Predictors of Nonresponse to Psychosocial Treatment in Children and Adolescents with Disruptive Behavior Disorders

Abstract

Objective:

A crucial issue in youths with disruptive behavior disorders, including oppositional defiant disorder and conduct disorder, is the refractoriness to treatments. A multimodal approach with individual therapy to improve social skills and self-control and family and school interventions is the best psychosocial treatment. Predictors of poor response to psychosocial treatment remain understudied. We aimed at exploring whether callous (lack of empathy and guilt) and unemotional (shallow emotions) (CU) trait and type of aggression (predatory vs. affective) can affect response to psychosocial treatment in referred youths with disruptive behavior disorders.

Methods:

The sample consisted of 38 youths (28 boys and 10 girls, age range: 6–14 years, mean age: 13.1 ± 2.6 years) diagnosed as having oppositional defiant disorder or conduct disorder according to Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) criteria and a clinical interview (Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children—Present and Lifetime Version), who completed a 6-month therapeutic program at our hospital. Patients were assessed according to severity and improvement (Clinical Global Impressions—Severity score [CGI-S] and CGI—Improvement score), functional impairment (Children's Global Assessment Scale [C-GAS]), type of aggression, predatory versus affective (Aggression Questionnaire), and CU dimension (Antisocial Process Screening Device and the Inventory of CU Traits).

Results:

Among the 38 patients, 21 (55.3%) were responders and 17 (44.7%) were nonresponders, according to CGI—Improvement score and CGI-S. Nonresponders were more impaired at the baseline according to CGI-S and C-GAS. Nonresponders presented higher scores of predatory aggression, whereas affective aggression did not differ between groups. Nonresponders presented higher scores in CU trait of Antisocial Process Screening Device and in Inventory of CU total score (callous trait), but these differences did not survive Bonferroni correction.

Conclusions:

Severity at the baseline and predatory aggression are negative predictors of psychosocial treatment, but the role of the callous trait needs more exploration in larger samples. Further research may increase our diagnostic and prognostic capacities, thus improving our treatment strategies.

Introduction

O ne of the crucial issues in prognosis of children and adolescents with disruptive behavior disorders (DBDs), including conduct disorder (CD) and oppositional defiant disorder, is the high resistance to treatments. No single intervention is effective against severe DBDs (AACAP 1997, 2007; Burke et al. 2002). Although psychosocial, psychotherapeutic, and familial approaches are usually first-line treatment options (Pappadopulos 2003), severe behavior disorders are frequently refractory to such approaches (Malone et al. 1997; Kazdin 2000). A multimodal approach including individual sessions to improve social skills and self-control strategies and family and school interventions within a comprehensive program is considered the best psychosocial intervention to meet the complex needs of these patients. Especially when aggression is the main symptom, and/or when comorbidity is heavier, medications can improve some maladaptive behaviors and increase the person's ability to benefit from nonpharmacologic interventions (Masi et al. 2006, 2009; Ipser and Stein 2007).

A major goal in clinical research on DBDs is to find out possible predictors of negative social outcome of DBDs, according to specific clinical, personality, and temperamental variables on the one side and context variables on the other. These factors may allow for further subtyping the broad category of DBD into more specific and homogeneous groups, which may more clearly define prognostic and therapeutic implications and thus improve our interventions.

According to our previous study, nonresponders to treatments (both pharmacologic and psychosocial) were more severe at the baseline, presented more severe verbal and physical aggression, a greater rate of predatory subtype of aggression, and a higher rate of substance abuse, and received psychosocial interventions less frequently (Masi et al. 2008). Predictors of psychosocial intervention may be different from predictors of a pharmacological intervention, because different mechanisms are involved, such as sensitivity to fear and distress and to positive and negative reinforces, sense of empathy and guilt, and type of emotionality (Masi et al. 2008).

Different dimensions of aberrant behavior can be described in children and adolescents with DBDs, the definition of which may have clinical and prognostic implications. Two main modalities of aggression, impulsive or controlled, have been described (Vitiello and Stoff 1997). Impulsive aggression is characterized by overt outbursts of inappropriate, unplanned, and unprofitable maladaptive behaviors, usually after little provocation and with a poorly controlled affective activation. Controlled aggression is characterized by covert, planned, goal-oriented, profitable behaviors and low autonomic activation. This subtyping has been hypothesized to have implications on treatment response, supporting the notion that it may identify two variants of CD, with overt or covert behaviors, in terms of clinical expression and familial aggregation (Malone et al. 1988; Monuteaux et al. 2004; Masi et al. 2006).

Evidence from the literature suggests that the concept of psychopathy, borrowed by adult psychiatry, may be a meaningful construct even in youths. Psychopathy not only designates a particularly severe and violent group of patients with antisocial behavior, but also it implies possible processes and pathways leading to an increased risk for severe antisocial behavior (Cleckley 1976). The concept of “psychopathy” in adults with behavioral disorders is associated with more severe and stable conduct problems, delinquency and aggression, and more frequent treatment-refractoriness (Frick and Dickens 2006). A major dimensional component of the concept of “psychopathy,” along with narcissism and impulsivity, is an affective factor including callous (lack of empathy and guilt) and unemotional (shallow emotions) traits (Cooke et al. 2006). Callous unemotional (CU) dimension results have been shown to be the most specific trait in disentangling a specific category of antisocial individuals, both in adults (Cooke and Michie 1997) and in adolescents (Caputo et al. 1999) and preadolescents (Christian et al. 1997). Deficits in emotional arousal to fear and distress, as well as low sensitivity to punishment and low impact of the negative consequences of actions, not only increase the risk of antisocial behavior, but also sensitivity to treatment. This knowledge may help clinicians in focusing their intervention in a more specific way. According to the proposed 5th edition of Diagnostic and Statistical Manual of Mental Disorders, revision of the diagnostic criteria for mental disorders in childhood and adolescents, symptoms related to CU dimension will be included in the diagnostic features of DBDs, to further specify clinically meaningful subtypes (Moffitt et al. 2008).

The aim of this study was to explore whether type of aggression and psychopathic traits (namely CU traits) may affect the response to a psychosocial treatment.

Methods and Materials

Sample

The sample included 38 referred children and adolescents (28 boys [73.7%] and 10 girls [26.3%], age range: 6–16 years, mean age: 13.1 ± 2.6 years). Patients with mental retardation, pervasive developmental disorders, or psychotic disorders were not included in the sample. Patients were diagnosed according to a diagnostic interview, the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children—Present and Lifetime Version (K-SADS-PL) (Kaufman et al. 1997), administered to patients and parents by child psychiatrists specifically trained in the use of this interview. Diagnoses were considered positive when Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) (American Psychiatric Association 1994) diagnostic criteria were met, including number of symptoms, duration, and degree of impairment (Clinical Global Impressions—Severity score [CGI-S]) (Guy 1976) 4 or above, and Children's Global Assessment Scale score (C-GAS) (Shaffer et al. 1983) 60 or less. These patients have not been included in previous studies from our group. All patients and their families participated voluntarily in the study after written informed consent was obtained for assessment and treatment procedures. The study was approved by the ethical committee of our hospital.

Method

All patients received systematic evaluation, using historical information, prolonged observations of interactions with peers, parents, and/or examiners, and a structured assessment:

K-SADS (administered individually to the adolescents and to their parents) is an interview according to DSM-IV, which explores the presence or absence of each of the symptoms in different psychiatric syndromes. Trained child psychiatrists with specific experience in adolescent psychiatric disorders administered the clinical interview. To improve the reliability and validity of the diagnoses, after each interview, clinical data from each subject–parent pair were reviewed by the research clinicians for the purpose of consensus.

CGI-S (Guy 1976) is a single item, recorded at the baseline, which rates the severity of global symptomatology on a scale from 1 (Normal) to 7 (Extremely Ill). CGI—Improvement score (Guy 1976) is a single item, recorded during the follow-up, which rates behavior from 1 (Very Much Improved) to 7 (Very Much Worsened).

C-GAS (Shaffer et al. 1983) describes the severity of functional impairment on a scale from 0 (Severe Impairment) to 100 (Superior Functioning). It was designed for use with children from 4 to 16 years of age. Scores above 70 indicate normal functioning.

Child Behavior Checklist (Achenbach 1983) is a 118-item standardized format, completed by parents for recording behavioral problems and competencies in children 4–16 years of age. One hundred eighteen behavior problem items are aggregated in eight different subscales (withdrawn, somatic complaints, anxiety/depression, social problems, thought problems, attention, delinquent behavior, aggressive behavior) related to both internalizing and externalizing domains. Each item is scored on a three-step response scale.

Aggression Questionnaire (Vitiello et al. 1990) is an instrument completed by the clinician to classify aggression in children and adolescents into “predatory” (controlled and planned), “affective” (impulsive and explosive), and “mixed” subtypes. The Aggression Questionnaire is a 10-item scale that includes statements about aggression presented in random order: 5 of the items assess for predatory aggression, and 5 for affective aggression. Each item is scored as 0 when it is not present, or 1 when it is present. In our study, a mixed aggression was also considered when the patients scored between −1 and +1, indicating a balance between predatory and affective components. The predatory/affective index is obtained by subtracting the affective score from the predatory score.

Antisocial Process Screening Device (APSD) (Frick and Hare 2001), APSD Youth version (APSD-Y), and APSD Parent version: APSD assesses the same traits explored by the Psychopathy Checklist—Revised (Hare 1991) and is the most frequently used measure for the assessment of psychopathic traits in adults in jail. The APSD is a structured clinical interview with 20 items. Factorial analysis using a nonclinical sample of 1,136 children and adolescents found three main dimensions: CU (six items), narcissistic (seven items), and impulsivity (five items).

Inventory of Callous-Unemotional Traits (ICU) (Frick 2003), ICU Youth (ICU-Y) version, and ICU Parents (ICU-P) version: The ICU is a rating scale with 24 items exploring the CU dimension, with 3 scores, 0 (never), 1 (sometimes), and 2 (often) (in our study, we did not use the ICU-Teachers). The ICU was first tested in a large nonclinical sample of 1,443 German adolescents, using the self-report version (Essau et al. 2006). The factorial analysis showed three main dimensions: callous (11 items), indifference (8 items), and unemotionality (5 items). Only one other study used this measure (self-report version) in young adults in jail (Kimonis et al. 2008).

Treatment

All patients were treated in our hospital with psychosocial interventions for at least 6 months. Psychosocial approach consisted of multimodal interventions, inspired from the multi-systemic treatment (Henggeler et al. 1998), including cognitive behavior programs for groups of 4–6 peers. The duration of the program was 6 months, with weekly sessions and a second cycle for patients who did not respond to the first program. The program was based on structured exercises and group discussions aimed at improving insight about emotions of self and others, management of rage and temper outbursts, and inner dialog; role playing to explore alternatives to behavioral crises; videos with group discussion; dramatization; and problem solving. Weekly individual psychotherapeutic sessions and weekly counseling for parents were included (Henggeler et al. 1998).

The patients were considered responders when they presented a CGI–I score 1 (very much improved) or 2 (much improved) and a CGI-S score ≤4 in three consecutive sessions.

Statistical analyses

Patients were compared using an unpaired t-test on continuous variables. Considering the large number of comparisons performed and the number of subjects in each group, our results are prone to both type I and type II errors. For this reason, a Bonferroni correction was applied, setting alpha = 0.003.

Results

Among the 38 patients who completed their therapeutic program, 21 (55.3%) were responders and 17 (44.7%) nonresponders (Table 1). The two groups were compared according to selected variables. Gender, age, and age at onset did not differ between the groups. Nonresponders were more impaired at the baseline according to clinical severity (CGI-S, 4.7 ± 0.8 vs. 3.8 ± 0.7, p = 0.000) and functional impairment (C-GAS, 37.7 ± 4.6 vs. 45.4 ± 5.2, p = 0.000).

Table 1.

Comparison Between Responders and Nonresponders to Psychosocial Treatment

	Nonresponders	Responders	t/χ ²	df	OR (95% CI)	p Value
	N = 17(44.7%)	N = 21(55.3%)
Males, n (%)	14 (82.3)	14 (66.7)	0.5	2		0.471
Age, years, mean (SD)	13.7 (2.7)	12.6 (2.6)	1.3	36	−0.7–2.8	0.221
CGI-Severity (baseline), mean (SD)	4.7 (0.8)	3.8 (0.7)	3.7	36	0.4–1.4	0.000^a
CGI-Severity (endpoint), mean (SD)	4.1 (0.5)	3.0 (0.3)	8.4	36	0.8–1.4	0.000^a
CGI-Improvement, mean (SD)	3.4 (0.8)	1.8 (0.4)	8.0	36	1.2–2.0	0.000^a
C-GAS (baseline), mean (SD)	37.7 (4.6)	45.4 (5.2)	−4.8	36	−11.0 to −4.4	0.000^a
Impulsive aggression	3.4 (1.8)	2.8 (1.8)	1.0	36	−0.6–1.8	0.314
Predatory aggression	2.4 (1.6)	0.8 (1.0)	3.8	36	0.7–2.5	0.000^a
APSD (Y-V), total	16.1 (4.0)	13.0 (5.6)	1.9	36	−0.2–6.4	0.063
Callous unemotional (Y-V)	4.9 (2.0)	3.6 (1.6)	2.2	36	0.1–2.5	0.033^b
Narcissism (Y-V)	5.1 (1.4)	4.0 (2.6)	1.6	36	−0.3–2.5	0.126
Impulsivity (Y-V)	4.2 (1.9)	4.6 (2.0)	−0.6	36	−1.7–0.9	0.535
ICU (Y-V)	30.0 (9.9)	23.9 (7.1)	2.2	36	0.5–11.7	0.034^b
Callosity (Y-V)	11.8 (5.4)	9.1 (4.0)	1.8	36	−0.4–5.8	0.085
Indifference (Y-V)	11.2 (5.5)	9.2 (4.5)	1.2	36	−0.13–5.3	0.225
Unemotionality (Y-V)	6.8 (3.3)	5.5 (2.8)	1.3	36	−0.7–3.3	0.197
APSD (P-V), total	19.2 (5.8)	18.9 (5.5)	0.2	36	−3.4–4.0	0.871
Callous unemotional (P-V)	6.0 (2.1)	6.2 (1.9)	−0.3	36	−1.5–1.1	0.760
Narcississm (P-V)	6.5 (3.1)	6.1 (2.7)	0.4	36	−1.5–2.3	0.673
Impulsivity (P-V)	5.4 (1.4)	5.6 (1.5)	−0.4	36	−1.1–0.8	0.676
ICU (P-V), total	34.5 (8.00)	32.7 (9.4)	0.6	36	−4.0–7.6	0.535
Callosity (P-V)	12.5 (4.2)	12.8 (5.2)	−0.2	36	−3.5–2.9	0.849
Indifference (P-V)	15.5 (3.1)	14.1 (4.0)	1.2	36	−1.0–3.8	0.245
Unemotionality (P-V)	6.6 (2.8)	6.8 (3.8)	−0.2	36	−2.4–2.0	0.858
CBCL total	70.3 (6.1)	69.8 (8.8)	0.2	36	−4.6–5.6	0.844
CBCL Internalizing Score	66.1 (9.2)	67.9 (10.3)	−0.6	36	−8.3–4.7	0.578
CBCL Externalizing Score	69.5 (7.8)	68.2 (9.0)	0.5	36	−4.3–6.9	0.642
Withdrawal/depression	64.6 (8.3)	68.5 (10.7)	−1.2	36	−10.3–2.5	0.226
Somatization	62.1 (8.7)	68.1 (12.7)	−1.7	36	−13.3–1.3	0.106
Anxiety	65.4 (11.1)	65.4 (10.6)	0.0	36	−7.1–7.1	1.000
Socialization	68.0 (8.5)	67.8 (9.1)	0.1	36	−5.6–6.0	0.945
Thought disorder	61.9 (9.9)	64.0 (8.7)	−0.7	36	−8.2–4.0	0.491
Attention	73.1 (8.8)	68.0 (5.6)	2.2	36	0.3–9.9	0.037^b
Delinquency	66.1 (7.3)	64.9 (6.2)	0.5	36	−3.2–5.6	0.587
Aggressiveness	71.41 (10.85)	71.47 (8.51)	−0.1	36	−6.4–6.2	0.975

p < 0.003 (Bonferroni correction).

p < 0.05.

df = degrees of freedom; OR = odds ratio; CI = confidence interval; SD = standard deviation; CGI = Clinical Global Impressions; C-GAS = Children Global Assessment Scale score; APSD = Antisocial Process Screening Device; ICU = Inventory of Callous/Unemotional Traits; Y-V = Youth Version; P-V = Parent Version; CBCL: Child Behavior Checklist for ages 6 to 18 years.

Nonresponders presented higher scores of predatory aggression (2.35 ± 1.62 vs. 0.86 ± 1.01, p = 0.001), whereas affective aggression did not differ between groups.

A difference between groups was found in the CU traits, according to ICU total score—Youth version (30 ± 9.9 vs. 23.9 ± 7.1, p = 0.034) and the CU trait of APSD-Y version (4.9 ± 2.0 vs. 3.6 ± 1.6, p = 0.033), but this difference did not survive Bonferroni correction. These differences were nonsignificant when the parent version of the questionnaires were considered.

It is noteworthy that another parent-rated instrument, the Child Behavior Checklist—Parent version, did not differentiate the two groups, except for “attention” (p = 0.037).

Discussion

Predictors of good or poor response in psychosocial treatments of children and adolescents with DBDs remain poorly understood. Personality features may affect response to behavioral programs, as they affect the patients' sensitivity to positive and negative reinforces. The aim of this study was to explore possible factors, including type of aggression (predatory vs. impulsive) and psychopathic and CU traits, associated with treatment refractoriness in a small sample of children and adolescents who completed a psychosocial treatment program. In our sample, severity at the baseline in terms of both clinical severity and functional impairment was strongly associated with poorer response.

Patients who improved less more frequently presented a predatory aggressiveness. This feature may be a critical psychopathological factor affecting the response to treatments. This is consistent with other findings from the literature (Vitiello and Stoff 1997; Masi et al. 2006), which indicates that the lowest impulsive component of aggressive behaviors is associated with the poorest response to treatments. This issue, consistent with our previous studies on predictors of pharmacologic treatment, may be a discriminant factor in differentiating various forms of CD, with overt or covert aggression (Masi et al. 2008, 2009).

Psychopathic trait was also associated with treatment nonresponse, both assessed with ICY-Y and the callous dimension of the APSD-Y, but according to the Bonferroni correction it can be considered only a trend, which involved the CU, but not the narcissistic and impulsive components of APSD-Y or the indifference and unemotionality components of ICU-Y. These findings suggest that the callous trait may be a possible predictor of poor response to psychosocial interventions. It may be hypothesized that the psychopathic trait, and specially the CU dimension, may be more labile in youths, and its predictive value lower compared with adults, and detectable only with larger samples. Further exploration of developmental aspects of CU dimension, as well as their interactions with other pertinent dimensions, within a biopsychosocial perspective, may help to define significant predictors of outcome, including the response to treatments (Cohen 2010).

Another relevant issue is that the callous trait was related to treatment nonresponse according to the youth version of the questionnaires, whereas the parent version of the questionnaires was unable to detect this trait in nonresponders. This finding suggests that parents may be more able to detect overt behavioral disorders, whereas the more subtle callous, narcissistic, and non-affective dimensions are more difficult to uncover. An alternative explanation may be that some youths may overestimate their callous trait, making this variable less robust to prediction.

The relationship between predatory aggressiveness and CU trait remains an unexplored field of research, even though it may have strong implications in terms of intervention strategy. It may be questioned if the two dimensions are related or if they represent independent specifiers, which may lead to a specific subtyping of behavior disorders, or if subjects with both psychopathic trait and predatory aggression are a more severe and treatment-refractory population. The issue is not merely nosological, as both these features can be detected early and they may lead to more timely and intensive treatment programs for preventing the development of an antisocial personality disorder.

Our study presents several methodological limitations. A possible limitation may be a referral bias, because patients admitted to our third-level research hospital may represent a subgroup of more severely impaired subjects. This selection bias may limit the generalization of the conclusions of this study to epidemiological samples.

Further research including larger samples of patients are warranted to support this conclusion. However, our study may be relevant because it has delineated possible risk factors contributing to poor treatment outcome. We describe an unselected sample of children and adolescents with DBDs treated in an ordinary clinical setting. Long-term naturalistic prospective studies might represent an important source of information regarding the effectiveness of a treatment over extended periods of time under ordinary clinical conditions.

Footnotes

Financial Disclosure

Dr. Masi is a consultant for Eli Lilly, Shire, and Novartis, have received research grants from Eli Lilly, and has been a speaker for Eli Lilly, GlaxoSmithKline, Sanofi-Aventis, Janssen Cilag, and Astra-Zeneca. Drs. Manfredi, Milone, Muratori, Polidori, Ruglioni, and Muratori do not have disclosures to declare.

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