Effect of air pollution on the autonomic modulation of heart rate in overweight adults

OBJECTIVE: To analyze the effect of air pollution on heart rate variability in overweight individuals. METHODS: A total of 46 adult individuals, both sexes, aged between 18 and 49 years and with body mass index >25kg/m(2) were analyzed. All volunteers were students from public schools of two cities in the state of São Paulo. The clinical, demographic and anthropometric data of each individual, as well as heart rate variability through time domain, geometric and frequency indices were collected. For the air quality analysis, the following variables were investigated: concentration of carbon dioxide, particulate matter, temperature and relative humidity. The analysis was carried out with descriptive and analytical statistics, adopting a level of significance of 5%. RESULTS: There was a reduction in overall heart rate variability in overweight individuals by the following indices: mean standard deviation of all normal RR intervals, long-term standard deviation of continuous RR intervals, ratio of short-and long-term standard deviation of continuous RR intervals. In addition, the indices responsible for parasympathetic control showed a downward trend in their values, as well as the low frequency index, which represented sympathetic action, although not significant. CONCLUSION: Overweight individuals exposed to air pollution had lower heart rate variability than the Control Group.