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Breathe free

Chronic lung disease is our nation's No. 4 killer. And 80% to 90% of those deaths come from one cause: smoking.

There's an old Scottish proverb that goes something like this: "We'll never know the worth of water till the well goes dry." Unfortunately, for millions of Americans, chronic obstructive pulmonary disease (COPD) has caused their lungs' wells to "go dry." For a doctor, few things are as difficult to watch as someone suffering from severe obstructive lung disease.

COPD encompasses several lung ailments; all are characterized by the obstruction of airflow. The two primary types of COPD are emphysema and chronic bronchitis. More than 11 million people have the disease, according to the American Lung Association.

As the fourth leading cause of death after heart disease, cancer and stroke, COPD is no trivial problem for our nation. Still, COPD is preventable. That's because 80% to 90% of all COPD deaths result from just one cause: smoking.

As a physician, I worry that smokers think we harp on them about smoking as though it were a character flaw, not a health risk. That's not the case: It's simply that cigarette smoking is a primary contributor to so many ailments, including COPD, which occurs only after years of habitual smoking. Young smokers don't understand this. They feel great. They feel bulletproof. In short, they feel like they're healthy. They don't realize what life would be like without the ability to breathe normally. If they did, they'd never light that first cigarette, pipe or cigar.

The best way to prevent COPD is never to smoke. But if you're a smoker -- even if you already have impaired airflow -- you can help put the brakes on continued decline in lung function by quitting smoking. Talk to your doctor. Make the commitment to stop now, before your lungs' wells go dry.

Tedd Mitchell, M.D., president and CEO of Dallas' Cooper Clinic, writes HealthSmart every week.