The Massachusetts General Hospital studies of gender influences on attention-deficit/hyperactivity disorder in youth and relatives.

With the single exception of SUDs, no statistically significant gender-by ADHD interactions were identified in the multiple, outcomes evaluated. These results suggest that with the exception of SUDs, ADHD expresses itself similarly in boys and girls relative to comparison subjects of the same gender, indicating that ADHD-associated impairments are correlates of ADHD in both genders. Gender differences, such as the higher prevalence of symptoms of inattention and lower rates of comorbidity with disruptive behavior disorders, major depression, and learning disability, were identified among the ADHD subjects. Because these differences were caused by the main effects of gender rather than effect modification of ADHD by gender, these findings indicate that girls were at the same relative risk for these adverse outcomes as boys, but that female gender resulted in a different clinical presentation than that affecting boys.The single statistically significant gender-by-ADHD interaction identified was the association between ADHD and SUDs (alcohol or drug abuse or dependence). ADHD in females was a more serious risk factor for SUDsthan it was in males was an unanticipated and surprising finding. In light of ongoing concerns regarding ADHD as a putative risk factor of SUDs [12],this finding may indicate that girls are particularly at risk in early adolescence. Considering that the age of onset of ADHD and SUDs are separated by at least a decade [13.14], this finding would support targeting of substance abuse prevention programs to girls with ADHD.Furthermore, results show that although the combined type of ADHDwas the predominant type in both genders, girls with ADHD were twice as likely as boys with ADHD to manifest the predominantly inattentive type of the disorder. Because symptoms of inattention are more covert than those of hyperactivity and impulsivity, their higher prevalence in girls with ADHDrelative to boys also may explain partially the markedly higher male-to-female ratios in referred versus nonreferred samples of children withADHD.This work also showed that the pattern of transmission of ADHD and comorbid disorders is not influenced by the proband's gender. This is true for the type of disorder transmitted and the degree of risk to relatives. The finding of no interactions between proband ADHD diagnosis and pro-band gender clearly rejects the idea that gender differences in comorbid disorders can be attributed to genes or other familial causes. Prior work had shown this to be true for the diagnosis of ADHD in relatives [15-20].Thus, gender and ADHD appear to be independent risk factors for comorbid psychopathology and for the familial transmission of comorbid psychopathology.In summary, these results suggest that gender was a limited effect modifier of ADHD as a risk factor for ADHD-associated dysfunction in referred children and adolescents. Gender, however, did impact the clinical presentation of the disorder. This was largely because girls with ADHDwere less likely than boys to have comorbid disruptive behavior problems and higher prevalence of symptoms of inattention. Because these features could result in gender-based referral bias unfavorable to girls, more work is needed in referred and nonreferred samples of youth with ADHD to more fully assess this issue. These results also showed similar patterns in the familial transmission of comorbid disorders in families of boys and girls with ADHD. Thus, although ADHD is associated with the familial trans-mission of comorbid disorders, the pattern of transmission is not influenced by the proband's gender. These similar patterns provide further evidence for the idea that, when ADHD is diagnosed in girls it corresponds to the same disorder diagnosed in boys.     

Absence of gender effects on attention deficit hyperactivity disorder: findings in nonreferred subjects

OBJECTIVE: In a previous study, the authors found that, compared with referred boys with attention deficit hyperactivity disorder (ADHD), girls are less likely to manifest comorbid disruptive behavior disorders and learning disabilities--characteristics that could adversely affect identification of ADHD in girls. However, because referral bias can affect outcome, these findings require replication in nonreferred groups of ADHD subjects. METHOD: The authors evaluated gender effects in a large group of nonreferred siblings (N=577) of probands with ADHD and non-ADHD comparison subjects. Ninety-eight of the nonreferred siblings (N=73 males, N=25 females) met the criteria for diagnosis of ADHD, and 479 (N=244 males, N=235 females) did not meet those criteria. All siblings were systematically and comprehensively assessed with measures of emotional, school, intellectual, interpersonal, and family functioning. The assessment battery used for the siblings was the same as that used for the probands. RESULTS: The nonreferred males and females with ADHD did not differ in DSM-IV subtypes of ADHD, psychiatric comorbidity, or treatment history. They also showed similar levels of cognitive, psychosocial, school, and family functioning. CONCLUSIONS: These findings suggest that the clinical correlates of ADHD are not influenced by gender and that gender differences reported in groups of subjects seen in clinical settings may be caused by referral biases.     

Social impairment in girls with ADHD: patterns, gender comparisons, and correlates

OBJECTIVE: To investigate social impairment in girls with attention-deficit/hyperactivity disorder (ADHD), compare the social functioning of boys and girls with ADHD, and explore the association between social dysfunction and conditions comorbid with ADHD. METHOD: Four groups of index children were studied: 267 children (127 girls) with ADHD and 234 non-ADHD comparison children (114 girls). Groups were compared on social functioning, psychopathology, and demographic characteristics. RESULTS: Girls with ADHD manifested significant deficits in interpersonal functioning compared with girls without ADHD and evidenced a similar degree of social impairment compared with boys with ADHD. ADHD and associated comorbid disorders were significant correlates of specific domains of social dysfunction in boys and girls with ADHD. CONCLUSIONS: Interpersonal deficits are a major correlate of ADHD, irrespective of gender, and appear to stem from the behaviors associated with ADHD as well as behaviors characteristic of conditions comorbid with ADHD.     

Clinical correlates of ADHD in females: findings from a large group of girls ascertained from pediatric and psychiatric referral sources.

OBJECTIVE: The scientific literature about attention-deficit hyperactivity disorder (ADHD) is based almost exclusively on male subjects, and girls with ADHD may be underidentified and undertreated. The aim of this study was to examine clinical correlates of ADHD in females using comprehensive assessments in multiple domains of functioning. METHOD: Subjects were 140 girls with ADHD and 122 comparison girls without ADHD ascertained from pediatric and psychiatric referral sources of the same age and social class. Subjects were assessed with structured diagnostic interviews, psychometric tests assessing intellectual functioning and academic achievement, as well as standardized assessments of interpersonal, school, and family functioning by raters who were blind to clinical diagnosis. RESULTS: Compared with female controls, girls with ADHD were more likely to have conduct, mood, and anxiety disorders; lower IQ and achievement scores; and more impairment on measures of social, school, and family functioning. CONCLUSIONS: These results extend to girls previous findings in boys indicating that ADHD is characterized by prototypical core symptoms of the disorder, high levels of comorbid psychopathology, and dysfunction in multiple domains. These results not only support findings documenting phenotypic similarities between the genders but also stress the severity of the disorder in females.     

A family study of psychiatric comorbidity in girls and boys with attention-deficit/hyperactivity disorder.

BACKGROUND: Because attention-deficit/hyperactivity disorder (ADHD) is relatively infrequent among girls, little is known about the nature and causes of psychiatric comorbidity in girls and the reason for gender differences in the prevalence of these comorbidities. METHODS: Using blinded, structured psychiatric interviews, we studied two groups of boys: 140 ADHD probands and 120 non-ADHD comparisons. These groups had 454 and 368 first-degree biological relatives, respectively. We also studied two groups of girls: 140 ADHD probands and 122 non-ADHD comparisons. These groups had 417 and 369 first-degree biological relatives, respectively. RESULTS: The co-occurrence of ADHD and comorbid psychopathology in families was the same for families ascertained through boy and girl probands. CONCLUSIONS: Our results suggest that boys and girls do not differ in the familial risk factors that mediate comorbid psychopathology and the familial aggregation of comorbid disorders in ADHD families. Although this is consistent with prior work suggesting more similarities than differences in the nature of psychiatric comorbidity in ADHD boys and girls, we cannot make strong conclusions, owing to the possibility of cohort effects.     

Symptom profiles in children with ADHD: effects of comorbidity and gender

OBJECTIVE: To examine ratings and objective measures of attention-deficit/hyperactivity disorder (ADHD) symptoms to assess whether ADHD children with and without comorbid conditions have equally high levels of core symptoms and whether symptom profiles differ as a function of comorbidity and gender. METHOD: Four hundred ninety-eight children from the NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder (MTA) were divided into comorbid groups based on the parent Diagnostic Interview Schedule for Children and assessed via parents' and teachers' Swanson, Nolan, and Pelham (SNAP) ratings and a continuous performance test (CPT). Comorbidity and gender effects were examined using analyses of covariance controlled for age and site. RESULTS: CPT inattention, impulsivity, and dyscontrol errors were high in all ADHD groups. Children with ADHD + oppositional defiant or conduct disorder were rated as more impulsive than inattentive, while children with ADHD + anxiety disorders (ANX) were relatively more inattentive than impulsive. Girls were less impaired than boys on most ratings and several CPT indices, particularly impulsivity, and girls with ADHD + ANX made fewer CPT impulsivity errors than girls with ADHD-only. CONCLUSIONS: Children with ADHD have high levels of core symptoms as measured by rating scales and CPT, irrespective of comorbidity. However, there are important differences in symptomatology as a function of comorbidity and gender.     

Gender differences among children with DSM-IV ADHD in Australia

OBJECTIVE: To examine gender differences among children meeting symptom criteria for DSM-IV attention-deficit/hyperactivity disorder (ADHD) identified in a nationally representative sample of Australian children. METHOD: From 2,404 children aged 6 to 13 years, 225 boys and 99 girls with ADHD symptoms were identified using the parent version of the Diagnostic Interview Schedule for Children and compared on parent reports of children's behavioral problems and impairment. RESULTS: When ADHD types were collapsed into a single group, boys and girls did not differ on core symptoms, comorbidity, and impairment with the exception that girls rated higher on somatic complaints and boys had poorer school functioning. However, gender patterns were found to vary across ADHD type on impairment measures of social problems, schoolwork difficulties, and self-esteem, with boys being generally rated as more impaired in the combined and hyperactive-impulsive groups but equally or less impaired in the inattentive group. CONCLUSIONS: The findings suggest the possibility of gender-specific risks associated with high levels of inattentive and hyperactive-impulsive symptoms indicating that ADHD subtype membership should be considered when conducting ADHD gender comparisons.     

Atypical frontal brain activation in ADHD: preschool and elementary school boys and girls

OBJECTIVE: To investigate patterns of frontal brain activation in unmedicated preschool and school boys and girls with attention-deficit/hyperactivity disorder (ADHD). METHOD: Baseline electroencephalographic activity of 117 children (66 aged 4 years, 51 aged 8 years) was subjected to power spectral analysis, and laterality scores were determined. RESULTS: Boys with ADHD exhibited a less right-lateralized frontal activation pattern than normal control boys. Girls with ADHD displayed a more right-lateralized frontal activation pattern than normal control girls. This finding applied to children at both 4 1/2 and 8 years of age. There was no difference between children with ADHD and children with ADHD plus oppositional defiant disorder. CONCLUSIONS: This pattern of frontal brain activation is in line with magnetic resonance imaging studies of ADHD. It could be demonstrated in children as young as 4 1/2 years, as well as in school-age children. The opposite direction of asymmetry in boys and girls stresses the importance of gender-specific analyses in ADHD.     

Adaptive, emotional, and family functioning of children with obsessive-compulsive disorder and comorbid attention deficit hyperactivity disorder

OBJECTIVE: The purpose of the study was to examine adaptive, emotional, and family functioning in a well-characterized group of children and adolescents with obsessive-compulsive disorder (OCD) and to evaluate the influence of comorbid attention deficit hyperactivity disorder (ADHD) on the levels of impairment in various functional domains. METHOD: The study group included 287 children and adolescents (191 boys, 96 girls) ages 7-18 years. Fifty-six subjects had a diagnosis of OCD only, 43 had both OCD and ADHD, 95 had ADHD, and 93 were unaffected comparison children. Best estimate DSM-IV diagnoses were assigned on the basis of structured interviews and clinical ratings. The children's functioning was evaluated with a comprehensive battery of well-established, standardized measures, including the Vineland Adaptive Behavior Scales, parents' ratings of social and family functioning, and children's self-reports of emotional adjustment. RESULTS: The children with OCD only were more impaired than were unaffected comparison subjects in most areas of adaptive functioning and emotional adjustment. Children with OCD plus ADHD had additional difficulties in social functioning, school problems, and self-reported depression. Impairment in daily living skills, reduced number of activities, and self-reported anxiety were uniquely associated with the diagnosis of OCD. Family dysfunction was associated with ADHD but not with OCD. CONCLUSIONS: Children and adolescents with OCD are impaired in multiple domains of adaptive and emotional functioning. When comorbid ADHD is present, there is an additional burden on social, school, and family functioning.     

Family study of girls with attention deficit hyperactivity disorder

OBJECTIVE: Because attention deficit hyperactivity disorder (ADHD) is relatively infrequent among girls, little is known about the causes of ADHD in girls. To help fill this gap in the literature, the authors assessed the familial transmission of ADHD in families ascertained through girls.METHOD: Interviewers who were blind to diagnosis administered structured psychiatric interviews to 140 girls with ADHD and their 417 first-degree relatives and to 122 girls without ADHD and their 369 first-degree relatives.RESULTS: The relatives of the ADHD girls had a significantly higher prevalence of ADHD, according to either the DSM-III-R or DSM-IV definition, than the relatives of the comparison girls. However, this did not differ from the prevalence the authors reported previously for families of boys with ADHD. Like the boys' families, the relatives of the girl probands also had significantly higher prevalences of antisocial, mood, anxiety, and substance use disorders, although the prevalence of familial antisocial disorders was lower than had been observed in the boys' families. There was no association between the DSM-IV subtypes of the probands and relatives.CONCLUSIONS: The familial transmission of ADHD and comorbid disorders generalizes to families of girls with ADHD. Neither proband gender nor subtype influences the familial transmission of ADHD.     

Association of comorbid anxiety with social functioning in school-age children with and without attention-deficit/hyperactivity disorder (ADHD)

Although attention-deficit/hyperactivity disorder (ADHD) is frequently comorbid with disruptive behavior disorders, less is known about ADHD and comorbid anxiety. To improve understanding about the association of anxiety and social functioning, we studied 223 6 to 9 year-old ethnically diverse boys and girls (M=7.4 years) with and without ADHD. According to parents, children with ADHD and anxiety (n=46) and ADHD only (n=71) were consistently less socially competent than comparison children (i.e., no anxiety and ADHD: n=80) and children with anxiety only (n=26), who did not differ from one another. A similar pattern emerged for teacher ratings where youth with ADHD only and ADHD with anxiety exhibited the most social problems, but they did not differ from each other. These data suggest that comorbid anxiety does not exacerbate social dysfunction among 6 to 9 year-old children with ADHD. We consider findings within a developmental psychopathology framework to further understand social development in children with ADHD and anxiety.     

Parental and family factors for attention-deficit hyperactivity disorder in Taiwanese children

OBJECTIVE: The present study aimed to examine the association between attention-deficit-hyperactivity disorder (ADHD) and maternal psychological distress, parenting style and perceived family support, and the child's interaction with parents and behavioural problems at home in Taiwan. METHODS: The sample included 375 medicated pediatric patients with DSM-IV ADHD, and 750 school controls selected based on the age and gender structures of the ADHD group. Mothers reported on the Chinese Health Questionnaire, the Chinese versions of the Parental Bonding Instrument, the Family Adaptation, Partnership, Growth, Affection, and Resolve, and the Home Behaviours of the Social Adjustment Inventory for Children and Adolescents. RESULTS: Mothers of children with ADHD reported greater psychological distress and perceived less support from their families than did mothers of controls. Moreover, mothers of children with ADHD were less affectionate and more overprotective and controlling toward their children than were mothers of controls. This difference was more apparent in boys than in girls. Children with ADHD were less likely to interact with their parents, yet demonstrated more severe behavioural problems at home. CONCLUSIONS: Although the Taiwanese children with ADHD were under treatment with methylphenidate, they and their families still encountered a variety of difficulties in interaction, support, and communication with each other. Therefore, the parental approach should be integrated into the medication treatment for ADHD in Taiwan.     

Response to emotional stimuli in boys with conduct disorder

OBJECTIVE: Boys with conduct disorder are at risk of persistently showing antisocial behavior in adult life, particularly if they have an additional diagnosis of attention deficit hyperactivity disorder (ADHD). In the search for biological risk factors that predispose children to the development of antisocial personality disorder, research has provided substantial data suggesting that autonomic hyporesponsiveness indicates a greater likelihood of future antisocial behavior. The purpose of this study was to examine autonomic arousal in boys with conduct disorder, comorbid conduct disorder and ADHD, and ADHD only. METHOD: In addition to self-ratings, electrodermal responses to pleasant, neutral, and unpleasant slides were obtained for 21 boys with conduct disorder and 54 boys with ADHD plus conduct disorder. Forty-three boys with a diagnosis of ADHD only were recruited as a clinical comparison group, and 43 boys with no conduct disorder or ADHD were included as a healthy comparison group. All subjects were ages 8-13 years. RESULTS: Compared to the healthy subjects and the subjects with ADHD only, the boys with conduct disorder and with ADHD plus conduct disorder reported lower levels of emotional response to aversive stimuli and lower autonomic responses to all slides independent of valence. CONCLUSIONS: Although the self-report data supported a deficit in reactivity to explicit fear cues, the psychophysiological data indicated that boys with conduct disorder both with and without a comorbid condition of ADHD are characterized by a generalized deficit in autonomic responsivity in an experimental situation in which children were exposed to complex visual stimuli of unpredictable affective quality. Psychophysiological findings may point to a deficit in associative information processing systems that normally produce adaptive cognitive-emotional reactions.     

Psychopathology in females with attention-deficit/hyperactivity disorder: a controlled, five-year prospective study.

BACKGROUND: Despite the importance of understanding the long-term outcome of children with attention-deficit/hyperactivity disorder (ADHD), the available literature is predominantly based on male samples. This study estimated the lifetime burden of comorbid psychopathology in a large sample of girls with and without ADHD followed up over five years. METHODS: We conducted a blind, five-year prospective longitudinal study of girls with (n=140) and without (n=122) ADHD, aged 6-18 years at baseline, consecutively ascertained from either community pediatricians or psychiatrists at an academic medical center. At the five-year follow-up, 123 (88%) and 112 (92%) of the ADHD and control children, respectively, were re-assessed at a mean age of 16.7 years. Psychiatric disorders were assessed using blinded structured diagnostic interviews. RESULTS: At follow-up, females with ADHD were at significantly higher risk than controls to manifest disruptive behavior, mood and anxiety disorders, and substance dependence. The magnitude of increased risk was greatest for major depression and oppositional-defiant disorder, followed by substance dependence and anxiety disorders. CONCLUSIONS: These prospective follow-up findings documenting high morbidity associated with ADHD extend to females previously reported findings in male samples and underscore the importance of early recognition and intervention efforts for youth with ADHD of both genders.     

Gender differences in a clinic-referred sample of Taiwanese attention-deficit/hyperactivity disorder children

The purpose of this study was to examine gender differences within a clinic-referred sample of 6-11-year-old Taiwanese children with attention-deficit/hyperactivity disorder (ADHD)- combined subtype. The subjects were 21 girls with a diagnosis of ADHD from the 4th edition of the Diagnostic and Statistical Manual and 21 age-matched boys with ADHD. Comparisons were made of behavioral ratings, cognitive profiles, and vigilance/attention assessments between these two groups. The results found ADHD girls and ADHD boys to be statistically indistinguishable on nearly all measures except the subtests of block design (P = 0.016), the discrepancy between Performance Intelligence Quotient and Verbal Intelligence Quotient (P = 0.019), and the discrepancy between fluid and crystallized IQ (P = 0.041). In the study samples, ADHD girls and ADHD boys were strikingly similar on a wide range of measures. ADHD boys and girls in clinics may be expected to show more similarities than differences in treatment needs. However, these results should be interpreted with caution since data were only from clinic-referred samples.     

Gender differences in ADHD: implications for psychosocial treatments

Attention-deficit/hyperactivity disorder (ADHD) has now been recognized to exist in both males and females, albeit the literature supports a higher prevalence in males. However, when girls are diagnosed with ADHD, they are more often diagnosed as predominantly inattentive than boys with ADHD. This paper provides a review of gender differences noted across the lifespan in terms of psychosocial functioning, cognitive abilities and psychiatric comorbidities. Males and females with ADHD are more similar than different, and generally symptoms of ADHD are not sex specific. Small gender differences have been found: adolescent girls with ADHD have lower self-efficacy and poorer coping strategies than adolescent boys with ADHD, but these differences tend to disappear by adulthood; rates of depression and anxiety may be higher (especially in adolescence) while physical aggression and other externalizing behaviors may be lower in girls and women with ADHD, although not all studies support these findings (e.g., non-referred samples show similar rates of coexisting psychiatric disorders between boys and girls with ADHD). However, many studies suffer from small sample sizes, referral biases, differences in diagnostic procedures and possible rater influences. Psychosocial treatments are reviewed and discussed with reference to the reported gender differences in functioning as well as the global deficits noted in all samples. Although the data available so far suggest that psychosocial treatments are likely to be equally effective in males and females, this conclusion is based more on the small number of gender differences noted in overall functioning and less on empirical research on treatment by sex effects and the moderating role of sex, an effect only investigated by the Multi-modal Treatment Study of ADHD group, to date. Future research should include equal representation of both sexes in samples such that treatment analyses by gender can be routinely conducted.     

Effect of anxiety on cognition, behavior, and stimulant response in ADHD

The effect of the comorbidity of overanxious disorder (ANX) in attention deficit hyperactivity disorder (ADHD) on laboratory measures of behavior, cognition, and stimulant response was examined. Seventy-nine children who met DSM-III-R criteria for ADHD were tested further for an oppositional defiant disorder (ODD), conduct disorder (CD), or ANX. Subjects with comorbid ANX showed less impulsiveness on a laboratory measure of behavior and had longer, sluggish reaction times on the Memory Scanning Test than those without ANX. ADHD subjects with comorbid ANX were less frequently diagnosed as CD. Forty-three of the subjects completed a double-blind trial of methylphenidate; subjects with comorbid anxiety had a significantly poorer response to the stimulant than those without anxiety, while the comorbidity of ODD or CD did not affect stimulant response. The results suggest that ADHD with comorbid ANX may represent children with primary anxiety who develop secondary inattentiveness, or they may represent a different subtype of ADHD, perhaps similar to the condition of attention deficit disorder without hyperactivity under DSM-III.     

Altered performance on an ocular fixation task in attention-deficit/hyperactivity disorder.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a common psychiatric disorder without validated objective markers. Eye movement studies may be useful in providing objective criteria for characterizing the disorder. METHODS: We compared 53 children (29 girls) with ADHD to 44 healthy control children (18 girls) on a 21-sec fixation task. Large saccades (> 4 degrees ) away from the fixation point were analyzed. RESULTS: Children with ADHD made more large saccades that interrupted fixation than did control children (p =.001). Mean scores of the ADHD group did not change significantly with subsequent retesting on placebo (p =.11); however, there was poor intrasubject correlation (r =.16). CONCLUSIONS: Both boys and girls with ADHD made significantly more intrusive saccades during fixation than did control subjects, possibly reflecting intrinsic neurologic dysfunction; however, a probable "floor effect" obviates conclusions about the reliability of this measure.     

Psychiatric comorbidity in adult attention deficit hyperactivity disorder: findings from multiplex families

OBJECTIVE: Patterns of psychiatric comorbidity were assessed in adults with and without attention deficit hyperactivity disorder (ADHD) identified through a genetic study of families containing multiple children with ADHD. METHOD: Lifetime ADHD and comorbid psychopathology were assessed in 435 parents of children with ADHD. Rates and mean ages at onset of comorbid psychopathology were compared in parents with lifetime ADHD, parents with persistent ADHD, and those without ADHD. Age-adjusted rates of comorbidity were compared with Kaplan-Meier survival curves. Logistic regression was used to assess additional risk factors for conditions more frequent in ADHD subjects. RESULTS: The parents with ADHD were significantly more likely to be unskilled workers and less likely to have a college degree. ADHD subjects had more lifetime psychopathology; 87% had at least one and 56% had at least two other psychiatric disorders, compared with 64% and 27%, respectively, in non-ADHD subjects. ADHD was associated with greater disruptive behavior, substance use, and mood and anxiety disorders and with earlier onset of major depression, dysthymia, oppositional defiant disorder, and conduct disorder. Group differences based on Kaplan-Meier age-corrected risks were consistent with those for raw frequency distributions. Male sex added risk for disruptive behavior disorders. Female sex and oppositional defiant disorder contributed to risk for depression and anxiety. ADHD was not a significant risk factor for substance use disorders when male sex, disruptive behavior disorders, and socioeconomic status were controlled. CONCLUSIONS: Adult ADHD is associated with significant lifetime psychiatric comorbidity that is not explained by clinical referral bias.     

Impact of behavioral/developmental disorders comorbid with conduct disorder

Aims: The aim of the present study was to verify the comorbidity of conduct disorder (CD) and behavioral/developmental disorders in children and adolescents, and to examine the traits of CD comorbid with them. Methods: Subjects were 64 children (60 boys, four girls) who were resident at three institutions for delinquent children or who were conduct‐disordered outpatients of a university hospital aged under 18 years. A diagnostic interview was carried out by experienced child psychiatrists and the intelligence score and the Adverse Childhood Experiences score were measured by a licensed psychologist. Results: A total of 57 children were diagnosed as having CD, of whom 26 (45.6%) were diagnosed with comorbid attention‐deficit–hyperactivity disorder (ADHD), 12 were diagnosed with comorbid pervasive developmental disorder (PDD, 21,1%), and 19 (33.3%) had no comorbidity of either disorder. Six children (18.8% of CD comorbid with ADHD) met the criteria for both ADHD and PDD. The group with comorbid PDD was significantly younger at onset (F = 6.51, P = 0.003) and included unsocialized type more frequently (χ² = 6.66, P = 0.036) compared with the other two groups. Conclusions: Clinicians should be aware that not only ADHD but also PDD may be comorbid with CD. Establishment of the correct diagnosis is important because recognizing the presence of PDD will enable us to provide appropriate treatment and guidance, which may improve prognosis.