Prevalence Rates of COPD Among Nonsmokers Vary by Occupation

A new study has found that between 2013 and 2017, out of the 2.4 million working adults in the United States with chronic obstructive pulmonary disease (COPD) who never smoked cigarettes, the highest rates of COPD were found among office and administrative support workers and those who worked in mining and information industries, according to CDC’s Morbidity and Mortality Weekly Report.

An estimated 24% of adults with COPD have never smoked. Among these individuals, 26% to 53% of COPD occurrences can be attributed to a variety of workplace exposures including dust, fumes, gases, vapors, second-hand smoke exposure, and other causes.

CDC analyzed National Health Interview Survey (NHIS) data from 2013 to 2017 to assess industry and occupation-specific COPD prevalence rates among adults 18 or more years old who have never smoked and were employed any time during the past year.

Participants with COPD were identified by a positive response to a series of questions including:

• Have you ever been told by a doctor or other health professional that you had chronic obstructive pulmonary disease, also called COPD?
• Have you ever been told by a doctor or other health professional that you had emphysema?
• During the past 12 months, have you been told by a doctor or other health professional that you had chronic bronchitis?

Among approximately 106 million workers who had never smoked, 2.2% had COPD. Prevalence rates of the disease for nonsmokers were:

• 10.3% among individuals with more that 3 emergency department visits in the past year
• 6.7% among individuals who reported fair or poor health
• 6.6% among individuals who lost more than 7 days of work due to illness or injury
• 4.6% among individuals 65 or more years old
• 4.2% among individuals with 3 or more physician office visits in the past year
• 3.0% among women

Individuals with COPD who never smoked missed an average of 14.9 work days per year due to an illness or injury compared to an average of 5.4 missed by individuals who did not have COPD.

Reflecting industry and occupation, highest COPD prevalence rates among workers who never smoked were:

• 3.3% for those in the information industry
• 3.3% for those in office and administrative support
• 3.1% for those in the mining industry

Gender was found to account for differences in COPD prevalence by occupation among nonsmokers. Among men, the highest COPD prevalence rates were:

• 2.3% for those employed in agriculture, forestry, fishing, and hunting
• 2.3% for those employed in administration and support, waste management, and remediation services
• 2.3% for those employed in art, entertainment, and recreation industries
• 2.3% for those employed in protective services occupation

Among female nonsmokers, the highest COPD prevalence rates by occupation were:

• 5.1% for those employed in the information industry
• 4.5% for those employed in the transportation and material moving industry

The study also found that women accounted for 66% of all nonsmokers with COPD who were employed within the last year.

Respondents who had smoked 100 or less cigarettes in their lifetime were considered to have never smoked. Those who smoked more than 100 cigarettes were considered to have ever smoked. Respondents self-reported health status at the time of interview, the number of physician office and emergency department visits, and the number of work days lost within the past year due to illness of injury.

NHIS data were collected annually from a nationally representative sample of the United States population through a personal interview. Data collected during 2013 to 2017 were combined to improve the precision and reliability of estimates. Survey response rates ranged from 61.2% in 2013 to 53.0% in 2017. Data on participants’ current industry and occupation were categorized into 21 industry groups and 23 occupation groups.

Researchers analyzed data using SAS version 9.4. Respondents with unknown or missing information for COPD were excluded from the analysis. Statistically significant differences between point estimates were determined by 2-sided t-tests.

The observation of high rates of COPD among workers who never smoked supports the hypothesis that occupational exposures may contribute to the development of COPD. Researchers believe that identifying occupational risk factors, making efforts to reduce adverse workplace exposures, and promoting research to characterize risk factors for COPD are crucial for preventing and reducing COPD among nonsmoking workers.

Reference

Syamlal G, Doney B, Mazurek JM. Chronic obstructive pulmonary disease prevalence among adults who have never smoked, by industry and occupation — United States, 2013—2017 [published online April 5, 2019]. MMWR Morb Mortal Wkly Rep. 2019;68(13):303—307. doi: 10.15585/mmwr.mm6813a2.