Nowadays, ‘personalized medicine’—often used interchangeably with ‘precision medicine’—is
a trendy topic in popular and medical media. The term suggests a significant new development
in clinical medicine; authors often claim a paradigm shift in healthcare. University
hospitals proudly announce the founding or planning of initiatives dedicated to research
in ‘precision medicine’ and politicians are eager to provide the funds for these important
medical developments [1].
With our emphasis on tailored care for the individual patient, evidence being one
ingredient for decision-making but personal preferences and circumstances of the patient
playing a major role as well, one might wonder whether general practitioners (GPs)
have not always been practicing ‘personalized’ medicine.
What is ‘personalized medicine’?
Let us first have a look at some definitions. The Centre for Disease Control explains:
‘Precision medicine, sometimes called personalized medicine, is an approach for protecting
health and treating disease that takes into account a person’s genes, behaviours,
and environment. Interventions are tailored to individuals or groups, rather than
using a one-size-fits-all approach in which everyone receives the same care’ [2].
The National Research Council explains: ‘Precision Medicine refers to the tailoring
of medical treatment to the individual characteristics of each patient. It means the
ability to classify individuals into subpopulations that differ in their susceptibility
to a particular disease, in the biology or prognosis of those diseases they may develop,
or in their response to a specific treatment. Preventive or therapeutic interventions
can then be concentrated on those who will benefit, sparing expense and side effects
for those who will not’ [3]. The medical specialty most often referred to in relation
to ‘precision medicine’ is oncology. General applications are the identification of
individual risk factors for developing a disease (disease susceptibility), prediction
of the response to pharmacological treatment (pharmacogenetics) or determination of
the likelihood for serious adverse events after a drug is given.
These definitions and explanations should immediately remind us about a similar term,
describing one of the core competencies of our discipline: the ‘person-centred approach.’
As the Wonca definition reads: ‘The general practitioner/family doctor develops a
person-centred approach, orientated to the individual, his/her family, and their community.
Family medicine deals with people and their problems in the context of their life
circumstances, not with impersonal pathology or “cases”. It is as important to understand
how the patients cope with and view their illness as dealing with the disease process
itself. The common denominator is the person with his or her beliefs, fears, expectations
and needs’ [4].
From comparing these various definitions, it becomes clear that the terms ‘personalized
medicine/precision medicine’ and ‘person-centred medicine’ are in fact all referring
to the most important focus of high-quality care: the person in front of the doctor
asking for advice or help. To provide optimal medical care, the experienced GP always
had to take into account the detailed history of individual patients and their families
(‘genetics’), their individual background in terms of social and occupational circumstances
(‘environment’) and their individual approach to health and disease such as adherence
to therapy, coping mechanism and lifestyle (‘behaviour’). Each experienced GP also
knows the challenge of treating patients with the same condition but with a different
response to identical treatments, e.g., for pain, hypercholesterolaemia, hypertension
or diabetes. As a result, in general practice, treatment of individual patients routinely
is ‘personalized’ or ‘individualized.’
Personalized medicine is nothing new
Obviously, the traditional approach of GPs to individual peoplès health problems is
quite similar to the meaning of ‘personalized or precision medicine’ and is, therefore,
nothing new. Just remember the famous quotes by William Osler from the nineteenth
century: ‘It is more important to know what sort of person has a disease than to know
what sort of disease a person has.’ His advice to students was ‘Care more particularly
for the individual patient than for the special features of the disease’ [5]. Only
the methods accessible to practice personalised medicine are nowadays different and
new: examples are the tests for BRCA1 or BRCA2 mutation to determine the risk of breast
and ovarian cancer or the test for CYP2C9 polymorphism to predict the optimal dosage
of coumarin derivatives before treatment is initiated. While high-tech specialist
medicine increasingly relies on genetic tests or ‘-omics’ technologies, GPs pursue
the same goals by low cost methodology: continuously learning about the family history
of their patients, which is relevant to build a sound knowledge over time about individual
genetic risks, behaviour, response to treatment or adherence [6].
What is new?
Despite the similarities between the ‘person-centred approach’ in general practice
and ‘personalized or precision medicine’ in some specialities, there is, in fact,
a major paradigm shift in medicine and in healthcare in general. For the management
of patients in terms of diagnostic and therapeutic procedures, GPs and specialists
alike have become accustomed in the past to consider disease-specific guidelines with
the aim of standardizing the care for all patients with a given condition. Healthcare
administrators and policy-makers saw standardization in healthcare as a way to improve
patient care and at the same time keep healthcare affordable. On the other hand, practitioners
are critical about the concept of using practice guidelines as ‘cookbook medicine’
or as the only ‘correct recipe’ for patient care. As Wonca World’s former president
Richard Roberts once said: ‘Guidelines are for standard patients … but I have never
met a standard patient!’ (Wonca Europe Conference, Basel, 2009). Therefore, the scientific
developments in genetics and in genetic testing to identify subtypes of various diseases
or subtypes of responses to drug treatment have now paved the way to the broader recognition
of tailoring medical treatment to the specific characteristics of individual patients
with a disease. This shift away from thoughtlessly using a ‘one-size-fits-all’ approach
to medical care can be considered as progress and relief. Moreover, is such an approach
not evidence-based medicine at a state-of-the-art level?
Could new developments in personalized medicine be helpful in primary care?
Since the achievements of the Human Genome Project, genetic tests are increasingly
available and their high costs will eventually get lower over time. At the higher
levels of healthcare and at the direct consumer level their use for individual patients
likely will increase. For primary care, it will undoubtedly take more time until relevant
genetic tests for point-of-care use will be accessible. If affordable for public healthcare
systems, such a development would certainly help to inform decisions of the family
doctor. However, collecting comprehensive information about the individual family
history of patients (‘primary care genetics’) and using this knowledge for their management
will certainly remain to be a pillar of high-quality general practice at low cost
for the healthcare system [7].
In conclusion, the concepts of ‘personalized medicine’ and ‘precision medicine’ as
well as ‘person-centred medicine’ refer to the ability to use hereditary information
to ‘personalize’ treatment. This approach has existed in medicine since time immemorial,
in particular in the field of general practice. However, recent technical advances
in genetic testing allow assessing this information of individual patients more accurately.
Manfred Maier
Department of General Practice, Centre for Public Health, Medical University of Vienna,
Vienna, Austria
manfred.maier@meduniwien.ac.at