The Effects of Household Air Pollution (HAP) on Lung Function in Children: A Systematic Review

Effect of dietary antioxidant quality score on tobacco smoke exposure and asthma in children and adolescents: a cross-sectional study from the NHANES database

BACKGROUND

Asthma is a common non-communicable disease in children, and airway inflammation is the main pathological change of asthma. Tobacco smoke exposure (TSE) can cause systematic inflammation and oxidative stress, which may further aggravate the progression of asthma. Dietary antioxidants can relieve the inflammation and oxidative stress in human body. This study aims to assess the effect of overall antioxidant capacity of dietary intake, evaluating by dietary antioxidant quality score (DAQS), in the association between TSE and childhood asthma.

METHODS

Data of this cross-sectional study were extracted from the National Health and Nutrition Examination Surveys (NHANES) 2007-2018. DAQS was calculated based on the daily dietary intake of selenium, zinc, magnesium, vitamin A, C and E. TSE was measured by serum cotinine concentration. The weighted univariate and multivariate logistic regression models were employed to evaluate the role of DAQS in the association between TSE and asthma among children and adolescents. Subgroup analysis was conducted to further evaluate the association based on gender.

RESULTS

Totally 11,026 children and adolescents were included, of whom 1,244 (11.28%) had asthma. After adjusted all covariates, TSE was associated with the high odds of childhood asthma (OR = 1.26, 95%CI = 1.05-1.52). Among children exposed to tobacco smoke, those with higher DAQS level (OR = 1.15, 95%CI: 0.88-1.50) had a reduced risk of asthma compared with those children with lower DAQS level (OR = 1.43, 1.08-1.89), especially among girls (OR = 1.42, 95%CI: 0.93-2.17).

CONCLUSION

High DAQS may have a moderating effect on asthma in children; that is, the higher DAQS, the lower the odds of asthma in children who exposed to tobacco smoke. Our study provides a reference for developing more targeted strategies for prevention and treatment of asthma in children.

Association between adherence to a lifestyle behavior and the risk of asthma in overweight and obese adolescents

With the increasing prevalence of overweight and obesity in children and adolescents, to actively prevent the occurrence of asthma in this population is important for reducing the burden of the disease. Lifestyle factors, including diet and exercise, are importance for overweight and obese adolescents, as well as an important modifiable factor affecting airway inflammation and asthma, whether healthy lifestyle was correlated with the risk of asthma in adolescents ≥ 12 years has not been reported. We suspected that there might be correlation between healthy lifestyle behaviors and the risk of asthma in overweight and obese adolescents. This cross-sectional study aimed to explore the association between the adherence to a healthy lifestyle behaviors and the risk of asthma in overweight and obese adolescents based on the data of 945 participants aged between 12-18 years from the National Health and Nutrition Examination Surveys (NHANES). Univariable and multivariable weighted Logistic regression models were applied to evaluate the association between healthy lifestyle behaviors with asthma risk in overweight and obese adolescents. Odds ratio (OR) and 95% confidence interval (CI) were applied as estimates. We found that the risk of asthma was reduced in overweight and obese adolescents with intermediate (OR = 0.40, 95%CI: 0.17-0.94) or good lifestyle behaviors (OR = 0.33, 95%CI: 0.13-0.86) in comparison to those with poor lifestyle behaviors. In summary, intermediate or good lifestyle behaviors was correlated with decreased risk of asthma in overweight and obese adolescents, which might provide a reference for making further prevention strategies for asthma in adolescents.

Household Air Pollution and Child Lung Function: The Ghana Randomized Air Pollution and Health Study

Rationale: The impact of a household air pollution (HAP) stove intervention on child lung function has been poorly described. Objectives: To assess the effect of a HAP stove intervention for infants prenatally to age 1 on, and exposure-response associations with, lung function at child age 4. Methods: The Ghana Randomized Air Pollution and Health Study randomized pregnant women to liquefied petroleum gas (LPG), improved biomass, or open-fire (control) stove conditions through child age 1. We quantified HAP exposure by repeated maternal and child personal carbon monoxide (CO) exposure measurements. Children performed oscillometry, an effort-independent lung function measurement, at age 4. We examined associations between Ghana Randomized Air Pollution and Health Study stove assignment and prenatal and infant CO measurements and oscillometry using generalized linear regression models. We used reverse distributed lag models to examine time-varying associations between prenatal CO and oscillometry. Measurements and Main Results: The primary oscillometry measure was reactance at 5 Hz, X5, a measure of elastic and inertial lung properties. Secondary measures included total, large airway, and small airway resistance at 5 Hz, 20 Hz, and the difference in resistance at 5 Hz and 20 Hz (R5, R20, and R5-20, respectively); area of reactance (AX); and resonant frequency. Of the 683 children who attended the lung function visit, 567 (83%) performed acceptable oscillometry. A total of 221, 106, and 240 children were from the LPG, improved biomass, and control arms, respectively. Compared with control, the improved biomass stove condition was associated with lower reactance at 5 Hz (X5 z-score: β = -0.25; 95% confidence interval [CI] = -0.39, -0.11), higher large airway resistance (R20 z-score: β = 0.34; 95% CI = 0.23, 0.44), and higher AX (AX z-score: β = 0.16; 95% CI = 0.06, 0.26), which is suggestive of overall worse lung function. The LPG stove condition was associated with higher X5 (X5 score: β = 0.16; 95% CI = 0.01, 0.31) and lower small airway resistance (R5-20 z-score: β = -0.15; 95% CI = -0.30, 0.0), which is suggestive of better small airway function. Higher average prenatal CO exposure was associated with higher R5 and R20, and distributed lag models identified sensitive windows of exposure between CO and X5, R5, R20, and R5-20. Conclusions: These data support the importance of prenatal HAP exposure on child lung function. Clinical trial registered with www.clinicaltrials.gov (NCT01335490).

Association Between Maternal Prenatal Exposure to Household Air Pollution and Child Respiratory Health: A Systematic Review and Meta-analysis

Maternal prenatal exposure to household air pollution (HAP) is a critical public health concern with potential long-term implications for child respiratory health. The objective of this study is to assess the level of association between prenatal household air pollution and child respiratory health, and to identify which HAP pollutants are associated with specific respiratory illnesses or symptoms and to what degree. Relevant studies were retrieved from PubMed databases up to April 27, 2010, and their reference lists were reviewed. Random effects models were applied to estimate summarized relative risks (RRs) and 95% confidence intervals (CIs). The analysis involved 11 studies comprising 387 767 mother-child pairs in total, assessing various respiratory health outcomes in children exposed to maternal prenatal HAP. Children with prenatal exposure to HAP pollutants exhibited a summary RR of 1.26 (95% CI=1.08-1.33) with moderate between-study heterogeneity (I²=49.22%) for developing respiratory illnesses. Specific associations were found between prenatal exposure to carbon monoxide (CO) (RR=1.11, 95% CI: 1.09-1.13), Nitrogen Oxides (NOx) (RR=1.46, 95% CI: 1.09-1.60), and particulate matter (PM) (RR=1.26, 95% CI: 1.2186-1.3152) and child respiratory illnesses (all had I² close to 0%, indicating no heterogeneity). Positive associations with child respiratory illnesses were also found with ultrafine particles (UFP), polycyclic aromatic hydrocarbons (PAH), and ozone (O3). However, no significant association was observed for prenatal exposure to sulfur dioxide (SO2). In summary, maternal prenatal exposure to HAP may contribute to a higher risk of child respiratory health issues, emphasizing the need for interventions to reduce this exposure during pregnancy. Targeted public health strategies such as improved ventilation, cleaner cooking technologies, and awareness campaigns should be implemented to minimize adverse respiratory effects on children.

The impact of antenatal and postnatal indoor air pollution or tobacco smoke exposure on lung function at 3 years in an African birth cohort

BACKGROUND AND OBJECTIVE

Indoor air pollution (IAP) and tobacco smoke exposure (ETS) are global health concerns contributing to the burden of childhood respiratory disease. Studies assessing the effects of IAP and ETS in preschool children are limited. We assessed the impact of antenatal and postnatal IAP and ETS exposure on lung function in a South African birth cohort, the Drakenstein Child Health Study.

METHODS

Antenatally enrolled mother-child pairs were followed from birth. Lung function measurements (oscillometry, multiple breath washout and tidal breathing) were performed at 6 weeks and 3 years. Quantitative antenatal and postnatal IAP (particulate matter [PM10 ], volatile organic compounds [VOC]) and ETS exposures were measured. Linear regression models explored the effects of antenatal and postnatal exposures on lung function at 3 years.

RESULTS

Five hundred eighty-four children had successful lung function testing, mean (SD) age of 37.3 (0.7) months. Exposure to antenatal PM10 was associated with a decreased lung clearance index (p < 0.01) and postnatally an increase in the difference between resistance at end expiration (ReE) and inspiration (p = 0.05) and decrease in tidal volume (p = 0.06). Exposure to antenatal VOC was associated with an increase in functional residual capacity (p = 0.04) and a decrease in time of expiration over total breath time (tE /tTOT ) (p = 0.03) and postnatally an increase in respiratory rate (p = 0.05). High ETS exposure postnatally was associated with an increase in ReE (p = 0.03).

CONCLUSION

Antenatal and postnatal IAP and ETS exposures were associated with impairment in lung function at 3 years. Strengthened efforts to reduce IAP and ETS exposure are needed.

Lower socioeconomic status strengthens the effect of cooking fuel use on anemia risk and anemia-related parameters: Findings from the Henan Rural Cohort

The established evidence of cooking fuel use and socioeconomic status related to anemia is limited in low- and middle-income countries. The current study aims to examine the independent and combined effects of cooking fuel use and socioeconomic status on anemia risk as well as anemia-related parameters in rural China. A total of 21,050 participants were included from the baseline of the Henan Rural Cohort. Anemia was determined according to the World Health Organization criteria. Data on cooking fuel use (electricity, gas and solid fuel) and socioeconomic status (education and income levels) were collected using a standardized questionnaire by face-to-face interview. Logistic and linear regression models were applied to evaluate the effects of cooking fuel use or socioeconomic indicators on anemia risk, hemoglobin (HGB), red blood count (RBC), and hematocrit (HCT) levels. Using gas or solid fuel for cooking was positively associated with prevalent anemia risk and negatively related to HGB, RBC, and HCT levels compared to using electricity. Significant independent associations were also found between socioeconomic status (education and income levels) and prevalent anemia risk as well as these anemia-related parameters. In general, with decreased socioeconomic status, associations of using gas or solid fuel for cooking with advanced anemia risk as well as lower anemia-related parameters were increased. Furthermore, participants using gas or solid fuel for cooking and with lower education or income level were related to increased high anemia risk as well as low HGB, RBC and HCT levels, compared to those using electricity for cooking and with high education or income level (P <0.05 for all). The finding suggested that lower socioeconomic status strengthens the adverse effect of cooking fuel use on the higher anemia risk and lower HGB, RBC, and HCT levels in rural China.

Association of ambient and household air pollution with lung function in young adults in an peri-urban area of South-India: A cross-sectional study

OBJECTIVE

Although there is evidence for the association between air pollution and decreased lung function in children, evidence for adolescents and young adults is scarce. For a peri-urban area in India, we evaluated the association of ambient PM_2.5 and household air pollution with lung function for young adults who had recently attained their expected maximum lung function.

METHODS

We measured, using a standardized protocol, forced expiratory volume in the first second (FEV₁) and forced vital capacity (FVC) in participants aged 20-26 years from the third follow-up of the population-based APCAPCS cohort (2010-2012) in 28 Indian villages. We estimated annual average PM_2.5outdoors at residence using land-use regression. Biomass cooking fuel (a proxy for levels of household air pollution) was self-reported. We fitted a within-between linear-mixed model with random intercepts by village, adjusting for potential confounders.

RESULTS

We evaluated 1,044 participants with mean age of 22.8 (SD = 1) years (range 20-26 years); 327 participants (31%) were female. Only males reported use of tobacco smoking (9% of all participants, 13% of males). The mean ambient PM_2.5 exposure was 32.9 (SD = 2.8) µg/m³; 76% reported use of biomass as cooking fuel. The adjusted association between 1 µg/m³ increase in PM_2.5 was -27 ml (95% CI, -89 to 34) for FEV₁ and -5 ml (95% CI, -93 to 76) for FVC. The adjusted association between use of biomass was -112 ml (95% CI, -211 to -13) for FEV₁ and -142 ml (95% CI, -285 to 0) for FVC. The adjusted association was of greater magnitude for those with unvented stove (-158 ml, 95% CI, -279 to -36 for FEV₁ and -211 ml, 95% CI, -386 to -36 for FVC).

CONCLUSIONS

We observed negative associations between ambient PM_2.5 and household air pollution and lung function in young adults who had recently attained their maximum lung function.