Particulate Matter Exposure and Preterm Birth: Estimates of U.S. Attributable Burden and Economic Costs

Table 2. Estimated economic costs of PM2.5-attributable preterm births.
Parameter Base scenarioa Low scenarioa High scenarioa
IQR, interquartile range.
aBase scenario estimates are based on OR of 1.15; low and high scenario estimates are based on ORs of 1.07 and 1.16, respectively. For calculations, please see “Methods.”
bMedian RR estimated using the MEDIAN function in Excel (Microsoft).
cLost economic productivity due to reduced cognitive potential was measured as an indirect cost of PM2.5-attributable PTB. PTB-associated IQ loss was calculated using data from a systematic review that estimates an 11.9-point IQ decrement on average in PTB children (95% CI: 10.5, 13.4). See “Methods.”
dTwo types of direct costs of PTB were estimated: costs for treatment of PTB-associated medical conditions in the first 5 years of life, and costs after the first 5 years of life due to PTB-associated developmental disability. See “Methods.”
Range of relative risks 1.000–1.352 1.000–1.159 1.000–1.429
Median relative risk (IQR)b 1.003 (1.000–1.045) 1.002 (1.000–1.021) 1.043 (1.011–1.089)
Percentage with RR above 1 (RR = 1 indicates risk unchanged) 63.4% 63.4% 91.7%
Attributable fraction 3.32% 1.58% 6.30%
Attributable preterm births (n) 15,808 7,532 29,968
Lost economic productivity, PM2.5-attributable preterm birthsc $4.33 billion $2.06 billion $8.22 billion
Additional medical care, PM2.5-attributable preterm birthsd $760 million $362 million $1.44 billion
Total costs, PM2.5-attributable preterm births $5.09 billion $2.43 billion $9.66 billion