Scaling VO2max to body size differences to evaluate associations to CVD incidence and all-cause mortality risk

Objective To evaluate and compare ratio and allometric scaling models of maximal oxygen consumption (VO(2)max) for different body size measurements in relation to cardiovascular disease (CVD) incidence and all-cause mortality. Methods 316 116 individuals participating in occupational health screenings, initially free from CVD, were included. VO(2)max was estimated using submaximal cycle test. Height, body mass and waist circumference (WC) were assessed, and eight different scaling models (two evaluated in a restricted sample with WC data) were derived. Participants were followed in national registers for first-time CVD event or all-cause mortality from their health screening to first CVD event, death or 31 December 2015. Results Increasing deciles of VO(2)max showed lower CVD risk and all-cause mortality for all six models in the full sample (p<0.001) as well as with increasing quintiles in the restricted sample (eight models) (p<0.001). For CVD risk and all-cause mortality, significantly weaker associations with increasing deciles for models 1 (L.min(-1)) and 5 (mL.min(-1).height(-2)) were seen compared with model 2 (mL.min(-1).kg(-1)), (CVD, p<0.00001; p<0.00001: all-cause mortality, p=0.008; p=0.001) and in some subgroups. For CVD, model 6 (mL.min(-1).(kg(1).height(-1))(-1)) had a stronger association compared with model 2 (p<0.00001) and in some subgroups. In the restricted sample, trends for significantly stronger associations for models including WC compared with model 2 were seen in women for both CVD and all-cause mortality, and those under 50 for CVD. Conclusion In association to CVD and all-cause mortality, only small differences were found between ratio scaling and allometric scaling models where body dimensions were added, with some stronger associations when adding WC in the models.