Preconceptional and prenatal exposure to diurnal temperature variation increases the risk of childhood pneumonia

Abstract

Background Pneumonia is the leading cause of death and hospitalization among young children worldwide, but its risk factors remain unclear. Objective To evaluate the effect of maternal exposure to diurnal temperature variation (DTV) during preconceptional and prenatal periods on childhood pneumonia. Methods A retrospective cohort study by case-control design was conducted for pneumonia (N = 699) and normal (N = 811) children under age of 14 who were enrolled in XiangYa Hospital, Changsha, China from May 2017 to April 2019. Demographic data including gender, age, birth season, gestational age, parity, mode of delivery, and parental atopy were collected from the electronic medical records in the hospital system. We obtained the data of daily DTV in Changsha during 2003–2019 from China Meteorological Administration. Maternal exposure to DTV during preconceptional and prenatal periods was respectively calculated by the average of daily DTV during one year and three months before conception and entire pregnancy as well as the three trimesters. The association between maternal exposure to outdoor DTV and childhood pneumonia was analyzed by multiple logic regression model. Results We found that childhood pneumonia was significantly associated with exposure to an increase in DTV during one year before conception and entire pregnancy, with ORs (95 % CI) = 2.53 (1.56–4.10) and 1.85 (1.24–2.76). We further identified a significant risk of pneumonia of DTV exposure during the first and second trimester of pregnancy. Sensitivity analysis showed that boys were more susceptible to the effect of prenatal exposure to outdoor DTV during pregnancy particularly in the first two trimesters compared to girls. Conclusions Preconceptional and prenatal exposure to DTV plays an important role in development of childhood pneumonia, especially during the first and second trimesters of pregnancy.

Association of Prenatal and Postnatal Exposures to Warm or Cold Air Temperatures With Lung Function in Young Infants

“…Direct temperature exposure during the postnatal period could act on the respiratory system as well as on risk factors (eg, allergens) of altered lung function. 12 Contrary to previous research, 14,18,19,37 female newborns appeared more sensitive to both cold and heat than male newborns. However, previous studies 23,38 were performed on older populations and considered different lung function measurements.…”

“…20 In addition, male and female populations show differences in lung growth and airway development, [21][22][23] lending support to differential responses to environmental stressors. 14,18,19 This finding paves the way for the investigation of sex-specific critical windows of susceptibility. We leveraged lung function measurements performed in newborns of the SEPAGES (Suivi de l'Exposition à la Pollution Atmosphérique durant la Grossesse et Effets sur la Santé [Assessment of Air Pollution Exposure During Pregnancy and Effect on Health]) mother-child cohort and a cutting-edge spatiotemporal model of ambient temperature exposure combined with distributed lag models to explore the associations between prenatal and postnatal long-term and short-term temperature exposures and male and female newborn lung function.…”

“…12,13 Decreased forced vital capacity 14 and peak expiratory flow [15][16][17] have been associated with short-term and long-term exposure to extreme temperatures in healthy children or children with asthma. During pregnancy, high diurnal temperature variations have been associated with significant increase of pneumonia diagnosis 18 and the common cold in children. 19 To date, no study has investigated the association of maternal heat or cold exposure with lung function in newborns.…”

Maternal Apparent Temperature During Pregnancy on the Risk of Offspring Asthma and Wheezing: Effect, Critical Window, And Modifiers

“…For instance, a prospective cohort study conducted in China among 2598 children found that prenatal exposure to diurnal temperature variation was signi cantly associated with the incidence of pneumonia in children aged 3-6 years (Miao, et al 2017). Similarly, Lu et al carried out a cohort study and discovered that childhood pneumonia was signi cantly associated with increased exposure to diurnal temperature differences throughout the entire pregnancy (Zheng, et al 2021). Apparently, the results of these studies suggest that extreme AT during pregnancy is associated with the risk of respiratory disease in the offspring.…”

“…Prenatal exposure to harmful environmental factors could harm organ development as well as infancy growth and could increase the risk of respiratory diseases in childhood (Gluckman, et al 2008). A study suggested that prenatal exposure to diurnal temperature variation plays an important role in the development of childhood pneumonia (Zheng, et al 2021). Also, the common cold in children was associated with prenatal exposure to air temperature variation (Lu, et al 2018).…”