Full reference: Sugrue L.P. and Rahul S. Desikan, R.S JAMA May 14, 2019 Volume 321, Number 18 1820 -1821
This weeks blog is brought to you by: Professor Sir Muir Gray
Authors conclusion – Text from the paper chosen by 3VH
Value
“The value of polygenic risk scores cannot be assessed until the clinical utility has been established through research studies that evaluate their use in clinical practice and therapeutic trials. Companies are already offering these tests directly to consumers at costs ranging from one to a few hundred dollars. As whole-exomesequencing and whole genomesequencing become less expensive and more widely available, it should be possible to compute any polygenic score from an individual’s genomic data at a low cost.
Evidence Base Polygenic risk scores for common complex disease have yet to become part of routine clinical care or be included in the practice guidelines of any major medical organisation. Before polygenic scores can be translated into clinical practice they will need to be extensively validated in clinical and population-based cohorts for their ability to predict meaningful outcomes that can be modified with intervention”.
Bottom Line
Polygenic risk scores for common complex disease will become part of clinical care in the near future. That said, genetic susceptibility for complex conditions should not be viewed in isolation but be considered along with lifestyle and and environmental factors in multivariate evaluation of disease risk.
3VH – Implications for value
One of the reasons why need and demand are increasing faster than resources is the continuing development of new technology. Even if the technology has evidence of high value it can still cause problems if it is allowed to drift into practice without stopping, and switching the resources from, the technology which has been made redundant. When there is no evidence of effectiveness the problem is obviously much greater. This paper is balanced and sensible as the quotation from the paper illustrates.
However the genie is out of the bottle and one can just imagine enthusiastic clinicians adding such tests to their practice, and even more alarming the tests of no proven value are being promoted privately. Even though the test might be paid by the citizen, because they are not patients, the positive test results will be taken to the health service generating work and expense.
If there is a culture of stewardship and a budget for the system for a specific sub group of the population, for people with heart disease for example, then the clinician responsible for the whole population of people in need would be able to control the introduction of polyvalent tests in their network but what is she to do with the privately generated referral? The answer is clear, the person should be told that the NHS cannot offer them any service because it would mean depriving other people of high value care and that is contrary to the principles of value based care.
This technology is creeping in and we need to develop a strategy and language for an epidemic of false positive, zero value referrals.