Rare Disease Week in Washington DC – which Narcolepsy Network President Keith Harper and I attended a few weeks ago – is the annual opportunity for advocates to make their case for federal support to aid people who have one of more than 10,000 conditions that relatively few Americans have.

Plenty of those diseases are far less prevalent than narcolepsy and even idiopathic hyposomnia. Take, for example, Gaucher Disease, a genetic disorder which affects digestion for 1 in 40,000 people, causing a buildup of fatty acids in the spleen, liver, bone marrow, and even brain. A young woman named Sasha – who has the condition, and was a fellow member, with Keith and I, of the New York delegation that visited Capitol Hill during Rare Disease Week – lobbied New York congresspeople and senators on a measure that would fund genetic testing of newborns when there’s suspicion they have a generic disorder such as Gaucher.

Gaucher Disease is among the conditions considered to be “ultra-rare” –  that is, affecting fewer than 1 in 50,000 people, or fewer than 10,000 sufferers in the entire U.S. Conditions considered to be merely “rare” are generally defined as affecting fewer than 200,000 Americans.

By those benchmarks, idiopathic hypersomnia clearly qualifies as a rare condition, and perhaps even an ultra-rare one. While research into the incidence of IH has yielded a wide range of prevalence, even the largest estimated incidence suggests there are no more than about 50,000 Americans who have IH. 

By contrast, narcolepsy is rare, by the benchmark cited above. With an estimated incidence of around 1 in 2,000, about 175,000 Americans have narcolepsy. That places our disorder at the high end of the incidence of 200,000 Americans that most medical bodies consider marks the upper end of what qualifies as a rare disease in the U.S.

Yet, arguably, narcolepsy is unquestionably rare if one also considers the realities of living as a person with narcolepsy. Many, even most, people with the condition who come to organizations such as Narcolepsy Network experience their first opportunity to meet others who live with the condition. That’s a powerful experience. As my then-teenage son told me at our first Narcolepsy Network conference, “I’ve finally met others who understand what my life is like. I don’t feel as alone anymore.” 

Further, consider the experience of being diagnosed with narcolepsy. All too frequently, during the Network’s online Zoom support group, a new participant describing their journey to diagnosis recounts doctors – sometimes, shockingly, even sleep specialists –  who misdiagnose narcolepsy because, as the patient often puts it to us, the doctor seems to know little to none about the condition.

The bottom line: The incidence of narcolepsy may barely qualify it as a rare disease in the statistical sense. But the lived experience of people with narcolepsy and IH makes these conditions very much align with rarity. Narcolepsy Network is proud to join fellow organizations at the annual event that seeks to make life easier for those who have rare diseases. 

Written by Paul Reynolds