Objective: Pain currently plays a subordinate role in the clinical care of patients with ALS. We aim to examine epidemiological and clinical characteristics of pain as well as its impact throughout the disease course.
Methods: During a longitudinal follow-up at three time points, 151 ALS patients from three German outpatient clinics completed the Brief Pain Inventory, ALS-Functional Rating Scale-Extension and ALS Depression Inventory. Analysis of variance and covariance with repeated measures were performed.
Results: Pain was prevalent in 56% of the 151 patients at baseline and in 70% of the remaining 40 patients at the third survey. Of the 28 patients with pain who participated in all three surveys, about two thirds suffered from an average pain intensity corresponding to at least moderate pain on the numerical rating scale (NRS ≥ 4). Patients reported different pain qualities and localized the pain most frequently in the extremities, back and neck. Pain moderately impaired the functions of daily living. Pain intensity, pain quality and pain-related impairment did not significantly change over time. One third of the patients suffered from clinically relevant depressive symptoms. However, there was no conclusive evidence of a link between pain intensity and depressive symptoms.
Conclusion: Pain is frequent and constitutes an additional strain on ALS patients who have to endure a rapidly progressive and severely debilitating disease. This study contributes to better understanding of the characteristics of pain and its impact on ALS patients throughout the disease course and may thus help to more effectively address this symptom.
Keywords: Amyotrophic lateral sclerosis; longitudinal study; motor neuron disease; pain.