Experts are observing a notable increase in diagnoses of Huntington's disease, a progressive and fatal genetic disorder that damages nerve cells in the brain. This condition, which has been described as a combination of dementia, Parkinson's, and motor neurone disease, has seen its prevalence double since the 1990s, according to multiple studies. Approximately 7,000 individuals in Britain are currently living with the disease, and about one in ten patients die by suicide.
Research published in the European Journal of Neurology in 2022 indicated that from 2000 to 2018, the prevalence of Huntington's disease rose from 4.3 cases per 100,000 people to 9.2 per 100,000. This trend follows a 2013 paper that identified a doubling in diagnoses since the 1990s. In specific regions, the increase has been more dramatic; a 2021 study reported a 50% jump in Northern Scotland over the past 30 years.
Huntington's disease is typically inherited, with children of an affected parent having a 50% chance of inheriting the mutated huntingtin (HTT) gene. The disease usually manifests after the age of 30 and is currently incurable, with an average life expectancy of 15 to 20 years post-diagnosis.
Dr. Daniel van Wamelen, a clinical lecturer in neuroscience at King's College London, suggests that the rise in diagnoses is likely attributable to enhanced methods for detecting the genetic marker, rather than a true increase in the disease's incidence. The identification of the HTT gene in 1993 has facilitated easier genetic testing.
However, Dr. van Wamelen also notes that many cases remain undiagnosed due to a "fear of finding out" and a perceived stigma surrounding the disorder. The genetic nature of Huntington's means that individuals with an affected parent face a difficult decision regarding genetic testing. A 2019 study in Clinical Genetics found that two-thirds of individuals who opted not to be tested cited the absence of an effective treatment or cure as their primary reason.
Dr. van Wamelen further explained that the disease's clear "motor manifestations," which can include changes in behavior, disinhibition, and involuntary movements, may contribute to a lack of public understanding and compassion. Symptoms can also encompass obsessive behaviors, delusional thoughts, lack of self-awareness, difficulty concentrating, memory problems, depression, and anxiety. In later stages, patients may experience swallowing and speaking difficulties, weight loss, and muscle stiffness.
While research into potential treatments is ongoing, including work by Chinese researchers in 2019 who identified compounds that bind to and destroy the mutant protein, the disease remains incurable. Complications such as pneumonia are the most common cause of death among individuals with Huntington's disease.