Chapter 5-Physicians, Guide to the Management of  HD

Psychiatric Symptoms not Belonging to a Specific Diagnostic Category

Patients with Huntington's disease may suffer from a variety of emotional symptoms which do not fit any specific psychiatric diagnosis, but may nevertheless be a source of distress and a focus of treatment including irritability, anxiety and apathy.

Some of these symptoms are related to the disease itself, and others can be seen as a response to changing circumstances, such as a patient who becomes anxious about going to the market because her involuntary movements attract attention.

Patients with HD may undergo personality changes, becoming irritable, disinhibited, or obsessional. In some cases these changes represent an accentuation, or coarsening of personality characteristics the person already had. Other times they will be a radical departure from the patient's usual state, which can be very distressing to families.

Families should be reassured, as patients can usually be helped by better communication, environmental interventions, and judicious use of medications.

Irritability

Irritability is a common complaint from persons with HD and their families. It is often associated with a depressed mood, but may also result from a loss of the ability of the brain to regulate the experience and expression of emotion.

Irritability in persons with HD may take the form of an increase in the patients' baseline level of irritability, or there may be episodes of explosiveness as irritable responses to life events become exaggerated in intensity and duration.

Other patients may not be irritable under most circumstances, but will develop a kind of rigidity of thinking which will cause them to perseverate relentlessly on a particular desire or idea, becoming progressively more irritable if their demands are not met. One woman, for example, insists on having ten or twelve varieties of juice in the refrigerator at all times and was markedly irritable during a recent visit to the clinic. Her husband had started the car to drive to the clinic and had refused to go back into the house to get her another glass of juice. Hours later she was still dwelling on it and kept interrupting the interview to say that she wanted to go home to have a drink.

Irritability in HD may have a variety of triggers and exacerbating causes. It is important to understand it in context and avoid premature use of medications.

One must first understand exactly what the informant means by saying the patient is irritable or agitated. Does the patient appear restless? Is the patient yelling or verbally abusive? Is there potential for violence? Many factors can precipitate an irritable episode, such as hunger, pain, inability to communicate, frustration with failing capabilities, boredom, and changes in expected routine.

Family members and caregivers should learn to respond diplomatically, appreciating the patient's irritability as a symptom. Confrontations and ultimatums should be avoided if the issue is not crucial.

The environment should be made as calm and structured as possible. Some families achieve this more easily than others. Family settings in which there are children and adolescents, unpredictable working hours, noise, or general chaos may lead to irritability and aggressiveness in persons with HD. Caretaker and family support groups can provide emotional support and are a forum for sharing strategies that members have found useful in their own households.

When irritability is severe, or enduring, or is expressed physically, patients are often described as agitated. A great deal of overtreatment, particularly with neuroleptics, stems from continuous use of a drug for an episodic problem. It is always necessary to revisit the situation and see whether the drug has actually reduced the frequency of outbursts. For episodic outbursts, success often results from combining drug therapy with a careful analysis of the context and precipitants of the outburst.

Nevertheless, we have found a number of medications helpful in treating enduring irritability. Patients may respond to antidepressants, particularly the SSRIs (sertraline, fluoxetine, and paroxetine) even if they do not meet all the criteria for major depression.

The optimal doses for treating irritability are not known but one should start at a low dose and increase gradually as in the treatment of depression (see table 13). These agents may be particularly useful when the irritability seems tied to obsessions and perseveration on a particular topic.

As in the treatment of depression, improvement may not occur for several weeks. Mood stabilizers such as divalproex sodium and carbamazepine have also been helpful and could be administered as outlined for bipolar disorder (see table 15).

Low dose neuroleptics may be helpful, particularly the newer, "atypical" ones which have fewer side effects. Long-acting benzodiazepines, such as clonazepam (Klonopin), starting at low doses, e.g. 0.5mg/day, have also been helpful.  The clinician must carefully monitor patients treated with these agents, as overdosing can lead to falls or aspiration.