Autonomic nervous system markers of psychopathology in childhood-onset schizophrenia.

BACKGROUND: Consistent abnormalities in peripheral indicators of autonomic activity, ie, skin conductance (SC) and heart rate (HR), have been reported in adult-onset schizophrenia. Herein, we use these markers to test the hypothesis of continuity between childhood-onset schizophrenia and adult-onset schizophrenia. METHODS: Skin conductance and HR were recorded from 21 severely ill children and adolescents (mean age, 14.1 years) with childhood-onset (< or = 12 years) schizophrenia (patient group) and from 54 age-matched controls (control group) during a rest period, a series of innocuous tones, reaction time instructions, and a simple warned reaction time task. RESULTS: During rest, patients had higher rates of spontaneous SC responses (SCRs) and HRs than controls, but their SC level was marginally lower and declined more slowly over time. Half of the patients, compared with 4% of the controls, failed to give SC-orienting responses to the first 2 tones. Patients who responded had impaired SCR magnitudes, and their habituation was more erratic than that of controls. The increase in SC level and SCR frequency at the onset of the task period was greatly attenuated in the patients, so that both variables were higher in controls. Patients had smaller SCRs and anticipatory HR responses to the reaction time stimuli. Skin conductance nonresponding was associated with negative and total symptoms, and spontaneous SCR frequency was associated with positive symptoms. CONCLUSIONS: The findings show similar abnormalities in autonomic nervous system activity in childhood-onset schizophrenia to those found in adult chronic schizophrenia, thus supporting the hypothesis of continuity of the childhood and adult forms of the illness. Comparisons with data from other childhood disorders suggest that the combination of low-elicited SC activity with high levels of spontaneous SC activity may be specific to schizophrenia.

Childhood-onset schizophrenia. A double-blind clozapine-haloperidol comparison.

BACKGROUND: Childhood-onset schizophrenia is a rare but severe form of the disorder that is often treatment-refractory. In this study, the efficacy and adverse effects of clozapine and haloperidol were compared for children and adolescents with early-onset schizophrenia. METHODS: Twenty-one patients (mean [+/-SD] age, 14.0 +/- 2.3 years) with onset of Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition-defined schizophrenia that began by age 12 years and who had been nonresponsive to typical neuroleptics participated in the study. Patients were randomized to a 6-week double-blind parallel comparison of clozapine (mean [+/-SD] final dose, 176 +/- 149 mg/d), or haloperidol, (16 +/- 8 mg/d). RESULTS: Clozapine was superior to haloperidol on all measures of psychosis (P = .04-.002). Positive and negative symptoms of schizophrenia improved. However, neutropenia and seizures were major concerns. To date, one third of the group has discontinued using clozapine. CONCLUSIONS: Clozapine has striking superiority for positive and negative symptoms in treatment-refractory childhood-onset schizophrenia. However, due to possibly increased toxic effects in this pediatric population, close monitoring for adverse events is essential.

Brain anatomic magnetic resonance imaging in childhood-onset schizophrenia.

BACKGROUND: Early-onset schizophrenia (first psychotic symptoms by age 12 years) has been the subject of a small number of studies, and its biological continuity with later-onset disorder has not been established. In this study quantitative anatomic brain magnetic resonance images of children and adolescents with early-onset schizophrenia were compared with those of matched controls. Brain abnormalities in childhood-onset schizophrenia were examined in relation to those reported for later-onset schizophrenics. METHODS: Anatomic brain magnetic resonance imaging scans were obtained for 21 patients (mean +/- SD age, 14.6 +/- 2.1 years; range, 10 to 18 years) with childhood-onset schizophrenia (13 males, eight females) and 33 age-, sex-, height-, and weight-matched normal controls. Quantitative measurements were obtained for the cerebrum, anterior frontal region, lateral ventricles, thalamus, caudate, putamen, and globus pallidus. RESULTS: Total cerebral volume and midsagittal thalamic area were smaller in the patients (analysis of variance, P = .002, and analysis of covariance, P = .03, respectively); the caudate, putamen, and globus pallidus were larger in the patients (analysis of covariance, P = .05, P = .007, and P < .001, respectively); and the lateral ventricles tended to be larger in the patients (analysis of covariance, P = .06). Globus pallidus enlargement correlated with neuroleptic exposure and with age of onset of psychosis. The magnitude of abnormalities compared with controls was similar to that reported in adult studies, although there was a trend toward relatively smaller cerebral volumes for the childhood-onset group compared with controls. CONCLUSION: Brain anatomic abnormalities in childhood-onset schizophrenia are similar to those reported for adult populations, indicating overall continuity between these rare childhood cases and the adult schizophrenia populations.

Blink rate in childhood-onset schizophrenia: comparison with normal and attention-deficit hyperactivity disorder controls.

Several lines of evidence have implicated central dopaminergic pathways in the modulation of blink rate. In the present study, blink rate during smooth pursuit was examined in 17 children with childhood-onset schizophrenia, on and off of clozapine, and compared to that of age-matched normal children and unmedicated children with attention-deficit hyperactivity disorder (ADHD). As has been observed in adolescent and adult schizophrenics, blink rate was significantly higher in schizophrenic children relative to normal and ADHD controls. Within the schizophrenic group, blink rate did not significantly change with the introduction of clozapine and was not related to clinical variables. Blink rate was positively correlated with deterioration in smooth pursuit in normal subjects.

Smooth pursuit eye movements in childhood-onset schizophrenia: comparison with attention-deficit hyperactivity disorder and normal controls.

Abnormalities of the smooth pursuit eye movements of adults with schizophrenia have been well described. We examined smooth pursuit eye movements in schizophrenic children, contrasting them with normal and attention-deficit hyperactivity disorder (ADHD) subjects, to determine whether there is continuity of eye movement dysfunction between childhood- and adult-onset forms of schizophrenia. Seventeen schizophrenic children with onset of illness by age 12, 18 ADHD children, and 22 normal children were studied while engaged in a smooth pursuit eye tracking task. Eye tracking variables were compared across the three groups. Schizophrenic children exhibited significantly greater smooth pursuit impairments than either normal or ADHD subjects. Within the schizophrenic group, there were no significant relationships between eye tracking variables and clinical variables, or ventricular/brain ratio. Childhood-onset schizophrenia is associated with a similar pattern of smooth pursuit abnormalities to that seen in later-onset schizophrenia.

Substance use disorders in patients with posttraumatic stress disorder: a review of the literature.

OBJECTIVE: Alcohol use disorders and other substance use disorders are extremely common among patients with posttraumatic stress disorder (PTSD). This article reviews studies pertaining to the epidemiology, clinical phenomenology, and pathophysiology of comorbid PTSD and substance use disorders. METHOD: Studies were identified by means of computerized and manual searches. The review of research on the pathophysiology of PTSD and substance use disorders was focused on studies of the hypothalamic-pituitary-adrenal axis and the noradrenergic system. RESULTS: High rates of comorbidity suggest that PTSD and substance use disorders are functionally related to one another. Most published data support a pathway whereby PTSD precedes substance abuse or dependence. Substances are initially used to modify PTSD symptoms. With the development of dependence, physiologic arousal resulting from substance withdrawal may exacerbate PTSD symptoms, thereby contributing to a relapse of substance use. Preclinical work has led to the proposal that in PTSD, corticotropin-releasing hormone and noradrenergic systems may interact such that the stress response is progressively augmented. Patients may use sedatives, hypnotics, or alcohol in an effort to interrupt this progressive augmentation. CONCLUSIONS: Vigorous control of withdrawal and PTSD-related arousal symptoms should be sought during detoxification of patients with comorbid PTSD and substance use disorders. Inclusion of patients with comorbid PTSD and substance use disorders in neurobiologic research and in clinical trials will be critical for development of effective treatments for this severely symptomatic patient population.

Quantitative morphology of the caudate and putamen in patients with cocaine dependence.

OBJECTIVE: Deficits in dopaminergic function may contribute to hypertrophy of striatal structures associated with typical neuroleptic treatment. In light of a body of research that has associated chronic cocaine use with extrapyramidal symptoms and striatal dopaminergic depletion, the authors looked for evidence of striatal dysmorphology in patients with chronic cocaine dependence. METHOD: Caudate, putamen, and total brain volumes were quantified by means of magnetic resonance imaging in 25 cocaine-dependent and 20 healthy subjects. RESULTS: Normalized caudate and putamen volumes were 3.40% and 9.18% larger, respectively, in the cocaine-dependent subjects. CONCLUSIONS: These observations suggest that deficits in dopaminergic function associated with cocaine dependence may contribute to striatal hypertrophy.

Smooth pursuit eye-tracking impairment in childhood-onset psychotic disorders.

OBJECTIVE: Although childhood-onset schizophrenia is relatively rare, a sizable group of children with severe emotional disturbances have transient psychotic symptoms that fall outside of current syndrome boundaries. The relationship of this group of children to those with childhood-onset schizophrenia and other childhood psychiatric disorders is unclear. In this study, the authors compared smooth pursuit eye tracking, a biological trait marker associated with schizophrenia, of children and adolescents with psychotic disorder not otherwise specified to that of children with childhood-onset schizophrenia and healthy comparison subjects. METHOD: By means of infrared oculography, smooth pursuit eye movements during a 17 degrees /second visual pursuit task were quantitatively and qualitatively compared in 55 young adolescents (29 with childhood-onset schizophrenia and 26 with psychotic disorder not otherwise specified) and their respective independent healthy comparison groups (a total of 38 healthy subjects). RESULTS: Subjects with childhood-onset schizophrenia had qualitatively poorer eye tracking, higher root mean square error, lower gain, and a greater frequency of catch-up saccades than healthy children. Subjects with psychotic disorder not otherwise specified also had qualitatively poorer eye tracking, higher root mean square error, and lower gain than healthy children, but saccade frequency did not differ significantly. CONCLUSIONS: Children with childhood-onset schizophrenia exhibit a pattern of eye-tracking dysfunction similar to that reported for adult patients. Similar abnormalities were seen in the subjects with psychotic disorder not otherwise specified except that they did not exhibit a greater frequency of catch-up saccades. Prospective longitudinal neurobiological and clinical follow-up studies of both groups are currently underway to further validate the distinction between these two disorders. Also, family studies are planned to establish whether eye-tracking dysfunction represents a trait- or state-related phenomenon in subjects with psychotic disorder not otherwise specified.

Abnormal neurologic maturation in adolescents with early-onset schizophrenia.

OBJECTIVE: This study evaluated neurologic functioning in adolescents with schizophrenia with onset of psychosis before age 13. METHOD: The authors administered a structured neurologic examination to 21 adolescents with early-onset schizophrenia and 27 healthy age- and sex-matched comparison subjects. RESULTS: The adolescents with schizophrenia had a high frequency of neurologic abnormalities. Neurologic signs decreased with age in the healthy comparison subjects but not in the subjects with schizophrenia. CONCLUSIONS: The adolescents with schizophrenia had a high burden of neurologic impairment and a pattern of abnormalities similar to that of adults with schizophrenia. The persistence of neurologic signs in the adolescents with schizophrenia, which faded with age in the healthy comparison adolescents, supports earlier evidence of a delay in or failure of normal brain development during adolescence.

Quantitative morphology of the cerebellum and fourth ventricle in childhood-onset schizophrenia.

OBJECTIVE: Studies have suggested that the maldeveloped neural circuitry producing schizophrenic symptoms may include the cerebellum. The authors found further support for this hypothesis by examining cerebellar morphology in severely ill children and adolescents with childhood-onset schizophrenia. METHOD: Anatomic brain scans were acquired with a 1.5-T magnetic resonance imaging scanner for 24 patients (mean age = 14.1 years, SD = 2.2) with onset of schizophrenia by age 12 (mean age at onset = 10.0 years, SD = 1.9) and 52 healthy children. Volumes of the vermis, inferior posterior lobe, fourth ventricle, and total cerebellum and the midsagittal area of the vermis were measured manually. RESULTS: After adjustment for total cerebral volume, the volume of the vermis and the midsagittal area and volume of the inferior posterior lobe remained significantly smaller in the schizophrenic patients. There was no group difference in total cerebellar or fourth ventricle volume. CONCLUSIONS: These findings are consistent with observations of small vermal size in adult schizophrenia and provide further support for abnormal cerebellar function in childhood- and adult-onset schizophrenia.

Progressive reduction of temporal lobe structures in childhood-onset schizophrenia.

OBJECTIVE: A previous cross-sectional study of brain morphology in childhood-onset schizophrenia indicated sparing of the temporal lobes from processes reducing total cerebral volume in this population. In the present study, subjects with childhood-onset schizophrenia and healthy subjects were rescanned at 2-year follow-up to determine whether this pattern of temporal lobe sparing persists with ongoing illness. METHOD: Anatomic brain magnetic resonance imaging scans were acquired for 10 adolescent patients with average onset of schizophrenia at 10.4 years (SD = 1.7) and 17 healthy adolescents. Scans were obtained on initial admission and at 2-year follow-up by using identical equipment and measurement methodology. RESULTS: Schizophrenic subjects showed significantly greater decreases than healthy subjects in right temporal lobe, bilateral superior temporal gyrus and posterior superior temporal gyrus, right anterior superior temporal gyrus, and left hippocampal volumes during the follow-up interval. Decline in right posterior superior temporal gyrus was associated with high total scores on the Scale for the Assessment of Positive Symptoms at baseline and at follow-up. CONCLUSIONS: Progressive reduction of temporal lobe structures occurs with ongoing illness in childhood-onset schizophrenia.

Including children and adolescents with schizophrenia in medication-free research.

OBJECTIVE: There has been an increasing focus on the ethical issues raised by studies requiring the withdrawal of effective medication in schizophrenic adults. This article examines the risks and benefits of a medication-free period for pediatric patients with treatment-refractory schizophrenia who are participating in an ongoing study. METHOD: Between April 1993 and March 1998, 31 children and adolescents were admitted with a diagnosis of treatment-resistant, childhood-onset schizophrenia. Parental consent was obtained so that patients could participate in a medication-free research period. Patients were evaluated at screening, at the end of a 4-week washout, at the completion of a 6- to 8-week atypical neuroleptic trial, and at a 2- to 4-year follow-up. RESULTS: At the completion of a 4-week drug-free period, seven patients (23%) were diagnosed with another disorder on the basis of data gained from the drug-free period and their lack of schizophrenic symptoms. Their revised diagnoses were posttraumatic stress disorder (N = 1), an atypical psychosis labeled "multidimensionally impaired" (N = 4), and personality disorder (N = 2). At follow-up, three of these patients remained free of neuroleptic therapy. For eight patients (26%), the washout was curtailed because of rapid and severe deterioration of their schizophrenic symptoms. CONCLUSIONS: For children and adolescents with treatment-refractory schizophrenia, a medication-free period can be conducted safely for at least 4 weeks for inpatients. Such trials are useful on clinical grounds and for providing homogeneous patient groups for research. This study also highlights the necessity of having access to hospitalization to observe children and adolescents with psychotic symptoms while medication free.

Elevated central serotonin transporter binding availability in acutely abstinent cocaine-dependent patients.

OBJECTIVE: Recent work has underscored the role of serotonergic neurotransmission in chronic neural adaptations to cocaine dependence. The authors tested for evidence of serotonergic dysfunction during acute abstinence from cocaine, a period of high risk for relapse in cocaine dependence. METHOD: Binding availability of dopamine transporters and serotonin transporters was measured in 15 cocaine-dependent subjects during acute abstinence and in 37 healthy comparison subjects by using [(123)I]beta-CIT and single photon emission computed tomography. RESULTS: Significant increases in diencephalic and brainstem serotonin transporter binding (16.7% and 31.6%, respectively) were observed in cocaine-dependent subjects. Brainstem serotonin transporter binding was significantly inversely correlated with age across diagnostic groups. CONCLUSIONS: These findings provide further evidence of serotonergic dysfunction during acute abstinence from chronic cocaine use. Age-related decline in brainstem serotonin transporter binding may underlie the poor response to selective serotonin reuptake inhibitor antidepressants seen in some elderly depressed patients.

Prediction of dopamine transporter binding availability by genotype: a preliminary report.

OBJECTIVE: Evidence of a relationship between genotype and binding availability was assessed for the dopamine and serotonin transporter genes. METHOD: The authors assessed dopamine transporter genotype at the SLC6A3 3' variable number of tandem repeats (VNTR) polymorphism and serotonin transporter genotype at the SLC6A4 promotor VNTR polymorphism in 30 healthy subjects who also underwent single photon emission computed tomography with [(123)I]beta-CIT. RESULTS: Subjects homozygous for the 10-repeat allele at the SLC6A3 locus demonstrated significantly lower dopamine transporter binding than carriers of the nine-repeat allele. There was no effect of SLC6A4 genotype upon serotonin transporter binding. CONCLUSIONS: These findings suggest that genetic variation at the SLC6A3 3' VNTR polymorphism may modify dopamine transporter function.

Childhood-onset psychotic disorders: magnetic resonance imaging of volumetric differences in brain structure.

OBJECTIVE: Although childhood-onset schizophrenia is rare, children with brief psychotic symptoms and prominent emotional disturbances commonly present diagnostic and treatment problems. Quantitative anatomic brain magnetic resonance images (MRIs) of a subgroup of children with psychotic disorder not otherwise specified were compared with those of children with childhood-onset schizophrenia and healthy comparison subjects. METHOD: Anatomic MRIs were obtained for 71 patients (44 with childhood-onset schizophrenia and 27 with psychotic disorder not otherwise specified) and 106 healthy volunteers. Most patients had been treated with neuroleptics. Volumetric measurements for the cerebrum, anterior frontal region, lateral ventricles, corpus callosum, caudate, putamen, globus pallidus, and midsagittal thalamic area were obtained. RESULTS: Patients had a smaller total cerebral volume than healthy comparison subjects. Analysis of covariance for total cerebral volume and age found that lateral ventricles were larger in both patient groups than in healthy comparison subjects and that schizophrenia patients had a smaller midsagittal thalamic area than both subjects with psychotic disorder not otherwise specified and healthy comparison subjects. CONCLUSIONS: Pediatric patients with psychotic disorder not otherwise specified showed a pattern of brain volumes similar to those found in childhood-onset schizophrenia. Neither group showed a decrease in volumes of temporal lobe structures. Prospective longitudinal magnetic resonance imaging and clinical follow-up studies of both groups are currently underway to further validate the distinction between these two disorders.

Temporal lobe morphology in childhood-onset schizophrenia.

OBJECTIVE: Neurodevelopmental models of schizophrenia imply that a more severe early brain lesion may produce earlier onset of psychotic symptoms. The medial temporal lobes have been proposed as possible locations for such a lesion. The authors tested this hypothesis in a group of children and adolescents with childhood-onset schizophrenia who had severe, chronic symptoms and who were refractory to treatment with typical neuroleptics. METHOD: Anatomic brain magnetic resonance imaging scans were acquired with a 1.5-T scanner for 21 patients (mean age=14.6 years, SD=2.1) who had onset of schizophrenia by age 12 (mean age at onset=10.2, SD=1.5) and 41 normal children. Volumes of the temporal lobe, superior temporal gyrus, amygdala, and hippocampus were measured by manually outlining these structures on contiguous 2-mm thick coronal slices. RESULTS: Patients with childhood-onset schizophrenia had significantly smaller cerebral volumes. With no adjustment for brain volume, no diagnostic differences were observed for any temporal lobe structure. Unexpectedly, with adjustment for total cerebral volume, larger volumes of the superior temporal gyrus and its posterior segment and a trend toward larger temporal lobe volume emerged for the patients with schizophrenia. These patients lacked the normal (right-greater-than-left) hippocampal asymmetry. CONCLUSIONS: These findings do not indicate a more severe medial temporal lobe lesion as the basis of very early onset schizophrenia.

Cerebrospinal fluid monoamine metabolites in childhood-onset schizophrenia.

OBJECTIVE: Pediatric studies of cerebrospinal fluid (CSF) monoamine metabolites in childhood-onset schizophrenia may help to elucidate both pathophysiology and treatment response in early-onset psychosis. METHOD: CSF homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) and serum prolactin were measured during drug-free and antipsychotic medication conditions in 18 patients (mean age = 14.2 years, SD = 1.7) who had onset of schizophrenia by age 12 (mean age at onset = 9.9 years, SD = 1.8). Relationships between changes in CSF monoamines and serum prolactin and clinical outcome were examined, and the degree of change in CSF monoamines in response to clozapine treatment was compared with that for 16 patients with later-onset schizophrenia. RESULTS: Despite patients' significant clinical improvement with treatment, CSF monoamine concentrations and ratios of HVA/5-HIAA and HVA/MHPG did not significantly change with 6 weeks of either haloperidol or clozapine treatment. Serum prolactin levels increased during haloperidol treatment. Clozapine had similar effects on CSF monoamines in patients with childhood- and later-onset schizophrenia. CONCLUSIONS: While these data are compatible with continuity between childhood- and later-onset schizophrenia, they also highlight the complexity of the biochemical events mediating clinical changes in schizophrenia.

Three-dimensional cortical morphometry of the planum temporale in childhood-onset schizophrenia.

OBJECTIVE: Anomalous planum temporale asymmetry has been linked to both schizophrenia and dyslexia. The authors examined the planum temporale of adolescents with childhood-onset schizophrenia who had a high rate of prepsychotic language disorders. METHOD: Planum temporale area and asymmetry were measured in 16 right-handed adolescent patients with schizophrenia who had experienced onset of psychosis by age 12. The same measures were made in 16 healthy adolescents matched for age, sex, and handedness. RESULTS: No differences between the healthy adolescents and those with schizophrenia in planum temporale area or asymmetry were observed. Prepsychotic language disorder predicted abnormal planum temporale asymmetry in the adolescents with schizophrenia. CONCLUSIONS: These findings do not support anomalous planum temporale asymmetry as a basis for psychopathology in childhood-onset schizophrenia.

Cerebellum in attention-deficit hyperactivity disorder: a morphometric MRI study.

Clinical, neuroanatomic, neurobehavioral, and functional brain-imaging studies suggest a role for the cerebellum in cognitive functions, including attention. However, the cerebellum has not been systematically studied in attention-deficit hyperactivity disorder (ADHD). We quantified the cerebellar and vermal volumes, and the midsagittal areas of three vermal regions, from MRIs of 46 right-handed boys with ADHD and 47 matched healthy controls. Vermal volume was significantly less in the boys with ADHD. This reduction involved mainly the posterior inferior lobe (lobules VIII to X) but not the posterior superior lobe (lobules VI to VII). These results remained significant even after adjustment for brain volume and IQ. A cerebello-thalamo-prefrontal circuit dysfunction may subserve the motor control, inhibition, and executive function deficits encountered in ADHD.

Chromosome 22q11.2 interstitial deletions among childhood-onset schizophrenics and "multidimensionally impaired".

Since its first description almost a century ago schizophrenia with childhood onset, a rare yet devastating disorder, has been diagnosed in children as young as age 5. Recently, the velocardiofacial syndrome, whose underlying cause is interstitial deletions of 22q11.2, was found in 2 of 100 cases of schizophrenics with adult onset [Karayiorgou et al., Proc Natl Acad Sci USA 92: 7612-7616, 1995]. No study has documented the prevalence of velocardiofacial syndrome and the 22q11.2 deletion in a population of schizophrenics with childhood onset. Here we describe the result of such a study in a sample originally selected for a trial of atypical antipsychotic drugs. A separate group of patients was also included in the study; they can best be accounted for as a variant of childhood-onset schizophrenia (COS) and had been provisionally termed "multidimensionally impaired." Fluorescent in situ hybridization screening of 32 COS and 21 multidimensionally impaired patients revealed 1 COS patient with an interstitial deletion spanning at least 2.5 megabases.