One of the accomplishments of modern medicine is our ability to screen for common diseases. Whether we are monitoring blood pressure as a screen for cardiovascular disease or getting a colonoscopy to screen for colon cancer, we are faced with many opportunities to be screened for disease. Many of my patients as well as those in the medical community itself are beginning to ask questions about the appropriateness of all this screening. So my goal for this article is to review a handful of screening tests and help you to consider whether they are of value to you or not.
First let me define a screening test. This is a test designed to detect a disease in people who do not have any signs or symptoms of the disease. For the most part it is not a diagnostic test in and of itself. For example high cholesterol does not mean you have cardiovascular disease but may warrant further testing to rule out other signs of the disease. Whereas a biopsy done during a colonoscopy may indeed produce a diagnosis.
Cardiovascular disease…this disease remains the number one killer worldwide. We have developed some fairly inexpensive, non-invasive testing for this disease including: blood pressure, BMI (body mass index=weight in pounds x 703/(height in inches)²), ECG, Stress Test (aka treadmill test) and the following blood tests: cholesterol panel, C-Reactive protein, and homocysteine. There are of course more specific imaging tests like CT and MRI when increased suspicion based on the more basic screening tests warrants them. Some of these screens are low cost and minimally invasive which are indicated for everyone like blood pressure, BMI and some blood testing. Other more comprehensive testing is more costly and likely reserved for those at greater risk. Another group who is at a much higher risk for cardiovascular disease are those with Diabetes. And screening for Diabetes is extremely routine, non-invasive and low cost. The simple measurements of BMI and WHR (waist hip ratio) can be used as a preliminary marker for further testing. Routine blood work to evaluate fasting blood glucose and insulin as well as a more long-term view of blood sugar maintenance with a HgA1c (hemoglobin A1c) can all be of value. Making this diagnosis with these simple tests can set a Diabetic or pre-diabetic on a treatment protocol and reduce long-term disease risk significantly.
Cancer…Cancer is more complex to screen for as it is a disease with many types and locations. Therefore more and more screening tests continue to emerge as we continue to understand cancer in greater depth. Recommendations continue to change as these tests improve; and another factor which I believe more indirectly affects recommendations is the cost of the tools or machines used to detect cancers. Diagnosing cancer is certainly not my specialty so I will cover a few basic screens I am asked about, and utilize most frequently. First is the Pap smear. This is a screen of the cervical cells within the vagina. Abnormal results indicate a change in the cells which may or may not be cancerous. This is one of those true screens and further testing with a procedure called a colposcopy is necessary to determine the diagnosis. In the grand scheme of cancers, cervical cancer is relatively inexpensive to diagnose and treat AND the treatments are extremely effective…so get your pap smears! For men the equivalent would be a prostate exam and PSA (prostatic specific antigen) blood test. Both the exam and blood test are screening only and relatively inexpensive. Many practitioners skip the exam portion and just do the PSA, but I consider that a mistake. From a practitioners’ point of view when you couple a blood test with a hands on exam there is much more information to work with rather than just a number. Pap smears are indicated in women in their early to mid-reproductive years whereas prostate exams are indicated in men in their mid to elderly years. For both sexes don’t forget a good skin check to screen for skin cancers while you have the attention of your physician!
Next the Mammogram…I would say this is one of THREE screens necessary for breast cancer; the other two being regular self-exams and yearly exams with your clinician. Mammogram has lots of controversy…I could likely do a whole article just on this, but for this article it is the screening test of choice. Again like the pap smear, mammograms can pick up abnormalities but are not diagnostic. Follow up testing likely involves needle biopsies, lump removals, lymph node removals, etc. to reach a conclusive diagnosis. There are many nuances and decisions to breast cancer diagnosis and treatment and clearly the costs are high. Finally the Colonoscopy. This is the most invasive and most expensive of the cancer screens covered here. This is basically a look and see procedure which, if an abnormality is found and biopsied, can lead to a diagnosis. Again a screening test reaching higher levels of controversy due to global recommendations for screening in adults 50 or over. This is a change from previous recommendations which reserved this screen for those with symptoms or strong family or personal risk factor history only.
Screening for disease is a recommendation, a choice for YOU to make. One point to add is the question what would you do if something is found? OR on the flip side what could you be missing by not screening? The answers are unique to your philosophy on health, the risks (both of the procedure and your personal risk factors), and certainly the cost. These considerations all come into play when deciding whether or not to follow the recommendations. When faced with your next screening test; use your resources wisely, including this 101, to further guide your decision.
DO something you love, BE with someone you love, EAT your vegetables, DRINK clean water, BREATHE deeply, and MOVE your body EVERYDAY!