Systemic inflammation, sleep and psychological factors determine recovery trajectories for people with neck pain. An exploratory study.

We conducted an explorative prospective cohort study with six months follow-up to (1) identify different pain and disability trajectories following an episode of acute neck pain, and (2) assess whether neuroimmune/endocrine, psychological, behavioural, nociceptive processing, clinical outcome, demographic and management-related factors differ between these trajectories. Fifty people with acute neck pain (i.e., within two weeks of onset) were included. At baseline, and at two, four, six, 12 and 26 weeks follow-up, various neuroimmune/endocrine (e.g., inflammatory cytokines and endocrine factors), psychological (e.g., stress symptoms), behavioural (e.g., sleep disturbances), nociceptive processing (e.g., condition pain modulation), clinical outcome (e.g., trauma), demographic factors (e.g., age) and management-related factors (e.g., treatment received) were assessed. Latent class models were performed to identify outcome trajectories for neck pain and disability. Linear mixed models or the Pearson chi-square test were used to evaluate differences in these factors between the trajectories at baseline and at each follow-up assessment and over the entire six months period. For pain, three trajectories were identified. The majority of patients were assigned to the 'Moderate pain - Favourable recovery' trajectory (n=25; 50%) with smaller proportions assigned to the 'Severe pain - Favourable recovery' (n=16; 32%) and the 'Severe pain - Unfavourable recovery' (n=9; 18%) trajectories. For disability, two trajectories were identified: 'Mild disability - Favourable recovery' (n=43; 82%) and 'Severe disability - Unfavourable recovery' (n=7; 18%). Ongoing systemic inflammation (increased hsCRP), sleep disturbances and elevated psychological factors (such as depression, stress and anxiety symptoms) were mainly present in the unfavourable outcome trajectories compared to the favourable outcome trajectories. PERSPECTIVE: Using exploratory analyses, different recovery trajectories for acute neck pain were identified based on disability and pain intensity. These trajectories were influenced by systemic inflammation, sleep disturbances, and psychological factors.