Pain in patients with multiple sclerosis: a complex assessment including quantitative and qualitative measurements provides for a disease-related biopsychosocial pain model

Journal of Pain Research Dovepress open access to scientific and medical research O r i g i n al R e s e ar c h Journal of Pain Research downloaded from https://www.dovepress.com/ by 54.37.163.172 on 12-Jul-2018 For personal use only. Open Access Full Text Article Pain in patients with multiple sclerosis: a complex assessment including quantitative and qualitative measurements provides for a disease-related biopsychosocial pain model This article was published in the following Dove Press journal: Journal of Pain Research 1 August 2011 Number of times this article has been viewed Dominik Michalski 1,* Stefanie Liebig 1,* Eva Thomae 1,2 Andreas Hinz 3 Florian Then Bergh 1,2 Department of Neurology, Translational Centre for Regenerative Medicine (TRM), 3Department of Medical Psychology and Medical Sociology, University of Leipzig, Leipzig, Germany 1 2 *These authors contributed equally Background: Pain of various causes is a common phenomenon in patients with Multiple Sclerosis (MS). A biopsychosocial perspective has proven a useful theoretical construct in other chronic pain conditions and was also started in MS. To support such an approach, we aimed to investigate pain in MS with special emphasis on separating quantitative and qualitative aspects, and its interrelation to behavioral and physical aspects. Materials and methods: Pain intensity (NRS) and quality (SES) were measured in 38 consecutive outpatients with MS (mean age, 42.0 ± 11.5 years, 82% women). Pain-related behavior (FSR), health care utilization, bodily complaints (GBB-24) and fatigue (WEIMuS) were assessed by questionnaires, and MS-related neurological impairment by a standardized neurological examination (EDSS). Results: Mean pain intensity was 4.0 (range, 0–10) and mean EDSS 3.7 (range, 0–8) in the overall sample. Currently present pain was reported by 81.6% of all patients. Disease duration and EDSS did not differ between patients with and without pain and were not correlated to quality or intensity of pain. Patients with pain had significantly higher scores of musculoskeletal complaints, but equal scores of exhaustion, gastrointestinal and cardiovascular complaints. Pain intensity correlated only with physical aspects, whereas quality of pain was additionally associated with increased avoidance, resignation and cognitive fatigue. Conclusion: As in other conditions, pain in MS must be assessed in a multidimensional way. Further research should be devoted to adapt existing models to a MS-specific model of pain. Keywords: pain intensity, quality of pain, pain-related behavior, bodily complaints, multiple sclerosis Introduction Correspondence: Dominik Michalski University of Leipzig, Department of Neurology, Liebigstr. 20, 04103 Leipzig, Germany Tel +49 341 972 4206 Fax +49 341 972 4257 Email dominik.michalski@medizin. uni-leipzig.de submit your manuscript | www.dovepress.com Dovepress http://dx.doi.org/10.2147/JPR.S20309 Powered by TCPDF (www.tcpdf.org) Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system that often leads to long-term physical disability.1 Throughout the course of the disease, pain is a common, varying symptom and a significant problem.2 In 23% of patients with MS, pain was found as part of the presenting symptoms at disease onset.3 Previous studies have reported remarkable pain prevalences up to 79.4% and 92% in patients with MS.4,5 Pain in MS patients can be caused directly by inflammatory attack on afferent fiber tracts, or indirectly by various sequelae of MS (eg, limb paresis, extrapyramidal or cerebellar syndromes, bladder dysfunction),1 leading to increased muscle tone with spasms, postural abnormalities, or urinary tract infections.2,6 In addition, drug treatment is a potential contributor to pain.6,7 On Journal of Pain Research 2011:4 219–225 219 © 2011 Michalski et al, publisher and licensee Dove Medical Press Ltd. This is an Open Access article which permits unrestricted noncommercial use, provided the original work is properly cited. Dovepress Journal of Pain Research downloaded from https://www.dovepress.com/ by 54.37.163.172 on 12-Jul-2018 For personal use only. Michalski et al the other hand, pain in MS influences many aspects of daily living2,8,9 (eg, important domains of health-related quality of life)10 and physical activity.11,12 The consequences of pain in MS should be assessed with a focus on psychosocial aspects – an issue that has received insufficient attention in numerous previous studies.2,13 The available data suggest that depression, pain behavior, health care utilization, coping behavior, and beliefs might be important determinants of pain.2,6,13–16 In other painful conditions – such as low back pain – biopsychosocial models, which describe interactions of bodily pain with cognitive, behavioral, and social variables, have proven useful in understanding the complex conditions of the disorder and guiding interventions.17–20 Kerns et al6,13 proposed a multidimensional model for pain in MS; amongst others, behavioral aspects have received more attention in this model. For example, muscle weakness can contribute to more generalized deconditioning and increased musculo skeletal complaints; these changes, in combination with fear of pain, contribute to avoidance behavior with a consecutive worsening of muscle weakness and thus additional pain.6 The usefulness of this analytical process in MS patients was underscored by a recent study by Motl et al,21 who focused on behavioral aspects, especially physical activity. They found that MS patients who were more physically active had lower scores of pain along with reduced depression and fatigue, as well as improved self-esteem. Comparable data were also presented by Turner et al.22 Another investigation showed a significant association of pain beliefs and coping strategies with pain intensity scores in patients with MS.15 Generally, previous studies in MS patients often assessed pain in a dichotomous way, providing the proportion of patients with and without pain.9–12 This was sometimes supplemented with quantifying pain intensity using rating scales.5,9–12,16,23 One aspect that has been incompletely addressed – especially in the field of neuropathic pain – is recording both pain intensity and quality of pain.24 The aims of the present study were (1) to investigate both pain intensity and quality of pain in MS patients – predominantly in a quantitative modality – and (2) to analyze their interrelations to physical (bodily complaints, fatigue) and behavioral factors (pain-related behavior, health care utilization), exploring the components of a biopsychosocial model applicable to MS. Materials and methods Study design and population In a prospective setting, unselected consecutive outpatients attending the Department of Neurology of the University of 220 Powered by TCPDF (www.tcpdf.org) submit your manuscript | www.dovepress.com Dovepress Leipzig in 2007 with (...truncated)