Predicting the development of chronic low back pain (LBP) at the time of an acute episode remains challenging. The Understanding persistent Pain Where it ResiDes (UPWaRD) study aimed to identify neurobiological and psychological risk factors for chronic LBP. Individuals with acute LBP (N=120) participated in a prospective cohort study with six-month follow-up. Candidate predictors were selected from the neurobiological (e.g. sensorimotor cortical excitability assessed by sensory and motor evoked potentials, Brain Derived Neurotrophic Factor genotype), psychological (e.g. depression and anxiety), symptom-related (e.g. LBP history) and demographic domains. Analyses involved multivariable linear regression models with pain intensity or disability degree as continuous variables. Secondary analyses involved a multivariable logistic model with presence of low back pain at six months (thresholding pain intensity and disability degree) as a dichotomous variable. Lower sensory cortex and corticomotor excitability, higher baseline pain intensity, higher depression, stress and pain catastrophizing were the strongest predictors (R2=0.47) of pain intensity at six months. Older age and higher pain catastrophizing were the strongest predictors (R2=0.30) of disability at six months. When LBP outcome was dichotomised, sensory cortex and corticomotor excitability, BDNF genotype, depression and anxiety, LBP history and baseline pain intensity, accurately discriminated those who did and did not report LBP at six months (c-statistic 0.91). This study identifies novel risk factors for future LBP after an acute episode that can predict an individuals pain intensity and level of disability at six-month follow-up, and accurately discriminate between those who will and will not report LBP at six months.
Effect of a Simple Information Booklet on Pain Persistence after an Acute Episode of Low Back Pain: A Non-Randomized Trial in a Primary Care Setting