Changes in fitness and fatness on the development of cardiovascular disease risk factors hypertension, metabolic syndrome, and hypercholesterolemia

Abstract

Objectives: This study sought examine the independent and combined associations of changes in fitness and fatness with the subsequent incidence of the cardiovascular disease (CVD) risk factors of hypertension, metabolic syndrome, and hypercholesterolemia.

Background: The relative and combined contributions of fitness and fatness to health are controversial, and few studies are available on the associations of changes in fitness and fatness with the development of CVD risk factors.

Methods: We followed up 3,148 healthy adults who received at least 3 medical examinations. Fitness was determined by using a maximal treadmill test. Fatness was expressed by percent body fat and body mass index. Changes in fitness and fatness between the first and second examinations were categorized into loss, stable, or gain groups.

Results: During the 6-year follow-up after the second examination, 752, 426, and 597 adults developed hypertension, metabolic syndrome, and hypercholesterolemia, respectively. Maintaining or improving fitness was associated with lower risk of developing each outcome, whereas increasing fatness was associated with higher risk of developing each outcome, after adjusting for possible confounders and fatness or fitness for each other (all p for trend <0.05). In the joint analyses, the increased risks associated with fat gain appeared to be attenuated, although not completely eliminated, when fitness was maintained or improved. In addition, the increased risks associated with fitness loss were also somewhat attenuated when fatness was reduced.

Conclusions: Both maintaining or improving fitness and preventing fat gain are important to reduce the risk of developing CVD risk factors in healthy adults.

Figure 1. Hazard Ratios (95% Confidence Intervals) of Incident Cardiovascular Disease Risk Factors by Combined Categories of Changes in Cardiorespiratory Fitness and Percent Body Fat

Adjusted for age, sex, examination year, maximal METs, % body fat at baseline, and baseline systolic blood pressure for hypertension, baseline metabolic syndrome components (systolic blood pressure, fasting glucose, triglyceride, HDL cholesterol, and waist circumference) for metabolic syndrome, or baseline total cholesterol for hypercholesterolemia, and lifestyle changes (smoking status, alcohol intake, and physical activity) between the baseline and second examinations. The number of participants in the fitness loss, stable, and gain groups were 130, 401, and 520 in the % body fat loss group; 305, 488, and 255 in the stable % body fat group; and 350, 444, and 255 in the % body fat gain group, respectively. HR = hazard ratio; CI = confidence interval.