The Big Picture
Health screening tests save lives, but they aren’t all without risk. Which ones do you need?
In 2010, an estimated 15,435 Georgians died from cancer; 15,987 died from heart disease; and almost 3,762 died from stroke, one of the highest rates in the United States.
These and many other common conditions can be treated early, and some even prevented, thanks to screening tests available in most hospitals or doctors’ offices.
“Basic screenings for adults are essentially the first step in health promotion and disease prevention,” says Tisha Titus, M.D., director of case management and work capacity for Federal Occupational Health. “We are looking for early disease that hasn’t made itself known yet. We are trying to pick it up before people have symptoms.”
Which screenings should you have when? The answer is not always cut and dried, says Duane Moores, M.D., a hematology/oncology specialist in Brunswick. “When I started practicing 20 years ago, it used to be you are going to get your mammogram at age 40 and boom that was it. The recommendations were nice and clear.”
Today, numerous professional, volunteer and federal government organizations – the American Cancer Society, American Heart Association, American College of Gastroenterology, the United States Preventive Services Task Force (USPSTF), to name a few – publish guidelines for adult health screenings. The guidelines are generally in agreement, but not always. For example, the American Cancer Society recommends yearly mammograms for women starting at age 40, while USPSTF, an independent group of national experts in prevention and evidence-based medicine, recommends mammograms every other year beginning at age 50.
So which guidelines do you follow? The answer may be different for different people. “The catch is when large organizations put out recommendations for screening, they are screening for the general population,” says Dr. Titus, who is based in Atlanta and previously served as the only dedicated preventive medicine specialist with the Atlanta VA. “There are certain subsets of the population where that screening needs to be enhanced. For most of the screening guidelines that have been put out by the U.S. Preventive Services Task Force, there is a caveat that says ‘based on the needs of the patient,’ the special circumstances.”
Such guidelines are intended to curb over-testing, which is not completely harmless. A prime example is prostate-specific antigen (PSA) screening, a blood test that detects levels of a protein that may indicate the presence of prostate tumors. The USPSTF now recommends against routine PSA tests because it causes too much unnecessary harm, including pain, fever, bleeding, infection and problems urinating resulting from biopsies, as well as incontinence and impotence associated with the treatment of tumors that would otherwise not have caused harm.
But even traditional X-rays or CT scans emit radiation, and simple needle sticks can have their risks, says Dr. Titus. “The biggest risk is that every positive result requires follow up, which carries its own risks,” she says. These include the obvious medical risks from a follow-up procedure such as a biopsy to the less obvious, but still significant mental stress of going through additional testing and waiting for results. “So there is a strong risk benefit analysis that has to be done to be sure that we are saving the lives without causing undue harm.”
If you believe that you need a screening, speak up, she says. “We want patients to be very active and engaged in their care, so if they feel very strongly that they need a screening test they need to discuss that with their physician.”
Here’s what you need to know about some of the most common screening tests:
How it’s done: While a woman is standing, a machine compresses the breast, so that X-ray images can be taken. Screening mammograms usually involve two images of each breast.
What it shows: A mammogram makes it possible to see tumors in the breast that cannot be felt. Screening mammograms may also reveal small deposits of calcium that could indicate the presence of cancer.
Who should have it and when: The American Cancer Society recommends yearly mammograms starting at age 40; the USPSTF recommends mammograms every other year beginning at age 50. For his own patients and family members, Dr. Moores would recommend starting at age 40. “I know for a fact that the only way many of my patients knew that they had cancer was they got a mam-mogram,” he says. For women with a family history of breast cancer, mammograms should start even earlier – 10 years before the age of the relative at first diagnosis, says Dr. Moores. For example, if your mother was diagnosed with breast cancer at 45 you should begin mammograms at 35.
What else you should consider: Wherever you live in Georgia, mammograms should be available and affordable. Most health insurance covers the full price of mammograms; for the uninsured, there are programs that offer the tests at reduced rates or for free. Mammography is available at most hospitals – even small, rural ones, says Dr. Moores. Some hospitals have mobile units that make mammograms available in grocery store parking lots and other convenient locations. Women who have more than one immediate family member with breast cancer should speak to their doctors about an MRI, a more sensitive screening for breast changes, he says.
How it’s done: While the patient is sedated, a lighted tube and camera are inserted through the anus to examine the entire colon.
What it shows: A colonoscopy allows the doctor to see any abnormalities in the colon, including small growths called polyps, which could be a precursor to colon cancer. Any suspicious polyps can be removed during the colonoscopy and biopsied.
Who should have it and when: Most organizations, in-cluding the American Cancer Society and American College of Gastroenterology, recommend a first colonoscopy at age 50. “Colon cancers grow so slowly that if you find nothing, you don’t need another one for 10 years,” says Dr. Moores. If the test reveals the presence of polyps, more frequent tests are recommended. If you have a history of colon cancer in your immediate family, you should have a colonoscopy 10 years before the age of the relative at first diagnosis. For example, if your brother was diagnosed with colon cancer at 53 and your father was diagnosed at 50, you should begin colonoscopy at 40.
What else you should consider: Many people find the preparation for colonoscopy – cleansing with strong laxatives – more unpleasant than the procedure itself. Most medical centers offer colon-oscopy. Typically it is performed by a gastroenterologist, but some primary care physicians perform them as well. The procedure is covered by many insurance plans.
CT of the Lungs
How it’s done: The only proven screen-ing test for lung cancer uses low-dose computed tomography (LDCT) to scan the lungs.
What it shows: CT scans, which are noninvasive and use just a small amount of radiation, can show early cancerous changes in the lung tissue.
Who should have it and when: The National Comprehensive Cancer Net-work (NCCN) recommends the test for people between the ages of 55 and 74 who have a “30-pack history” of smoking, defined as a pack a day for 30 years or the equivalent (such as two packs a day for 15 years) regardless of whether they are currently smokers. The test should be given at least three times with a year between tests.
What else you should consider: Studies have shown that CT scans on high-risk patients can improve mortality from 20 to 25 percent, says Dr. Moores. Chest X-rays, which have also been used to screen for lung cancer, have not proven beneficial, says Dr. Moores. CT scans may not be available in smaller towns and insurance may not cover the cost, which can be as high as $400 or more per test. If you think you might be interested, speak with your doctor.
How it’s done: The Pap smear, a screening test for cervical cancer, involves placing a speculum inside the vagina, then using a small tool to scrape cells from the cervix (the lower part of the uterus that opens to the vagina), which are then examined under a microscope.
What it shows: The test allows doctors to check for cancerous or precancerous cells, which if treated can actually lead to the prevention of cancer. It can also detect some sexually transmitted diseases.
Who should have it and when: The American Cancer Society recommends women have Pap smears every two years beginning at age 21, or earlier if they are sexually active. After age 30, women can reduce the frequency of Pap smears to once every three years, after three consecutive normal tests.
What else you should consider: A highly treatable form of cancer, cervical cancer can be deadly if not detected and treated, so recommended screenings are important. Almost any doctor can perform a Pap smear, and the procedure is covered by most insurance companies. In many cases it is performed along with a screening test for the human papilloma virus (HPV), a sexually transmitted virus that can lead to cervical cancer decades after infection. A recent study suggests that Pap smears may help detect ovarian cancer.
Blood Pressure Screening
How it’s done: A cuff is placed around the upper arm and is inflated so that it briefly cuts off the blood flow and is then slowly released. The points at which the sound of blood flow resumes and ceases are recorded.
What it shows: The simple test shows the pressure of the blood in the arteries and presents it as two numbers: The higher number, the systolic reading, indicates the pressure of the blood on the arteries when the heart beats and forces the blood through. The lower number, the diastolic reading, shows the pressure in the arteries when the heart rests between beats. High blood pressure results when the arteries are narrowed or hardened by scarring or plaque. A healthy systolic reading is less than 120; a healthy diastolic reading is less than 80.
Who should have it and when: USP-STF recommends blood pressure screen-ing for adults age 18 and older. Because high blood pressure has no symptoms, it’s important to have your blood pressure checked every time you go to the doctor, says Dr. Titus. People who are otherwise healthy should have a blood pressure reading once a year, says Laurence S. Sperling, M.D., founder and director of preventive cardiology at the Emory Clinic in Atlanta. Those at higher risk of high blood pressure – for example people over age 50 with high blood pressure in their family – should probably have one every three to four months, he says.
What else you should consider: In creating its recommendations, the USPSTF found good evidence that treatment of high blood pressure in adults substantially decreases the incidence of cardiovascular events. If you want to keep a closer eye on your own blood pressure, Dr. Titus recommends trying the machines located at most drug stores. They should be as accurate as the results you get in your own doctor’s office, and maybe more accurate if you have a reading when you are at the doctor’s office for an illness or injury, she says. “If I go to the doctor because I have torn my meniscus [cartilage in the knee], I can guarantee my blood pressure is up because I am in pain.”
How it’s done: Screening for high cholesterol requires a small amount of blood, which in many cases is obtained through a finger prick. It is often performed as part as of a lipoprotein profile.
What it shows: A cholesterol screen-ing shows the total level of cholesterol in the blood. A total cholesterol level under 200 mg/dL is desirable. The lipoprotein profile also specifically measures high- density lipoprotein (HDL) cholesterol, or so-called “good” cholesterol; low-density lipoprotein (LDL) cholesterol, often referred to as “bad” cholesterol; and triglycerides, a type of fat in the blood, which is stored in fat cells.
Who should have it and when: The National Cholesterol Education Pro-gram (NCEP), a group of doctors and scientists affiliated with the National Institutes of Health, recommends that all people older than age 20 have lipoprotein profile every five years. NCEP guidelines suggest more frequent testing for people with cardiovascular disease risk factors such as diabetes, high blood pressure, history of smoking or family history of early cardiovascular disease.
What else you should consider: You can have a cholesterol screening at any doctor’s office. Free or low-cost screenings are also offered by many employers and health fairs. High levels of cholesterol can cause plaque to build up and block your arteries, reducing blood flow, which can lead to a heart attack or stroke. Knowing your cholesterol level can allow you to get treatment if necessary before you suffer a serious cardiovascular event such as a heart attack or stroke.
“A lot of heart disease is potentially preventable, and so it is very important that people understand their risk, know their number, understand their family risk and work with their doctor to develop a plan for heart disease prevention,” says Dr. Sperling.
Blood Glucose Levels
How it’s done: Like cholesterol levels, blood glucose levels can be measured using just a small amount of blood.
What it shows: The blood glucose level shows how well your body is able to convert what you eat and drink into glucose for fuel.
“A screen shows where your glucose level falls,” says Katherine Hines, a registered dietician and certified diabetes educator with Health Matters of St. Francis in Columbus. A glucose level of 126 mg/dL or higher after 10 to 12 hours of fasting or a level higher than 200 mg/dL two hours after a meal could mean diabetes. “There is also something called pre-diabetes, a precursor to diabetes,” says Hines.
A test result of 100 mg/dL to 125 mg/dL or higher when fasting, or 140 mg/dL to 199 mg/dL two hours after a meal may mean pre-diabetes.
Who should have it and when: Screening for diabetes depends on age and general health, says Dr. Sperling. Healthy adults without diabetes risk factors should have a fasting blood sugar level test every five years. People with risk factors – including obesity, high blood pressure, sedentary life-style and family history of diabetes – should have the test yearly.
What else you should consider: Blood glucose screening is simple. You can have it done through any doctor’s office. Many employers and some health fairs offer free or low-cost screenings. If diabetes is detected during the pre-diabetes stage, it may be possible to prevent or delay the development of the disease through diet, exercise and weight loss, says Hines. Undiagnosed diabetes can lead to a wide range of health problems, including damage to the nerves, kidneys and eyes and an increased risk of a heart attack. Routine screening allows for early detection and treatment.