Association between physical activity, sedentary behaviour and the trajectory of low back pain.

BACKGROUND: Low back pain (LBP) is one of the world's most prevalent health issues. Patients with LBP experience various intensities and durations of symptoms, which can lead to distinctive course patterns commonly described as symptom trajectories.

PURPOSE: This study aimed to investigate the association between different amounts of physical activity and sedentary behavior and the trajectory of LBP, in people with a lifetime history of LBP.

STUDY DESIGN: The study involved a secondary analysis of observational longitudinal data collected from the AUstralian Twin low BACK pain (AUTBACK) study.

METHODS: A total of 329 individual twins met the inclusion criteria for analysis. Latent Class Growth Analysis was used to identify distinct patterns of LBP and select the primary outcome (probability of having a severe LBP trajectory, 0%-100%). Linear regression models were used to investigate the association between different amounts of physical activity or sedentary behavior at baseline, and the probability of having a severe LBP trajectory. Results were expressed as β coefficients and 95% confidence intervals (CI).

RESULTS: Moderate-to-vigorous intensity physical activity was significantly associated with the probability of having a severe LBP trajectory (unadjusted β -0.0276; 95%CI -0.0456 to -0.0097, p=.003). For every 1-minute increase in moderate-to-vigorous intensity physical activity per week, there was a 2.8%-point reduction in a participant's probability of having a severe LBP trajectory. No significant associations were identified between sedentary behavior or light intensity physical activity, and the probability of having a severe LBP trajectory.

CONCLUSIONS: In people with a lifetime history of LBP, engagement in higher volumes of moderate to vigorous intensity physical activity at baseline was associated with a lower probability of developing a severe trajectory of LBP over 1 year.