We now have the entire human genome defined and “sequenced”
and the costs of this clinical sequencing for individuals have decreased
dramatically. In medicine today, that
knowledge is being used to develop new tests so that health professionals can
use the genetic tests to assist in making a diagnosis and deciding on treatment. However as the costs of whole exome and
genome testing go down even more, a price point is nearing at which it will be
less expensive to do a complete clinical sequencing than to do specific genetic
tests. This promise of more genetic
information at lower costs creates the possibility that we will have more
information that can potentially help the patient. There is also the promise of finding abnormalities
that we did not anticipate. This is what
the American College of Medical Genetics calls “incidental findings” and is no different
than that seen in many areas of medicine today.
When a doctor sends a person for a chest x-ray, or a chest CT for a
cough, unanticipated and incidental findings may be seen in the bones that are
visible on the imaging study as an example.
With complete clinical sequencing however the number of secondary and
incidental findings may be significantly larger than we see today with other
diagnostics.
In recognition of these emerging facts, the
Institute of Medicine hosted a 2 day meeting in July 2012 to help understand
the economics of adopting whole genome sequence information into health
care. That led to a report of the meeting and also
to a “viewpoint” published in the Journal of the American Medical Association entitled "The Economics of Genomic Medicine" that described the main agreed upon insights by the participants. In my words, their points were:
- Genomic researchers, health care practitioners, payors, and economists are all speaking different languages and have no comfort with the languages of the other disciplines making any discussion of value and economics difficult.
- There is little to no evidence at this time demonstrating that genomic data favorably affect health outcomes.
- We don’t know how to use and explain this clinically sequenced data to people in any sort of logical, understandable and cost effective manner to produce value. We just don’t know what to do with these genetic facts so health professionals have a hard time educating and counseling their patients on the implications of the clinical sequencing.
- We don’t understand “personal utility” and its role in assessing the value of sequencing. Personal utility describes the meaning and worth any test or intervention brings to an individual from that individual’s perspective rather than from any external metric such as morbidity or mortality or from an expert’s perspective.
To summarize, we don’t know
the value that this clinical sequence has for an individual, we don’t know how
to talk about it, we don’t know how to measure its value, and the experts don’t
completely understand one another.
Admittedly that makes discussing the economics difficult at best. It also creates a dilemma for the payors, both
private and government, about what should be paid.
In this country, we have a
combined pre-paid health care model and a health insurance model to pay for care. Insurance is a way of sharing the financial
risk of relatively unusual high cost events while pre-paid health addresses the
costs of preventive care and screening which are not at all unusual. Preventive care and screening are encouraged
and paid as the value from both a public health and a moral point of view are
believed to be worth the cost. The
theory is that finding clinical risks early leads to lower costs of
treating disease and thus would also be advantageous for financial risk. The economic reality has proved to be more
complex however and is dependent on the specific clinical issues and the
specific use of the information that screening uncovers. That has led to tremendous debates in the
public arena concerning specific tests, such as debates around the use of PSA
testing for the risk of prostate cancer and the appropriate age to start
screening with mammography for breast cancer.
These debates occur as we attempt to find definite answers to questions
that can really only provide us with statistical estimates of both clinical and
financial risk.
Risk is nothing more than a
probability based on data. This is true
for both clinical risk and financial risk.
We now routinely treat disease risk, as much or even more than we treat
disease. We screen for silent illnesses such
as hypertension that may not be symptomatic to prevent them from causing
problems in the future and try to find illnesses at earlier points in their
course to affect cures such as screening for breast cancer and colon cancer. But we don't really know what would have happened in each case had we not screened. We can only estimate the probabilities of both clinical outcomes and financial outcomes.
With clinical sequencing, we
have entered the potential for a new world of health risk. Right now, the issue is one of deciding how
to report the incidental findings from a clinical sequence. The American College of Medical Genetics has
spent the last year developing a policy statement on just this issue with the
draft recommendations now being circulated among members of the college. Part
of their effort is an attempt to identify clinically relevant incidental test
results and then recommending whether or not such findings should even be
reported to the patient. But this is
just the beginning. As our understanding
improves we will quantify new risk probabilities and thus new test "results" based on the clinical sequencing
and the number of incidental findings may multiply.
I wonder if some of their
efforts to control what is reported are in vain and are an outgrowth of the
different language they, as experts in genetic diseases, speak when compared to
the patients and the public who see the open dissemination of all available information
as a human rights issue and a patient autonomy issue, rather than a test
reporting issue. The ability of any
health professional or any expert organization such as the ACMG to define what
results a patient should see and should not see is likely to be strongly
challenged and will probably ultimately be refuted.
This can lead us to a situation
in which the multiplied “incidental findings” which are reported can lead to patient
demands to find reasons for these findings and to attempt to modify any risks
inherent in these results. That can only
lead to higher total costs with little potential benefit at this point of
knowledge.
In this scenario, the
economics become challenging. Who should
pay for this type of attempt at risk mitigation when the likelihood of clinical
impact will likely be low for some time to come? Will it be decided by the American College of
Medical Genetics which will look at clinical utility or by the yardstick of “personal
utility”? I am as unsure as the members
of the esteemed IOM panel. While the
potential for good is exciting, the potential for increased financial and
clinical risk from attempting to predict and cure every possible illness is a
bit overwhelming. We will need to be
very careful as we try to address the excellent points made by the Institute of
Medicine Committee.
Dr. Spiro - I agree with you that there too many unknowns in genomic sequencing and that the interpretation is a challenge both for geneticists and clinicians. However, I believe that with time and real life practice everybody will become more proficient. The situation is becoming reminiscent of early days of the MRI - technology is there, and in theory should be great tool, but not every doctor can "read" MRI data. Specialists become more adept and programming and electronically-assisted interpretation enable wide use of MRI, and hopefully one day genomic sequencing as well. Still debate is going on whether all MRI scans are medically justified, some rightly argue that MRI is overused, but it does not prevent patients from accessing this diagnostic option.
ReplyDeleteSecondly, as of medical utility - just last week I, as a genetic constant of geneyouin, I was trying to help a client to find which antihypertensive treatments might be better suited for him through pharmacogenetic testing but very brief investigation brought me to suspect that the client has a Liddle syndrome (uncontrollable hypertension diagnosed at age of 16, with strong familial history of disease). We are now resorting to genetic testing to confirm the hypothesis, which was not even raised by his family physician. The case demonstrates that genetic testing is just another tool that physicians should use, particularly when they are not sure of diagnosis. Genetic testing is not a solution for all problems but in isolated cases might make a huge difference for the patient.