Sedentary Leisure Behaviour, Physical Activity, and Gastroesophageal Reflux Disease: Evidence From a Mendelian Randomization Analysis.

BACKGROUND AND AIMS

Gastroesophageal reflux disease (GERD) is common worldwide. Although associations between sedentary behaviour (LSBs), physical activity (PAs), and GERD have been reported, their causal relationships remain unclear. This study uses Mendelian randomization (MR) to examine these associations with GERD.

METHODS

Genetic instruments from the UK Biobank and other consortia were utilized to assess the causal relationship between LSBs, PAs, and GERD. Causal analyses employed inverse variance weighted (IVW), weighted-median (WM), and MR-Egger regression. Sensitivity analyses included Cochran's test, MR-Egger intercept test, leave-one-out analysis, and funnel plot assessment. Outliers were detected using MR-PRESSO and Radial MR. A risk factor analysis explored potential causal links.

RESULTS

Genetically predicted leisure television (TV) watching (OR = 2.29, 95% CI 2.12-2.48;  < 0.001) and self-reported moderate physical activity (MPAs) (OR = 2.45, 95% CI 1.46-4.13;  < 0.001) were associated with an higher risk of GERD. In contrast, leisure computer use (OR = 0.62, 95% CI 0.53-0.73;  < 0.001) and accelerometer-measured fractional accelerations > 425 milligravities (OR = 0.68, 95% CI 0.52-0.88;  = 0.003) were associated with a lower risk of GERD. No causal relationship was observed between driving, self-reported vigorous physical activities (VPAs), and accelerometer-measured "average acceleration" with GERD. Risk factor analyses suggested that metabolic risk factors, such as smoking, high body mass index, elevated serum triglyceride levels, insulin resistance, and type 2 diabetes might mediate the observed causal links.

CONCLUSIONS

Leisure TV watching and self-reported MPA are associated with an higher risk of GERD, whereas leisure computer use and accelerometer-measured fractional acceleration > 425 milligravities may serve as protective factors against GERD. These findings highlight the necessity of differentiating various LSBs and PAs in GERD research.