Weekly SCD Practice Update

Elevated ambient nitrogen dioxide (NO₂) levels were associated with greater odds of abnormal pulmonary function tests in children and young adults with sickle cell disease (SCD), highlighting an environmental factor that may influence respiratory health in this population.

Key Findings

  • Purpose
    To evaluate whether ambient air pollution exposures, particularly criteria pollutants, are associated with abnormal pulmonary function tests (PFTs) among young people living with SCD.
  • Population
    Sixty-five children and young adults with SCD residing in Jefferson County, Alabama, with available first PFT per patient and linked monthly ambient air pollution data (2010–2019).
  • Headline Result
    Higher monthly average concentrations of nitrogen dioxide (NO₂) were significantly associated with increased odds of abnormal pulmonary function, specifically lower FEV₁ (large/medium airways indicator) (OR 1.53 per 1 ppb NO₂ increase; 95% CI 1.01–2.33; p = 0.047). Other pollutants were evaluated but did not show statistically significant associations in adjusted models.
  • Why It Matters
    Impaired pulmonary function in SCD is a major contributor to morbidity and mortality; identifying modifiable environmental exposures such as air pollution could inform risk stratification and preventive strategies in pediatric and young adult care.
  • Evidence Gaps & Limitations
    The observational design cannot establish causality; exposure was estimated at residential area level and may not reflect individual exposures. Sample size was modest, and the study was geographically limited, potentially affecting generalisability. Pulmonary function outcomes were not linked with clinical events (e.g., hospitalizations) in this analysis.

Source: Journal of Sickle Cell Disease — “Pulmonary function among children and young adults with sickle cell disease: the potential role of air pollution.

Regulatory & Guideline Watch

Guidelines do not specifically address environmental air pollution as a risk modifier for pulmonary dysfunction in SCD. However, broader public health standards (e.g., EPA National Ambient Air Quality Standards) aim to reduce NO₂ and other pollutant exposures given known respiratory health effects in vulnerable populations, which could be relevant for SCD care planning.