ISEE 2007 CONFERENCE ABSTRACTS SUPPLEMENT: Abstracts
To study the relationship between personal exposure to PM2.5 and decrements of peak expiratory flow (PEF) in a group of Mexican adults with COPD.
Material and Methods:
Patients who had been diagnosed with moderate to severe COPD and were being followed up at the National Institute of Respiratory Diseases in Mexico City were invited to participate in this study. All participants were long-time residents of Mexico and were residing in the southeast, downtown, and southwest of the city. Participants were divided into 6 groups according to their place of residence. Each group was monitored continuously over a 2-week period. Groups were followed successively until each group was studied for at least 3 times. During follow-up, personal monitoring for PM2.5 was obtained at each participant, and we also obtained daily measurements of peak expiratory flow.
During the study period, the 24-hour average PM2.5 level was 38 μg/m3 (range, 4–141 μg/m3). The average peak flow for the morning and evening tests were 195 L/min (SD = 97) and 203 L/min (SD = 103), respectively. The decrement in the mean deviation of the evening PEF was −3.0 L/min (95% CI −5.7 to −0.3) with each 10 μg/m3 increase in the personal exposure to PM2.5 (2-days lag). On the 3 consecutive days (lag 3), it was associated with a decrement in the mean deviation in evening PEF of −3.6 L/min (95% CI −6.5 to −0.7)
This study confirms that particle concentrations in Mexico City are positively associated with decrements in peak expiratory flow in COPD adults.