Causal relationship between leisure sedentary behaviors and low back pain risk: a Mendelian randomization study

This study aims to assess the causal associations of leisure sedentary behaviors with low back pain (LBP).

A Mendelian randomization (MR) study was carried out utilizing genetic instruments to determine whether leisure sedentary behaviors (including leisure television watching, leisure computer use, and driving) are causally associated with LBP. All instrumental variables were selected from publicly available genetic summary data. The inverse variance weighted (IVW) was used as the main method to conduct univariable MR analyses. Further sensitivity analyses were utilized to test the stability of the results. Moreover, multivariable MR was performed to evaluate the independent causal relationship between leisure sedentary behaviors and LBP when body mass index (BMI), waist circumference, smoking initiation, and vigorous physical activity were taken into account.

The MR analyses showed evidence that television watching increased the risk for LBP (OR: 1.97, 95% CI 1.45, 2.66; P = 1.19 × 10^-5). Genetically determined computer use is causally associated with a decreased risk of LBP (OR: 0.53, 95% CI 0.41, 0.68; P = 4.79 × 10^-7). However, no evidence was found of a causal relationship between driving and LBP (OR: 2.27, 95% CI 0.75, 6.81; P = 0.145). After adjusting for BMI, waist circumference, smoking initiation, and vigorous physical activity, only television maintained its causal effect on LBP.

This study indicated that genetically predicted television watching was a risk factor for LBP independent of BMI, waist circumference, smoking initiation, and vigorous physical activity. This finding may be helpful for the diagnosis and management of LBP.