I appreciate Dr Einstein's interest in my editorial “First Physical” and agree that it is difficult to estimate the exact cancer risk for any particular CT scan. Indeed, for a routine chest CT scan without contrast, the radiation dose when measured at 4 San Francisco Bay area institutions ranged from 1.7 to 24 mSv, with a median dose of 8.2 mSV.1 I also agree that a coronary calcium scan done using EBCT would likely have a lower radiation dose than one done using newer technology. However, no risk, even a small one, can be justified for a test with no known benefit, such as a coronary calcium scan. While it is true that the risk of cancer would be beyond the end of the Obama presidency, it is also true that there is no benefit that will accrue during the presidency (or afterwards) from a coronary calcium scan. Also, a false-positive result could have resulted in the President being subjected to an invasive procedure such as coronary angiography, with additional harms, including further radiation, the need for sedation for several hours rendering him incapable of performing his duties, and a small but finite risk of complications, including death. Dr Einstein's suggestion that starting a lipid-lowering medication based on coronary calcium score is “more likely to be beneficial than harmful” is pure speculation. There is no data showing any mortality benefit of lowering lipid levels for primary prevention, particularly in low-risk men, such as the President, and a coronary calcium scan would not change that.
President Obama’s Coronary Calcium Scan—Reply. Arch Intern Med. 2010;170(13):1175-1176. doi:10.1001/archinternmed.2010.213