COPD Among Smokers and Never-Smokers in the United States, 2017

Cigarette smoking is the leading cause of chronic obstructive pulmonary disease (COPD) in the United States — yet about a quarter of adults with COPD have never smoked. A CDC analysis of 2017 survey data found something that points to one reason: in states where more people smoke, more people who have never smoked have COPD too.

COPD among U.S. adults by state, 2017: all adults, current smokers, former smokers and people who never smoked. Credit: CDC, Morbidity and Mortality Weekly Report.

The numbers

The Behavioral Risk Factor Surveillance System, a telephone survey run by state health departments with CDC, reached 418,378 adults in all 50 states and the District of Columbia in 2017. COPD meant having been told by a doctor, nurse or other health professional that one had COPD, emphysema or chronic bronchitis.

Where COPD is most common

COPD was more common in southeastern and Appalachian states, whatever people's smoking status.

The strong link between a state's smoking rate and its COPD rate was expected among current and former smokers. That the same link appeared among people who had never smoked suggests secondhand smoke as a possible cause. Of the states with the most COPD among never-smokers, only New Jersey banned smoking in private workplaces, restaurants and bars at the end of 2017; the rest had no smoke-free laws, or laws covering only one or two of those places.

Who has COPD

COPD was more common among:

• women (6.8%) than men (5.5%);
• older adults — 12.8% at 65 and older, against 2.7% at 18–44;
• American Indians and Alaska Natives (11.9%);
• people with less education — 10.4% without a high school diploma, against 2.7% of college graduates;
• people in more rural counties — 8.5% in the most rural, 4.8% in large city centers;
• people who had ever had asthma (19.5%, against 4.1%);
• people who were underweight (13.6%) or obese (8.1%);
• people with no leisure-time physical activity (9.6%, against 4.8%);
• people with other chronic conditions — 34.4% of those with four or more.

The same patterns held among people who had never smoked. Besides secondhand smoke, COPD in nonsmokers can come from exposures at work and in the environment, and from chronic asthma. Secondhand smoke in childhood or adulthood has been linked to a higher risk of dying of COPD, although the 2006 Surgeon General's report found the evidence suggestive rather than proof of cause.

What would help

• For everyone: higher tobacco prices, mass-media campaigns, comprehensive smoke-free laws and easy access to proven ways of quitting. Smoke-free laws protect nonsmokers, encourage smoke-free homes and cars, and cut smoking by helping people quit and keeping others from starting.
• For clinicians: ask every patient about tobacco at every visit and offer counseling and FDA-approved medicines to help quit — but remember that not all COPD comes from smoking, and use spirometry to diagnose patients with symptoms whatever their smoking history.

Limits

COPD and smoking were self-reported; doctors may diagnose COPD more readily where smoking is common; the survey is a snapshot and cannot show cause; e-cigarettes, secondhand smoke, air pollution and past respiratory infections were not measured; people in nursing homes, prisons and similar facilities were not surveyed; and state response rates were fairly low (median 45.9%).

Sources

Based on "Chronic Obstructive Pulmonary Disease and Smoking Status — United States, 2017," by Anne G. Wheaton and colleagues (CDC; National Heart, Lung, and Blood Institute), Morbidity and Mortality Weekly Report, Centers for Disease Control and Prevention; a work of the United States government in the public domain.