Associations between air pollution and cardio-respiratory physiological measures in older adults exercising outdoors.

We examined whether exercising indoors vs. outdoors reduced the cardio-respiratory effects of outdoor air pollution. Adults ≥55 were randomly assigned to exercise indoors when the Air Quality Health Index was ≥5 and outdoors on other days (intervention group, n = 37), or outdoors everyday (control group, n = 35). Both groups completed cardio-respiratory measurements before and after exercise for up to 10 weeks. Data were analyzed using linear mixed effect regression models. In the control group, an interquartile range increase in fine particulate matter (PM2.5) was associated with increases of 1.4% in heart rate (standard error (SE) = 0.7%) and 5.6% (SE = 2.6%) in malondialdehyde, and decreases of 5.6% (SE = 2.5%) to 16.5% (SE = 7.5%) in heart rate variability measures. While the hypothesized benefit of indoor vs. outdoor exercise could not be demonstrated due to an insufficient number of intervention days (n = 2), the study provides evidence of short-term effects of air pollution in older adults. ISRCTN #26552763.

Cardiorespiratory Effects of Air Pollution in a Panel Study of Winter Outdoor Physical Activity in Older Adults.

OBJECTIVE: The aim of this study was to assess cardiorespiratory effects of air pollution in older adults exercising outdoors in winter. METHODS: Adults 55 years of age and older completed daily measurements of blood pressure, peak expiratory flow and oximetry, and weekly measurements of heart rate variability, endothelial function, spirometry, fraction of exhaled nitric oxide and urinary oxidative stress markers, before and after outdoor exercise, for 10 weeks. Data were analyzed using linear mixed effect models. RESULTS: Pooled estimates combining 2014 (n = 36 participants) and 2015 (n = 34) indicated that an interquartile increase in the Air Quality Health Index was associated with a significant (P < 0.05) increase in heart rate (0.33%) and significant decreases in forced expiratory volume (0.30%), and systolic (0.28%) and diastolic blood pressure (0.39%). CONCLUSION: Acute subclinical effects of air pollution were observed in older adults exercising outdoors in winter.

Cardio-Respiratory Effects of Air Pollution in a Panel Study of Outdoor Physical Activity and Health in Rural Older Adults.

OBJECTIVE: To examine cardio-respiratory effects of air pollution in rural older adults exercising outdoors. METHODS: Adults 55 and over completed measurements of blood pressure, peak expiratory flow and oximetry daily, and of heart rate variability, endothelial function, spirometry, fraction of exhaled nitric oxide and urinary oxidative stress markers weekly, before and after outdoor exercise, for 10 weeks. Data were analyzed using linear mixed effect models. RESULTS: Pooled estimates combining 2013 (n = 36 participants) and 2014 (n = 41) indicated that an interquartile increase in the air quality health index (AQHI) was associated with a significant (P < 0.05) increase in heart rate (2.1%) and significant decreases in high frequency power (-19.1%), root mean square of successive differences (-9.5%), and reactive hyperemia index (-6.5%). CONCLUSIONS: We observed acute subclinical adverse effects of air pollution in rural older adults exercising outdoors.

The association between ambient air quality and cardiac rate and rhythm in ambulatory subjects.

BACKGROUND: Acute increases in ambient air pollution have been associated with increased hospitalization for cardiac diseases and stroke. Triggering of cardiac arrhythmia by changes in air quality could theoretically predispose individuals to cardiac arrest or heart failure, or stroke through precipitation of atrial fibrillation. We investigated the association between air quality and cardiac rate and rhythm characteristics measured by ambulatory cardiac monitoring. METHODS AND RESULTS: Daily ambient 3-h maximum concentrations of ozone, nitrogen dioxide and fine particulate matter, and an index summarizing these pollutants called the Air Quality Health Index (AQHI) were compared to the results of 24-h ambulatory cardiac monitoring performed for clinical purposes in 8662 patients and analyzed at the University of Ottawa Heart Institute, Canada, between 2004 and 2009. An interquartile increase in the daily 3 h- maximum AQHI was associated with a 0.9% (95% CI 0.3%, 1.5%) increase in the daily maximum heart rate and a 1.17% (95% CI 1.07%, 1.29%) increase in heart block frequency. An interquartile increase in NO2 was associated with an increase in the percentage of time in atrial fibrillation of 4.39% (-0.15, 9.15) among those ≤50 years old, and 7.1% (0.24, 14.5) among males. CONCLUSIONS: We found evidence that air pollution may affect cardiac rate and rhythm. This may be one mechanism partially explaining the increase in strokes and cardiac events observed on days of higher air pollution.