Psychopharmacology and mental retardation: a 10 year review (1990–1999)

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Abstract

We conducted a 10 year review of the literature pertaining to psychopharmacology and mental retardation. Studies were included or excluded from the review based on meeting one or more of the methodological criteria normally considered fundamental for sound scientific research. The vast majority of studies conducted in the last 10 years in this area had major methodological flaws. While a large number of medications were prescribed for various psychological disorders and behavior problems, most drug administrations were not based in science, were not evaluated appropriately, and generally did not follow best practices for treatment of persons with mental retardation. Very few medications prescribed were behavior or psychiatric symptom specific; that is, most medications were given to suppress a myriad of aberrant behaviors thus chemically restraining the individual in question. Practices such as these present serious problems for service providers due to the deleterious side effects of many psychotropic medications and the federal government’s intervention into the care-provision practices of developmental centers, community homes, and other living arrangements for persons with mental retardation. Implications of our review are discussed.

Introduction

Mental retardation is a pervasive condition characterized by low intelligence (IQ ≤ 70), concurrent deficits in adaptive functioning, and onset before 18 years of age (APA, 1994). The prevalence rate of mental retardation in the United States is estimated at 1–3%, but this number can vary considerably with age, race, sex, and socioeconomic status (Baroff, 1974). Approximately 25% of cases of mental retardation can be attributed to organic factors including chromosome disorders (Downs syndrome), gene defects (more than 3,000 noted to date), endocrine disorders (cretinism), prenatal infections (mumps; measles), and toxins (fetal alcohol syndrome). However, in almost 40% of cases no etiology of mental retardation can be determined despite detailed evaluation efforts (APA, 1994).

For many persons exhibiting mental retardation, aberrant behaviors or symptoms of psychopathology are the most salient features of the behavioral repertoire. Behavior problems such as aggression, self-injurious behavior, tantrums, property destruction, stereotypies, pica, and rumination are exhibited by upward of 40% of individuals in institutional placements (Baumeister, Todd & Sevin, 1993). Additionally, the prevalence of psychopathology in persons with mental retardation has been estimated at 4–6 times that of the general population (Borthwick-Duffy, 1994). As these conditions are readily observed by caregivers and professionals alike, they are often the primary focus of treatment and at the forefront of programmatic services for persons with the condition.

Though a wide range of techniques have been used to address problem behaviors/symptoms in persons with mental retardation, treatments can be generally classified into the broad categories of behavioral and pharmacological. Behavioral interventions have been well-documented in research as an effective means of treating aberrant behaviors (Scotti, Evans, Meyer & Walker, 1991). However, due to problems in implementing behavioral treatments (e.g., labor intensive and require considerable technical skill) and some agencies’ unwillingness to apply these methods, many treatment teams have turned to pharmacological interventions as the primary means of treating maladaptive behaviors. The same is true for symptoms of psychopathology making up various psychological disorders. Common practice is to treat most disorders with psychotropic medication alone, despite numerous studies suggesting that the combination of medication and behavioral treatments is most viable for treating many psychological disorders (Psychoses; Depression; Anxiety; Mania) (Sovner & Hurley, 1981).

Reviews of pertinent literature indicate that psychotropic medications are extremely overused with persons evincing mental retardation. The actual prevalence rates vary for individuals living in institutional versus community based settings. Prevalence rates for persons living in institutional settings have ranged from 50–66%, with most (40–50%) receiving traditional or atypical antipsychotics (Aman & Singh, 1983). For persons residing in community settings, prevalence rates have ranged from 7–74% and neuroleptic medications are the most widely prescribed in the population (Hill, Balow & Bruininks, 1985). Many reasons for high psychotropic drug use exist and include lack of staff, lack of access to professionals, and lack of command of appropriate assessment techniques. However, these or any other reasons are not sufficient to explain the large numbers of persons with mental retardation who take psychotropic medications.

Pharmacologic interventions have become some of the most widely used intervention techniques with persons evincing mental retardation despite the fact that many drugs are ineffective, suppress behavior generally, and cause a number of lasting, deleterious side effects (Baumeister & Sevin, 1990). The purpose of this paper was to review the literature on the use of drugs to control aberrant behavior and symptoms of psychological disorders in persons with mental retardation from a methodological framework often considered sound scientific practice by researchers in a number of areas. We believe this is an important topic given the lack of understanding about these drugs and the research that supports them in clinical practice. Therefore, we reviewed all published studies from the past 10 years that used medication to treat behavior problems or psychopathology. Baumeister and Sevin 1990, Baumeister et al 1993) conducted similar reviews of drug use in persons with mental retardation, and this work is intended to update their work in this area. After a brief introduction to these methodological issues, the efficacy of commonly used psychotropic medications will be evaluated across a number of behavioral and psychological disorders. Behavior problem areas discussed included self-injurious behavior, aggression, hyperactivity, stereotypies, tics, and various forms of psychopathology. A brief review of medication side effects follows. Finally, ethical issues concerning the use of psychotropic medications will be addressed.

Section snippets

Methodological issues

The major problem existing in most of the current literature on psychotropic medications in persons with developmental disabilities is that the bulk of the studies do not meet criteria considered methodologically sound. As a result, we identified a large number of variables that are considered essential in treatment efficacy research. An explanation of these variables follows.

1) Studies should contain a true experimental design with random assignment to treatment and placebo groups or

Self-injurious behavior

Self-injurious behaviors (SIB) are acts that result in physical injury to a person’s own body and are usually repetitive, rhythmic, and likely to produce pain in the absence of sensory impairment (Baumeister, Todd & Sevin, 1993). SIB is highest in persons with profound mental retardation. Approximately 10–20% of persons living in institutions for the developmentally disabled evince SIB, normally characterized by biting one’s self, hitting one’s self, or banging one’s head. SIB is positively

Aggression

Aggression represents one of the most serious behavior problems for persons with mental retardation. It has been estimated that approximately 30–55% of persons in state institutions for the developmentally disabled display physical aggression and is a frequent reason persons lose community placements (Baumeister & Sevin, 1990). Aggression is the primary reason that individuals are admitted or readmitted to institutional settings (Lakin, Hill, Haruber, Bruimins & Heal, 1983) and appears to be

Hyperactivity, stereotypies, and tics

We located 9 studies that included agitation, stereotypies, or motor/vocal tics as the measured dependent variable. Of the studies, 7 of 9 manipulated traditional and atypical antipsychotic medications along with various other medications as the drug of choice and the other 2 utilized imipramine in conjunction with various other psychotropic medications.

The studies in the review that attempted to treat stereotypies and hyperactivity with antipsychotic agents mostly yielded results that

Psychopathology

Persons with developmental disabilities display the full range of psychopathology including anxiety disorders, psychoses, unipolar and bipolar depressions, and dementia. In fact, studies report that psychopathology is 4–6 times more prevalent in these people versus the general population (Borthwick-Duffy, 1994). Despite these facts, these disorders still appear underdiagnosed in persons with mental retardation. As a result, the primary reasons why individuals should be receiving psychotropic

Side effects

Lastly, we reviewed 4 studies that comprehensively examined side effects and the part that various psychotropic agents played in their development, exacerbation, and dissipation. Each study reviewed contained individuals on a minimum of one antipsychotic agent in addition to a myriad of other medications. Although these studies, too, had flaws in their designs, the results were consistent for each study. Reductions in the medication regimes (namely the antipsychotic agents) brought about

Discussion

Intervention with psychotropic medication is, by far, the treatment of choice in clinical practice both in the community and in institutions for persons with mental retardation and behavioral or psychiatric disturbances (Baumeister & Sevin, 1990). With this fact in mind, we set forth to examine the methodological soundness of the drug research in this population. Our findings were startling and consistent with Baumeister and Sevin’s findings in 1990. Professionals continue to medicate

References (82)

  • D.K. Hilton et al.

    Imipramine treatment of ADHD in a Fragile X child

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1991)
  • J.P. Horrigan et al.

    Olanzapine in PDD

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1997)
  • T. Kastner et al.

    Verapamil and valproic acid treatment of prolonged mania

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1992)
  • C.J. McDougle et al.

    Risperidone treatment of children and adolescents with pervasive developmental disordersA prospective, open-label study

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1997)
  • R.W. Ricketts et al.

    Clinical effects of buspirone on intractable self-injury in adults with mental retardation

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1994)
  • R.W. Ricketts et al.

    Fluoxetine treatment of severe self-injury in young adults with mental retardation

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1993)
  • J.R. Scotti et al.

    Functional analysis and unsuccessful treatment of Tourette’s syndrome in a man with profound mental retardation

    Behavior Therapy

    (1994)
  • N.N. Singh et al.

    Effects of thioridazine and visual screening on stereotypy and social behavior in individuals with mental retardation

    Research in Developmental Disabilities

    (1993)
  • D.V. Taylor et al.

    Effect of naltrexone upon self-injurious behavior, learning, and activityA case study

    Pharmacology Biochemistry and Behavior

    (1991)
  • M.G. Aman et al.

    Pharmacological intervention

  • M.G. Aman et al.

    The Aberrant Behavior ChecklistFactor structure and the effect of subject variables in American and New Zealand facilities

    American Journal of Mental Deficiency

    (1987)
  • M.G. Aman et al.

    Haloperidol treatment with chronically medicated residentsDose effects on clinical behavior and reinforcement contingencies

    American Journal on Mental Retardation

    (1989)
  • Diagnostic and Statistical Manual-Fourth Edition

    (1994)
  • The American Psychological Association Code of Ethics, Standard 6.05b

    (1992)
  • Y. Barak et al.

    Disabling compulsions in 11 mentally retarded adultsAn open trial of clomipramine

    Journal of Clinical Psychiatry

    (1995)
  • J. Barnhill et al.

    Phenobarbital-induced disinhibition in the developmentally disabled. Case report

    Journal of Clinical Psychopharmacology

    (1997)
  • G.S. Baroff

    Mental RetardationNature, cause, and management

    (1974)
  • A.A. Baumeister et al.

    Efficacy and specificity of pharmacological therapies for behavioral disorders in persons with mental retardation

    Clinical Neuropharmacology

    (1993)
  • I.L. Beale et al.

    Effects of chlorpromazine and thioridazine on discrimination learning in children with mental retardation

    Journal of Developmental and Physical Disabilities

    (1993)
  • J.W. Bodfish et al.

    Diagnosis and fluoxetine treatment of compulsive behavior disorder of adults with mental retardation

    American Journal on Mental Retardation

    (1993)
  • S.A. Borthwick-Duffy

    Epidemiology and prevalence of psychopathology in people with mental retardation

    Journal of Consulting and Clinical Psychology

    (1994)
  • J.R. Brasic et al.

    Hyperkinesias in a prepubertal boy with autistic disorder treated with haloperidol and valproic acid

    Psychological Reports

    (1997)
  • J.R. Brasic et al.

    Clomipramine ameliorates adventitious movements and compulsions in prepubertal boys with autistic disorder and severe mental retardation

    Neurology

    (1994)
  • R.D. Buzan et al.

    Opiate antagonists for recurrent self-injurious behavior in three mentally retarded adults

    Psychiatric Services

    (1995)
  • M. Campbell et al.

    Naltrexone in autistic childrenBehavioral symptoms and attentional learning

    Journal of the American Academy of Child and Adolescent Psychiatry

    (1993)
  • M. Carpenter et al.

    Effects of antipsychotic medication on discrimination learning for institutionalized adults who have mental retardation

    Behavioral Residential Treatment

    (1990)
  • S.A. Cohen et al.

    Risperidone for aggression and self-injurious behavior in adults with mental retardation

    Journal of Autism and Developmental Disorders

    (1998)
  • N.A. Dartnall et al.

    Brief reportTwo-year control of behavioral symptoms with risperidone in two profoundly retarded adults with autism

    Journal of Autism and Developmental Disorders

    (1999)
  • P.A. Davanzo et al.

    Paroxetine treatment of aggression and self-injury in persons with mental retardation

    American Journal on Mental Retardation

    (1998)
  • J. Dent

    Catatonic syndrome following recovery from neuroleptic malignant syndrome

    Journal of Intellectual Disability Research

    (1995)
  • S.F. Diaz

    Mania associated with risperidone use

    Journal of Clinical Psychiatry

    (1996)
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