Kevin, M.D. - Medical Weblog

Are these the "top 10 medical tests you need"?
Should you listen to a financial magazine for medical advice? Let's look at the tests that Forbes recommends. When reading this, I make reference to the USPSTF Strength of Recommendation Ratings:

1) Blood pressure screening
Agreed. This is a class A USPSTF recommendation.

2) C-reactive protein
Still not enough data to support general screening. There are some organizations that do recommend CRP screening. However, there are a couple of concerning issues:
i) CRP is not specific enough. Most inflammatory disorders cause CRP to rise.
ii) There is no therapy targeted to CRP, and there is insufficient data supporting that lowering CRP alone leads to a decrease in cardiovascular mortality.

At this time, I do not routinely order a CRP because of these reasons.

3) Colonoscopy
Agreed. Recommended once every 10 years after the age of 50, or after the age of 40 if you are at high risk for colon cancer.

4) CYP450 test
Not typically tested for. Here is what Forbes says:

Enzymes that encode CYP450 genes--or genes found primarily in the liver, where we metabolize drugs and other foreign substances that enter the body - impact the ability of prescription drugs to penetrate the bloodstream properly. That means that the efficacy of a drug depends upon the availability of these enzymes. The CYP450 test, developed by Indianapolis, Ind.-based Roche Diagnostics, measures the enzyme levels so that doctors can find the right dosage for your body and see if you have immunity to a particular drug. Recently cleared by the Food and Drug Administration, this test is somewhat pricey, ringing in at about $500.

A head scratcher. I've never ordered this test, and it hasn't even been studied by the USPSTF.

5) Diabetes
Screening in adults with hypertension or hyperlipidemia is a class B USPSTF recommendation. Routinely screening in healthy adults is inconclusive, but the American Diabetes Association recommends routine screening in everybody after the age of 45. I use the fasting sugar test to screen.

6) Lipid profile
Screening for cholesterol is important - recommended after the age of 35 in men, 45 in women (earlier if there are other cardiac risk factors). The question is how much to screen for. Forbes recommends the 19-metric cholesterol scan by Atherotech, which is clearly overkill.

The only thing that is recommended is a total cholesterol and HDL (a class B USPSTF recommendation). At the very most, I do a complete lipid panel (showing the total cholesterol, HDL, LDL and triglycerides) - but there is no clear data supporting this.

7) Pap smear
Agreed without question.

8) PSA screening
There is controversy regarding the PSA, as there is no clear data supporting this practice. I do it annually in men over the age of 50 because the legal risks of not doing it is too great. Call it defensive screening.

9) Skin cancer screening
Again, the data is inconclusive.

10) Stress test
This is generally not recommended in healthy, asymptomatic adults. In fact, the USPSTF gives it a class D recommendation:

The U.S. Preventive Services Task Force (USPSTF) recommends against routine screening with resting electrocardiography (ECG), exercise treadmill test (ETT), or electron-beam computerized tomography (EBCT) scanning for coronary calcium for either the presence of severe coronary artery stenosis (CAS) or the prediction of coronary heart disease (CHD) events in adults at low risk for CHD events.

Rationale: The USPSTF found at least fair evidence that ECG or ETT can detect some asymptomatic adults at increased risk for CHD events independent of conventional CHD risk factors (go to Clinical Considerations), and that ETT can detect severe CAS in a small number of asymptomatic adults. Similar evidence for EBCT is limited. In the absence of evidence that such detection by ECG, ETT, or EBCT among adults at low risk for CHD events ultimately results in improved health outcomes, and because false-positive tests are likely to cause harm, including unnecessary invasive procedures, over-treatment, and labeling, the USPSTF concluded that the potential harms of routine screening for CHD in this population exceed the potential benefits.

So, what to make of this? Predictably, the tests recommended are generally overkill, without the support of any evidence. Remember, when it comes to screening tests, more is not better. Articles like this sometimes can be a disservice by asking patients to push for tests that they do not need.

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