What is CLRD?

Chronic lower respiratory disease (CLRD) is used to describe a group of diseases generally consisting of chronic bronchitis, emphysema, and asthma. These diseases affect the lower lung and are characterized by shortness of breath due to airway obstruction. Prior to 1999, CLRD was synonymous with Chronic Obstructive Pulmonary Disease (COPD); however, in 1999, the definition of CLRD was expanded to include asthma. Our Coalition uses CLRD when referring to the complete group of lung diseases (asthma, chronic bronchitis and emphysema), and we use COPD when referring just to chronic bronchitis and emphysema. This is an important distinction, as the epidemiology of asthma differs from that of chronic bronchitis and emphysema.

The Burden of CLRD

Currently in the United States, an estimated 23 million people have asthma and approximately 15 million people have been diagnosed with COPD. However, it is estimated that as many as 50 percent of pulmonary disorders go undiagnosed and therefore untreated. Lung diseases that are undiagnosed, untreated, and/or poorly managed lead to missed days of school and work and preventable emergency room visits and hospitalizations – increasing the impact on the individual in terms of life quality and on society due to higher insurance rates and lost productivity. Factors that contribute to effective management of CLRD include proper diagnosis and access to health care and disease management resources. Unfortunately, limited financial resources, lack of health insurance coverage, geographic isolation, and language barriers impede access to these resources.

CLRD Epidemiology

In the United States, CLRD is the 3rd leading cause of death, behind only cancer and heart disease. In Arizona, while mortality rates for the top two leading causes of death, cancer and heart disease, have been decreasing over the past two decades, death rates from CLRD remain stubbornly persistent. (Figure 1)


In Arizona, deaths due to CLRD vary by race/ethnicity (Figure 2), with age-adjusted death rates highest among Whites. In 2013, according to the Arizona Department of Health Services (ADHS), there were 167 more CLRD deaths in Arizona among women than men, with an average age of death of 77 years.

LUNG TEXTFig2 Age Adjusted