had a greater EDSS (p = 0.01) than NoP; no other significant differences emerged than PFM−. The thresholds were lower in MS patients than controls (p < 0.01), mainly in the PFM+. FM severity influenced the thermal threshold (p < 0.001), while the female gender influenced the discomfort threshold (p < 0.001). Conclusion: Thermal and discomfort thresholds were lower in patients than controls and were the lowest in PFM+. Their more severely impaired thermal threshold supports a neurophysiological basis of such association.

Increased risk of non-multiple sclerosis demyelinating syndromes in patients with preexisting septicaemia: a nationwide retrospective cohort study

“…The finding is in agreement with a previous study 20. In our study population, the prevalence of comorbidity such as fibromyalgia was higher than giant cell arteritis, and these middle age septicaemia patients with fibromyalgia are relatively prone to have demyelinating syndromes, including MS 21. This may explain in part the observation that the 45–64 age group with pre-exsiting septicaemia had the highest adjusted HR of developing NMSDS.…”

Unique features of central neuropathic pain in multiple sclerosis: Results of a cluster analysis

“…Fewer patients in both the CNP and the MSP groups were employed compared with the pain‐free group, perhaps due to the added disability imposed by chronic pain (Grant et al, 2019). Both the CNP and the MSP groups had higher EDSS scores compared with the pain‐free group, in line with previous reports (Heitmann et al, 2015; Kahraman et al, 2019; Pompa et al, 2015; Truini et al, 2012) which may result from greater fatigue, disability and depression due to the pain (Heitmann, 2020; Kahraman et al, 2019). Nevertheless, EDSS or disease duration did not affect the differences between the groups in the sensory testing.…”

“…However, considering that sensory impairment is an integral sign of MS and may occur regardless of chronic pain, it is not clear whether these features are unique to CNP or characterize all MS‐related chronic pain types. Indeed, MS patients with chronic pain of unspecified origins had thermal and pinprick thresholds similar to those of pain‐free MS patients (Fernández‐de‐las‐Peñas et al, 2015; Grasso et al, 2008; Pompa et al, 2015).…”

“…The management of CNP in MS is challenged by the difficulty in its identification and hence in providing effective treatment. MS alone produces ample and widespread sensory alterations which may mask those related to CNP (Grasso et al, 2008; Pompa et al, 2015; Scherder et al, 2018). Furthermore, widespread pain, often of musculoskeletal origin (due to disuse/overuse injuries, abnormal posture, assistive technology usage, and decreased mobility) (Truini et al, 2013) may further complicate the distinction of CNP from other pain types (Feketová et al, 2017; Kahraman et al, 2019).…”

Clinical perspective on pain in multiple sclerosis

“…45 The Pain Interference Scale of the Brief Pain Inventory, the Graded Chronic Pain Disability Score, 41,47 and the PES are validated for MS. 48 The Pain Interference Scale of the Brief Pain Inventory includes several components and seems sufficiently comprehensive to evaluate the interference of pain in MS. Algometer (evaluating thermal and pressure pain thresholds) usage in studies is scarce. 29,49,50 Several studies assessed co-existing sensory complaints of MS pain by Quantitative Sensory Testing (evaluating perception of vibration, touch, warm, cold, and heat pain). 18,25 In order to discriminate neuropathic pain and nociceptive pain, neurophysiological tests are recommended to use, such as somatosensory evoked potentials and laser evoked potentials.…”