• Yen Tzu Chen and Susan Lynn Murphy.
• Department of Physical Medicine and Rehabilitation, University of Michigan, Ann Arbor, Michigan.
• Pain Med. 2021 Nov 26; 22 (11): 2575-2583.

ObjectiveTo examine associations of combined pain and fatigue severity with physical performance and quality of life in people with chronic knee pain.DesignCross-sectional.SettingGeneral community.ParticipantsAdults (N = 193) ≥50 years of age with chronic knee pain.MethodsPhysical performance measures included the Six-Minute Walk test, Timed Up and Go test, and 20-foot timed walk test. Quality of life (QOL) was measured by the Medical Outcomes Study Short Form-12 Health Survey. The Brief Pain Inventory (BPI) and Brief Fatigue Inventory (BFI) were used to evaluate pain and fatigue. Multiple linear regression analyses were conducted to examine associations of coexisting pain and fatigue severity with physical performance and QOL.ResultsParticipants were categorized by BPI and BFI scores into four severity groups: mild pain / mild fatigue; moderate pain / mild fatigue; mild pain / moderate fatigue; and moderate pain / moderate fatigue (which included severe pain / severe fatigue). The moderate pain / moderate fatigue group had significantly worse physical performance on the Six-Minute Walk (standardized beta [β] = -0.22, 95% confidence interval [CI] -0.38 to -0.06, P < 0.05) and poorer physical (β = -0.41, 95% CI -0.61 to -0.20, P < 0.001) and mental QOL (β = -0.26, 95% CI -0.46 to -0.07, P < 0.05) than the mild pain / mild fatigue group. Moreover, the mild pain / moderate fatigue group had significantly lower levels of mental QOL (β = -0.27, 95% CI -0.44 to -0.10, P < 0.05) than those of the mild pain / mild fatigue group. The moderate pain / mild fatigue group did not differ statistically from the mild pain / mild fatigue group.ConclusionsCoexisting moderate pain and moderate fatigue were related to worse physical performance and QOL. Fatigue contributed to lower levels of mental QOL. Clinical assessment of fatigue in addition to pain should be included as a standard examination for chronic knee pain.© The Author(s) 2021. Published by Oxford University Press on behalf of the American Academy of Pain Medicine.All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

16 keywords...

hide…