A boy stands behind a model of DNA. Paul Gilham / Getty Images

To most people, Q93.51 would seem like an arbitrary collection of letters and numbers. But for Terry Jo Bichell, it represents an important victory, and the hope of something better for her son Lou.

Lou, 19, is the youngest of five siblings, and the only one born with Angelman syndrome—a genetic condition characterized by a happy, excitable demeanor, but also by absent or minimal speech, delayed development, movement problems, and a high risk of seizures. It’s estimated that between 1 in 12,000 to 1 in 20,000 people have the condition, although exact figures are hard to come by since many are misdiagnosed with autism or cerebral palsy.  

In the past, when Lou and other Angelman patients went to see their doctors, they would be listed under the medical code Q93.5. That code and others like it come from the International Classification of Diseases—a master list of health problems, as defined by the World Health Organization. These codes might seem like bureaucratic arcana, but they have serious effects on people’s lives. Researchers can use them to interrogate large databases and find out how many patients have a particular disorder, what secondary problems they experience, what treatments they typically receive, how many times they’re admitted to the hospital, and more. Insurers use them to decide what treatments should be reimbursed. “They’re like social security numbers for diseases,” says Bichell.

The problem was that Q93.5 was a dumping ground for hundreds of genetic disorders. The Q means that you have a birth disorder, caused by problems in your chromosomes. The 9 means that it’s not a condition that affects a specific organ system—say, nerves or gut. The 3 means that it’s not Down’s, Turner’s, or other well-known syndromes, and that the underlying genetic problem doesn’t affect either the X or Y chromosome. The 5 means that you’re missing part of a chromosome, but not parts that are covered by other codes.

That’s where Angelman sat—in a miscellaneous bucket, three times over, alongside very different disorders that it had nothing in common with, save that they didn’t quite fit anywhere else. “It was completely meaningless,” says Bichell. And it consigned Lou and others like him to a kind of medical anonymity. By contrast, the specific code for autism—F84.0—“opens a lot of doors,” says Bichell. “Children can have behavior therapy and all kinds of things that are reimbursable. But for Angelman syndrome, there was no code, so having that diagnosis didn’t automatically connect to potential treatments.”

That’s no longer the case. After a year of effort from Bichell and others, Angelman syndrome is getting its own specific code—Q93.51. That single extra digit at the end means everything. It’ll make it easier to understand the lives of people with the condition, to recruit them for clinical trials, and to develop better ways of caring for them.  

Bichell was once a documentary filmmaker, and then a nurse and midwife. But when Lou was born and diagnosed, she shifted her focus to studying Angelman syndrome and developing treatments for it. She raised funds for research, earned a PhD in neuroscience, and became the director of an alliance that ensures clinical trials for new Angelman treatments are done rigorously and collaboratively.

Her foray into the esoteric world of medical codes had a morbid origin: “I worried about what my son would die from,” she says. “We heard lots of scary stories about kids drowning because they wander off and have a fascination with water. But there was no data.” Without medical codes to link Angelman syndrome with accidents, surgeries, hospital admissions, or anything else, Bichell was lost. She put together a Facebook page and collected stories from people who knew an Angelman patient who had died. “I collected over 200 cases,” she says. “But I couldn’t make any conclusions from that.”

Last spring, with help from Angelman experts, Bichell wrote an application to grant the disorder its own ICD code, and sent it to the National Committee on Vital and Health Statistics, which administers the codes in the U.S. She bolstered it with letters of support from universities, pediatrician associations, autism foundations, and pharmaceutical companies. Finally, in September, she appeared before the committee to make her case, along with Wen Hann Tan who studies Angelman at Boston Children’s Hospital, and Raquel Cabo from Ovid Therapeutics, which is developing treatments for the disorder. Two weeks ago, they got their code.

To an extent, they could have waited. The new code modifies the 10th iteration of the ICD in the United States, and the 11th, which was recently released by the World Health Organization, does have a unique code for Angelman. But the U.S. has been traditionally slow to adopt these guidelines, and may then modify them, Bichell says. “We may be stuck with the ICD-10 for ten more years, even though the rest of the world has moved on.” And that would be unacceptable because research into the disorder is progressing fast. “Having the code is even more important now because we have great treatments that are in clinical trials,” Bichell adds. When the U.S. eventually adopts the new edition, researchers should be able to link up data tagged with the new U.S. Angelman code with the code from the 11th ICD.

Ovid Therapeutics, for example, is running a clinical trial of 88 Angelman patients to see if a drug called gaboxadol can help reduce their behavioral, movement, and sleep problems. The first results are expected in the fall. “Having a specific code really helps us when we’re searching for information to inform our development programs,” says Amit Rakhit, Ovid’s chief medical officer. “And once we get to a commercialized agent, the code will help us to understand [the drug’s] impact on healthcare systems around the world.”

Meanwhile, Bichell is helping other organizations, who represent people with rare genetic disorders, to navigate the opaque world of medical codes. The Foundation for Prader-Willi Research, for example, is also applying for a specific code—one that actually existed in the 9th iteration of the ICD but was dropped from the 10th. Bichell believes that every rare disorder should ultimately get its own code, and it’s hard to argue with that kind of specificity given that there are ICD codes  for being bitten by an orca, for prolonged stays in a weightless environment, and for being sucked into a jet engine.

Once those codes exist, the challenge is getting doctors to be aware of them, and use them. “You have to market the number,” Bichell says. “I changed my Facebook [photo] to Q93.51. As soon as I put it out there, all these moms were saying: Okay, time to get the tattoo!”

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