Asthma Is Greatest Risk Factor for Early COPD in U.S. Latino/a/x Communities

Older Male Patient Uses Spirometry - Respiratory Test

Chronic obstructive pulmonary disease (COPD) typically isn’t diagnosed until the patient is over 60 years old and doesn’t respond well to therapy because of substantial airflow obstruction. Many experts now suggest focusing on screening and interventions for “early” COPD, defined as COPD in individuals younger than 50.

Several studies in predominantly older white populations have identified various risk factors for early COPD, including smoking and asthma.

Now, Fariha Khalid, MD, MPH, a fellow in the Department of Anesthesiology, Perioperative and Pain Medicine at Brigham and Women’s Hospital, Alejandro A. Diaz, MD, MPH, a researcher in the Division of Pulmonary and Critical Care Medicine, and colleagues have conducted one of the largest studies of early COPD in U.S. Latino/a/x people. They report their findings in the Annals of the American Thoracic Society.

Methods

The researchers examined data from the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), which involved self-identified Latino/a/x men and women in households randomly selected from four U.S. communities. This analysis included 7,323 participants, ages 18 to 49 at baseline (2008–2011), who completed a respiratory questionnaire and spirometry.

Prevalence

The overall age- and sex-adjusted prevalence of early COPD was 7.6%. In a fully adjusted multivariable model, the prevalence was significantly higher in:

  • Ever-smokers vs. nonsmokers (<100 lifetime cigarettes)—8.6% vs. 5.3% (P=0.0005)
  • People with vs. without asthma—15.8% vs. 5.3% (P<0.001)
  • People with vs. without chronic sinusitis—10.0% vs. 6.1% (P=0.01)
  • U.S.-born Latino/a/x people vs. those who immigrated before at age <15 years and had lived in the U.S. ≥10 years—8.0% vs. 4.6% (P=0.005)
  • U.S.-born Latino/a/x people vs. those who immigrated at age ≥15 years and had lived in the U.S. ≥10 years—8.0% vs. 5.2% (P=0.03)

Risk Factors

Increased odds of early COPD were significantly associated with:

  • Asthma (adjusted OR (aOR), 3.37)
  • Chronic sinusitis (aOR, 1.71)
  • Ever-smoking (aOR, 1.65)

The odds of early COPD were lower for immigrants who had lived in the U.S. for ≥10 years (aOR, 0.55 for age at immigration <15 years; 0.63 for age at immigration ≥15 years).

Associations between these main exposures and early COPD differed by smoking status:

  • Never-smokers—Chronic sinusitis was not associated with early COPD
  • Ever-smokers—Pack-years smoked and immigration history were not associated with early COPD

Clinical Relevance

The overall prevalence of early COPD in this study is similar to the 8.2% prevalence in HCHS/SOL participants ages 45 and older, reported in the American Journal of Respiratory and Critical Care Medicine.

Furthermore, in 2018, Latino/a/xs accounted for 18% of the U.S. population, their median age was 30, and 48% were adults under 50, making them the largest and youngest racial/ethnic minority. These facts support the importance of preventive strategies against early COPD for individual patients and on the population level.

The influence of immigration history on the risk of early COPD may be at least partly attributable to different environmental exposures. For example, 80% of U.S. Latino/a/x people live in areas that don’t meet a single Environmental Protection Agency standard for clean air. Latino/a/x people born in the U.S. thus might have been exposed to respiratory hazards longer and during a more critical period of lung development than those who come from other countries.