Effects of pain on cognitive function and mobility

摘要

Background: Chronic pain has been associated with impaired cognitive function as well as limitations in physical mobility in older adults. This study was conducted to determine whether acute pain that is typically self-diagnosed and self-treated with nonprescription analgesics also affects cognitive function or mobility. Methods: In this placebo-controlled, randomized study, generally healthy adults with recurrent acute joint, back, head, or menstrual pain underwent assessments of cognitive function (Axon Sports Priming Application, Cambridge Neuropsychological Test Automated Battery) and mobility (gait, time to stand, and grip force) during pain (≥5 out of 10 on Brief Pain Inventory – Short Form Q6) vs after pain resolution. Assessments during pain were made before and after treatment with paracetamol 500 mg, paracetamol 500 mg/caffeine 65 mg, or placebo. Primary and secondary outcomes, respectively, were the effects of pain on cognition and mobility vs the pain-free state. The effects of nonprescription analgesics on these outcomes were intended as an exploratory outcome but were not analyzed due to early termination of the study for breaches of Good Clinical Practice guidelines. Results: At termination, 54 individuals had been screened and 21 randomized (safety population). The primary analysis population (modified intent-to-treat) consisted of 20 participants with no inclusion/exclusion violations. Due to early termination, the study did not meet prespecified recruitment levels; therefore, no conclusions could be drawn regarding the effects of pain on cognitive performance or mobility. There were three treatment-emergent adverse events (placebo: reflux disease and hypercholesterolemia; paracetamol: pharyngeal erythema). Conclusion: Because the study was terminated before reaching prespecified recruitment levels, conclusions cannot be drawn regarding the effects of pain or relief from pain by analgesics on cognition or mobility. However, the methodology can serve as a model for addressing these important questions in future investigations. Safety results were consistent with the safety profile for nonprescription paracetamol and paracetamol/caffeine.