Does injury claim status and benefit status predict low back pain outcomes?

BACKGROUND: In New Zealand the Accident Compensation Corporation (ACC) is a state-funded insurance agency that accepts claims for accidental injuries, including lumbar spine injuries. It is unknown whether ACC claim status (accepted, not accepted) affects low back pain (LBP) outcomes, or whether benefit status (e.g., sickness, disability) further affects outcomes in patients without ACC cover. AIMS: This study aimed to determine whether ACC claim and benefit status are likely to influence a range of outcomes for people with LBP in New Zealand.
METHODS: A prospective survey of low back pain patients was performed (April 2008-October 2010). ACC claim status was recorded, and individuals without accepted claims indicated benefit status. Surveys were sent at multiple time points; pain, functional limitation, psychological factors, and general health were assessed. Statistical analysis was undertaken using ANCOVA and ANOVA (p<0.05).
RESULTS: In total, 168 patients completed the study. Six-month measures showed individuals with no ACC claim for LBP to overall have poorer outcomes (mental health, p=0.039; pain, p=0.045; functional limitation, p=0.049); sub-group analysis (no ACC claim) between those with or without a benefit showed those on benefits to have significantly higher functional limitation (p<0.001), poorer physical health (p=0.002), greater pain (p=0.027), and stronger fear avoidance behaviours for both work (p=0.047) and physical activity (p=0.35).
CONCLUSION: Findings indicate individuals with accepted ACC claims for LBP have significantly better outcomes than those without, and patients on benefits with no accepted ACC claim for LBP have even poorer outcomes.