Purpose: The purpose of this study was to investigate the impact of low back pain (LBP) on future health-related quality of life (HRQoL). Current evidence suggests that individuals with LBP have poorer HRQoL than those without LBP. However, most of the evidence comes from cross-sectional studies where LBP and HRQoL are determined at the same time. One prospective study examined the association between days with LBP and HRQoL but did not account for the intensity of LBP. Therefore, this association needs to be tested in a large prospective population-based sample with a valid measure of LBP and adequate control of known confounders.
Methods: We formed a cohort of 1,110 randomly sampled Saskatchewan adults in September 1995. LBP at baseline was measured with the chronic pain questionnaire. The SF-36 questionnaire was used to measure physical and mental HRQoL at 6 months follow-up. Multivariable linear regression was used to estimate the association between graded LBP at baseline and HRQoL at 6 months while controlling for the effects of confounding.
Results: The 6-month follow-up rate was 70.7 % (785/1,110). LBP had a dose-response relationship with worsening physical HRQoL at 6 months, after controlling for age, income, arthritis, neck pain, and kidney disorders: grade III-IV LBP (β = -10.23; 95 % CI -12.46, -7.99), grade II LBP (β = -6.72, 95 % CI -8.79, -4.65), and grade I LBP (β = -1.77; 95 % CI -3.18, -0.36). There was no dose-response relationship between LBP and mental HRQoL at 6 months.
Conclusions: Low back pain has an impact on future physical HRQoL. Strategies for reducing the effects of LBP on HRQoL should be an important focus for clinicians, researchers, and health policy makers.