title: Fine particulate matter results in hemodynamic changes in subjects with blunted nocturnal blood pressure dipping.
abstract: Particulate matter with aerodynamic diameter of <2.5 μm (PM2.5) is associated with blood pressure and hemodynamic changes. Blunted nocturnal blood pressure dipping is a major risk factor for cardiovascular events; limited information is available on whether PM2.5 exposure-related hemodynamic changes vary with day-night blood pressure circadian rhythms. In this study, we enrolled 161 subjects and monitored the changes in ambulatory blood pressure and hemodynamics for 24h. The day-night blood pressure and cardiovascular metrics were calculated according to the sleep-wake cycles logged in the subject׳s diary. The effects of PM2.5 exposure on blood pressure and hemodynamic changes were analyzed using generalized linear mixed-effect model. After adjusting for potential confounders, a 10-μg/m(3) increase in PM2.5 was associated with 1.0 mmHg [95% confidence interval (CI): 0.2-1.8 mmHg] narrowing in the pulse pressure, 3.1% (95% CI: 1.4-4.8%) decrease in the maximum rate of left ventricular pressure rise, and 3.6% (95% CI: 1.6-5.7%) increase in systemic vascular resistance among 79 subjects with nocturnal blood pressure dip of <10%. In contrast, PM2.5 was not associated with any changes in cardiovascular metrics among 82 subjects with nocturnal blood pressure dip of ≥10%. Our findings demonstrate that short-term exposure to PM2.5 contributes to pulse pressure narrowing along with cardiac and vasomotor dysfunctions in subjects with nocturnal blood pressure dip of <10%.
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan; Division of Surgical Intensive Care, Department of Critical Care Medicine, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan.
authors.forename: Szu-Ying
authors.initials: SY
authors.lastname: Chen
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan. Electronic address: ccchan@ntu.edu.tw.
authors.forename: Chang-Chuan
authors.initials: CC
authors.lastname: Chan
authors.affiliation: Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, Taipei, Taiwan.
authors.forename: Yu-Lun
authors.initials: YL
authors.lastname: Lin
authors.affiliation: Institute of Statistical Science, Academia Sinica, Taipei, Taiwan.
authors.forename: Jing-Shiang
authors.initials: JS
authors.lastname: Hwang
authors.affiliation: Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan. Electronic address: tachensu@ntu.edu.tw.
authors.forename: Ta-Chen
authors.initials: TC
authors.lastname: Su
mesh_terms: D000328:Adult; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002318:Cardiovascular Diseases / Q000209:etiology*; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D052638:Particulate Matter / Q000009:adverse effects*
chemical_list: D052638:Particulate Matter
keywords: Blood pressure; Cardiac contractility; Circadian rhythm; Particulate matter; Vascular resistance