[Association between cardiorespiratory fitness and mortality risk in the chilean population]

Cardiorespiratory fitness reduces the risk of cardiometabolic diseases, cancer and mortality. The aim of this paper was to evaluate the relationship between equation-estimated cardiorespiratory fitness and all-cause mortality in the Chilean population of both genders according to data from the 2009-2010 National Health Survey (NHS).

Data from 4,749 participants from the 2009-2010 NHS were analysed after 10.9 years of follow-up. Fitness was estimated with the Myers et al. equation and classified into quintiles. All-cause mortality records were obtained from the Chilean Civil Registry and Identification until 2020. Cox regression models adjusted for confounding variables (demographics, nutritional status, lifestyle and comorbidities) were used to assess the association between fitness and mortality.

During the 10.9 years (IQR: 10.8; 11.4) of follow-up 506 (10.6%) people died. Compared to the lowest fitness quintile (<7 METs) those classified in the highest quintile (>12 METs) had a 95% lower risk of mortality (HR: 0.05; 95% CI: 0.03, 0.09) and the risk of mortality was 28% lower for every 1-METs increase in fitness (HR: 0.72 95% CI: 0.69, 0.75). All these associations were independent of confounders.

We conclude that a higher level of fitness is associated with a lower risk of mortality independent of confounding factors in the Chilean population after 10.9 years of follow-up.