Because of its high global burden, determining biopsychosocial influences of chronic low back pain (CLBP) is a research priority. Psychological factors such as pain catastrophizing are well established. However, cognitive factors like working memory require further investigation to be clinically useful. The objective of this study was to determine how working memory and pain catastrophizing are associated with CLBP measures of daily pain intensity and movement-evoked pain intensity. A aross-sectional analysis of individuals with ≥3 months CLBP (n=60) compared to pain-free controls (n=30) was performed. Participants completed measures of working memory, pain catastrophizing and daily pain intensity. Movement-evoked pain intensity was assessed using the Back Performance Scale. Outcome measures were compared between individuals with CLBP and those pain-free using ANOVA modeling. Associations were determined using multivariate regression analyses. CLBP participants (mean age=47.7, 68% females) had lower working memory performance (p=.008) and higher pain catastrophizing (p<.001) compared to pain-free controls (mean age=47.6, 63% females). For CLBP individuals, only working memory remained associated with daily pain intensity (R2=.07, standardized Beta=-.308, p=.041) and movement-evoked pain intensity (R2=.14, standardized Beta=-.502, p=.001) after accounting for age, sex, education and interactions between pain catastrophizing and working memory.
Working memory demonstrated the strongest association with daily pain and movement-evoked pain intensity compared to and after accounting for established CLBP factors. Future research will elucidate the prognostic value of working memory on prevention and/or recovery of CLBP.