Central sensitization and functioning in patients with chronic low back pain: A cross-sectional and longitudinal study

J Back Musculoskelet Rehabil. 2022;35(6):1179-1190. doi: 10.3233/BMR-210322.

Abstract

Background: Central sensitization (CS) is present in a subgroup of patients with chronic low back pain (CLBP). Studies on the relationship between CS and functioning have limited operationalizations of CS and functioning.

Objective: To determine whether CS was related to functioning in patients with CLBP (cross-sectional); and to determine whether changes in CS were related to changes in functioning (longitudinal).

Methods: An observational prospective cohort study with data collected at baseline and discharge of an interdisciplinary pain rehabilitation program was executed. CS indicators: CS Inventory part A (CSI-A), quantitative sensory testing (QST), root mean square of successive differences of heart-rate variability (RMSSD). Functioning measures: lifting capacity, physical functioning subscale of Rand36 (Rand36-PF), Work Ability Score (WAS), Pain Disability Index (PDI). Main analyses included correlation and multiple regression controlling for confounders; cross-sectional with baseline data and longitudinal with deltas (ฮ”).

Results: 76 patients with primary CLBP participated at baseline and 56 at discharge. Most associations were weak (cross-sectional r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™=-0.30-0.24; longitudinal r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™=-0.37-0.44). Cross-sectional multiple regression significant associations: mechanical pain threshold-QST and lifting capacity (r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™=-0.39), parasympathetic/vagal tone-RMSSD and physical functioning-Rand36-PF (r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™= 0.26). Longitudinal multiple regression significant associations: ฮ” parasympathetic/vagal tone-RMSSD and ฮ” lifting capacity (r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™= 0.48), ฮ”CSI-A and ฮ”disability-PDI (r๐‘๐‘Ž๐‘Ÿ๐‘ก๐‘–๐‘Ž๐‘™= 0.36). Cross-sectional and longitudinal final regression models explained 24.0%-58.3% and 13.3%-38.0% of total variance.

Conclusion: CS was weakly related to functioning, and decreases in CS were weakly-moderately related to increases in functioning.

Keywords: Hyperalgesia; disability; lifting; physical functioning; work ability.

Publication types

  • Observational Study

MeSH terms

  • Central Nervous System Sensitization
  • Chronic Pain*
  • Cross-Sectional Studies
  • Humans
  • Longitudinal Studies
  • Low Back Pain*
  • Prospective Studies
  • Surveys and Questionnaires