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Self testing: a big future?

Self-testing: A big future?

Self-testing, home testing, do-it-yourself testing--whatever you choose to call it, over-the-counter test kits are the hottest items on the home health care front today. People stepping up to buy everything from glucose monitors to gonorrhea tests are a new breed of consumers, sending an urgent signal to traditional medicine that they want more responsibility for their own medical care.

So far, the medical establishment's reaction to self-tests has been mixed. Most in the profession have accepted home glucose monitoring for diabetics--an option that has been available for almost 50 years--if it is performed under a physician's supervision. However, many of the new diagnostic tests raise very real questions about quality control, impartiality, and liability, as well as more subjective physician concerns, such as loss of control and income.

In a letter to the Food and Drug Administration last October, American Medical Association executive vice president James H. Sammons expressed the association's belief that, "Screening and monitoring testing methodologies hold great potential for indicating aberrations from normal good health that warrant a physician's attention. These testing methodologies hold the promise of earlier, more effective, and less complex medical intervention in the treatment of disease.'

After outlining issues he felt the FDA should address to limit "inaccurate test results, misinterpretation of test results, or failure to follow up properly and in a timely fashion on such results,' Sammons made clear the course that the AMA envisions for self-tests: "The physician community should be designated in the labeling as the source . . . for professional interpretation of test results and directions for acting upon such results. Such labeling should clearly recognize the physician as the individual responsible for provision of proper, necessary medical care.'

The College of American Pathologists has not taken an official position on self-tests, but the subject was on the agenda of a CAP conference on alternative-site testing last April in Atlanta (Washington Report, MLO, May 1986).

Paul Bachner, a member of the CAP's Quality Assurance Service Committee and a regional commissioner for the laboratory accreditation program, was a member of the legal and regulatory affairs working group at the CAP conference. He reports that, "Pathologists are still focused on the issue of laboratory testing being satellited in the generic sense. The home situation makes the connection between the usual sources of training, quality control, and standarization even more tenuous. We all have real concerns about how people will use these tests--whether they will get the appropriate answers in terms of what they're trying to figure out.'

Another participant in the CAP conference, Michael Kafka, who chaired the session on analytical performance criteria, says his group didn't really address the specifics of self-tests. "Home testing is a whole new area. Some form of quality control must be a natural part of the packaging so the patient has some idea whether he has even done the procedure correctly. That falls back on the manufacturer.'

Kafka is also a member of a new National Committee for Clinical Laboratory Standards subcommittee charged with developing package-insert and labeling standards for home-use diagnostic products. The NCCLS subcommittee is chaired by Rosanne Savol, manager of regulatory affairs for the Ames Division of Miles Laboratories. "Labeling is of principal importance to everyone: industry, government, and the professions,' she says. "We want to identify the essential elements of good labeling and develop a consensus document by the end of the year.'

While the medical community is still trying to come to grips with the whole subject, self-tests already have the vote of the consumer. This despite the fact that most OTC tests cost two to three times as much as a comparable procedure performed in a clinical laboratory. In addition, when a patient phones his doctor to say that his gonorrhea self-test is positive, the physician will almost certainly schedule an exam and order a repeat assay through traditional channels.

What, then, are the advantages of self-tests? They're convenient: Patients can fit the tests to their own schedules, rather than having to fit themselves to the schedule of the doctor or lab. They're private: Many self-test users don't want friends--or even family--to know they have a health problem. They're informative: Above all, health care consumers want to know as much as possible about what's wrong with them so they can make informed decisions on whether and when to consult a physician.

In short, self-test give patients more control over their own health care. This increasing patient militancy is an issue that physicians and laboratories must address if they wish to keep health care consumers in the medical loop.

Physicians, for example, may need to find ways to incorporate self-tests into their evaluation of patients. Some are already taking this course successfully with home tests that monitor glucose or response of frequent urinary tract infections to antibiotic therapy. Diagnostic tests, however, present a thornier problem.

J. Stephen Kroger, who presented a paper on the analytical requirements for alternative-site testing at the CAP conference and is chairman of the American Society of Internal Medicine's Laboratories Committee, is generally in favor of home testing but sees some real problems with diagnostic kits:

"Say a person has urinary symptoms and thinks he has gonorrhea; he gets a gonorrea kit, and it's negative. What is he going to do with that result? He could have any number of sexually transmitted diseases. The problem with that approach is that it comes at the disease process from the wrong direction. When a physician makes a diagnosis, 70 per cent is based on history, 20 per cent on physical exam, and 10 per cent on testing. Home testing outside the medical system ignores 90 per cent of the diagnostic process.'

Enterprising hospital laboratories are already going after outpatient business to offset the economic effects of prospective payment ("The Rising Trend in Outpatient Testing,' MLO, May 1986). Offering a menu of tests to patients on a walk-in basis (assuming state laws prohibiting such practices can be repealed) seems like a natural extension of this practice.

Michael Kafka thinks that approach makes a lot of sense. "The home market is going to consumerize laboratory medicine. There will be continued home use of pregnancy tests, fertility tests, and glucose monitoring, but I think a lot of home testing is going to come back to the lab eventually. If we admit that home testing can be done, that people can decide on their own if they want a laboratory test, we should offer to do it for them and send the results to their physician if that's what they want. It will definitely be cheaper and more reliable.'

Laboratorians are also in a perfect position to serve as consultants to the self-testing industry. They can assist in designing controls, translating predictive values from the laboratory to the home setting, and providing interpretation of results.

As Paul Bachner puts it: "I think the only thing organized pathology can do is in some way get involved in evaluating the kits and systems in terms of their components. There's the whole issue of predictive value as a function of prevalence, which means it's going to be very difficult to translate results from the lab setting to the home setting.'

The modern era of self-diagnosis and care was fueled by the fitness trend of the 1970s and the backlash against the rising costs and increasingly impersonal nature of medicine. After the first home pregnancy test (Warner-Lambert's e.p.t.) hit the market in 1977, the idea rapidly took hold. More than a dozen OTC pregnancy kits are now available, with the newest and most sophisticated of these using monoclonal antibody technology to detect hCG as quickly as the first day after a woman misses her menstrual period.

Pregnancy test accounted for about $60 million in sales last year, according to Arthur D. Little, Inc., the consulting and research firm. They were second in volume only to glucose monitoring kits ($135 million). Sales of all products totaled $235 million.

Once the success of pregnancy kits made it clear there was a market for OTC laboratory tests, other manufacturers rushed to get their products on the shelves. The FDA approved more than 75 home kits in the last nine years, and self-testing expanded into the areas of colorectal cancer, fertility, urinary tract infection, and venereal disease.

Arthur D. Little expects sales to climb 21 per cent annually over the next four years, reaching $610 million in 1990. Self-testing would then account for more than 10 per cent of the total U.S. market for diagnostic products.

Categories of greatest growth, according to the firm, will be glucose monitoring and sexually transmitted diseases/urinary tract infection, among established areas. New tests on the horizon include strep screens, therapeutic drug monitoring (theophylline will probably be the first), electrolytes, calcium levels for consumers worried about osteoporosis, cholesterol, Pap smears, and cold and influenza screens.

Many of the manufacturers of self-tests, including Helena, Organon, Miles, Ortho, Ames, Monoclonal Antibodies, Quidel, Breit, Pacific Biotech, Streck, Boehringer Mannheim, Bio-Dynamics, and Lifescan, are already well known to laboratorians. Others, such as CB Fleet, Warner-Lambert, and Carter-Wallace, are more familiar as manufacturers of pharmaceuticals and consumer products. Still others are new names on the diagnostic frontier.

In the regulatory arena, self-tests come under the jurisdiction of the FDA's division of laboratory devices. They must fulfill the same manufacturing, quality control, labeling, and marketing requirements as in vitro reagents and instruments used in the clinical laboratory. Self-test kits may also incorporate labeling and package inserts keyed specifically to the lay consumer.

In general, manufacturers have designed their tests for very specific purposes, although some have more than one application. Screens for evidence of urinary tract infection, for example, can be used either to monitor the effectiveness of therapy or to diagnose the presence of illness.

Pregnancy tests are in a class by themselves because their purpose is to confirm an altered state of health. However, most home kits available today--and those expected in the next five years--fall into one of three general categories: monitoring, screening, or diagnostic tests. Let's look at each category.

Monitoring tests. Home glucose monitoring for diabetic patients started more than 60 years ago, largely as a result of Dr. Elliott P. Joslin's insistence that diabetics be responsible for as much of their own medical care as possible. The tests were cumbersome and time-consuming until the early 1940s, when Ames introduced the first urine reagent tablet for home use.

Since that time, the field has grown and gained acceptance by the medical community to the point where an estimated 10 per cent of the nation's 6 million diabetics do some form of home glucose monitoring. That figure is expected to rise to more than 30 per cent in the next five years, due both to changing therapeutic considerations and to new technology.

Intensive insulin therapy nmultiple daily doses) is fast becoming the treatment of choice for Type I diabetes, mandating multiple blood glucose tests each day. Blood glucose strips are now available from Ames, Bio-Dynamics, Lifescan, and Boehringer Mannheim, among others. Most can be read visually, but machine-read strips and reflectance meter monitors are making headway because they are reimbursable by Medicare.

Stephen Kroger points to home glucose monitoring as an example of how self-tests can be incorporated into quality medical care, "Diabetics are working with the physician. We have given them a rather sophisticated instrument (the reflectance meter), trained them in its use, sent them out, and had them test their blood on a regular basis--and not only test their blood, but make decisions based on the outcome of those tests. They will alter insulin doses if they are self-administering or on an insulin pump. They use that laboratory-derived information on a daily basis, and it has improved diabetic care tremendously.'

Besides blood and urine glucose, several other monitoring kits are available to help diabetics control their disease. Tests for urine protein give early warning of renal impairment, and determinations of either urine or blood ketone bodies signal impending ketoacidosis.

Diabetic self-monitoring is accepted by the medical community and endorsed by the American Diabetes Association because it demonstrably improves patient care, is accurate and relatively easy to use, and is done at the behest of the physician. Thus the procedure fits neatly into the existing health care loop, and it makes sense. It is impractical for diabetics to visit a laboratory once or several times a day to check glucose levels and adjust therapy. The tests are neither used nor marketed as diagnostic tools.

All of these factors favor physician acceptance of other home monitoring tests, such as urinary chloride titration for hypertension patients on low-sodium diets; determinations of urine pH, specific gravity, and uric acid to monitor fluid intake and diet for patients who are prone to develop kidney stones or--in the case of uric acid--gout; urinary bilirubin to signal recurrent hepatitis; blood urea to help dialysis patients decide when they need treatment; and cholesterol levels for patients at risk for coronary heart disease.

Other monitoring kits detect urinary tract infections via the presence of nitrite in the urine of patients whose infections are caused by nitrate-reducing bacteria. The nitrite test has been in use for years to gauge the effectiveness of urinary tract infection treatment, and some physicians are even willing to let longtime patients with a history of urinary tract infections perform the home test and phone in results to get a prescription.

However, the application for this self-test, along with a newer dip-and-read strip for urinary esterase, has now broadened to include home diagnosis of urinary tract infection. The medical community worries that patients will accept negative results at face value, even though they have symptoms, and fail to get proper diagnosis and treatment.

The newest and most technologically sophisticated tests currently available in the monitoring arena are fertility indicators. Based on monoclonal antibody technology, the ovulation predictors detect rising levels of luteinizing hormone in urine or saliva; the tests are used by women who want to achieve--or avoid-- pregnancy. The medical community has few complaints about these tests since they are not disease-oriented. Monoclonal Antibodies, Tambrands, and Ortho all have test kits on the market, and a number of other companies have products in development.

Also in development are tests to monitor serum levels of the therapeutic drugs. Therapeutic drug monitoring is one of the fastest growing areas in the clinical laboratory, and it's only a matter of time before products receive approval for the home market. With satisfactory quality control, home therapeutic drug monitoring has a potential for great benefit to patients on regimens of such drugs as theophylline, according to Stephen Kroger.

Screening tests. The best known type of home screening test currently available is designed to detect occult blood in stool as an indicator of colorectal cancer. CS-T (ColoScreen Self-Test) from Helena is the newest and simplest to perform example of this genre. It requires no fecal manipulation. The patient simply drops a reagent-treated pad in the toilet bowl after a bowel movement and looks for a color change that would indicate the-presence of blood in the stool.

Patients like the test because it spares them the ordeal of a rectal exam every year. Physicians are more cautious for a number of reasons, beginning with interpretation. Occult blood is not the only indicator of colon cancer, and a negative result doesn't necessarily rule out the disease. In addition, physicians are worried that patients will miss weakly positive results and fail to seek medical attention in time to treat a case of colorectal cancer.

They would much rather see patients follow American Cancer Society guidelines: For those over 40 years of age, an annual digital exam; for those over 50, add an annual stool guaiac test plus sigmoidoscopy once a year for two years, then once every third year. However, current patient compliance with the ACS requirements is so low that use of the self-test is virtually certain to improve detection rates.

According to Michael Kafka, there is a place for the home colon cancer screen. "Our hospital does it [encourages patients to perform colon cancer screens at home] and turns up 10 to 20 cases per year that way,' he reports.

On the other side of the interpretation picture, positive results do not by any means confirm the presence of colon cancer. In fact, the likelihood is that the patient has polyps, hemorrhoids, diverticulitis, colitis, or a duodenal ulcer instead. Physicians fear the patient may not realize this and may panic at a positive result. Fortunately, package inserts clearly direct the patient to consult a physician in the event of a positive result.

Screening tests now in the works include a Pap test for cervical cancer and a heat-activated evidence designed to detect breast cancer.

Diagnostic tests. Home diagnostic tests are a whole different ball game from monitoring and screening assays. For the most part, they are instigated entirely by the patient without any physician guidance. For another, no one seems to have any clear idea about how to fit them into the traditional health care system.

Although Stephen Kroger supports the idea of home monitoring and screening tests, he says flatly, "I personally would be very uncomfortable using home diagnostic tests in my own practice. The liability for a diagnosis falls on me, not on someone who brings a test in to me. If I use that test as a basis for my diagnosis and it later turns out that the test was wrong and I treated the patient incorrectly, there's no question who's liable. I am.'

Available diagnostic tests include assays for urinary tract infections, candidiasis, strep throat, and gonorrhea. Self-testing for sexually transmitted diseases is particularly controversial because, as Michael Kafka explains, "You can't guarantee compliance, treatment, and follow-up that's


Medical Frontiers, manufacturer of the only venereal disease self-test on the market (V.D. Alert gonorrhea test for men), maintains that its kit is designed to bring people in for treatment. Although the company analyzes test results itself (users mail a slide specimen, then call in to get the results), it disclaims any responsibility for reporting positive tests to health authorities. Users are guaranteed anonymity; when calling in, they reveal only a code number printed on the kit. The medical community is worried that asymptomatic men who test positive will ignore the test results, failing to get treatment or to notify their sexual partners.

Gonorrhea kits and all other diagnostic self-tests have another significant drawback, according to Paul Bachner. "What we're most concerned with is the significant false negative: the person who tests for something--gonorrhea or cervical cancer--comes up with a negative result and thinks he or she doesn't have to worry because it's negative, when in reality it's a technical false negative or a sampling false negative.'

This is a particularly troubling issue because home tests are not subject to the same proficiency testing regulations that govern clinical laboratories. Manufacturers resist the idea because it would increase costs.

Are there any circumstances under which physicians might accept the results of self-tests for diagnosis? Stephen Kroger mentions one: "If a patient of mine had recurrent urinary tract infections, I wouldn't have any problem with telling him to use a kit. If it was an individual I didn't know, I would be very reluctant to prescribe or treat over the telephone. If a patient expects to present a doctor with laboratory tests and a set of symptoms over the phone, basically telling him what the diagnosis is and asking for his signature on a prescription blank, and the doctor does it, he's not practicing quality medicine.'

These objections notwithstanding, Kroger sees a future for self-tests if they are promoted as a cooperative venture with the physician rather than as an alternative to traditional medical care. "As these tests proliferate, physicians will have encounters a whole lot more often than they do now. The only way the individual is going to make any progress with his physician is by staying within the system. Somewhere along the line, that kind of cooperation needs to be spelled out very explicitly.'

Michael Kafka thinks that, for the moment, self-testing is beyond control of the medical community. "For a while, there will be only two things that are going to determine whether a test will be available on the market. First, whether it can be practically packaged: Is the technology mature enough and durable enough that it can be put out on a shelf and sold like a loaf of bread and taken home by someone who has absolutely no technical expertise to do the test? Second, whether there's a perceived market. I don't think it makes any difference whether it's medically useful.'

However, Kafka feels the whole field will eventually settle down. "It's going to take a few years to work through, but it's very hard to totally strip a test out of the medical environment, put it in someone's hands, and say: "Go ahead and test, and then you decide what to do with it.' There will certainly be continued use of home pregnancy tests, ovulation detectors, glucose monitoring, and screening kits, but the rest will come back to the lab eventually.

"What we have to pay attention to is that people want more control over their medical care, more responsiveness.'
COPYRIGHT 1986 Nelson Publishing
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1986 Gale, Cengage Learning. All rights reserved.

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Title Annotation:home kits for glucose monitoring and pregnancy testing are big sellers
Author:Brennan, Leslie
Publication:Medical Laboratory Observer
Date:Aug 1, 1986
Previous Article:Laboratories fare well under revised hospital regulations.
Next Article:Test your knowledge of AIDS: a self-quiz.

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