This comes up every day. Everyone’s afraid of the big “C”, and they should be. Smoking increases a person’s risk of dying of lung cancer by about 12-20 times (whatever that means, but it’s significant).
And while cancer may be scary, other diseases are just as bad. Lung cancers attributable to smoking cause about 125K deaths per year (all numbers US). Add in head and neck cancers, and the number goes up to about 133K. Add in cancers with less clear causative associations and we’re up to 160K.
In contrast, there are about 130K cardiovascular deaths yearly attributable to smoking, and about 100K deaths due to lung disease such as emphysema.
So let’s explore the various ways of dying of tobacco poisoning.
Lung cancer sucks—it really sucks. I’ve had two close relatives die of it. I’ve lost friends to it. I’ve lost patients to it. Since it it responsible for about a third of smoking-related deaths, it’s important. It’s the one all my patients are scared of. But there’s still two-thirds left.
For example, COPD—chronic obstructive pulmonary disease. This is a spectrum of diseases that includes emphysema and chronic bronchitis. It good and truly sucks. My father told me that when he was in his medical training, emphysema was the disease that he’d least want to die of (or more properly, live with). The chronic breathlessness, fatigue, and weakness is horrible. Patients often feel they are hungry for air—and there’s very little I can do about it. Emphysema involves irreversible destruction of lung tissue. The lung’s primary duty is gas exchange, and gas exchange is dependent on surface area. Lungs aren’t all that big. If they were simple sacs, their effective surface area would be in the range of a few square feet. The lungs create surface area by having millions of small sacs called “alveoli”, which provide about 100 m2 of active surface area (about a tennis court’s-worth).
The scary thing about this picture of a lung isn’t the black carbon deposits, it’s the large holes containing the black carbon deposits. The alveoli that used to occupy those spaces have broken down, creating large, rather than small sacs, reducing effective surface area significantly. Less surface area = less gas exchange = feeling like you can’t breath—because you can’t. About a third of smoking related deaths are caused by lung diseases such as emphysema. Yuck.