Stages of Huntington’s Disease
People with Huntington’s disease (HD) follow a path of disease progression once symptoms begin. While patients can remain highly functional in the first years of the disease, independence gives way as symptoms get worse. This article discusses the ways in which HD symptoms change from one stage to the next, the degree to which individuals are independent in day-to-day life at each stage, and some common concerns along the way.
It is important to note that this article only describes the trends: each person has a different disease course. People begin the disease at different ages, some individuals pass through the different stages of HD more slowly or quickly than others, and symptoms may arise at different times for different people. In fact, even family members can have different disease courses. While people with a higher number of CAG repeats tend to decline more quickly, for reasons described here, there are many other genetic and environmental factors that may also play a role and are the subject of ongoing research. Some of these genetic factors are described here.
Table of Contents
Before any doctor would actually diagnose someone as having HD, the disease has already made a mark upon those who carry the genetic mutation. This phase, called the preclinical or prodromal phase, is currently of great interest to researchers, who are performing large clinical trials in order to better understand the changes people undergo prior to displaying symptoms of HD.
In one of these clinical trials, PREDICT-HD, doctors studied cognitive symptoms in 738 people who were HD-positive but had not begun to show symptoms, and compared them to 168 controls, who were mentally healthy and did not have the HD allele. Doctors estimated how far HD-positive participants might be from having symptoms that would warrant an official diagnosis of HD, based upon age and number of CAG repeats. The researchers report that people estimated to be 15 years or more away from a diagnosis of HD are similar to the controls in all but one measure; they are not as good on tests of emotion recognition. People estimated to be 9-15 years from diagnosis tended to score lower on a few tests of cognitive ability, and people estimated to be within 9 years of a diagnosis had significantly lower scores on tests of thinking, attention, memory, and emotion processing. The researchers found that up to 40% of people in the preclinical stages of HD have mild cognitive impairment, causing them to point out the importance of understanding the preclinical effects of HD. Their study suggests that further research is needed to determine if individuals who haven’t yet been diagnosed with HD might be helped by cognitive rehabilitation or cognitive-enhancing medication.
Behavioral symptoms are also likely to arise in people in the preclinical stage of HD. HD-positive people have a small increase in risk of mood problems in the 10 years before their diagnosis, and that risk increases dramatically in the year leading up to the diagnosis. Specifically, gene-positive carriers are significantly more likely to experience depression and irritability than the average person. Though this depression is due in part to the upsetting life changes associated with HD, it is also caused by the biological changes in the brain the disease brings about. One particularly worrisome aspect of this depression is the risk of suicide, which is much higher for people with HD. Suicide risk is highest in the pre-clinical and early stages of HD, particularly around the time of the genetic test.
A group of scientists in the European Huntington’s Disease Network wanted to understand what people with HD were most concerned about on a day-to-day basis, and interviewed 31 people in all stages of HD. For people in the pre-clinical stages of HD, the greatest concerns were social; they worried about how HD would affect family relationships, about a lack of support from friends and family, and about others’ attitudes towards HD. Social concerns were followed by emotional concerns. Those interviewed were anxious not only about their own emerging symptoms, but also about the changes that HD would bring. Legal concerns – such as planning insurance coverage and making up-front arrangements for future disabilities – played a small but noticeable role in their concerns, while cognitive and physical concerns were essentially unmentioned.
In the early stages of HD, symptoms become noticeable enough to warrant a diagnosis. Some symptoms – particularly cognitive and behavioral symptoms – may make it harder for people to work and perform at their usual level. However, at this stage, people are still able to maintain a fairly normal lifestyle and can generally continue to work, drive, and live independently.
Motor symptoms usually begin in the extremities of the body; people experience involuntary twitches in their fingers, toes, and face. Onlookers generally don’t notice these motions, or assume that they’re just nervous twitches. People in the early years of HD also experience a subtle loss of coordination, and may have more trouble performing complicated motions.
Cognitive symptoms also become noticeable in the early stages of HD, as it becomes more difficult for people to think through complicated tasks.
Behavioral symptoms can be fairly serious even when motor and cognitive symptoms are quite minor. Depression, irritability and disinhibition are common in the early stages, and some patients experience hypersexuality, which can cause problems in relationships
When interviewed about their day-to-day concerns about HD, people in the early stages of HD said they worried most about their physical difficulties; they were beginning to have twitches and jerks, and were starting to have trouble eating and sleeping. Cognitive symptoms presented the second biggest concern, as people were beginning to experience difficulty thinking through tasks that hadn’t previously been challenging. Emotional concerns also came up; patients reported low mood and motivation, and expressed anxiety about their emerging symptoms. Social concerns were mentioned, as those interviewed mentioned that relationships with family and friends were becoming more complicated because of HD, and they began to feel concerned about going out to socialize. Financial and legal concerns played a minor role.
By the middle stage of HD, people often lose their ability to work and drive, and might be unable to perform household chores. Eating can become challenging, as patients have trouble performing the complicated series of muscle movements needed to swallow. Speech becomes slurred, and walking becomes staggered. However, many people are still able to eat, dress, and take care of hygiene with some help. Physical therapists can help patients control their voluntary movements; speech pathologists can help patients deal with swallowing and speaking; occupational therapists can help patients deal with changes in their thoughts.
Motor symptoms become more serious and chorea – the involuntary dance-like movements of HD – is usually most severe during the middle stages of HD. People also have increasing trouble with voluntary motor tasks, and walking becomes more difficult; patients are more likely to fall or experience problems with balance in this stage. People with middle-stage HD also begin to have trouble swallowing, which leads to the weight loss that begins to become serious in this phase.
Cognitive symptoms become problematic, as patients have more trouble organizing information and thinking clearly. Often, patients can’t solve problems they were normally capable of working through.
Behavioral symptoms are similar to those experienced in the earlier stages. However, some people become increasingly apathetic as the disease continues, losing interest in activities that they used to enjoy. In the mid to late stages of the disease, many people have a decreased desire or ability to have sex.
Patients spoke at length about physical concerns – such as sleeping difficulties, balance, chorea, and slowness – that significantly interfere with day-to-day life. Physical problems are mentioned far more often than any other issue. Cognitive concerns are most often about slowness in completing tasks, trouble remembering information, and difficulty learning new things. Emotional issues arise, as patients are anxious about HD symptoms and the effect HD has on the family, and begin to experience mood swings and low mood. Social concerns revolve around maintaining romantic relationships, communication difficulties, and others’ attitudes and ignorance about HD.
By the late stage of the disease, people with HD require help in all aspects of life. They are generally unable to speak, and remain bedridden. Since it becomes more and more difficult to care for a patient as the disease progresses, patients often spend the last few years of life in a nursing home. Choking is a major concern; it becomes extremely difficult to swallow, so most late-stage patients need to be fed with a tube that is inserted surgically into the stomach or small intestine. Many patients have trouble urinating or become constipated, and some patients have trouble sleeping normally. HDSA has a detailed handbook for caregivers on the late stages of HD, found here, and for further caregiver resources, click here.
Motor symptoms are severe. By this point, chorea has usually stopped, although a minority of patients continue to experience severe chorea. Instead, patients generally have the greatest difficulty with voluntary movements, and often experience rigidity, dystonia, and bradykinesia.
Cognitive symptoms are debilitating, though patients can usually still understand speech and recognize loved ones.
Behavioral symptoms tend to improve slightly in the late stages of the disease. Depression, in particular, tends to fade in the middle and late stages of HD. Some doctors suggest that this is because patients in the late stages of HD have come to terms with the illness, though some believe this is because apathy is a very common symptom in the late stages of HD, and counteracts the effects of depression. Psychosis, a rare problem that causes people to have visual and auditory hallucinations, occurs in 3-11% of patients in the late stages of HD.
In the last years, people report that their physical symptoms are most pressing, as movement, maintaining body weight, sleep, and other physical problems outweigh other issues. Emotional concerns were mentioned, with most patients reporting low mood; few reported a lack of motivation, or anger or anxiety about HD symptoms. Social concerns mostly centered on lack of support from friends, family, and health professionals. Cognitive concerns were hardly mentioned.
End of Life^
In the last stages of HD, patients have difficulty thinking and communicating clearly, so decisions about their end-of-life medical care often fall to doctors and relatives. However, many people with HD have strong opinions as to how they would like their last years to unfold. An advance directive, also known as a living will, allows people with HD to plan their end-of-life medical care while they are still fully capable. An advance directive is a legal document with a set of instructions describing which medical procedures should or should not be performed in the terminal stages of the disease.
Advance directives for people with HD often address several issues. The “do-not-hospitalize” directive allows a patient to avoid hospitalization near the time of death, and is generally written by those who would rather die in a familiar setting such as their own home, rather than in a hospital. The “do-not-resuscitate” directive prevents the hospital from performing emergency life-saving procedures (such as CPR) if the patient’s heart stops beating, or if he/she stops breathing. Directives also often address tube-feeding, and sometimes express the wish that the patient’s brain be donated for research.
Advance directives are a difficult topic to bring up, but they do provide the patient with measures of control over and protection of their own life choices, while also relieving the patients’ relatives of the emotional difficulties of making life-or-death decisions for the patient. Moreover, relatives generally find solace knowing that they are carrying out the wishes of the patient. For more information on advance directives, click here.
Ultimately, people with HD die an average of 10-20 years after symptoms begin. Death is believed to be primarily from complications of the disease. The most common complication is aspiration pneumonia, in which patients get a fatal infection from unintentionally inhaling a piece of food. Suicide is the second leading cause of death. To read more about the complications of HD, click here.
1. Duff K, Paulsen J, Mills J, Beglinger LJ, Moser DJ, Smith MM, Langbehn D, Stout J, Queller S, Harrington DL; PREDICT-HD Investigators and Coordinators of the Huntington Study Group. Mild cognitive impairment in prediagnosed Huntington disease. Neurology. 2010 Aug 10;75(6):500-7. Epub 2010 Jul 7.
This technical article discusses cognitive changes in people with preclinical HD
2. Ho AK, Hocaoglu MB; for the European Huntington’s Disease Network Quality of Life Working Group. Impact of Huntington Disease across the entire disease spectrum: The phases and stages of disease from the patient perspective. Clin Genet. 2011 Jul 8.
This easy-to-read article discusses the concerns that most often come up for people in different stages of HD
3. Julien CL, Thompson JC, Wild S, Yardumian P, Snowden JS, Turner G, Craufurd D. Psychiatric disorders in preclinical Huntington’s disease. J Neurol Neurosurg Psychiatry. 2007 Sep;78(9):939-43. Epub 2006 Dec 18.
This medium-difficulty article discusses behavioral symptoms in people with preclinical HD
4. Klager J, Duckett A, Sandler S, Moskowitz C. Huntington’s disease: a caring approach to the end of life. Care Manag J. 2008;9(2):75-81.
This easy-to-read article goes over many aspects of end-of-life care for patients with HD
5. Nance M, Paulsen J, Rosenblatt A, Wheelock V. A Physician’s Guide to the Management of Huntington’s Disease. Third edition. HDSA: Huntington’s Disease Society of America, 2011
This is an easy-to-read manual on the science and management of Huntington’s disease.
6. Paulsen JS, Nehl C, Hoth KF, Kanz JE, Benjamin M, Conybeare R, McDowell B, Turner B. Depression and stages of Huntington’s disease. J Neuropsychiatry Clin Neurosci. 2005 Fall;17(4):496-502.
This medium-difficulty article discusses how incidence of depression changes as the disease progresses.
7. Pollard J, Best R, Imbrigilo S, Klasner E, Rublin A, Sanders G, Simpson W. A Caregiver’s Guide for Advanced-Stage Huntington’s Disease. Huntington’s Disease Society of America, 1999.
This easy-to-read handbook is a very helpful resource for caregivers taking care of people in late-stage HD
8. Simpson SA. Late stage care in Huntington’s disease. Brain Res Bull. 2007 Apr 30;72(2-3):179-81. Epub 2006 Nov 16. Review.
This easy-to-read resource has information about late-stage HD
9. “Stages of HD.” Huntington’s Disease Society of America. Web. 03 Aug. 2011. <http://www.hdsa.org/living-with-huntingtons/family-care/stages-of-hd.html>.
This easy-to-read webpage has a shorter description of the stages of HD, along with many useful documents with more details and advice for caregivers
10. Stout JC, Paulsen JS, Queller S, Solomon AC, Whitlock KB, Campbell JC, Carlozzi N, Duff K, Beglinger LJ, Langbehn DR, Johnson SA, Biglan KM, Aylward EH. Neurocognitive signs in prodromal Huntington disease. Neuropsychology. 2011 Jan;25(1):1-14.
This medium-difficulty article discusses the cognitive changes that are found in people with preclinical HD
11. van Duijn E, Kingma EM, van der Mast RC. Psychopathology in verified Huntington’s disease gene carriers. J Neuropsychiatry Clin Neurosci. 2007 Fall;19(4):441-8. Review. PubMed PMID: 18070848.
This medium-difficulty article discusses behavioral symptoms in people with preclinical HD
M. Hedlin, 8.23.11; recorded by B. Tatum, 8/21/12