Genetic loci associated with certain sedentary leisure activities are reported in Nature Communications this week. Based on genetic and observational analyses, the paper suggests that spending an increased amount of time watching television may be a risk factor for coronary artery disease (CAD).
To understand how genetics may affect sedentary behaviour and to investigate whether sedentary behaviours are a potential causal risk factor for CAD, Niek Verweij and colleagues performed a genome wide association study. Using data from 422,218 individuals (aged between 40 and 69) of European ancestry from the UK Biobank, the authors identified 169 genetic loci associated with sedentary leisure activities (145 associated with watching television, 36 with computer use and 4 with driving, with 16 loci overlapping between two of the sedentary traits). In a Mendelian randomization analysis, they estimated that a 1.5 hour increase in the daily amount of television watching (above an average of 2.8 hours) is an increased risk factor for CAD. However, an association between computer use or driving and CAD was not established.
The authors caution that information about sedentary behaviour was subjectively measured by individuals in the cohort and did not include sedentary behaviours associated with their occupation. They note that further research is required to expand the analysis to include total sedentary behaviour, physical activity and sleep behaviours.