Association Between Cardiorespiratory Fitness and Indices of Coronary Artery Calcification in Men

Separate and Joint Associations of Cardiorespiratory Fitness and Healthy Vascular Aging With Subclinical Atherosclerosis in Men

BACKGROUND

Achieving healthy vascular aging (HVA) is important for decelerating age-related cardiovascular disease risk. We evaluated the interplay between HVA, cardiorespiratory fitness (CRF), and subclinical atherosclerosis.

METHODS

We analyzed data on 3722 men who underwent cardiopulmonary exercise testing in a health examination program. HVA was defined as blood pressure <140/90 mm Hg without hypertension and brachial-ankle pulse wave velocity <1266 cm/s. CRF was directly measured by peak oxygen uptake. Subclinical atherosclerosis was defined as coronary artery calcification scores of >0 and ≥100 and a mean carotid artery intima-media thickness (CIMT) >75th percentile for each age group as well as >0.8 mm of CIMT. Separate and joint associations of HVA and CRF with subclinical atherosclerosis were evaluated.

RESULTS

Each 1 metabolic equivalent increment in CRF was associated with 23% higher odds for having HVA. HVA was associated with lower odds of coronary artery calcification but not CIMT. CRF modified the association between HVA and CIMT>0.8 mm (interaction: P=0.01); HVA was associated with lower odds of CIMT>0.8 mm in fit men with no significant association between HVA and CIMT>0.8 mm in unfit men. Compared with no HVA and being unfit, HVA and being fit was associated with lower odds of subclinical atherosclerosis, but there was no significant association between HVA and being unfit with subclinical atherosclerosis.

CONCLUSIONS

HVA and higher CRF are each associated with a lower risk of subclinical atherosclerosis in men. Higher CRF is associated with a higher prevalence of HVA and may modify the association between HVA and subclinical atherosclerosis.

Association of Estimated Cardiorespiratory Fitness in Midlife With Cardiometabolic Outcomes and Mortality

IMPORTANCE

The associations of estimated cardiorespiratory fitness (eCRF) during midlife with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality are not well understood.

OBJECTIVE

To examine associations of midlife eCRF with subclinical atherosclerosis, arterial stiffness, incident cardiometabolic disease, and mortality.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 2962 participants in the Framingham Study Second Generation (conducted between 1979 and 2001). Data were analyzed from January 2020 to June 2020.

EXPOSURES

eCRF was calculated using sex-specific algorithms (including age, body mass index, waist circumference, physical activity, resting heart rate, and smoking) and was categorized as: (1) tertiles of standardized eCRF at examination cycle 7 (1998 to 2001); (2) tertiles of standardized average eCRF between examination cycles 2 and 7 (1979 to 2001); and (3) eCRF trajectories between examination cycles 2 and 7, with the lowest tertile or trajectory (ie, low eCRF) as referent group.

MAIN OUTCOMES AND MEASURES

Subclinical atherosclerosis (carotid intima-media thickness [CIMT], coronary artery calcium [CAC] score); arterial stiffness (carotid-femoral pulse wave velocity [-1000/CFPWV]); incident hypertension, diabetes, chronic kidney disease (CKD), cardiovascular disease (CVD), and mortality after examination cycle 7.

RESULTS

A total of 2962 participants were included in this cohort study (mean [SD] age, 61.5 [9.2] years; 1562 [52.7%] women). The number of events or participants at risk after examination cycle 7 (at a mean follow-up of 15 years) was 728 of 1506 for hypertension, 214 of 2268 for diabetes, 439 of 2343 for CKD, 500 of 2608 for CVD, and 770 of 2962 for mortality. Compared with the low eCRF reference value, high single examination eCRF was associated with lower CFPWV (β [SE], -11.13 [1.33] ms/m) and CIMT (β [SE], -0.12 [0.05] mm), and lower risk of hypertension (hazard ratio [HR], 0.63; 95% CI, 0.46-0.85), diabetes (HR, 0.38; 95% CI, 0.23-0.62), and CVD (HR, 0.71; 95% CI, 0.53-0.95), although it was not associated with CKD or mortality. Similarly, compared with the low eCRF reference, high eCRF trajectories and mean eCRF were associated with lower CFPWV (β [SE], -11.85 [1.89] ms/m and -10.36 [1.54] ms/m), CIMT (β [SE], -0.19 [0.06] mm and -0.15 [0.05] mm), CAC scores (β [SE], -0.67 [0.25] AU and -0.63 [0.20] AU), and lower risk of hypertension (HR, 0.54; 95% CI, 0.34-0.87 and HR, 0.48; 95% CI, 0.34-0.68), diabetes (HR, 0.27; 95% CI, 0.15-0.48 and HR, 0.31; 95% CI, 0.18-0.54), CKD (HR, 0.63; 95% CI, 0.40-0.97 and HR, 0.64; 95% CI, 0.44-0.94), and CVD (HR, 0.46; 95% CI, 0.31-0.68 and HR, 0.43; 95% CI, 0.30-0.60). Compared with the reference value, a high eCRF trajectory was associated with lower risk of mortality (HR, 0.69; 95% CI, 0.50-0.95).

CONCLUSIONS AND RELEVANCE

In this cohort study, higher midlife eCRF was associated with lower burdens of subclinical atherosclerosis and vascular stiffness, and with a lower risk of hypertension, diabetes, chronic kidney disease, cardiovascular disease, and mortality. These findings suggest that midlife eCRF may serve as a prognostic marker for subclinical atherosclerosis, arterial stiffness, cardiometabolic health, and mortality in later life.