The Patient with Mental Retardation

by Hauser MJ
Ratey JJ

I. Mental retardation (MR) refers to deficits in cognitive and adaptive functioning with onset during development. MR is not a specific diagnosis; there are diverse etiologies and in many cases the etiology is not known. MR is a persistent condition and therefore is not, by itself, a cause of emergency department visits. However, the presence of MR may make individuals vulnerable to environmental disruptions, and it complicates evaluation, management, and treatment planning whatever the acute intercurrent condition. When individuals with MR come to the emergency department there are special considerations to take into account, which are addressed in this chapter.

Diagnosis. In general, the mentally retarded person has substandard cognitive functioning as measured by an IQ test and substandard adaptive functioning in such spheres as interpersonal relationships, daily living skills (grooming, hygiene, dressing, self care, safety and self preservation), managing vocational and/or recreational aspects of life. Three criteria must be met for a diagnosis of mental retardation.

  1. IQ (a measure of cognitive function based on verbal and performance measures) of 70 or below.

  2. Deficits in adaptive functioning.

  3. Onset of the disorder before age 18.

Severity is judged by the degree of cognitive dysfunction as measured by IQ.

  1. Borderline intellectual functioning: IQ greater than 70.

  2. Mild MR (85% of cases): IQ 50-55 to 70.

  3. Moderate MR (10%): IQ 35-40 to 50-55.

  4. Severe MR: (3.5%): IQ 20-25 to 35-40.

  5. Profound MR (1.5%): IQ below 20-25.

  6. Unspecified MR: Severity undetermined.


  1. Prevalence. Depending on whether mild MR is included, 1-3% of people have MR.

  2. Sex ratio. MR is approximately 1.5 times more common in males than in females, possibly due to X-linked genetic conditions.


  1. There are over 250 known causes of retardation.

  2. In only approximately 25% of people with MR is there a known biological cause; in the other 75% of cases, the cause is unknown or due to factors other than biological ones, such as psychosocial factors.

  3. Known etiologic factors include:

    Chromosomal abnormalities.

    Genetic defects.

    Perinatal factors (e.g., anoxia).

    Acquired childhood diseases.

    Environmental factors (e.g., lead toxicity, psychosocial factors).

II. Approaching the patient with MR

There are many misconceptions about individuals with MR that may adversely affect care.

  1. It is sometimes believed that people with MR cannot have mental illness; in fact they are vulnerable to the full range of mental illnesses.

  2. Too often individuals with MR are treated as if they do not have normal feelings and emotions. Of course they do; they are capable of the full range of human emotions. They can be vulnerable and sensitive, and in the emergency setting they can be frightened.

  3. It is sometimes thought that individuals with MR are not affected by changes in their environment. In fact, with a diminished capacity to understand what is happening to them, people with MR may have heightened reactions to such events as staff turnover or other changes in their residential or vocational programs, new housemates, or illnesses in family members. These are all stressors that can precipitate behavioral decompensation. Indeed, being evaluated in the emergency department is itself an event that can have dramatic behavioral consequences.

  4. It may not be recognized that people with MR may have substance abuse problems, particularly with alcohol.

  5. There is controversy over the use of antipsychotic drugs (neuroleptics) in people with MR. Some caretakers believe that these drugs should never be used. Of course antipsychotic drugs have serious side effects and their misuse or overuse (e.g., as a substitute for potentially effective psychosocial interventions) is poor practice. However, when prescribed appropriately (e.g., for psychotic disorders or for severe behavioral disturbances that fail to respond to less restrictive treatment modalities), antipsychotic drugs may have significant beneficial effects.

General approach to the patient and the patient's regular caregivers

  1. Conducting the evaluation

    Evaluate the patient in a safe, private, quiet place. Being observed and overheard by other patients and staff in the emergency department can be frightening, distracting, or overstimulating. Some individuals enjoy the attention they get for disruptive behaviors (e.g., throwing a tantrum), especially when other patients, families, and staff comprise an audience. Using a quiet and private place will enhance the evaluation. While noise and distractions are inevitable in the emergency setting, they complicate the assessment.

    Conduct the evaluation promptly. The patient with MR may have a diminished capacity to cope with waiting. Having to wait may cause additional behavioral deterioration, which may make the subsequent evaluation and any intervention more difficult.

    When possible, invite familiar staff or family to keep the patient company; their presence is likely to facilitate the evaluation. MR patients benefit from predictability; the presence of a familiar staff member may foster this. Even more important, the patient's regular caregivers will be needed to provide history.

    Explain any procedures simply and clearly.

  2. Role of the psychiatrist

    In the approach to the patient with MR, the psychiatrist must use his or her training in both medicine and psychiatry. This is because people with MR brought to the emergency department because of a behavioral disturbance or change in mental status may actually have an underlying medical or surgical problem that has not previously been identified. The psychiatrist must then make appropriate medical or surgical referrals. However, a further role is often warranted: The psychiatrist may have to act as a representative for the patient-for example, helping other physicians understand the patient's behavior-so that the patient receives appropriate evaluation and treatment.

    When the problem is behavioral rather than medical, it must be ascertained whether the patient has a primary psychiatric disorder or whether the problem has resulted from a change in the patient's environment. For example, if a patient is profoundly upset over placement with a new roommate, effective intervention requires attention to the living situation rather than simple administration of a sedative.

    Whether the recommendation involves administration of a psychotropic medication, a change in the patient's living arrangement, or some other psychosocial intervention, the psychiatrist must not only take the acute problem into account but also the patient's relationship to long-term caregivers. Thus the psychiatrist must use an interdisciplinary team model, which is the model for most long-term care of individuals with MR.

  3. The concerns of the referring caregiver must be taken into account.

    It is useful to consider the context of the decision to seek emergency department consultation. Often, the decision is made when caregivers are "at the end of their rope" and feel as if they can no longer cope with the patient. Often the last thing that caretakers of mentally retarded individuals want is to involve medical personnel or a hospital in their client's care. They often have put an evaluation off until the problem is far advanced, and they come in grudgingly.

    Despite their distrust of physicians and hospitals, caregivers may also have the expectation that the emergency department staff has miracle workers who will solve the problem, either by taking the patient off their hands or by telling them what to do. Such mixed feelings may lead to hostility and disappointment in the caregivers when problems are not magically solved. The psychiatrist must be aware of the possibility of such feelings and therefore avoid playing the role of magical rescuer. Even worse is saying that nothing can be done to help.

    Long-term caregivers generally refer to individuals as clients rather than patients. It may be helpful to respect their terminology.

    Although it is dangerous to generalize, some characteristics of the caregivers who may be bringing in the patient are:

    1. They have a deep involvement in the client's life and care a great deal about that client.

    2. They often have a philosophical (or ideological) perspective that medication is toxic and even poisonous.

    3. They may mistrust doctors.

    4. Often, their entire career-their raison d'etre-is based on the desire to help their clients without medication and without involving psychiatry.

    Some individuals with MR have been cared for by families rather than professional staff. Such individuals may need referrals for appropriate services.

III. The emergency evaluation

People with MR are brought to the emergency department for a variety of reasons:

  1. A change in mental status-for example, confusion, agitation, or psychotic symptoms.

  2. A change in mood, energy, or sleep patterns.

  3. A change in behavior, such as a new onset of aggressive behavior toward others or self-destructive thoughts or behavior (e.g., head banging).

  4. New physical complaints, such as pain, or behaviors, such as agitation, that might signify physical illness. Sorting out such problems can be extremely challenging. A normal person might say, "My stomach hurts," whereas a retarded person might become irritable and attack the staff when he or she has abdominal pain.

The "disappearing" problem. Often, the patient's behavior changes when brought to the emergency department. For example, if the patient was aggressive in his residence, by the time he arrives at the emergency department he might have calmed down. It is obviously difficult for the clinician to evaluate a behavior that is no longer in evidence. Indeed, in a busy emergency department, only acute problems get serious attention. The emergency staff may say, "Well, he's not aggressive anymore, so take him home." The regular caregivers may fear a return of the aggression, however. It is therefore important to assist these caregivers by evaluating the underlying problem, assessing the likelihood of a recurrence, and suggesting appropriate interventions.

Assessment of the problem

  1. A thorough history must be obtained, including history from caregivers. Information must be obtained not only about the current problem and the events leading up to it but also about the patient's usual level of functioning.

  2. Medical illness must be ruled out. This is especially important in mentally retarded individuals because of limitations in their capacity to communicate. However, people with MR frequently communicate by their behavior, such as increased irritability or impulsivity, or outbursts of aggression. Such behavioral change may represent constipation (perhaps the most common medical cause of agitation), a dental problem, a urinary tract or other infection, or other medical problem.

  3. It is important to consider medication side effects as a possible cause of behavioral deterioration.

    Benzodiazepines are commonly used as sedatives and hypnotics. Benzodiazepines with long half-lives (see Appendix III) may accumulate, especially in older individuals, and cause drowsiness and mental clouding. Short-acting benzodiazepines may cause interdose rebound symptoms, with marked worsening of anxiety just prior to scheduled doses (see Chap. 18). Inarticulate individuals with such side effects may cause a very confusing picture. In autistic individuals, benzodiazepines may cause ataxia

    Anticonvulsants may produce excessive sedation. Phenobarbital may be sedating; occasionally it may have paradoxical disinhibiting effects.

    Antipsychotic drugs. Individuals with MR are prone to the same side effects as anyone else, such as parkinsonism and akathisia. It is particularly important to recognize akathisia because it can present as worsening agitation and lead to an unnecessary extensive workup. Even worse, misdiagnosis of akathisia may lead to an inappropriate increase in the neuroleptic dose. As with all patients, excessive doses of antipsychotic drugs can interfere with alertness and overall performance. Therefore it is important to maintain individuals with MR on the lowest possible dose of antipsychotic medication to control psychotic symptoms or target behaviors. Reducing dosages can lead to problems such as agitation, behavioral deterioration, and worsening of abnormal involuntary movements, which may represent transient withdrawal dyskinesias. Therefore dosage reductions must be slow and careful.

    Other medications, easily forgotten in the history, may cause psychiatric symptoms. These include antihypertensive drugs, eyedrops for glaucoma (often beta-adrenergic blockers), and allergy medications (almost all anticholinergic).

  4. It is important to conduct a full physical examination. This must be per-formed systematically and patiently. The presence of familiar staff may help calm the patient. In some emergencies, when a patient cannot comply with examination, sedation may be necessary.

  5. Appropriate laboratory tests depend on the differential diagnosis.

IV. Treatment and disposition planning

Acute treatment considerations

  1. Consider a need for changes in the patient's immediate environment. Are there addressable stressors that triggered the decompensation?

  2. Assess the need for increased supervision of the individual's activities.

  3. If necessary, suggest a consultation for behavioral management strategies; these are often designed to guide the actions of the staff.

  4. Whatever psychosocial treatment recommendations are made, it is critical to promote consistency of staff behavior toward the patient and consistency of the patient's environment.

  5. Psychopharmacologic treatment should be reserved for appropriate target disorders and syndromes.

Medications should not be administered to the patient simply to diminish staff anxiety. In such cases skillful management of staff expectations are needed. For example, the clinician can acknowledge that it would be ideal to have a medication that would effectively treat these symptoms without producing serious side effects, but such a medication does not exist. It is important to address possible environmental causes of problem behaviors. This will help the staff recognize the context in which such behaviors occur and make appropriate adjustments rather than demanding inappropriate prescription of antipsychotic drugs.

The danger of prescribing antipsychotic drugs for nonspecific sedation is that they will be continued indefinitely, resulting in serious side effects for the patient. If nonspecific sedation is clearly needed, short-term administration of a benzodiazepine is a better choice.

Medications are often needed for longer-term treatment of depression, obsessive-compulsive disorder, psychotic disorders, and attention deficit disorder. In addition, pharmacologic treatment may be useful in treating certain symptoms that have not responded to reasonable environmental interventions. These circumstances include short-term treatment of sleep disturbances (e.g., with a benzodiazepine), treatment of impulsivity or aggression (e.g., with a series of empirical trials with buspirone, beta-adrenergic blockers, or carbamazepine), treatment of agitation (e.g., with a benzodiazepine), and treatment of self-injurious behavior. In general, doses of medications for individuals with MR are no different from doses used for other individuals of the same size and age.

Determination of responsibility for subsequent care. Most patients are al ready part of an existing caretaking system to which they can return. At times, the existing caretakers are not capable of caring for the person during the acute episode, so the emergency staff must help develop an alternative plan. Such a plan may include temporary acute hospitalization. However, appropriate acute treatment coupled with long-term treatment recommendations may make it possible for the individual to return to his or her prior environment.

  1. Create a data collection mechanism to assist the patient's regular caregivers in observation, recording, and communication of pertinent information.

  2. Recommend any additional appropriate tests.

  3. Articulate triggers for follow-up either by telephone or a repeat visit to the emergency department.

  4. If appropriate recommend a meeting with other clinicians involved in the I person 5 care-for example, the primary care physician, residential caregivers, vocational and/or day program staff, medical specialists, and behavioral specialists.

V. Legal issues

Informed consent. The diagnosis of MR does not by itself imply that the retarded person cannot consent to his or her own treatment (see Chap. 10). However, in many cases the competence of the individual to consent may be paired; in such cases there may already be a guardian or the establishment of guardianship may have to be considered. Competence must be assessed case by case basis. In the emergency setting, life-threatening problems warrant emergency treatment, even in the absence of informed consent. If someone obviously not competent, a long-term caregiver or family member should be asked to consent to the evaluation and treatment.

Guardianship. When there is a legal guardian, authorization for evaluation and treatment must be obtained from the guardian except in the case of life threatening emergencies.

Mandated reporting of abuse of disabled persons. Many states have statutes that require medical personnel to report a suspicion of abuse. Clinicians should become familiar with their own state's requirements, laws, guidelines, and standards of practice.

Consent decrees. Many states have entered into binding legal agreements as a result of lawsuits initiated by plaintiffs who wanted to improve the quality of care delivered to people with MR. These consent decrees may mandate specific degrees of quality of treatment. Again it is useful to become familiar with state requirements, laws, guidelines, and standards of practice.

Selected Readings

Gualtieri, C. T. Neuropsychiatry and Behavioral Psychopharmacology. New York Springer, 1991.

Ratey, J. J. (ed.). Mental Retardation: Developing Pharmacotherapies. Washington, D.C.: American Psychiatric Association Press, 1991.

Sovner, R. (ed.). The Habilitative Mental Healthcare Newsletter. Psych-Media Inc.

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