Why we do what we do — Earlier Rare Disease diagnosis
At Mendelian, we build tools to help doctors find rare disease patients faster and diagnose them earlier.
There are two key facts most people miss about rare diseases:
- Rare diseases are not rare. We call them “rare” because each disease, individually, affects only a small number of people. However, as there are more than 8,000 rare diseases, collectively they are common. With 1 in 17 people affected or ~350 million people worldwide, they have a global prevalence similar to Asthma. Besides, the latest estimates show these numbers are growing (which is largely due to a broader clinical trend of disease segmentation). Furthermore, it is likely that these numbers still underestimate the scale of the problem. A large portion of the rare disease patients remain undiagnosed their whole life; which brings us to our second key fact.
- Rare diseases are very difficult to diagnose. Essentially, this is a systemic information challenge. Early in our medical education system, the key pillar of clinical training is: “When you hear hoofbeats, think of horses, not zebras”. Rare diseases are the zebras. The extent of the problem is disturbing. In the UK it takes, on average 5 years to diagnose a rare disease patient. From first presentation of signs and symptoms to correct diagnosis. This is too long.
Clinicians — Why is it so difficult for doctors to diagnose patients?
Rare diseases are hard to spot early. Many are progressive and multi-systemic. The symptoms appear gradually, spread over both different systems of the body and the months and years. Consequently, specialists dealing with one system, for example the heart, won’t see or recognise the whole picture. There is no rare disease specialist. Patients are passed around different doctors with the whole story never being fully put together. It’s challenging for doctors: not only they may have never seen a patient with that condition before, rare diseases definitions are also constantly being reshaped, and new ones are being discovered every day. It’s intractable and impossible for clinicians to keep up to date.
This delay in diagnosis has dire consequences for the patient and at scale, the entire healthcare system:
For the Patient — No Diagnosis, No Hope
During this 5 year journey looking for a diagnosis which patients call their “diagnostic odyssey”, patients are being dragged from pillar to post of the medical workflow. Meeting countless clinicians and health professionals, receiving several misdiagnoses, undergoing a battery of inconclusive tests, and ineffective, potentially harmful, treatments. This “diagnostic odyssey” has a significant psychological impact on the individual and their loved ones. Frustrated at the process, the lack of answers, they are sometimes not believed by clinicians as their problems fall outside the normal experience of that health care professional.
Many rare disease patients recall the day they finally got a diagnosis as the most important day of their life.
Another serious outcome of delayed or missed diagnosis, is the lack of options. Without a diagnosis, there are no experts, no centres of excellence, no patient advocacy groups. There are no explanation for the problems patients suffer, which is a significant issue when trying to access the help and support they need for day to day living, care, education and work. Evidently, without a diagnosis there is (no treatment and) no hope for treatments. No diagnosis also means no clear prognosis i.e no way to predict the disease progression. Will the patient get better? How will the symptoms evolve? How long may they live? Will this disease affect others in the family and any future children?
Diagnosis is the starting point for answers.
For the Healthcare System — Undiagnosed patients are a challenge
Undiagnosed or misdiagnosed patients are a significant burden on the healthcare system. The mismanagement of a disease often results in symptoms that are difficult to control for which the patient seeks repeated medical attention and multiple inappropriate therapies. Patients deteriorate, complications accumulate, these are often irreversible and as such, the opportunity to alter the course of a disease by early intervention may have been missed. Patients are left with disabilities they may have otherwise been able to avoid. Furthermore, whilst searching for their diagnosis, they undergo extensive and costly investigations. An accurate, early diagnosis has the potential to not only significantly improve the quality of life for patients but also reduce the cost and pressure on our healthcare system across primary, secondary and tertiary care.
In a world where precision medicine is the new holy grail, where genomics is becoming democratised and where rare diseases get the awareness they deserve, we should rethink the diagnosis process of our most challenging patients.
At Mendelian, we are building tools to help doctors find rare disease patients faster and diagnose them earlier. Join us/the conversation on hello@mendelian.co
