Prenatal fine particulate exposure and early childhood asthma: Effect of maternal stress and fetal sex

Abstract

Prenatal PM exposure during sensitive windows is associated with increased risk of child asthma, especially in boys concurrently exposed to elevated maternal stress.

Spatiotemporal Variations in Ambient Ultrafine Particles and the Incidence of Childhood Asthma

“…Specifically, we previously reported that exposures to PM2.5 and NO2 during the second trimester of pregnancy were associated with childhood asthma incidence (18). In a study conducted in Boston, Massachusetts, authors found that exposure to PM2.5 during pregnancy was associated with asthma incidence in children by age 6 years only during weeks corresponding to the second trimester of pregnancy (10,15). In addition, results based on 2,598 children enrolled in a study in China found that second trimester exposure to NO2 was associated with asthma incidence (OR = 1.72, 95% CI: 1.02, 2.97) (14).…”

“…Several epidemiological studies have reported positive associations between exposure to air pollution and incidence of childhood asthma (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). Among those studies, some reported associations between exposure to air pollution, in particular PM2.5 and to a lesser extent NO2, during the prenatal period and asthma onset in children (10,14,15). Despite the documented effects of particulate air pollution on childhood asthma incidence and concerns that UFPs might be more toxic than the larger particulate matter, the effects of UFPs on asthma onset in children are not well studied.…”

“…The prevalence of asthma in children has been increasing worldwide over the last decades (1)(2)(3). Evidence links ambient air pollution exposures during pregnancy and early life with lung function deficits in children (4-7) as well as childhood asthma incidence (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). While most studies have focused on traffic-related air pollutants such as nitrogen oxides (NOx) and particulate matter (PM), there is still considerable uncertainty as to whether these pollutants are primarily responsible for the observed adverse effects.…”

Emerging concepts and challenges in implementing the exposome paradigm in allergic diseases and asthma: a Practall document

“…One is the prenatal time period, as Hsu et al., demonstrated using satellite‐based spatiotemporal measures to model daily PM 2.5 exposures throughout pregnancy on physician diagnosis of asthma by age 6 years, mid‐pregnancy at 16‐25 weeks' gestation, especially for boys . When PM 2.5 measures are combined with maternal stress exposure, the prenatal time window of susceptibility may narrow to 19‐23 weeks . When NO 3 − measures are combined with high maternal stress, pregnancy remains a key period…”

Can the effects of outdoor air pollution on asthma be mitigated?

“…In a birth cohort study prenatal exposure to nitrate or coarse particulate matter measuring less than 2.5 mm in diameter (PM 2.5 ) was significantly associated with asthma and reduced lung function at age 6 years in boys exposed to chronic stress but not in girls. 2 In another birth cohort postnatal NO 2 exposure was associated with asthma in children with high lifetime exposure to violence but not in those with lower lifetime exposure to violence. Similarly, longitudinal studies found that postnatal exposure to total oxides of nitrogen and other forms of trafficrelated air pollution (TRAP) were linked to asthma and reduced lung function in children whose parents were highly stressed.…”