Spatial analysis of tobacco outlet density on secondhand smoke exposure and asthma health among children in Baltimore City

RATIONALE

Tobacco outlets are concentrated in low-income neighbourhoods; higher tobacco outlet density is associated with increased smoking prevalence. Secondhand smoke (SHS) exposure has significant detrimental effects on childhood asthma. We hypothesised there was an association between higher tobacco outlet density, indoor air pollution and worse childhood asthma.

METHODS

Baseline data from a home intervention study of 139 children (8-17 years) with asthma in Baltimore City included residential air nicotine monitoring, paired with serum cotinine and asthma control assessment. Participant addresses and tobacco outlets were geocoded and mapped. Multivariable regression modelling was used to describe the relationships between tobacco outlet density, SHS exposure and asthma control.

RESULTS

Within a 500 m radius of each participant home, there were on average six tobacco outlets. Each additional tobacco outlet in a 500 m radius was associated with a 12% increase in air nicotine (p<0.01) and an 8% increase in serum cotinine (p=0.01). For every 10-fold increase in air nicotine levels, there was a 0.25-point increase in Asthma Therapy Assessment Questionnaire (ATAQ) score (p=0.01), and for every 10-fold increase in serum cotinine levels, there was a 0.54-point increase in ATAQ score (p<0.05).

CONCLUSIONS

Increased tobacco outlet density is associated with higher levels of bedroom air nicotine and serum cotinine. Increasing levels of SHS exposure (air nicotine and serum cotinine) are associated with less controlled childhood asthma. In Baltimore City, the health of children with asthma is adversely impacted in neighbourhoods where tobacco outlets are concentrated. The implications of our findings can inform community-level interventions to address these health disparities.

An 18-year-old woman with pulmonary nodules found to have cytotoxic T-lymphocyte-associated antigen 4 deficiency

An 18-year-old woman was admitted with abdominal pain and hematochezia. She was previously healthy until 15 years of age and was subsequently diagnosed with hypogammaglobulinemia, protein-losing enteropathy, a benign temporal lobe brain lesion/orbital fibroadenoma, autoimmune hepatitis, iron deficiency anaemia and hypothyroidism. She developed respiratory distress and hypoxemia. She was found to have nodules on chest CT scan. She was diagnosed with cytotoxic T-lymphocyte-associated antigen 4 deficiency via genetic testing.

Health-care utilization and respiratory morbidities in preterm infants with pulmonary hypertension

OBJECTIVE

To assess health-care utilization and risk of respiratory morbidities in preterm infants with bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH).

STUDY DESIGN

Retrospective data were obtained from subjects (n=109) attending a BPD clinic. Subjects were stratified by the presence or absence of PH before and after 2 months of age. Analytic methods included t-tests, χ(2) tests and regression.

RESULT

Subjects with BPD and PH present after 2 months of age were hospitalized for 2.2 months longer than those without PH (P=0.02). These subjects were 4.5 times more likely to receive home supplemental oxygen or mechanical ventilation (P=0.03). No difference in the risk of respiratory morbidities after initial hospital discharge was seen with PH.

CONCLUSION

PH in preterm infants is associated with longer initial hospitalizations and a higher likelihood of requiring home respiratory support. This has implications for counseling families and reducing the medical, psychosocial, and economic burden of BPD and PH.

Environmental Modifiers of Chronic Lung Disease of Prematurity During Infancy

Chronic lung disease is a common complication of prematurity with substantial mortality and morbidity. Although the variation seen in bronchopulmonary dysplasia has a strong genetic component, the limited environmental variation in neonatal intensive care units may lead to underestimates of the contribution of environmental factors to lung disease variation. Once discharged from the hospital, preterm infants are exposed to a variety of environmental factors that likely worsen their disease. Recognition of these factors may lead to improved outcomes in this vulnerable population through more effective guidelines and counseling. This review examines the role of selected outpatient environmental factors on respiratory outcomes during infancy in preterm infants with lung disease.