Cardiorespiratory Fitness and the Progression of Carotid Atherosclerosis in Middle-Aged Men

Cardiorespiratory Fitness and the Progression of Carotid Atherosclerosis in Middle-Aged Men

Timo A. Lakka, MD, PhD;
Jari A. Laukkanen, MD;
Rainer Rauramaa, MD, PhD;
Riitta Salonen, MD, PhD;
Hanna-Maaria Lakka, MD;
George A. Kaplan, PhD; and
Jukka T. Salonen, MD, PhD, MScPH

From University of Kuopio, Kuopio Research Institute of Exercise Medicine, Research Institute of Public Health, and Kuopio University Hospital, Kuopio, Finland; and University of Michigan School of Public Health, Ann Arbor, Michigan.

Abstract

Background: Good cardiorespiratory fitness has been associated with reduced risk for clinical events of atherosclerotic vascular diseases, but whether it is related to slower progression of early atherosclerosis is unclear.

Objective: To study the association between cardiorespiratory fitness and the progression of early carotid atherosclerosis.

Design: 4-year follow-up study.

Setting: Eastern Finland.

Participants: Population-based sample of 854 men 42 to 60 years of age.

Measurements: Maximal oxygen uptake (VO₂ max [mL/kg per minute]) was measured directly by using respiratory gas exchange in a cycle ergometer exercise test. Carotid atherosclerosis was assessed by using B-mode ultrasonography.

Results: After adjustments for age, technical covariates, and cigarette smoking, VO₂ max had strong, inverse, and graded associations with 4-year increases in maximal intima–media thickness (IMT) (standardized regression coefficient β = −0.120; P = 0.002), plaque height (β = −0.140; P < 0.001), surface roughness (β = −0.147; P < 0.001), and mean IMT (β = −0.080; P = 0.035). These associations weakened but remained statistically significant after additional adjustment for systolic blood pressure, serum levels of apolipoprotein B, diabetes, and plasma fibrinogen levels. The increases in maximal IMT, surface roughness, and mean IMT (23%, 31%, and 100%, respectively) were larger among men in the lowest quartile of VO₂ max (<26.1 mL/kg per minute) than among those in the highest quartile (>36.2 mL/kg per minute).

Conclusions: Good cardiorespiratory fitness is associated with slower progression of early atherosclerosis in middle-aged men. These findings are important because they emphasize that middle-aged men can be evaluated for cardiorespiratory fitness to estimate their future risk for atherosclerotic vascular diseases. Additional research is warranted to investigate a possible causal relationship between cardiorespiratory fitness and atherosclerosis.

Article and Author Information

Acknowledgments: The authors thank Juha M. Venäläinen, Esko Taskinen, and Hannu Litmanen for their participation in the supervision of exercise tests and Kristiina Nyyssönen and Kari Seppänen for supervising laboratory measurements. They also thank the staff of the Research Institute of Public Health, University of Kuopio, Kuopio, Finland, and the Kuopio Research Institute of Exercise Medicine, Kuopio, Finland, for data collection in the KIHD.
Grant Support: By the Academy of Finland (41471, 1041086, and 2041022); the Finnish Ministry of Education (167/722/96, 157/722/97, and 156/722/98); and the U.S. National Heart, Lung, and Blood Institute (grant HL44199).
Requests for Single Reprints: Timo A. Lakka, MD, PhD, Research Institute of Public Health, University of Kuopio, Box 1627, FIN-70211 Kuopio, Finland; e-mail, timo.lakka{at}uku.fi.
Current Author Addresses: Drs. T.A. Lakka, Laukkanen, R. Salonen, H.-M. Lakka, and J.T. Salonen: Research Institute of Public Health, University of Kuopio, Box 1627, 70211 Kuopio, Finland.
Dr. Rauramaa: Kuopio Research Institute of Exercise Medicine, Haapaniementie 16, 70100 Kuopio, Finland.
Dr. Kaplan: Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor, MI 48109.
Author Contributions: Conception and design: T.A. Lakka, J.A. Laukkanen, R. Rauramaa, R. Salonen, G.A. Kaplan, J.T. Salonen.
Analysis and interpretation of the data: T.A. Lakka, J.A. Laukkanen, R. Rauramaa, H.-M. Lakka.
Drafting of the article: T.A. Lakka, J.A. Laukkanen, H.-M. Lakka, G.A. Kaplan.
Critical revision of the article for important intellectual content: T.A. Lakka, J.A. Laukkanen, R. Rauramaa, H.-M. Lakka, G.A. Kaplan, J.T. Salonen.
Final approval of the article: T.A. Lakka, J.A. Laukkanen, R. Rauramaa, R. Salonen, H.-M. Lakka, G.A. Kaplan, J.T. Salonen.
Provision of study materials or patients: T.A. Lakka, R. Salonen, G.A. Kaplan, J.T. Salonen.
Statistical expertise: T.A. Lakka, H.-M. Lakka, J.T. Salonen.
Obtaining of funding: T.A. Lakka, R. Rauramaa, G.A. Kaplan, J.T. Salonen.
Administrative, technical, or logistic support: T.A. Lakka, R. Salonen, J.T. Salonen.
Collection and assembly of data: T.A. Lakka, R. Salonen, J.T. Salonen.