Greater recalled pain and movement-evoked pain are associated with longer 400-meter walk and repeat stair climb time: the Study of Muscle, Mobility and Aging.

BACKGROUND

Musculoskeletal pain frequently accompanies the development of mobility disability and falls in old age. To better understand this, we aimed to quantify the impact of different pain measures-recalled pain and movement-evoked pain-on 400-meter walk and stair climb time in older adults participating in the Study of Muscle, Mobility and Aging (SOMMA).

METHODS

In SOMMA (N=879, age=76.3 ± 5.0 years, 59% women, 84% Non-Hispanic White), participants completed usual pace 400m walk (avg=6.6 ± 1.2 min.) and repeat stair climb tests (avg=26.6 ± 7.2 sec.). Assessments of recalled pain included the Brief Pain Inventory short form (BPI-sf), total lower body pain (lower back, hips, knees, feet/ankles), stiffness (hip or knee), and Neuropathy Total Symptom Score (NTSS-6). Movement-evoked pain was assessed separately before and after the 400m walk and repeat stair climb tasks. Multivariable linear regression modeled the associations of pain with time to complete the tasks, reported as β[95%CI] expressed per SD increment of pain measure or β[95%CI] per pain categories, adjusted for age, sex, race, ethnicity, body mass index, prescription medications, and depressive symptoms.

RESULTS

Greater degree of any pain measure was associated with longer physical performance time, though intercorrelations between recalled pain measures varied (r=0.13-0.57, p<0.05 for all). For each SD increment in lower body pain, participants had longer walk time (by 10.5 sec [6.1, 14.8]) and stair climb (by 0.6 sec [0.1, 1.1]). Compared to participants with no change in pain upon movement, walk time was longer in those with more pain upon movement (19.5 sec [10.3, 28.7]) (p<0.001) but not those with less pain upon movement; stair climb showed similar patterns.

CONCLUSIONS

Recalled and movement-evoked pain measures were weakly correlated with one another but similarly associated with time to complete 400m walk and stair climb tests. Different pain assessments capture different functional domains of pain but have similar associations with physical performance in these older adults.