Patients who suffer from a rare disease experience higher levels of anxiety, stress, and depression. That is why many researchers and healthcare organizations who treat and support these patients are turning their attention to mental health. It is an important connection for patients, their families, and the greater medical community to be aware of and to understand.
What makes a disease rare? Depends on who you ask.
Rare diseases are defined by their prevalence rate; i.e., the disease rarity designation is a function of the number of occurrences of the disease when compared to the size of the population of the country. For example, according to Orphanet, an information source sponsored by several European Union (EU) Institute of Health, the EU Regulation on Orphan Medical Products designates a rare disease as that which effects not more than 1 person per 2,000 in the European population. (1) As for the U.S., the Orphan Drug Act of 1983 classifies a disease as rare if the rate is 7.5 per 10,000 people, or less than 200,000 U.S. residents per year.(2) Japan defines rare as affecting fewer than 50,000 people in its population; Australia fewer than 2,000 in its population. (3)
So what’s going on with patients?
Getting to the root of why so many patients with rare diseases suffer from mental health issues requires a look at the bigger picture. There are several contributing factors.
The serious nature of the disease itself. Most rare diseases are chronic, highly complex conditions. More often than not, they are also quite serious so the poor prognosis they carry has an understandably adverse effect on mental health.
Inadequate support. Since so few people are affected by a given rare disease, patients come up against a scarcity of information, and an inadequate support network. This can lead to patients “shrinking their life to fit the disease,” meaning they withdraw from others and isolate from society to varying degrees.
An awareness vacuum. We like to think our doctors know everything, but there are many rare diseases most healthcare practitioners have never heard of because they simply do not come across them very often, if ever. This means they don’t know the signs and symptoms to look for. Some rare disease patients can suffer symptoms for 10, 15, 20 years or more without being accurately diagnosed. That is a long time to live with debilitating symptoms no one understands. Patients not receiving the right treatment at the right time and lacking reassurance from the healthcare system are the main causes of extreme stress, hopelessness, and mistrust in the clinician.4]
The day-to-day realities. Multiple visits to different clinics, mobility issues, social isolation, ambiguous future prospects, dependency on others for help in performing simple tasks, or insensitive family and friends are some of the realities that can impact the lives of patients facing rare diseases. These influences, while varying widely in scope and impact may include anxiety, stress, low mood, emotional exhaustion, and suicidal thoughts, all of which have been identified in the rare disease population can all have adverse effects on a patient’s life. A diagnosis is very powerful because it essentially sums up a huge amount of information and conveys a cause, clinical course, and treatment. “Often it can predict that you will get better, and it provides information on how long it will take to get better. This cannot necessarily be said about rare disease diagnosis because very little might be known about a particular disease.” (5)
What can be done?
The good news is there are several identified measures available to patients, in coordination with their healthcare practitioners, to help them navigate life with a rare disease.
A large scale 2013 survey reported that 90% of US participants and 91% of UK participants were anxious about the prognosis for their disease, which makes them feel uncertain about their future. One of the most significant issues causing anxiety and stress is a delay in receiving a correct diagnosis. (5) A comprehensive study by Rare Disease UK showed that only one out of seven patients suffering from a rare disease receives adequate mental support. Their conclusion: Psychological support should be an integral part of the medical treatment and should be regarded as a fundamental aspect of the treatment regime. 
In 2018, the All-Party Parliamentary Group of the United Kingdom conducted an inquiry on rare diseases and set out these recommendations:
- Provide sufficient knowledge and skill to clinicians to exhibit an understanding of the emotional difficulties faced by people with a rare disease and to sensitively deal with incumbent mental health issues
- Routinely expose patients and caregivers to psychological support training for rare diseases
- Provide multifaceted rare disease services to patients, including access to mental health and evaluation of mental health status and requirements. 
The exact relationship between rare diseases and a patient’s mental health is complex and still not fully understood although more recent work is underway. Yet, it is critical that healthcare professionals not mistake any issues as psychosomatic. This implies that the behavior of care providers and others in the patient’s orbit should change so that patients are not reluctant to seek psychological help.
There is Hope
Researchers are working tirelessly to understand the characteristics of rare diseases while around the world an increasing number of organizations offer community, resources, and other support. Patients, their families, caregivers, and the international healthcare community all have more options than ever before to find the help and guidance they need, including:
Resources | Canadian Organization for Rare Disorders – Includes International Organizations for Support for Rare Diseases.
- The Portal for Rare Diseases and Orphan Drugs. https://www.fda.gov/industry/designating-orphan-product-drugs-and-biological-products/orphan-drug-act-relevant-excerpts
- About Rare Diseases. AOP Orphan. https://www.aoporphan.com/ae_en/rare-diseases
- Rare Disease FAQ. NIH. Jan, 2020. https://www.genome.gov/FAQ/Rare-Diseases
- Ibrahim M. How Rare Diseases Can Impact Mental Health. Racontuer. July, 2019. https://www.raconteur.net/healthcare/mental-health/rare-disease-mental-health-problems/
- Davies, Nicola, PhD. Rare Diseases: A Psychiatric Concern?. Psychiatry Advisor. March 4, 2019. Rare Diseases: A Psychiatric Concern? – Psychiatry Advisor
- The Rare Reality – An Insight into The Patient and Family Experience of Rare Disease. 2016. http://www.raredisease.org.uk/media/1588/the-rare-reality-an-insight-into-the-patient-and-family-experience-of-rare-disease.pdf. Accessed 10 Nov 2016.
- Living with A Rare Condition: The Effect on Mental Health. Rare Disease UK. May, 2018. https://www.raredisease.org.uk/wp-content/uploads/sites/7/2018/07/living-with-a-rare-condition-the-effect-on-mental-health-pdf.pdf