Obesity and Large Waist Size Increase Risk of COPD

Researchers identify obesity as a risk factor for chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD), is a progressive disease that makes breathing difficult. Also known as emphysema, this chronic condition is known to be the third leading cause of death among Americans. This lung disease is mostly caused by smoking. But in the new study, researchers in Germany and the United States, have identified obesity as another important causative factor for COPD.

They link excessive belly fat and low physical activity to progression of disease in those with COPD.  

In this study the researchers looked at the link between hip and waist circumference, body mass index (BMI) and levels of physical activity to new cases of COPD in a group of U.S. men and women. They evaluated the data of 112,279 people of ages 50-70 who did not have COPD, cancer or heart diseases at the start of the study. During the 10-year follow up period, they noticed that 3,648 people developed COPD.

Women who have a large waist circumference i.e 110 cm or more and 118 cm or more in men, are at 72 percent higher risk of COPD.

"We observed a stronger positive relation with abdominal body fat than with total body fat and COPD," writes Dr. Gundula Behrens, Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany, with coauthors. "In particular, overweight as measured by BMI emerged as a significant predictor of increased risk of COPD only among those with a large waist circumference."

Large waist was noted as a strong predictor for COPS in smokers and as well as non-smokers.

 "Increased local, abdominal and overall fat depots increase local and systemic inflammation, thus potentially stimulating COPD-related processes in the lung," write the authors.

Those with large hip circumference and those who remained physically active at least 5 times a week had a 29 percent reduced chance of developing COPD.

Underweight people had 56 percent elevated risk of COPD, mostly due to malnutrition, reduced muscle mass leading to increased COPD susceptibility and progression through inflammatory processes and impaired lung repair capacity.

"Our findings suggest that next to smoking cessation and the prevention of smoking initiation, meeting guidelines for body weight, body shape and physical activity level may represent important individual and public health opportunities to decrease the risk of COPD. Physicians should encourage their patients to adhere to these guidelines as a means of preventing chronic diseases in general and possibly COPD in particular," state the authors.

The study was published in the Canadian Medical Association Journal.