| Objective: To examine the separate roles that pain severity and pain-related interference play in moderating dual-task performance costs on primary gait and secondary cognitive interference tasks in a walking while talking dual-task in community-dwelling older adults. Participants and Methods: A cross-sectional sample of 330 non-demented community-dwellers (age 65 -- 95 years, 56% females) completed a self-report measure, the Pain Scale in the Medical Outcomes Study Functioning and Well-Being Profile. Participants' gait speed was calculated for normal walk (NW) and walking while talking (WWT) on an instrumented walkway. Cognitive performance was measured by percent accuracy in a serial 7's subtraction task in both tasks in single and WWT conditions. Results: Of the 64% of older adults who reported mild to severe pain in the past month, 77% reported pain-interference in at least one aspect of their social, emotional, and/or physical functioning. Participants with pain interference had significantly reduced gait speed in NW compared to participants experiencing pain without interference and participants without pain, [F(2,330) = 4.49,p = .012]. An adjusted linear mixed effects model revealed participants with pain interference demonstrated less dual-task cost in velocity compared to those without pain, (beta = -5.38; 95% CI= -10.45 to -0.22,p = .041). Participants with severe pain had significantly reduced gait speed in NW compared to older adults without pain and mild pain, F(3,330) = 5.6.0, p = .001]. When comparing older adults with severe pain directly to those without pain, a significant moderating effect on gait speed was also observed, (beta = -8.83; 95% CI= -17.58 to - .0.09, p < .05). Conclusion: Results suggest that a cognitively demanding interference task (e.g., serial 7 subtractions) may disrupt processing of pain signals that typically interfere with gait when assessed under single task conditions. Pain interference and severity resulted in reduced dual-task costs in gait speed. Cognitive interference tasks might be used as a distraction to facilitate more efficient locomotion in older adults with pain under attention demanding conditions. |
