When it comes to health, what numbers do most of us REALLY need to know? Entry 12 – 2010


In a 2009 study of a heart disease risk, low-income women were screened at baseline for hypertension, high cholesterol, and diabetes (1). Participants were given their biometric “numbers” by their physicians at the time of screening. One year later, researchers asked the women about their risk status. A majority of high-risk women reported that they had never been told they were at risk!

  • 66% of those with hypertension reported never having been told they were hypertensive.
  • 54% of those with high blood glucose reported never having been told they had high blood sugar.
  • 45% of those with high cholesterol reported never having been told it was high.

According to the researchers, the study protocol required providers to inform the high-risk woman verbally about the result and confirm it in writing. Certain factors made women more likely to report never being told. Those who had lower incomes, were of older age, and were not Caucasian were most likely to say they were never told. In other words, those who were more likely to be at risk were least likely to have understood or remembered being told that they were.

An unusual case?
We may be tempted to dismiss such results as particular to a lower-income, less-educated group and unimportant for those of us who work with younger, informed, educated employees. Not so fast. Apparently, we can expect ten to forty percent of patients to report not having been told of a condition, when they had been (2, 3). Plus, even in populations that remember that they have hypertension, many don’t know their current blood pressure numbers, nor what they should be (4, 5). Further, when told what they can do about their blood pressure, patients are much more likely to “remember” that they were prescribed medication versus remembering they should change their diet or exercise.

Do we over-measure? What about “know your numbers”?
“Know your numbers!” is a popular expression in wellness programs, encouraging participants to get their regular health screenings. The logic is that if a person becomes aware of his health risks (such as high cholesterol or high blood pressure), it will increase the likelihood that he can control the problem. Once high-risk people are identified with an actual number, we hope it makes their risk more tangible. Plus, programs can reach out to newly-identified people who can get counseling and treatment from doctors. In theory, “know your numbers” leads to “healthy numbers,” which means a healthier person. But that assumes numbers actually mean something. What if the actual numbers have less of an impact than is traditionally assumed?

What numbers should we know?
Before thinking through the implications of so much “forgetting,” I went back to remind myself about general recommendations for screening. The US Preventive Services Task Force, the national agency that reviews evidence about tests and treatments, recommends adults get screened for blood pressure every other year, or more often if their levels are elevated. They do not recommend testing for high cholesterol until age 35 for men and age 45 for women, unless there are other risk factors. For those with healthy values, one test every five years may be sufficient. And the task force does not recommend general screening for glucose for any adult unless blood pressure is high or other risk factors exist. Then, for those whose readings are low-risk, retesting should occur once every 3 years (6, 7).

So in a nut shell: few of us need to be screened until a little later in life unless we have other risks (e.g., the obvious: overweight, not exercising, smoking, or family history of a disease), and we don’t need to be rescreened very often unless other things come up. It makes me realize that perhaps we have over-measured for reasons other than health—to prove the need for programs or measure their impact, for example—not because the numbers are that more helpful than obvious things we already know. In a world where we have limited resources, are the dollars we spend on screening worth the investments?

Perhaps we over-think and over-measure health in ways that add unnecessary expense and little value. For the most part, one can tell if health gets in the way of people’s day-to-day lives by knowing a few things: do they usually get a good night’s sleep, are they generally happy with life, and are they able to do most of the things they need to do on a daily basis? One can also get a sense if they are heading for health problems in the future with simple information: if they smoke, if they abuse substances, if they get regular exercise, and about how many pounds away from a normal weight they are. Certainly there are other factors, but mostly health is common sense.

Not only do most of us know what make us unhealthy, by default we also know what can help us get well. All of the most common illnesses become less likely if we adopt basic healthy habits. Again, this depends on common sense. While at a certain age and under certain conditions screening makes sense, maybe the only numbers most of us need are: packs of cigarettes smoked, miles walked, and extra pounds on our bodies.

The cost of knowing numbers that aren’t remembered
I have often worried about the excess money spent on repeated screening for relatively healthy people in corporate programs. Now that I realize that many screening results are disregarded or misunderstood, I worry even more. If we screen virtually everyone, then find the one in three who has a high reading, a third or more won’t remember, and another third go to a doctor and only remember to take pills rather than exercise or eat better…that only leaves one in nine who heard and remembered that he needs to improve his health habits. At a conservative cost of $40 per screening, it costs $360 per person (the one of nine who had risk, heard the news, and remembered) to find out that healthier habits would help them, which they most likely knew already.

If the numbers don’t mean anything, are they worth knowing? One wonders if the Cleveland Clinic approach would make numbers matter more. The Cleveland Clinic does not hire people if they smoke (they are tested for nicotine) and charge morbidly obese employees a lot more for health insurance if they do not attain a healthier weight (8). It is likely those employees know the important number (how many pounds they have to lose), whether they remember their cholesterol level or not.

Why this matters: The value of screening can often be overstated or expressed in terms of the few people whose dangerous values were detected ‘in the nick of time.’ It is important to remember that screening and prevention are not the same thing. If we follow the evidence, screening has a place in overall care for the right people, in the right circumstances. For the rest of us, we probably know what habits would improve our health and can decide to do so without being assigned a clinical value, which we might forget anyway. There are health and financial consequences to being unhealthy. However there are also financial consequences to unnecessary testing, but that seems to be a number we rarely hear about.


1. Khavjou OA, Finkelstein EA, Farris R, Will JC: Recall of three heart disease risk factor diagnoses among low-income women. J Womens Health (Larchmt) 2009;18:667-75.19405860

2. Croyle RT, Loftus EF, Barger SD, Sun YC, Hart M, Gettig J: How well do people recall risk factor test results? Accuracy and bias among cholesterol screening participants. Health Psychol 2006;25 :425-32.16719615

3. Martin LM, Leff M, Calonge N, Garrett C, Nelson DE: Validation of self-reported chronic conditions and health services in a managed care population. Am J Prev Med 2000;18:215-8.10722987

4. Oliveria SA, Chen RS, McCarthy BD, Davis CC, Hill MN: Hypertension knowledge, awareness, and attitudes in a hypertensive population. J Gen Intern Med 2005;20:219-25.15836524

5. Kravitz RL, Hays RD, Sherbourne CD, et al: Recall of recommendations and adherence to advice among patients with chronic medical conditions. Arch Intern Med 1993;153:1869-78.8250648

6. U.S. Preventive Services Task Force.Screening for High Blood Pressure. Dec, 2007;  (accessed Nov 12, 2010).

7. U.S. Preventive Services Task Force.Screening for Lipid Disorders in Adults . Jun, 2008; (accessed Nov 12, 2010).

8. Singer, S.Cleveland Clinic pays its employees to get, stay healthy. Jan. 2, 2010; (accessed Nov 12, 2010).


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