Ventilatory function and cardiovascular disease risk factors: a cross-sectional study in young adults

BACKGROUND: The association between impaired lung function and cardiovascular disease (CVD) risk factors has been shown in adults. However, there is little evidence of such an association in young adults, particularly from South America, where the burden of CVD and chronic obstructive pulmonary disease (COPD) is as high as that observed in more developed countries. We therefore investigated the relation between CVD risk factors including metabolic syndrome (MS), and lung function status in young adults from Chile. METHODS: 970 subjects from a sample of 998 adults born between 1974 and 1978 in Limache, Chile, were studied. A Spanish translation of the European Community Respiratory Health Survey (ECRHS) questionnaire was used. Forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) were measured. Weight, height, waist circumference (WC), blood pressure, Homeostatic model assessment (HOMA-IR), triglycerides, high density lipoprotein (HDL), glycaemia, and metabolic syndrome (MS) were also assessed. RESULTS: The prevalence of MS was 11.8%. A lower FEV(1) and lower FVC were associated with having MS (β-coefficient -0.13; 95% Confidence Interval [CI] -0.21 to -0.05, and β-coefficient -0.18; 95% CI -0.27 to -0.09, respectively). Both spirometric measures were also negatively associated with having an elevated HOMA-IR (β-coefficient for FEV(1) -0.08; 95% CI -0.13 to -0.03, and β-coefficient for FVC -0.11; 95% CI -0.17 to -0.05). In males only, a lower FEV(1) and FVC were associated with having elevated triglycerides (β-coefficient highest vs. lowest tertile -0.13, 95% CI -0.24 to -0.03, and β-coefficient -0.13, 95% CI -0.25 to -0.01, respectively). In women, a higher FEV(1) and FVC were statistically significantly related to having higher levels of HDL. Ventilatory function was unrelated to hypertension or WC in this population. CONCLUSION: In this population-based study of young adults, a poorer ventilatory function was associated with many CVD risk factors. Endeavours to understand better causality issues of such associations are warranted.