Some Reference Ranges are Based on comparing results to Misleading formulas.
Last time we reviewed why interpreting your lab may lead you to the wrong diagnosis and treatment. Today we continue our review of each lab panel and why the reference ranges on your lab results may not be the “Healthy Normal Range” that you should compare your results to.
Lab reference ranges are established with a one-size-fits-all mentality, ignoring the numerous variables that influence blood results.
Have you ever tried on a “one-size-fits-all “ANYTHING? Those clothes may fit 20% of the population but for the rest of us, the garment doesn’t fit our width, weight or height! All one-size-fits-all lab reference ranges are much the same.
For example, the standardized “reference ranges” in the US serve as a one-size-fits-all “ideal range” applied to everyone, despite genetic differences, varying latitudes, and the diverse diets that characterize the American multiethnic population. This presents the first problem with using a single range for all people: variations among individuals based on differing genetic needs. The second issue is that the ranges on the lab report indicate the minimum levels necessary for survival, not necessarily the healthiest blood levels for most individuals. Another example of one size doesn’t fit all is the reference range for women’s hormones. A range is displayed for cycling women, but there is no healthy range for menopausal women. Does the range displayed refer to menopausal women with HRT, or menopausal women without HRT to treat their menopausal symptoms? Is the range based on what is healthy, or what is average? We aren’t sure.
Labs don’t ask patients questions that could help interpret lab values. Therefore, they cannot provide a truly diagnostic reference range for any illness. They only consider gender and age, as reference ranges are solely adjusted for these two factors. A doctor must interpret individual lab results alongside a patient’s medical and surgical history, including established diseases, medications, supplements, hormonal treatments, and past lab values. For instance, laboratory companies should offer reference ranges based on whether a patient is menopausal, a woman is undergoing ERT, a man is receiving testosterone, a patient is on thyroid medication, a person is being treated for diabetes, or the diabetic tests are performed to diagnose diabetes.
Some Reference Ranges are Based on comparing results to Misleading formulas
The best example of this issue is the Lipid Panel. Doctors use this panel to determine a person’s risk for heart attacks caused by atherosclerosis. Most doctors don’t know the formula for determining Total Cholesterol. This test doesn’t predict heart disease in most patients, as the formula used to arrive at that number is not indicative of the disease. However, doctors have been advised that when total cholesterol levels are high, a patient should start taking a statin, a drug that reduces blood cholesterol and sometimes lowers the rate of heart attacks in certain individuals, though it is rarely predictive in 50% of the population.
The problem with the lipid panel is twofold: the LDL level indicates future atherosclerosis in only about 50% of the population and is not a specific test for future heart disease risk.
Total cholesterol is even less predictive of heart disease because it stems from a flawed formula.
Doctors interpret a high Total Cholesterol level as an indication that a patient may be at increased risk for heart disease in the future. When I test patients with elevated Total Cholesterol or high levels of LDL using a Cardiac Calcium Scan to measure plaque, only half of them actually produce plaque, and consequently, are not at risk for atherosclerotic heart disease. I believe that the Total Cholesterol number is derived from an inaccurate formula for determining a person’s risk of future heart disease. The Total Cholesterol number is calculated using a flawed equation. The equation is as follows:
LDL + 1/5 Triglycerides+ HDL = Total Cholesterol
Total Cholesterol = LDL (bad cholesterol) + 1/5 Triglycerides (high risk factor) + HDL (good cholesterol)
Let’s examine this formula simply like this: Bad + Bad + Good does not equal Bad. Due to this incorrect formula, thousands, if not millions, of patients have been prescribed statin drugs for a lifetime without justification! Statins carry risks. The list of side effects is extensive and includes muscle deterioration and statin-associated dementia. Unfortunately, most people who experience statin side effects are women. Women tend to have higher HDL levels than men. Additionally, they typically do not have atherosclerotic plaque until menopause and usually do not develop it after menopause if they undergo estrogen replacement therapy!
This gender issue is just one of the problems with laboratory reference ranges that are not adjusted for sex. The total cholesterol values were developed solely from the blood levels of men, who typically have lower HDL levels. Women were excluded from the tests conducted to create this blood panel. For women, I dispel the myth that high total cholesterol predicts heart disease by recommending a Cardiac Calcium Scan to check for plaque. If a woman has no plaque by the age of 50 and is taking estrogen, she is unlikely to develop plaque in the future. I still test them every 2-3 years to ensure that no metabolic changes have altered their risk, but I don’t put much faith in the unreliable cholesterol blood panel.
There is another blood test that has deceptive reference ranges: IGF-1
How about the GH-IGF-1 test, the test for Growth Hormone? IGF-1 is a metabolite of GH that we can measure to determine how much the patient produces. This hormone aids in healing and replenishing aging cells in patients after their growth is complete. The healthy normal range with which I was trained, (150-350 MIU), has been changed to an age-adjusted normal that compares a person to others in her age category who had their blood drawn the previous year. What is wrong with this?
- Growth hormone (GH) decreases with age and contributes to the declining health people experience as they grow older. Similarly, IGF-1 diminishes with age and illness, which means that the “reference range” essentially reflects that you are “average for the sick individuals who visit Quest to have their IGF-1 levels checked. ” IGF-1 levels can be enhanced through weight loss, testosterone replacement, and an increase in muscle mass.
- The current reference range does not indicate health or illness; it merely shows whether you fall within the average for your age group.
- This non-scientific method of determining “health” is widespread in contemporary medicine. By comparing aging individuals to others within the same age group, for hormones that decline with age, based on samples from sick patients who visit a specific lab in the past year, these labs label patients as “healthy” even when they are as ill as other individuals their age who go to that lab! This practice constitutes age discrimination! Regarding hormones, the levels we maintained during our fertile and youthful years correspond to the blood levels indicative of health in all individuals ages.
For example:
People who check their IGF-1 (Growth Hormone) levels and see a low “52 ng/ml” might feel satisfied that they are within the standard range (50-280 ng/ml). However, they may not realize that this range applies to older, unhealthy individuals, not to healthy young ones (150-350 ng/ml). This is just one example of the issues that arise when non-medical individuals, who do not monitor these tests regularly, draw conclusions from the numbers.
Some illnesses require more than one blood test for diagnosis
If you consider only one of the three tests for diabetes or prediabetes (Fasting Blood Sugar, HbA1c, and Insulin), you cannot self-diagnose as diabetic, prediabetic, insulin resistance or healthy. Diabetes is a disease that has coincided with the rising number of obese individuals. Both conditions affect nearly 50% of the American population. Blood tests cannot be interpreted accurately unless a patient has fasted for 12 hours; all three tests should be evaluated. When diagnosing diabetes and insulin resistance, we perform three tests to assess whether a patient has insulin resistance, prediabetes, or diabetes. These tests guide our diagnosis and inform the treatment we provide based on their results.
Fasting insulin is a highly misleading test. Over 15 years ago, a significant study was conducted that was believed to change the reference ranges for fasting insulin. The new range set for normal fasting insulin was less than 10 mIU/ml. By publishing the reference range less than 18 mIU/ml, they miss diagnosing many patients with insulin resistance
HBA1C is a test that gives a value of average blood sugar over three months.
The results are often used alone to determine prediabetes and diabetes; however, considering all three aspects makes the diagnosis and treatment plan more specific for the patient.
FBS (fasting blood sugar) is the third diabetes test. It is generally used as a screening test that prompts the ordering of the other two blood tests; however, some patients exhibit symptoms of diabetes and insulin resistance without having elevated fasting insulin levels.
Many medications can raise diabetic test values, causing a patient to seem diabetic when they are actually experiencing a side effect of the drug. One such medication is Atorvastatin. The solution is not treating diabetes but rather adjusting the medication.
Hormone tests are especially challenging to interpret, Especially when testing free Testosterone in women
Here are the problems with the free Testosterone test itself:
- Women have extremely low levels of free testosterone and testosterone compared to men. I have been informed by Quest that women’s free testosterone levels are not reliable with current methods because they are not always reproducible when a test is conducted twice on the same day. This leads me to believe that hormone levels do not always reflect the actual blood levels of free testosterone and estradiol.
- The levels of testosterone in women are based on menopausal levels of T. Women have long been thought to not produce testosterone, so the “normal” levels are quite low, and 0 used to be considered normal- until one day I managed to persuade a medical director at Quest to increase it to 0.2!
- Women’s testosterone is influenced by their production of E2 and E1, which inactivate free T. Women vary in how their cells respond to testosterone and estradiol.
- Receptor sites and their genetic acceptance of hormones can mean that the same blood level of testosterone in both sexes does not produce the same effects in all patients. Some women (and men) are resistant to E2 and T, or to one of the two. This indicates that the hormone-free T level may be optimal for one woman while being ineffective in alleviating any low T symptoms for another. The latter individual is T resistant, and we currently have no means outside of research labs to determine which women are sensitive and which are resistant. This requires that doctors and NPs look beyond typical reference ranges to effectively manage E2 and T replacement for women.
- Lastly some labs use the total testosterone level through a formula determine the free T. This carries inherent risks of reporting the wrong active level of testosterone.
Total and free testosterone blood levels for men, are derived from results of older men, rather than from the blood levels that indicate health and the levels at which men experience no symptoms. This leads men to believe they are normal, even though they are symptomatic, and they can’t get treatment.
There is no time to discuss the reference ranges for LH, FSH, Estradiol, and Estrone; these topics will be addressed in a future blog. I hope I have encouraged you to review your blood work with your doctor or Nurse Practitioner, and not to act as your own doctor by interpreting your blood tests.
