Impact of cardiorespiratory fitness and diabetes status on cardiovascular disease and all-cause mortality: An NHANES retrospective cohort study

Gwendolyn A Ung; Kevin H Nguyen; Alvin Hui; Nathan D Wong; Elizabeth H Dineen

doi:10.1016/j.ahjo.2024.100395

Impact of cardiorespiratory fitness and diabetes status on cardiovascular disease and all-cause mortality: An NHANES retrospective cohort study

Am Heart J Plus. 2024 Apr 17:42:100395. doi: 10.1016/j.ahjo.2024.100395. eCollection 2024 Jun.

Authors

Gwendolyn A Ung¹, Kevin H Nguyen¹, Alvin Hui¹, Nathan D Wong², Elizabeth H Dineen³

Affiliations

¹ Western University of Health Sciences College of Osteopathic Medicine of the Pacific-Pomona, CA, United States of America.
² Division of Cardiology, University of California, Irvine School of Medicine, Irvine, CA, United States of America.
³ Department of Cardiovascular Diseases, Mayo Clinic, Jacksonville, FL, United States of America.

Abstract

High cardiorespiratory fitness (CRF) is associated with decreased mortality in people with pre-diabetes (pre-DM) and diabetes mellitus (DM); however, the degree to which CRF attenuates the risk of cardiovascular disease (CVD)-related and all-cause mortality is unclear.

Study objective: We examined the impact of CRF status on CVD-related morbidity and all-cause mortality in non-DM, Pre-DM, and DM populations.

Design and setting: 13,968 adults from the Third US National Health and Nutrition Examination Survey (NHANES III) were stratified into non-DM, pre-DM, or DM groups based on HbA1c levels. VO₂Max was calculated using the Fitness Registry and Importance of Exercise: A National Database (FRIEND) equation.

Participants: Participants were categorized into tertiles of VO₂Max; first VO₂Max tertile was the lowest VO₂Max and third VO₂Max tertile was the highest.

Main outcome measures: Cox regression was used to analyze the relationship between glycemic levels, VO₂Max, and CVD-related and all-cause mortality.

Results: Those with DM in the highest fitness tertile had CVD (HR 0.13; 95 % CI 0.06, 0.27; p < 0.0001) and all cause (HR 0.28; 95 % CI 0.21, 0.38; p < 0.0001) mortality rates as low or lower than those with pre-DM (CVD HR 1.02; 95 % CI 0.78, 1.33 p < 0.892; all cause HR 0.96; 95 % CI 0.83, 1.12; p < 0.5496) or non-DM (CVD HR 0.65; 95 % CI 0.52, 0.80; p < 0.0001; all cause HR 0.61; 95 % CI 0.55, 0.68; p < 0.0001) at lower fitness levels. Regardless of DM status, there was lower all-cause mortality with higher CRF levels.

Conclusions: Higher fitness levels in DM individuals are associated with total and CVD mortality rates as low or lower than those without DM with lower fitness.

Keywords: Cardiorespiratory fitness; Cardiovascular disease; Diabetes; Mortality.