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

To evaluate and compare ratio and allometric scaling models of maximal oxygen consumption (VO₂max) for different body size measurements in relation to cardiovascular disease (CVD) incidence and all-cause mortality.

316 116 individuals participating in occupational health screenings, initially free from CVD, were included. VO₂max 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.

Increasing deciles of VO₂max 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·(kg¹·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.

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.