Prevalence of lifetime and current asthma in U.S. working adults: An analysis of the 1997–2004 National Health Interview Survey data

To estimate the national prevalence of lifetime and current asthma among U.S. workers by age, sex, race, occupation and industry for 1997–2004.

We analyzed the National Health Interview Survey data for 1997–2004 on respondents aged ≥18 years who were employed during the week prior to the interview. Asthma cases were defined based on positive responses to 1) ever being diagnosed with asthma by a physician (lifetime asthma); and 2) having an asthma attack in the past 12 months prior to the survey interview (current asthma).

The national estimated lifetime and current asthma prevalence among U.S. workers were 9.1% and 3.2%, respectively. Lifetime and current asthma prevalence were highest among younger (18–24 years) age group (12.8% and 4.2%); female former smokers (12.5% and 5.5%); and non-Hispanic whites (9.5% and 3.4%). Females had a significantly higher prevalence than males for lifetime (10.6% vs. 7.8%, P<.001) and current asthma (4.4% vs. 2.1%, P<.001). Social services, religious and membership organizations industry was associated with the highest lifetime (11.2%) and current (5.0%) asthma prevalence. Health services occupation was associated with the highest lifetime (11.5%) and current (5.1%) asthma prevalence.

The high asthma prevalence among certain industries and occupations suggests substantial contribution of occupational exposures to the overall burden of asthma. High asthma prevalence among females indicates a need for studies of the interactions between occupational exposures and non-occupational factors (e.g., smoking, gender) and their association with asthma.