Bronchial Hyperresponsiveness to Methacholine Is Associated With Increased Common Carotid Intima-Media Thickness in Men

Abstract

Background— Respiratory alterations have been associated with subsequent coronary heart diseases in numerous population-based studies. The underlying mechanisms remain largely unknown. The objective of this study was to examine the association between bronchial hyperresponsiveness (BHR) to methacholine (which reflects local inflammation in the bronchus) and common carotid intima-media thickness (CCA-IMT). Methods and Results— As part of the European Community Respiratory Health Survey follow-up, in Paris Center, we assessed BHR to methacholine (≥20% decrease in FEV1 for a maximum methacholine dose of 4 mg) and measured CCA-IMT by ultrasonography in 255 adults free of cardiovascular diseases aged 29 to 56 years (123 men, 132 women; mean age 44.5 years, 43.5% never smokers). In men, CCA-IMT mean value was higher in subjects with BHR than in those without (0.68±0.11 versus 0.62±0.09 mm, P =0.002). No association was found in women. Multivariate analysis confirmed the independent association between BHR and CCA-IMT in men (adjusted odds ratio for a 0.10-mm increase in CCA-IMT=2.1, 95% confidence interval: 1.1 to 4.3; P =0.02). These results remained similar after exclusion of asthmatic subjects (n=11). In each strata of smoking status (nonsmoker, ex-smoker, and current smokers), CCA-IMT mean values tended to be higher in subjects with BHR than in those without, although the difference between the 2 groups was more pronounced in current smokers. Conclusions— The results of the present study suggest that BHR is independently associated with CCA-IMT in men. The interrelationships between cardiovascular and respiratory alterations should be further investigated.