Background Physical activity has been proposed as a modifiable risk factor for a number of cancers but few observational studies have investigated its effect on oesophageal and gastric carcinoma according to anatomical and histological subsite.
Aim This prospective cohort study aims to analyse the association between physical activity and risk of oesophageal or gastric adenocarcinoma.
Method A cohort of 3 59 425 adults aged 40-69 years (2006-2010) were identified from the UK biobank who completed a self-report International Physical Activity Questionnaire (IPAQ). Of this cohort, 295 incident oesophageal and 218 gastric cancer cases were identified. Adjusted HRs and 95% CIs for the associations between hours per week from physical activity and categories of physical activity based on IPAQ guidelines (Low, medium and high) and risk of oesophageal cancer and gastric cancer were calculated.
Results When compared with low physical activity, high activity was not associated with oesophago-gastric cancer risk. However moderate level physical activity was associated with a reduction in risk of oesophageal adenocarcinoma by 35% after adjustment for confounders (adjusted HR=0.65, 95% CI 0.45 to 0.95). This held for moderate vs low physical activity and any oesophago-gatric adenocarcinoma (adjusted HR=0.70, 95% CI 0.53 to 0.92). This protective effect was not observed for oesophageal squamous cell carcinoma or total gastric cancer risk across physical activity categories.
Conclusions In this large prospective cohort, high physical activity levels were not associated with overall risk of oesophago-gastric cancer. However, moderate physical activity was associated with a reduced risk of oesophageal adenocarcinoma tumours.