Asks Rod:
I heard a mention on the radio the other day about the FDA approving a home HIV test kit. What’s your take on this development?
[snip]
Do you think it will be effective at reducing the infection rate? How is this going to affect gay dating behavior? What are the rates for false negatives and positives? How might that inadvertently affect rates of other STD infections? That sort of thing.
I am mostly happy about the development. I think people should have as much information about their own health as possible, generally speaking. And knowing one’s HIV status is incredibly important in preventing spread to others. So on balance I’m supportive of home testing kits.
I don’t know a tremendous amount about the home tests, but my understanding is that they are essentially the same as oral swab tests that have been provided by clinics and testing centers for years. As for false positives and negatives, there’s this:
The test is pretty reliable at detecting the disease, returning a false positive in just 1 in 5,000 tests (a 99.98 percent accuracy). Its false negative rate of 1 in 12, however, means a lot of people infected with HIV will still remain undiagnosed if they don’t followup on the OraQuick test with further testing. Still, the test’s effectiveness in detecting people with HIV will bring a lot of people to the clinic who would have likely sought medical help only after the disease had advanced.
The false negative rate gives me pause. One of the potential harms from a home test is that it would yield a false negative, either because it was performed incorrectly or the patient was in the window between being infected and producing detectable antibodies (which is what test kits like these would be finding). A false negative could lead to people engaging in riskier behaviors because they erroneously believe they can’t transit infection.
My other worry is related to this, and concerns the lack of pre- and post-test counseling. While studies have been equivocal in determining how effective counseling is at reducing risk behaviors for HIV-negative patients (citation buried midway here), at least patients who get appropriate test-related counseling from a provider or health educator are advised of the potential for a false negative, and should be advised to get retested in a few months if there is risk of recent infection.
But my biggest worry is about the lack of post-test counseling for people who would get positive results. From the same CDC link above:
HIV-positive test results should be communicated confidentially through personal contact by a clinician, nurse, mid-level practitioner, counselor, or other skilled staff. Because of the risk of stigma and discrimination, family or friends should not be used as interpreters to disclose HIV-positive test results to patients with limited English proficiency. Active efforts are essential to ensure that HIV-infected patients receive their positive test results and linkage to clinical care, counseling, support, and prevention services.
I have told patients they were HIV-positive three times, once in medical school and twice during my fellowship in adolescent medicine. The first patient took the news with surprising calm, particularly considering that it was just before the advent of HAART regimens, when the diagnosis was still pretty dire. (I don’t know what happened to him [I graduated not long after], but hope he’s doing well since the regimens went into widespread use not long after he got his results.) The other two were understandably distraught. (Even though I tried to deliver the news with as much compassion as I could, I still sometimes wonder if I could have done better.) At the time I was working in a large, multidisciplinary clinic, and the patients went directly from their appointments with me to meeting the (awesome) social workers who would be helping them deal with the diagnosis and co-managing their care in the future, along with the physician who coordinated the HIV program using an std risk calculator. They were immediately connected with all kinds of supportive people. While obviously no amount of counseling or education can negate the pain of such a massive diagnosis, it can certainly mitigate some of the isolation and despair that might otherwise descend on a person getting such bad news.
A patient getting a positive result sitting at a kitchen table is on his or her own. I worry about what would happen to those people. Certainly some (hopefully most) would find loved ones to tell and medical providers to care for them. But I think it’s reasonable to fear that some would choose home testing not because of convenience, but because they fear the stigma of going to a clinic or testing center. I think it’s reasonable to fear that a positive result revealed at home will only deepen these people’s isolation at the precise time when they need help and support the most.
Everyone should know their HIV status. Insofar as home testing kits will give people information about their own health, and help them make better decisions about the risk behaviors, I think they are a good thing. But professional services surrounding the diagnosis of HIV exist for a reason, and I worry about the harms that may come from trying to do without them.
I understand your reservations. I wonder if the home-testing kits also have something to do with avoiding being marked by the disease for insurance purposes. I’m aware that there already are anonymous ways to get tested, but I imagine home testing gets some of its support from that concern.
Of course, if the ACA is not repealed, and if it works as it’s supposed to, then perhaps this will be less of a concern than previously.
Sometimes it’s not that neat.
When I was in college an ex-girlfriend called me to say she had tested positive for antibodies during a screening for blood donation. No counseling, no doctors, just a phone call from my ex saying “heads up”. She was fairly sure that it was a false positive due to her extensive vaccinations before traveling abroad for missionary work, but for the few weeks where we did not know for sure, it was pretty traumatic.
Could I keep teaching with a compromised immune system? How much do I disclose to the school? To parents? To students?
A lot of questions….
While the relatively high False Negative rate is scary, I think I’d rather just plan to take a couple of tests over a month to be sure, rather than go through another False Positive.
And since I have been screened myself and am HIV-
One of the benefits lost from taking this test out of the laboratory is the public health benefit from this being a mandatory reported disease. With a home test there is no guarantee that the diagnosed will seek medical aid or notify their past and previous partners.
Excellent point, and one that had completely eluded me.
Russ-
Do you fully support sich mandatory reporting?
I think to say I “fully” support mandatory reporting would imply more enthusiasm than I feel. I definitely support them, because they are vital for epidemiological purposes writ large and for making sure potentially infected people are appropriately identified on an individual scale. That said, I recognize and understand that this involves a necessary trade-off in compromised privacy, no matter what safeguards may be put in place.
How exactly does such reporting work? That might help clarify the issue, at least for me.
I see it much less of a slam dunk that it appears others do, which might be my ignorance shining through.
I can tell you how it’s meant to work, at least as far as I understand it.
Patients who test HIV+ are asked to give contact information about recent sexual contacts. Their positive status is reported to state agencies, though to what degree their identifying information is blinded is unclear to me. Known sexual contacts are contacted and told that they “may have been exposed to HIV” and encouraged to get tested themselves, though no names or other information are used.
However, if Sexual Contact X knows that he or she has only had sexual contact with Person Y in the last six months, such a disclosure will give X a pretty good idea that Y is HIV+. Given the stakes involved, I believe this compromise in confidentiality is warranted.
Thanks.
Is this system unique to HIV/AIDS? Are there other diseases that are afforded such a system? If not, are there anything that you think ought to be?
If an awareness of mandatory reporting led a non-zero amount of folks to avoid testing or seek home testing, would that change your feelings at all?
I believe there are gestures toward finding and contacting sexual contacts of patients with other reportable STIs (eg. chlamydia, gonorrhea), but my impression is that this is really not undertaken with much gusto. HIV is (in theory, at least) treated more seriously.
Pre-test counseling is meant to inform people who desire testing that there will be efforts to inform their sexual contacts should their results be positive. Does this lead to a non-zero number of people eschewing testing? Probably. That being the case, I still support current practice.
That was the first thought that occurred to me, actually. The mandatory notifications. It’s not enough that I think these tests should be banned, but it’s definite cause for concern.
The other thing being the legal liability involved. If they can prove you know, and you went out and slept with other people without notifying them, you could be in for some serious trouble. But if you took the home test, then the likelihood of being able to prove that you know drops considerably. Or maybe with HIPAA it doesn’t make a difference?
I was unaware of mandatory reporting.
There are many diseases, that for reasons of public health, have mandatory reporting requirements. This link, http://www.michigan.gov/documents/Reportable_Disease_Chart_2005_122678_7.pdf , is for the state of Michigan.
Thanks, Russell!
It occurs to me that a lot of the possibly negative dynamics would be alleviated were the alpha and beta errors reversed.
By which I mean… if you tested positive but there was a significant chance it was a false positive, that would probably spur a lot of folks to go get a re-test at a clinic. Then all the counseling and such could kick in. BTW… are clinic tests more accurate?
Depends on the test. If it’s a cheek swab, probably not much, except insofar as a clinic worker may obtain a sample using more correct technique.
A blood test, especially a western blot, is much, much more accurate.
The medical system I work for screens with a blood test — ELISA based — and if positive confirms by Western blot.