Letter by Wang et al Regarding Article, “Childhood Air Pollutant Exposure and Carotid Artery Intima–Media Thickness in Young Adults”

Abstract

HomeCirculationVol. 127, No. 22Letter by Wang et al Regarding Article, “Childhood Air Pollutant Exposure and Carotid Artery Intima–Media Thickness in Young Adults” Free AccessResearch ArticlePDF/EPUBAboutView PDFView EPUBSections ToolsAdd to favoritesDownload citationsTrack citationsPermissions ShareShare onFacebookTwitterLinked InMendeleyReddit Jump toFree AccessResearch ArticlePDF/EPUBLetter by Wang et al Regarding Article, “Childhood Air Pollutant Exposure and Carotid Artery Intima–Media Thickness in Young Adults” Xi-Mei Wang, PhD, Yue-Jin Yang, MD, PhD and Yong-Jian Wu, MD, PhD Xi-Mei WangXi-Mei Wang Department of Cardiology, State Key Laboratory of Cardiovascular DiseaseFuwai Hospital, National Centre for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, People’s Republic of China Search for more papers by this author , Yue-Jin YangYue-Jin Yang Department of Cardiology, State Key Laboratory of Cardiovascular DiseaseFuwai Hospital, National Centre for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, People’s Republic of China Search for more papers by this author and Yong-Jian WuYong-Jian Wu Department of Cardiology, State Key Laboratory of Cardiovascular DiseaseFuwai Hospital, National Centre for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, People’s Republic of China Search for more papers by this author Originally published4 Jun 2013https://doi.org/10.1161/CIRCULATIONAHA.112.141564Circulation. 2013;127:e658To the Editor:We read with great interest the recently published article by Breton et al1 regarding childhood air pollutant exposure and carotid artery intima–media thickness (CIMT) in young adults. The authors report that childhood exposure to O3 is a novel risk factor for CIMT in a healthy population of college students. Given the study’s findings, we acknowledge that exposure to O3 may play an important role in the development of CIMT. However, based on the data provided in this study, we think that the authors should consider additional clinically relevant information that might help make the conclusion more convincing. It is well known that the risk factors associated with atherogenesis later in life are already present and observable in college-aged young adults, such as dietary pattern composition, blood pressure (BP) status during adolescence period, abnormal glucose metabolism, and so on. Now we will introduce the problems existing in this article in detail. First, the study did not analyze the information about the participants’ diet corresponding to the elementary school years (separately for ages 0–5 and 6–12 years) and lifetime exposure (from birth to date of CIMT measurement). Of note, the evidence has shown that subtle differences in dietary pattern composition affect the process of subclinical atherosclerosis.2 And dietary saturated fat is positively associated with artery calcium, whereas fiber and whole-grain intake can reduce progression of CIMT. Second, BP status during adolescence period of the participants is not taken into account. Because elevated BP at adolescence and a relative increase in BP from adolescence to adulthood unfavorably affect CIMT,3 these data should not be ignored in the analysis. Third, the most important deficit, however, is the lack of information on glucose metabolism of the participants. Previous studies have indicated that impaired glucose regulation categories increased vascular disease risk, as indicated by carotid/femoral intima–media thickness.4 Furthermore, even if normal glucose tolerance subjects with a 1-h postload glucose ≥155 mg/dL also have an atherogenic effects which is similar to impaired glucose tolerance individuals.5 Therefore, if all the participants have oral glucose tolerance test, it will be helpful in identification of the subjects who are at increased risk for CIMT. Nevertheless, the above important issues, which may limit the power to conclude an effect of childhood air pollutant on CIMT, were not discussed in this article. Finally, we believe that the applicative value of the result will be more instructive in real-world settings if the above information has been adjusted.Xi-Mei Wang, PhDYue-Jin Yang, MD, PhDYong-Jian Wu, MD, PhDDepartment of Cardiology, State Key Laboratory of Cardiovascular DiseaseFuwai Hospital, National Centre for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing, People’s Republic of ChinaDisclosuresNone.