Rest-Activity Rhythm, Pain, and Motor Activity in Multiple Sclerosis.

BACKGROUND: Although the relationships among physical disability, mood disorders, and pain are well described in multiple sclerosis (MS), little is known about whether those symptoms are associated with sleep disturbances. METHODS: Forty-six patients with MS experiencing pain participated. Sleep was indirectly measured by assessing rest-activity rhythm via actigraphy: interdaily stability, intradaily variability, and relative amplitude. Pain was assessed using visual and verbal analog scales, mood by the Beck Depression Inventory and Symptom Checklist-90, and physical disability by the Expanded Disability Status Scale. RESULTS: Incorporating mood, pain, and physical disability into 1 regression model resulted in a significant association with interdaily stability. CONCLUSIONS: Compared with intradaily variability and relative amplitude, interdaily stability seems to be the most vulnerable actigraphy variable for mood disturbances, pain, and physical disabilities.

Pain, cognition and disability in advanced multiple sclerosis.

OBJECTIVES: In patients with multiple sclerosis (MS), a relationship between physical disability and pain has been observed. In addition a relationship between physical disability and cognition in MS has been suggested. However, cognitive functions and pain appear not to be correlated in MS patients. Therefore, we examined whether a possible relationship between pain and cognitive functioning may exist, and if so, if such a relationship is mediated by physical disability. METHODS: Forty-five MS patients with chronic pain, and in an advanced stage of the disease were included. Physical disabilities were assessed by the Expanded Disability Status Scale (EDSS). Episodic memory was assessed by means of the Eight Words test, and Face and Picture Recognition. Executive functions (EF) were examined by Digit Span Backward for working memory, and the Rule Shift Cards and Category Fluency test for cognitive flexibility. Pain Intensity and Pain Affect were assessed by means of visual analogue scales and one verbal pain scale and mood (depression, anxiety) by the Beck Depression Inventory and the Symptom Check List (SCL-90). The research questions were analyzed by means of regression analyses and the Sobel test for mediation. RESULTS: A significant relationship was found between Pain Affect and EF, but that relationship was not mediated by physical disabilities (EDSS). In addition, Pain Intensity and EF showed a significant relationship but only in combination with physical disabilities (EDSS). Finally, mood was related to pain affect. DISCUSSION: The findings suggest that the lower the EF, exclusively or in combination with more physical disabilities, the more the patient may suffer from pain. IMPLICATIONS: The more one is cognitively and physically impaired, the more one might suffer from pain, and, the less one is able to communicate pain. The latter could put MS patients at risk for underdiagnosing and undertreatment of pain.

Sensory Function and Chronic Pain in Multiple Sclerosis.

Objective: To examine whether hypoesthesia and chronic pain are related in patients with MS. Methods: Sixty-seven MS patients with pain and 80 persons without MS were included. Sensory functioning was tested by bedside neurological examination. Touch, joint position (dorsal column-medial lemniscus pathway), temperature sense, and pain (spinothalamic tract) were tested. Pain intensity was measured by the Colored Analogue Scale (CAS Intensity) and the Faces Pain Scale (FPS); pain affect was also measured by CAS Affect and Number of Words Chosen-Affective (NWC-A). Mood was assessed with the SCL-90 anxiety and depression subscales and the Beck Depression Inventory (BDI). Results: A significant negative relationship was found between pain intensity and the function of the dorsal column-medial lemniscal pathway, but not with the spinothalamic tract. Conclusion: In addition to the already known relation between hyperesthesia and pain, hypoesthesia for touch and joint position also seems to be related to chronic pain in MS patients.