Comorbidity of Attention Deficit Hyperactivity Disorder in Adults with Mental Retardation
Kibria, Gholam, Miller, Lewis, Educational Research Quarterly
This study investigated the comorbidity of ADHD in adults with MR. A sample of 57 MR adults, residing at an institutional setting, were screened for ADHD characteristics. The ADHD diagnostic characteristics listed in the DSM-III-R and the DSM-IV were used as the screening criteria. Subjects who met at least two of he three ADHD categories at p < .05 level were identified as having ADHD. The hypothesis that ADHD exists in the population of adults with MR was accepted. Recommendations for further research and implications for remedial education for adults with MR are discussed.
Although a great deal of controversy currently exists in the literature regarding the exact nature of Attention Deficit Hyperactive Disorder (ADHD), there has been, and continues to be, more emphasis on ADHD research (Goodman & Poillion,1992). While a number of studies have linked ADHD with other conditions, the comorbidity of ADHD with other conditions has not yet been established (Caron & Rutter,1991). In particular, there appears to be a paucity of research regarding ADHD in adults with Mental Retardation (MR). Most of the ADHD research has focused on children and adolescents; there is little research on ADHD in adults (Barkley,1990; Wender, 1990). The few studies that examined ADHD in adults have largely been uncontrolled and have methodological inadequacies (Braswell & Boomquist,1991).
There are indications in the literature that some individuals with MR exhibit behaviors that may be characteristic of other mental disorders, including ADHD (Handen, Breaux, Gosling, Ploof, & Feldman, 1990). In most cases, persons with MR might not be assessed in addition to the MR diagnosis for other possible etiologies of their behaviors (Caron & Rutter, 1991). The purpose of this study was to investigate the comorbidity of ADHD characteristics, as defined by DSMIII-R and DSM-IV, in the population of adults with MR.
Three ADHD categories were recognized in this study. The first ADHD category was identified under the DSM-III-R criteria. The second and third ADHD categories were identified under the DSM-IV criteria. Specifically, the DSM-IV identifies ADHD Predominantly Inattentive Type (PIT), and ADHD Hyperactive-Impulsive Type (HIT) as two separate categories. The ADHD diagnostic characteristics listed in the DSM-III-R and the DSM-IV were used to develop a 20 item survey questionnaire. The survey questionnaire was completed by Stockley Center staff, an Intermediate Care Facility for the Mentally Retarded at Georgetown, Delaware, in order to gather data on the subjects. Subjects were identified as ADHD if they met the diagnostic cutoff score at the p < .05 level or lower for at least two of the three ADHD categories used in this study.
For each subject in the study (n=57) four staff members were asked to complete a separate survey questionnaire. At least one of the surveying staff was a supervisor. At least two of the surveying staff were direct care workers. Staff members from both the day shift (6:00am2:00pm) and the evening shift (2:00pm-10:00pm) were represented in each subject's surveys. All of the surveying staff had worked with the subjects in question for at least six months. A subject was recorded as exhibiting an ADHD diagnostic characteristic if at least three of the four survey questionnaires had the corresponding questionnaire item marked "yes". The number of diagnostic characteristics exhibited by the subject was then examined to determine if the subjects met the diagnostic cutoff score for ADHD under the DSM-III-R and/or the DSM-IV. …