Moving from Population Medicine to Personalized Medicine

Health Technology Assisting the Move from Population Medicine to Personalized Medicine

In the United States, despite high hopes, our health-care system still generally operates as a one-size-fits-all model. Some refer to this as a population model. This paradigm suggests that in the majority of people, an ailment—be it a common cold or cancer—has a common predicted trajectory, and most people will benefit from a homogeneous course of treatment. If a particular treatment does not work, then the second-most likely successful treatment plan is prescribed.

This continues until the ailment is relieved. Treatments are set based on available population statistics, and trial and error is used until the patient is well. In this model of medicine, personal characteristics, risk factors, lifestyle choices and genetics are rarely considered. Therefore, the treatment approach will not be ideal in all cases, failing those who do not fit with “average” parameters.

Personalized medicine, on the other hand, advocates the customization of health care. It aims to prevent diseases, as well as tailor treatments to an individual so a disease or illness can be targeted in a way that promises the highest chance of success based on the attributes of the individual. An underlying assumption of this approach is personalized medicine (PM) takes into account that drugs and interventions will have varying efficacy based on the person being treated.

Health Technology in the Age of Genomics

Now that science possesses a complete map of all the genes in the body, personalized medicine is manifesting as a reality.

The National Human Genome Research Institute emphasizes that personalized medicine involves the use of a patient’s genetic profile to guide decisions regarding prevention, diagnosis and treatment. Modern health technology now allows for the individual’s genome to be examined in order to detect specific characteristics or abnormalities.

Angelina Jolie’s public disclosure about carrying a BRCA1 gene mutation, which puts her at high risk of breast cancer and ovarian cancer, brought some of these concepts to the public’s attention. Making choices based on gene type might not yet be the norm in everyday health-care practice, but it is becoming more prevalent.

Oncology is an area of medicine where DNA sequencing technology has a lot of potential. For example, for lung cancer, there are many personalized treatment options now available based on different lung cancer biomarkers. If there is a medical indication, genetic tests can often be covered by insurance, especially if there is an FDA-approved drug or treatment that is tied to a genetic mutation.

Recently, researchers have also used DNA sequencing to establish the connection between bovine leukemia virus (BLV) and breast cancer. It was previously believed that this cattle virus cannot infect humans. However, a study conducted by the University of California, Berkeley, and the University of New South Wales, Sydney, showed that BLV can be present in human tissue three to 10 years before cancer gets diagnosed, indicating a strong correlation.

Genome-driven medical care is becoming increasingly utilized due to the development of next-generation sequencing (NGS) technologies.

According to The National Human Genome Research Institute, whole genome sequencing can now be performed in less than 24 hours for under $1,000. The genetic services have become more accurate and affordable and are now used in both public and private institutions. However, numerous challenges still need to be tackled. For instance, many doctors may lack training opportunities and are unfamiliar with the emerging technologies. Some experts also warn that there needs to be a balance between hope and hype and that ethical issues should be strictly monitored.

A New Organ from Your Own Cells

Perhaps one of the most sensational innovations in the area of personalized medicine is printing 3-D organs from one’s own cells. It is predicted that in about 10 to 15 years, organs will routinely be produced from cells harvested from patients themselves using 3-D bioprinting technology. In the future, organ transplantations might eventually be replaced by customized organ-growing.

Anthony Atala, M.D., the Director of the Wake Forest Institute for Regenerative Medicine (WFIRM), has already demonstrated that transplantable kidneys can be produced using such a technique, helping to curb a crisis resulting from organ shortage. Currently, scientists at WFIRM are engineering over 30 different tissues and organs that could be used as replacement organs. Organovo, a company working on personalized bioprinted human tissue, has so far produced 3-D liver models that stay functional and stable for up to 60 days, which is an improvement from the previously established functionality of 28 days. The printed liver tissue can be used for drug testing, offering an alternative to animal and in vitro experiments. It also offers new hope to people with various genetic conditions who could benefit from a transplant. In 2016, Chinese scientists successfully printed a part of the heart’s left atrium (left atrial appendage). Occlusion of this part can play a role in preventing stroke in patients with atrial fibrillation.

It appears that 3-D technology can offer an improved presentation of an individual’s left atrial appendage compared to conventional imaging methods. This is essential for surgeons as they need an accurate preoperative reference before they start with the occlusion procedure.

Mobile Technology and Personalized Medicine

Eric Topol, the Director and Professor of Genomics at Scripps Translational Science Institute, describes the now-ubiquitous smartphones as the hub of future medicine. Mobile phones and mobile peripherals can be used as biosensors—measuring blood pressure, heart rhythm, blood sugar levels and even brain waves—as well as functioning as a personal scanner such as an otoscope or ultrasound. People can now perform many measurements by themselves, when they want and where it is most convenient for them. They can view and interpret their data without having to visit the doctor, making health care increasingly more personal and individual-based.

Ethical Issues Surrounding the Development of Personalized Medicine

Since the dawn of personalized medicine, several limitations of this approach have been discussed. Some experts argue that it carries a risk of reducing medicine to molecular profiling. A properly executed traditional medicine practice should already include a degree of personalization by looking at your unique characteristics, medical history and social circumstances. Many social scientists and bioethicists believe that the label “personalized medicine” could involve a radical shift of responsibility toward the individual, potentially dismissing other socioeconomic factors that are important to examine as well. The approach might in some cases contribute to the culture of “blaming the victim,” creating stigmatization of certain groups of people and taking the public health resources away from initiatives that try to address the social disparities and inequity that also affect health.

An article published by the Hastings Center—a research institute that addresses ethical and social issues in health care, science, and technology—highlighted that there might be some erroneous expectations surrounding personalized medicine. It is very unlikely that in the future, you will be able to receive a unique prescription or a treatment specific to you alone. Personalized medicine is more about classifying people into groups based on genomic information and looking at your health risks and treatment responses in the context of that genetic group.

Many people are concerned that being classified as a member of a certain subgroup could, for example, increase your insurance rates or make you a less desirable job candidate. These considerations are not unfounded. Personalized medicine goes hand in hand with increased data accumulation, and data security remains a challenge. Moreover, being in a certain subgroup might oblige you to participate in screening programs as a matter of social responsibility somewhat reducing the freedom of personal choice.

There are also potential ethical implications for doctors handling genomic information. For instance, doctors might need to contemplate withdrawing some pieces of information that have no medical utility. The disclosure process would require some careful editing to prevent confusing or scaring the patient further. However, this could signal the return to paternalistic medicine where the doctor decides what is best for you and what you should be told. There is clearly a need for a solid ethical framework in this field, as well as a need for careful monitoring to ensure concerns are balanced with benefits.