People with pulmonary health problems may face a higher risk of developing diabetes, according to a government study released late last year.1
Lung Disease Link to Diabetes
In findings that echoed previous research, doctors at the Centers for Disease Control and Prevention (CDC) found that the odds of developing diabetes increased as certain measures of lung function decreased.
Earl Ford, MD, and David Mannino, MD, of the National Center for Chronic Disease Prevention and the National Center for Environmental Health, respectively, pulled data from the National Health and Nutrition Examination Survey Epidemiologic Follow-Up Study to assess the risk of diabetes relative to lung function. In all, the study included information on more than 4,800 men and women aged 25 to 74 who had an initial interview and lung tests, including spirometry—a measure of the volume and flow of air—between 1971 and 1975. Each individual had been followed for nearly 20 years afterward.
During the follow-up period, Ford and Mannino learned 443 people became diabetic, based on verbal reporting, hospitalization or death certificate data.
An Inverse Relationship
When comparing measures of lung function to the incidence of diabetes in this group of patients, Ford and Mannino found that as measures of two lung tests known as forced expiratory volume (FEV) and forced vital capacity (FVC) decreased, the odds of contracting diabetes surged.
Forced expiratory volume measures the total amount of air that can be exhaled in a given number of seconds. Forced vital capacity measures the flow of air in a given exhalation. This is done by using a spirometer, an instrument into which a patient is asked to exhale forcefully for 6 seconds or more after inhaling as much air as possible.2
"Obstructive lung disease was not significantly associated with the incidence of diabetes, but restrictive lung disease was," wrote the two researchers. "The association did not differ significantly by smoking status."
Different Illnesses
Obstructive lung disease and restrictive lung disease are two distinct pathologies. Restrictive lung disease is caused by a reduction in the amount of air that your lungs can hold. They become stiff, which limits their ability to expand when you breathe in. In contrast, obstructive lung disease is due to a decrease in the amount of air that you can exhale from your lungs caused by narrowing or blocking of airways. Restrictive lung disease includes ailments like sarcoidosis and pulmonary fibrosis.3
In contrast, chronic obstructive lung disease, also known as COPD, is a general term that includes diseases like emphysema and chronic bronchitis. It is characterized by extensive lung damage, which makes it harder to breathe. It is the fourth most common cause of death in the United States and is blamed on cigarette smoking in most cases.4
"Although several prospective studies have found that impaired pulmonary function may increase the risk for developing diabetes, additional research is needed to better understand these relationships and their possible implications," the two physicians in this study wrote.
1. Ford ES, Mannino DM. Prospective association between lung function and the incidence of diabetes. Diabetes Care 2004 Dec;27(12):2966-70.
2. National Lung Health Education Program (NLHEP). Spirometry. Available at: http://www.nlhep.org/spirom1.html. Accessed April 28, 2005.
3. Mayo Foundation for Medical Education and Research. Restrictive vs. Obstructive Lung Disease: What's the Difference? Available at: http://www.mayoclinic.com/invoke.cfm?id=AN00759. Accessed April 28, 2005.
4. National Heart, Lung and Blood Institute. What is Chronic Obstructive Pulmonary Disease (COPD)? Available at: http://www.nhlbi.nih.gov/health/dci/Diseases/Copd/Copd_WhatIs.html. Accessed April 28, 2005.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
