Modification of the association between ambient air pollution and lung function by frailty status among older adults in the Cardiovascular Health Study.
The susceptibility of older adults to the health effects of air pollution is well-recognized. Advanced age may act as a partial surrogate for conditions associated with aging. The authors investigated whether gerontologic frailty (a clinical health status metric) modified the association between ambient level of ozone or particulate matter with an aerodynamic diameter less than 10 µm and lung function in 3,382 older adults using 7 years of follow-up data (1990-1997) from the Cardiovascular Health Study and its Environmental Factors Ancillary Study. Monthly average pollution and annual frailty assessments were related to up to 3 repeated measurements of lung function using cumulative summaries of pollution and frailty histories that accounted for duration as well as concentration. Frailty history was found to modify long-term associations of pollutants with forced vital capacity. For example, the decrease in forced vital capacity associated with a 70-ppb/month greater cumulative sum of monthly average ozone exposure was 12.3 mL (95% confidence interval: 10.4, 14.2) for a woman who had spent the prior 7 years prefrail or frail as compared with 4.7 mL (95% confidence interval: 3.8, 5.6) for a similar woman who was robust during all 7 years (interaction P < 0.001).
Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, USA. eckel@usc.edu
Sandrah P
SP
Eckel
Thomas A
TA
Louis
Paulo H M
PH
Chaves
Linda P
LP
Fried
And Helene G
AH
Margolis
D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005541:Forced Expiratory Volume; D016330:Frail Elderly / Q000706:statistics & numerical data; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012129:Respiratory Function Tests / Q000706:statistics & numerical data; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D014797:Vital Capacity