COPD INCIDENCE

COPD is the most common serious lung disease in the United States. Over the last few decades, there has been an increase in the percentage of Americans with COPD. Currently, 16 million adults in the United States have a diagnosis of COPD, and an equal number of Americans with COPD may still be undiagnosed. Three million people a year worldwide die from COPD. Among people with COPD, most people have a combination of the chronic bronchitis form with the emphysematous form (NIH, 2021a).

Age of Onset

Eighty percent of deaths of patients with COPD are secondary to excessive smoking, although 25% of those with COPD have never smoked (CDC, 2021a). The characteristics of the population of people with COPD—such as chronic cough, shortness of breath, limited energy, and sputum production—are the same as the characteristics of the population of people who have been long-time smokers.

COPD is most common in older people because symptomatic COPD usually takes more than 20 pack-years of smoking to develop. A lower percentage of adults ages 40–64 years have had any lung obstruction compared with adults ages 65 years or older. Approximately 15% of adult Americans are smokers (CDC, 2021b).

The current generation of older adults has done a record-breaking amount of cigarette smoking. Although many older Americans have stopped smoking, even those who quit can develop symptoms of COPD and suffer a greater-than-normal decline in their breathing ability late in life. Physiologic changes in older adults with COPD, including reduced lean muscle mass and decreased respiratory muscle strength, cause an increased disease burden, including more frequent exacerbations, more dyspnea, and lower exercise tolerance. The higher incidence of comorbidities, especially cardiac, may prove a more challenging plan of treatment, for instance, due to potential drug-drug interactions. Impaired cognition, arthritis, impaired vision and hearing, and depression will also affect disease progression and prognosis (Harding et al., 2020).

One out of 13 Americans under 17 years of age has tried cigarette smoking. At the current rate of smoking in those under age 18, 8.6 million will die from smoking-related diseases. Among high school students surveyed in 2020, 19.6% self-admitted to smoking e-cigarettes and 4.6% self-admitted to smoking traditional cigarettes (CDC, 2020a). (See below for more information about e-cigarettes, or “vaping.”)

Gender

Women are diagnosed with COPD later than men, causing the disease to be more advanced and therefore any treatment to be less effective (CDC, 2021c). Women have an increased susceptibility to COPD caused by smoking, likely due to smaller lungs, smaller airways, and lower elastic recoil. Women with COPD experience a worse quality of life, more acute exacerbations, more dyspnea, but a better response to oxygen therapy than men (Harding et al., 2020).

Race

The prevalence of COPD follows the history of the level of smoking in a population. In the United States, higher rates of COPD are found among those who have had the highest levels of smoking. The majority of all people with COPD are current or former smokers. American Indians/Alaskan Natives and multiracial non-Hispanics are more likely than other ethnic groups to have COPD (CDC, 2021c).

Mortality Rates

COPD is the fourth leading cause of death in the United States. The increased level of smoking by women over the past 30 years is causing women’s death rates from COPD to rise, while the death rates from COPD is dropping for men. The greater mortality in women may also be due to their smaller lungs, the contribution of estrogen to the severity of lung disease in women, and misdiagnosis in women (Harding et al., 2020).