July 16, 2018
Home Medical Tests: Which Can You Trust?

Home Medical Tests: Which Can You Trust?

by Tuan C. Nguyen  

When the first home pregnancy test finally hit store shelves in 1977, it was so remarkably innovative that the company touted the product as the “private little revolution any woman can easily buy at her drugstore.” Fast-forward a few decades, and the idea of do-it-yourself health testing has blossomed into a rapidly growing marketplace with offerings for a wide range of health concerns, from sexually transmitted diseases to high cholesterol.

A small handful of home tests have come to play an important part in the management and treatment of common chronic conditions such as diabetes. But much of what’s available hasn’t proven quite as useful.

With many of these tests, there’s also a risk of users making health decisions based solely on test results that later turn out to be wrong. For instance, trials by Orasure Technologies, maker of a saliva-based home HIV test, reported false negatives about 8 percent of time. A mistaken sense of reassurance can lead to behaviors that put others at risk. At the same time, though, at-home testing offers anonymity for those who want to get results confidentially and may encourage more people who otherwise wouldn’t get tested to do so.

Which home health tests are worth considering, and which should you avoid? Here’s a breakdown of the risks and benefits of some common home health tests available commercially, starting with the more well-established ones that have withstood the test of time.

A word to the wise: Before you buy any home health test, look for versions that are FDA-approved. The agency requires home testing methods to be plausible, fairly accurate, and easy to use.

Recommended home health tests

Blood glucose monitors.Encouraged by doctors and widely available, home blood glucose monitors have come to play an important role in helping patients with diabetes manage their condition. Closely monitoring blood sugar levels, especially for those who have type 1 diabetes, allows patients to tailor their diet, medication, and other aspects of treatment to keep the levels within a normal range.

Glucose meters are simple to use. A finger prick and a drop of blood are all that’s needed. Recent improvements have led to smaller, faster, and more accurate models. The FDA requires home glucose meters to be within 15 percent of results produced in the lab.

Additionally, there are a couple of relatively new choices on the market. Alternative site monitors, for instance, can be used to collect samples from other body areas less painful than the finger, though they also tend to be less accurate. Patients can also opt for a system called continuous glucose testing, in which a sensor implanted beneath the skin takes regular glucose readings and sends them to a wearable monitor, alerting the user to any problematic changes.

Blood pressure monitors. These devices can be very helpful to people trying to manage hypertension, a condition that affects roughly a third of American adults. Regularly tracking blood pressure at home can help patients and doctors make decisions about treatment, such as adjusting dosages or changing medications.

While blood pressure levels are routinely checked during doctor's visits, studies have shown that the average from several readings over a longer period of time offers a closer approximation of a person's actual blood pressure levels.

Automatic arm and wrist monitors are the most popular ways to measure blood pressure at home. While wrist monitors are smaller and more comfortable than ones that attach to the arm, they're also less accurate. Devices that take readings at the fingerare less accurate than both and should be avoided.

Pregnancy tests. During pregnancy, a hormone called human chorionic gonadotropin (hCG) is released by the placenta, with levels typically doubling every 48 to 72 hours during the first couple weeks after conception. Pregnancy tests, both in the lab and at home, check for the presence of hCG.

The difference is that lab tests, which measure hCG levels in samples of blood rather than urine, have a higher level of accuracy and can be used to confirm a pregnancy as early as a week after conception. Still, home pregnancy tests are close to 99 percent accuratewhen used as directed. They are convenient and deliver the result in minutes.

The process is simple and fairly straightforward. A line, a certain color, or a symbol indicates the user is pregnant. For best results, wait about one week after a missed period and perform the test in the morning, when hCG levels are at their peak.

Home health tests that may be worth considering

Cholesterol home tests. Since cholesterol levels don’t fluctuate very much on a day-today basis, there's little impetus for home testing, although the results of these tests can be quite accurate. And even then, doctors consider factors other than your cholesterol level, such as your age and family history, to assess your overall risk of heart disease and determine whether treatment with cholesterol-lowering statin drug is warranted. If you do opt for a home-based test, choose one that provides a lipid profile breakdown of both LDL (bad) and HDL (good) cholesterol rather than just total cholesterol.

HIV home tests. For now, the Home Access HIV-1 Test System and Oraquick In-Home HIV Test are the only FDA-approved options available for at-home HIV testing. Of the two, the HIV-1 Test, which analyzes blood samples, can detect HIV infection earlier and is less likely to result in a false negative. But for a painless process that produces rapid results, the newer Oraquick saliva-based kit is the way to go. For both tests, a positive result must be confirmed with a standard laboratory test.

Home colon cancer screening tests. While a colonoscopy remains the standard way to screen for colon cancer, some patients aren't keen on a less-than-pleasant procedure that involves emptying the colon with laxatives beforehand. As an easier alternative, fecal occult blood tests checks for the presence of invisible traces of blood in stool samples, often a telltale sign of colon cancer. However, blood in the stool can also be caused by hemorrhoids, consumption of red meat, or a host of unrelated conditions. The best test is called the FIT (fecal immunochemical test). It’s more sensitive and specific than other tests and does not require avoiding red meat.

Urinary tract infection (UTI) tests. Test strips that check for high levels of nitrates can be used to identify bacteria in the urine, although a check-in with the doctor is still needed to obtain antibiotics.

Home health tests to skip

Testosterone level tests. Although testosterone levels in men decline as a natural part of aging, even a low level of that hormone generally isn't a problem unless it is accompanied by undesirable symptoms, such as low sexual desire and erectile dysfunction. It's true that abnormally low "T" has been linked to obesity, diabetes, high blood pressure, and erectile dysfunction, but it isn't clear whether those conditions are a cause of low testosterone or the other way around. To check testosterone levels, lab tests using blood samples have long been the gold standard. There are newer, saliva-based home tests, but the evidence thus far isn’t sufficient to suggest they are as reliable as blood tests.

Alzheimer’s screening tests. Early detection of Alzheimer's allows the patient and loved ones to plan for the necessary care as well as other changes ahead. But self-diagnostic screening tests you can take at home should never be substituted for diagnosis by a doctor. The Self-Administered Gerocognitive Exam (SAGE), is a 15-minute pen-and-paper downloadable questionnaire that tests a person’s language, reasoning, problem-solving, and memory. Researchers at Ohio State University who devised the test say it can correctly identify people with mild cognitive and memory problems 80 percent of the time. And it has a small rate of false positives—95 percent of people who donothave cognitive issues have normal scores. But a proper diagnosis of Alzheimer's disease can only be made after a thorough evaluation by a doctor. This typically involves taking a medical history, a neurological exam, brain imaging, and a series of lab tests to rule out other causes. Don't rely on a home test to determine if you or a loved one may be developing Alzheimer's.

Allergies. In 2013, biotech startup ImmuneTech introduced a product called MyAllergyTest, which they claimed to be the first FDA-approved home allergy test. It allowed consumers to test for 10 of the most common allergens. Allergists and doctors were quick to point out some of the flaws of the blood-based method. The test has since been shelved and company is no more, but other tests that rely on a similar approach are still on the market.

Ovulation or fertility tests. Ovulation predictor kits are designed to detect surges in luteinizing hormone that normally takes place about 36 hours before ovulation. In practice, the approach is more akin to an educated guess as ovulation sometimes doesn't occur. Being on fertility treatment also tends to make the tests less reliable.

One of the most popular and widely available fertility tests looks specifically at levels of follicle stimulating hormone, which tends to rise as women approach menopause. However, levels of FSH are known to fluctuate from month to month, and evidence suggests that a newer test designed to gauge levels of anti-Müllerian hormone (AMH) may be a more accurate indicator of a woman's egg count. AMH tests are usually performed at fertility clinics, though there's at least one home-based kit available in the United Kingdom.

Also see Screening Tests: How Old Is Too Old?