Interim Results of CMT&Me Study Presented in Webinar

Depression, hand-and-finger weakness, and a lengthy delay from symptoms to diagnosis contribute to the burdens felt by people living with Charcot-Marie-Tooth disease (CMT).

Those are among the key findings of the ongoing CMT&Me study, recently presented in a webinar hosted by Vitaccess.

The entirely app-based study, sponsored by Vitacess (NCT03782883), was launched in 2018. It has more than 2,300 participants in the U.S., U.K., Germany, Italy, Spain, and France.

The study is being used to help researchers and clinicians better understand the unmet needs and burdens of people living with CMT by collecting information directly from patients, regarding the personal impact of their symptoms, how long it takes to receive a diagnosis, and the effect their condition has on their quality of life, among other items.

In contrast to patient-reported data obtained during clinical trials, CMT&Me seeks “real-world” data from people managing their conditions in everyday life.

Participants’ average age in this study is 47 years and nearly three-quarters (71%) are female.

Besides hand and finger weakness (reported as the most important symptom by 29% of volunteers), other top-ranked symptoms were difficulty walking (21%), weakness in the feet (13%), and fatigue (12%).

Disorders commonly co-occuring with CMT were depression (41%), anxiety (40%), gastrointestinal problems (22%), respiratory issues (18%), and “other medical conditions” (43%).

On average, participants described a 10-year span between first noticing their symptoms — typically about age 17 — and receiving a CMT diagnosis.

Mark Larkin, PhD, founder and CEO of Vitaccess, who presented the results, described this lag as “a very, very long time,” although it conforms to rates observed in published scientific literature.

Looking to specific countries, the U.K., which was the focus of the webinar, had a gap between onset and diagnosis of approximately nine years. By comparison, the U.S. averaged more than 10 years and Germany closer to 15 years.

Across all countries, diagnosis was mainly obtained through a doctor’s examination, followed by electromyography and genetic testing. Close to 60% of diagnoses also involved family history, while approximately 20% of diagnoses involved nerve biopsies or other tests.

There are six established types of CMT, with CMT1 — and the CMT1A subtype, in particular — being the most common. The CMT&Me study reflected this, with 60% of participants having CMT1A.

The next most prevalent were CMT2 (13%), CMTX (9%), and other subtypes of CMT1 (6%). Approximately 13% of respondents either had a different type of CMT or did not know their type.

Many questions in the study focus on how CMT affects quality of life.

Pain, sleep disturbances, and fatigue all showed high marks, on average, for having the greatest quality-of-life impacts, as did cramps and falling.

Nearly 82% of respondents reported having cramps at least once per week, and 15% reported experiencing them daily. Participants expressed a “high level” of concern, regarding falling during social and physical activities both in and out of the home.

Vitaccess saw the concern with falls as something that should be investigated more closely and, following discussion with its scientific advisory board, added a fall tracker to the app, enabling users to document their falls as they happen.

“One of the benefits of [these types of digital studies],” said Larkin, is that “it’s possible to … look at what the data are like and adapt the strategy that one has accordingly.”

The study also contains questions related to individuals’ lifestyle, such as smoking and exercise habits.

Most CMT&Me respondents (82%) reported not smoking. A further 85% had either never drank alcohol or consumed less than one unit per day. Nearly two-thirds of patients (68%) eat fruits and vegetables daily, and 58% exercise at least once a week.

The app also asked people what treatments they used. These included medicines, physical therapy, devices such as orthotics, and surgical procedures.

Three-quarters of respondents took pain medication, 36% took medicines for depression, and 16% took them for anxiety. More than half of the participants (53%) used used insoles in their shoes, 51% walked with ankle or leg braces, and 36% used walking sticks.

Finally, the study assessed the patients’ contact with healthcare professionals, asking them how many times they had visited certain providers over the past year.

Family practitioners and neurologists were most frequently visited across nearly all countries. Germans predominantly saw neurologists followed by orthotists, although the difference between these and family doctors was small, and rehabilitation specialists were sought more often in Italy and Spain, compared to other countries.

“Many thanks to all of those people who have contributed to this study so far,” Larkin said. “To have, you know, close to 2,400 participants who engaged with the study really has given us a fantastic opportunity to explore the impact of CMT on patients across these different countries.”