Relationship between cardiorespiratory fitness and non-high-density lipoprotein cholesterol: A cohort study

Aim: Recent studies have suggested that non-high-density lipoprotein cholesterol (non-HDL-C) may be a good marker of coronary heart disease and cardiovascular disease risk. Therefore, we investigated the relationship between cardiorespiratory fitness (CRF) and non-HDL-C.Methods: We evaluated CRF and the incidence of high level of non-HDL-C in 4,067 Japanese men without dyslipidemia. The participants were given a submaximal exercise test, a medical examination, and questionnaires on their health habits in 1986. A cycle ergometer was used to measure the CRF and maximal oxygen uptake was estimated. The incidence of a high level of non-HDL-C (≥170 mg/dL) from 1986 to 2006 was ascertained based on the fasting blood levels. A high level of non-HDL-C was found in 1,482 participants during the follow-up. Cox proportional hazard models were used to obtain the hazard ratios (HRs) and 95% confidence intervals (CIs) for the incidence of a high level of non-HDL-C.Results: Following age adjustment, and using the lowest CRF group (quartileⅠ) as reference, the HRs and 95% CIs for quartiles Ⅱ through Ⅳ were: 1.00 (95% CI: 0.87 –1.15), 0.87 (95% CI: 0.76 –1.00), and 0.70 (95% CI: 0.60 – 0.81), respectively (P for trend_＜0.001). After additional adjustment for body mass index, systolic blood pressure, smoking, alcohol intake, and family history of dyslipidemia, the HRs and 95% CIs were: 1.05 (95% CI: 0.92–1.21), 0.94 (95% CI: 0.81–1.08), and 0.79 (95% CI: 0.67–0.92), respectively (P for trend=0.001).Conclusions: These results suggest that there is an inverse relationship between CRF levels and the incidence of a high level of non-HDL-C in Japanese men.