Prenatal household air pollution exposure poses infection risk in infants

Exposure to household air pollution during pregnancy may put babies at risk of developing pneumonia, including severe infection, in their first year of life, a study has found.

Close to 40 percent of the world’s population is said to be exposed daily to household air pollution. So, a team of researchers conducted the Ghana Randomized Air Pollution and Health Study (GRAPHS) to examine the relative impact of prenatal and postnatal household air pollution exposure on early childhood pneumonia, which is a leading cause of mortality.

The study enrolled a total of 1,414 nonsmoking, pregnant women prior to 24 weeks gestation. All of them were followed until their children turned 12 months.

The researchers measured 72-hour personal household air pollution exposures, indexed by carbon monoxide (CO), four times during pregnancy and three times following delivery. They conducted weekly surveillance to identify ill-appearing children for physician pneumonia assessment.

A total of 1,141 out of the 1,306 infants were followed with 55,605 child-weeks of fieldworker surveillance. In quasi-Poisson models, every 1-ppm increase in average prenatal CO exposure upped the risk of pneumonia by 10 percent (relative risk [RR], 1.10, 95 percent confidence interval [CI], 1.04–1.16) and of severe pneumonia by 15 percent (RR, 1.15, 95 percent CI, 1.03–1.28) in the first year of life.

Meanwhile, every 1-ppm increase in average postnatal CO exposure contributed to a 6-percent risk increase (RR, 1.06, 95 percent CI, 0.99–1.13).

Female infants appeared more vulnerable than males.

The findings suggest that clean burning interventions may be most effective when begun prenatally, according to the researchers.