AUTHOR=Peterson Jessica A. , Crow Joshua A. , Johnson Alisa J. , Meng Lingsong , Rani Asha , Huo Zhiguang , Foster Thomas C. , Fillingim Roger B. , Cruz-Almeida Yenisel 

TITLE=Pain interference mediates the association between epigenetic aging and grip strength in middle to older aged males and females with chronic pain

JOURNAL=Frontiers in Aging Neuroscience

VOLUME=Volume 15 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/aging-neuroscience/articles/10.3389/fnagi.2023.1122364

DOI=10.3389/fnagi.2023.1122364

ISSN=1663-4365

ABSTRACT=Objective: To explore the associations among self-reported pain, grip strength, and epigenetic aging in those with chronic pain. 
Methods: Participants (57.91 ± 8.04 years) with chronic pain completed pain questionnaires, a blood draw and handgrip task.  An epigenetic clock associated with knee pain (DNAmGrimAge) was used, and the subsequent difference of epigenetic age from chronological age (DNAmGrimAge-Difference) was calculated. 
Results: Exploratory pathway analyses (moderated-mediation) revealed that pain intensity mediated the association between DNAmGrimAge-difference and grip strength in males only (β =-0.1115; CI [-0.2929, -0.0008]) and pain interference mediated the association between DNAmGrimAge-difference and grip strength in males (β =-0.1401; CI [-0.3400, -0.0222]), and females (β =-0.024; CI [-0.2918, -0.0020]). 
Conclusions: Chronic pain may accelerate epigenetic aging processes that then may ultimately influence grip strength in older age males and females. Chronic pain could be a symptom of the aging body thus contributing to declines in musculoskeletal function in later life.