Tuesday, December 03, 2002
Full body scans, I have always felt, are not a good idea. It's nice to see someone backing me up:
Full-body CT scans -- widely promoted in advertisements as a way to give yourself peace of mind -- frequently find harmless abnormalities that lead to invasive, anxiety-producing follow-up tests, researchers say. And they may be a waste of money for patients under 40, who run a low risk of serious disease, the study suggests.
"This got pushed to the public before any of the research was done," said Dr. Giovanna Casola of the University of California at San Diego. "They're saying do it for your peace of mind, do it for your wellness, for your family. Nobody's saying, `Half the time we're going to find things that you're going to worry about,"' sometimes needlessly.
The article goes on to say that 46 percent of all scans done showed abnormalities (this could include some innocuous cyst somewhere or something similar) and that 37 percent of all participants were advised to have follow-up tests! That's a lot! In other words, to use the language of statistics, these tests are quite sensitive but not very specific. Most of their findings turn out to be benign. Also, it's easy for the imaging centers to blithely advise their clients (I refuse to call them "patients") to go back to their primary care doctors to get these abnormalities worked up... they aren't the ones who have to bear the expense of ordering these tests and chasing down all the results. And thus the cost of medical care goes up due to these unnecessary tests, and the cycle continues.
I think that for someone who has a strong family history of coronary artery disease, especially before the age of 50, the high-speed CT scans of the heart are a good idea. This is a high risk population. When you screen a cohort of people for a given disease who are at greater than average risk for getting that disease, the sensitivity and specificity of any test will increase. On the other hand, high speed CT scans of the lung to screen for lung cancer are not as good an idea. Quitting is better. The scans do pick up tumors at a smaller size, but you need to keep getting the scans year after year, even after you quit smoking. The people who continue to smoke and get these scans as a prophylaxis, and I know they're out there because I see them, are kidding themselves.
Rant over for today.