Whole-genome association analysis of treatment response in obsessive-compulsive disorder

Up to 30% of patients with obsessive-compulsive disorder (OCD) exhibit an inadequate response to serotonin reuptake inhibitors (SRIs). To date, genetic predictors of OCD treatment response have not been systematically investigated using genome-wide association study (GWAS). To identify specific genetic variations potentially influencing SRI response, we conducted a GWAS study in 804 OCD patients with information on SRI response. SRI response was classified as 'response' (n=514) or 'non-response' (n=290), based on self-report. We used the more powerful Quasi-Likelihood Score Test (the MQLS test) to conduct a genome-wide association test correcting for relatedness, and then used an adjusted logistic model to evaluate the effect size of the variants in probands. The top single-nucleotide polymorphism (SNP) was rs17162912 (P=1.76 × 10(-8)), which is near the DISP1 gene on 1q41-q42, a microdeletion region implicated in neurological development. The other six SNPs showing suggestive evidence of association (P<10(-5)) were rs9303380, rs12437601, rs16988159, rs7676822, rs1911877 and rs723815. Among them, two SNPs in strong linkage disequilibrium, rs7676822 and rs1911877, located near the PCDH10 gene, gave P-values of 2.86 × 10(-6) and 8.41 × 10(-6), respectively. The other 35 variations with signals of potential significance (P<10(-4)) involve multiple genes expressed in the brain, including GRIN2B, PCDH10 and GPC6. Our enrichment analysis indicated suggestive roles of genes in the glutamatergic neurotransmission system (false discovery rate (FDR)=0.0097) and the serotonergic system (FDR=0.0213). Although the results presented may provide new insights into genetic mechanisms underlying treatment response in OCD, studies with larger sample sizes and detailed information on drug dosage and treatment duration are needed.

Dependent personality, separation anxiety disorder and other anxiety disorders in OCD

BACKGROUND

The purpose of this study was to investigate whether dependent personality and/or general personality dimensions might explain the strong relationships between separation anxiety disorder (Sep-AD) and three other anxiety disorders (agoraphobia, panic disorder and social anxiety disorder) in individuals with obsessive compulsive disorder (OCD).

METHODS

Using data from 509 adult participants collected during the OCD Collaborative Genetic Study, we used logistic regression models to evaluate the relationships between Sep-AD, dependent personality score, general personality dimensions and three additional anxiety disorders.

RESULTS

The dependent personality score was strongly associated with Sep-AD and the other anxiety disorders in models adjusted for age at interview, age at onset of OC symptoms and worst ever OCD severity score. Several general personality dimensions, especially neuroticism, extraversion and conscientiousness, were also related to Sep-AD and the other anxiety disorders. Sep-AD was not independently related to these anxiety disorders, in multivariate models including general personality and dependent personality disorder scores.

CONCLUSIONS

The results suggest that Sep-AD in childhood and these other anxiety disorders in adulthood are consequences of dependent personality disorder (for agoraphobia and panic disorder) or introversion (for social phobia). It is unknown whether these results would be similar in a non-OCD sample.

Positive effects of methylphenidate on hyperactivity are moderated by monoaminergic gene variants in children with autism spectrum disorders

Methylphenidate (MPH) reduces hyperactive-impulsive symptoms common in children with autism spectrum disorders (ASDs), however, response and tolerability varies widely. We hypothesized monoaminergic gene variants may moderate MPH effects in ASD, as in typically developing children with attention-deficit/hyperactivity disorder. Genotype data were available for 64 children with ASD and hyperactivity who were exposed to MPH during a 1-week safety/tolerability lead-in phase and 58 who went on to be randomized to placebo and three doses of MPH during a 4-week blinded, crossover study. Outcome measures included the Clinical Global Impression-Improvement (CGI-I) scale and the Aberrant Behavior Checklist (ABC-hyperactivity index). A total of 14 subjects discontinued the study because of MPH side effects. Subjects were genotyped for variants in DRD1-DRD5, ADRA2A, SLC6A3, SLC6A4, MAOA and MAOB, and COMT. Forty-nine percent of the sample met positive responder criteria. In this modest but relatively homogeneous sample, significant differences by DRD1 (P=0.006), ADRA2A (P<0.02), COMT (P<0.04), DRD3 (P<0.05), DRD4 (P<0.05), SLC6A3 (P<0.05) and SLC6A4 (P<0.05) genotypes were found for responders versus non-responders. Variants in DRD2 (P<0.001) and DRD3 (P<0.04) were associated with tolerability in the 14 subjects who discontinued the trial. For this first MPH pharmacogenetic study in children with ASD, multiple monoaminergic gene variants may help explain individual differences in MPH's efficacy and tolerability.

Meta-analysis of association between obsessive-compulsive disorder and the 3' region of neuronal glutamate transporter gene SLC1A1

The neuronal glutamate transporter gene SLC1A1 is a candidate gene for obsessive-compulsive disorder (OCD) based on linkage studies and convergent evidence implicating glutamate in OCD etiology. The 3' end of SLC1A1 is the only genomic region with consistently demonstrated OCD association, especially when analyzing male-only probands. However, specific allele associations have not been consistently replicated, and recent OCD genome-wide association and meta-analysis studies have not incorporated all previously associated SLC1A1 SNPs. To clarify the nature of association between SLC1A1 and OCD, pooled analysis was performed on all available relevant raw study data, comprising a final sample of 815 trios, 306 cases and 634 controls. This revealed weak association between OCD and one of nine tested SLC1A1 polymorphisms (rs301443; uncorrected P = 0.046; non-significant corrected P). Secondary analyses of male-affecteds only (N = 358 trios and 133 cases) demonstrated modest association between OCD and a different SNP (rs12682807; uncorrected P = 0.012; non-significant corrected P). Findings of this meta-analysis are consistent with the trend of previous candidate gene studies in psychiatry and do not clarify the putative role of SLC1A1 in OCD pathophysiology. Nonetheless, it may be important to further examine the potential associations demonstrated in this amalgamated sample, especially since the SNPs with modest associations were not included in the more highly powered recent GWAS or in a past meta-analysis including five SLC1A1 polymorphisms. This study underscores the need for much larger sample sizes in future genetic association studies and suggests that next-generation sequencing may be beneficial in examining the potential role of rare variants in OCD.

Homeobox genes in obsessive-compulsive disorder

BACKGROUND

Despite evidence that obsessive-compulsive disorder (OCD) is a familial neuropsychiatric condition, progress aimed at identifying genetic determinants of the disorder has been slow. The OCD Collaborative Genetics Study (OCGS) has identified several OCD susceptibility loci through linkage analysis.

METHODS

In this study we investigate two regions on chromosomes 15q and 1q by first refining the linkage region using additional short tandem repeat polymorphic (STRP) markers. We then performed association analysis on single nucleotide polymorphisms (SNP) genotyped (markers placed every 2-4 kb) in the linkage regions in the OCGS sample of 376 rigorously phenotyped affected families.

RESULTS

Three SNPs are most strongly associated with OCD: rs11854486 (P = 0.00005 [0.046 after adjustment for multiple tests]; genetic relative risk (GRR) = 11.1 homozygous and 1.6 heterozygous) and rs4625687 [P = 0.00007 (after adjustment = 0.06); GRR = 2.4] on 15q; and rs4387163 (P = 0.0002 (after adjustment = 0.08); GRR = 1.97) on 1q. The first SNP is adjacent to NANOGP8, the second SNP is in MEIS2, and the third is 150 kb between PBX1 and LMX1A.

CONCLUSIONS

All the genes implicated by association signals are homeobox genes and are intimately involved in neurodevelopment. PBX1 and MEIS2 exert their effects by the formation of a heterodimeric complex, which is involved in development of the striatum, a brain region involved in the pathophysiology of OCD. NANOGP8 is a retrogene of NANOG, a homeobox transcription factor known to be involved in regulation of neuronal development. These findings need replication; but support the hypothesis that genes involved in striatal development are implicated in the pathogenesis of OCD.

Is obsessive-compulsive disorder an anxiety disorder, and what, if any, are spectrum conditions? A family study perspective

BACKGROUND

Experts have proposed removing obsessive-compulsive disorder (OCD) from the anxiety disorders section and grouping it with putatively related conditions in DSM-5. The current study uses co-morbidity and familiality data to inform these issues.

METHOD

Case family data from the OCD Collaborative Genetics Study (382 OCD-affected probands and 974 of their first-degree relatives) were compared with control family data from the Johns Hopkins OCD Family Study (73 non-OCD-affected probands and 233 of their first-degree relatives).

RESULTS

Anxiety disorders (especially agoraphobia and generalized anxiety disorder), cluster C personality disorders (especially obsessive-compulsive and avoidant), tic disorders, somatoform disorders (hypochondriasis and body dysmorphic disorder), grooming disorders (especially trichotillomania and pathological skin picking) and mood disorders (especially unipolar depressive disorders) were more common in case than control probands; however, the prevalences of eating disorders (anorexia and bulimia nervosa), other impulse-control disorders (pathological gambling, pyromania, kleptomania) and substance dependence (alcohol or drug) did not differ between the groups. The same general pattern was evident in relatives of case versus control probands. Results in relatives did not differ markedly when adjusted for demographic variables and proband diagnosis of the same disorder, though the strength of associations was lower when adjusted for OCD in relatives. Nevertheless, several anxiety, depressive and putative OCD-related conditions remained significantly more common in case than control relatives when adjusting for all of these variables simultaneously.

CONCLUSIONS

On the basis of co-morbidity and familiality, OCD appears related both to anxiety disorders and to some conditions currently classified in other sections of DSM-IV.

A screen of SLC1A1 for OCD-related alleles

SLC1A1, which encodes the neuronal and epithelial glutamate transporter, is a promising candidate gene for obsessive-compulsive disorder (OCD). In this study, we conducted capillary electrophoresis single-strand conformation polymorphism (CE-SSCP) screen for all 12 identified exons, including all coding regions and approximately 50 bp of flanking introns of the human SLC1A1 in 378 OCD-affected individuals. Full sequencing was completed on samples that showed an aberrant SSCP tracing for identification of the underlying sequence variants. Our aim was to determine if there are differences in the frequencies of relatively common alleles, or rare functional alleles, in 378 OCD cases and 281 ethnically matched controls. We identified one nonsynonymous coding SNP (c.490A > G, T164A) and three synonymous coding SNP (c.81G > C, A27A; c.414A > G, T138T; c.1110T > C, T370T) in case samples. We found no statistical differences in genotype and allele frequencies of common cSNPs in SLC1A1 between the OCD cases and controls. The rare variant T164A was found only in one family. Further investigation of this variant is necessary to determine whether and how it is related to OCD. There was no other evidence of significant accumulation of deleterious coding mutations in SLC1A1 in the OCD cases.

A family-based association study of the glutamate transporter gene SLC1A1 in obsessive-compulsive disorder in 378 families

SLC1A encodes the neuronal and epithelial glutamate transporter and was previously tested as a candidate for obsessive-compulsive disorder (OCD) by several research groups. Recently, three independent research groups reported significant association findings between OCD and several genetic variants in SLC1A1. This study reports the results from a family-based association study, which examined the association between 13 single nucleotide polymorphisms (SNPs) within or in proximity to the SLC1A1 gene. Although we did not replicate association findings for those significant SNPs reported by previous studies, our study indicated a strong association signal with the SNP RS301443 (P-value = 0.000067; Bonferroni corrected P-value = 0.0167) under a dominant model, with an estimated odds ratio of 3.5 (confidence interval: 2.66-4.50). Further, we conducted single SNP analysis after stratifying the full data set by the gender status of affected in each family. The P-value for RS301443 in families with the male affected was 0.00027, and the P-value in families with female affected was 0.076. The fact that we identified a signal which was not previously reported by the other research groups may be due to differences in study designs and sample ascertainment. However, it is also possible that this significant SNP may be part of a regulator for SLC1A1, given that it is roughly 7.5 kb away from the boundary of the SLC1A1 gene. However, this potential finding needs to be validated biologically. Further functional studies in this region are planned by this research group.

Obsessive-compulsive disorder: subclassification based on co-morbidity

BACKGROUND

Obsessive-compulsive disorder (OCD) is probably an etiologically heterogeneous condition. Many patients manifest other psychiatric syndromes. This study investigated the relationship between OCD and co-morbid conditions to identify subtypes.

METHOD

Seven hundred and six individuals with OCD were assessed in the OCD Collaborative Genetics Study (OCGS). Multi-level latent class analysis was conducted based on the presence of eight co-morbid psychiatric conditions [generalized anxiety disorder (GAD), major depression, panic disorder (PD), separation anxiety disorder (SAD), tics, mania, somatization disorders (Som) and grooming disorders (GrD)]. The relationship of the derived classes to specific clinical characteristics was investigated.

RESULTS

Two and three classes of OCD syndromes emerge from the analyses. The two-class solution describes lesser and greater co-morbidity classes and the more descriptive three-class solution is characterized by: (1) an OCD simplex class, in which major depressive disorder (MDD) is the most frequent additional disorder; (2) an OCD co-morbid tic-related class, in which tics are prominent and affective syndromes are considerably rarer; and (3) an OCD co-morbid affective-related class in which PD and affective syndromes are highly represented. The OCD co-morbid tic-related class is predominantly male and characterized by high conscientiousness. The OCD co-morbid affective-related class is predominantly female, has a young age at onset, obsessive-compulsive personality disorder (OCPD) features, high scores on the 'taboo' factor of OCD symptoms, and low conscientiousness.

CONCLUSIONS

OCD can be classified into three classes based on co-morbidity. Membership within a class is differentially associated with other clinical characteristics. These classes, if replicated, should have important implications for research and clinical endeavors.

Sapap3 and pathological grooming in humans: Results from the OCD collaborative genetics study

SAP90/PSD95-associated protein (SAPAP) family proteins are post-synaptic density (PSD) components that interact with other proteins to form a key scaffolding complex at excitatory (glutamatergic) synapses. A recent study found that mice with a deletion of the Sapap3 gene groomed themselves excessively, exhibited increased anxiety-like behaviors, and had cortico-striatal synaptic defects, all of which were preventable with lentiviral-mediated expression of Sapap3 in the striatum; the behavioral abnormalities were also reversible with fluoxetine. In the current study, we sought to determine whether variation within the human Sapap3 gene was associated with grooming disorders (GDs: pathologic nail biting, pathologic skin picking, and/or trichotillomania) and/or obsessive-compulsive disorder (OCD) in 383 families thoroughly phenotyped for OCD genetic studies. We conducted family-based association analyses using the FBAT and GenAssoc statistical packages. Thirty-two percent of the 1,618 participants met criteria for a GD, and 65% met criteria for OCD. Four of six SNPs were nominally associated (P < 0.05) with at least one GD (genotypic relative risks: 1.6-3.3), and all three haplotypes were nominally associated with at least one GD (permuted P < 0.05). None of the SNPs or haplotypes were significantly associated with OCD itself. We conclude that Sapap3 is a promising functional candidate gene for human GDs, though further work is necessary to confirm this preliminary evidence of association.

Potential adverse effects of amphetamine treatment on brain and behavior: a review

Amphetamine stimulants have been used medically since early in the twentieth century, but they have a high abuse potential and can be neurotoxic. Although they have long been used effectively to treat attention deficit hyperactivity disorder (ADHD) in children and adolescents, amphetamines are now being prescribed increasingly as maintenance therapy for ADHD and narcolepsy in adults, considerably extending the period of potential exposure. Effects of prolonged stimulant treatment have not been fully explored, and understanding such effects is a research priority. Because the pharmacokinetics of amphetamines differ between children and adults, reevaluation of the potential for adverse effects of chronic treatment of adults is essential. Despite information on the effects of stimulants in laboratory animals, profound species differences in susceptibility to stimulant-induced neurotoxicity underscore the need for systematic studies of prolonged human exposure. Early amphetamine treatment has been linked to slowing in height and weight growth in some children. Because the number of prescriptions for amphetamines has increased several fold over the past decade, an amphetamine-containing formulation is the most commonly prescribed stimulant in North America, and it is noteworthy that amphetamines are also the most abused prescription medications. Although early treatment does not increase risk for substance abuse, few studies have tracked the compliance and usage profiles of individuals who began amphetamine treatment as adults. Overall, there is concern about risk for slowed growth in young patients who are dosed continuously, and for substance abuse in patients first medicated in late adolescence or adulthood. Although most adult patients also use amphetamines effectively and safely, occasional case reports indicate that prescription use can produce marked psychological adverse events, including stimulant-induced psychosis. Assessments of central toxicity and adverse psychological effects during late adulthood and senescence of adults who receive prolonged courses of amphetamine treatment are warranted. Finally, identification of the biological factors that confer risk and those that offer protection is also needed to better specify the parameters of safe, long-term, therapeutic administration of amphetamines to adults.

Gender differences in genetic linkage and association on 11p15 in obsessive-compulsive disorder families

Several clinical and genetic studies have reported gender differences in obsessive-compulsive disorder (OCD). Previously, we conducted a linkage genome scan using multipoint allele-sharing methods to test for linkage in 219 families participating in the OCD Collaborative Genetics Study. When these families were stratified by proband's gender, suggestive linkage to chromosome 11p15 at marker D11S2362 (KAC(all) = 2.92, P = 0.00012) was detected in families with male probands, but not in the ones with female probands. We have since conducted fine mapping with a denser microsatellite marker panel in the region of 11p15, and detected a significant linkage signal at D11S4146 (KAC(all) = 5.08, P < 0.00001) in the families of male probands. Subsequently, 632 SNPs were genotyped spanning a 4.0 Mb region of the 1 LOD unit interval surrounding the linkage peak in the original families and an additional 165 families. Six SNPs were associated with OCD (P < 0.001): two SNPs were identified when all the families were included, and four SNPs only in male proband families. No SNP showed significant association with the OCD phenotype only in the families with a female proband. The results suggest a possible gender effect in the etiology of OCD.

Genomewide linkage scan for obsessive-compulsive disorder: evidence for susceptibility loci on chromosomes 3q, 7p, 1q, 15q, and 6q

Obsessive-compulsive disorder (OCD) is the tenth most disabling medical condition worldwide. Twin and family studies implicate a genetic etiology for this disorder, although specific genes have yet to be identified. Here, we present the first large-scale model-free linkage analysis of both extended and nuclear families using both 'broad' (definite and probable diagnoses) and 'narrow' (definite only) definitions of OCD. We conducted a genome-scan analysis of 219 families collected as part of the OCD Collaborative Genetics Study. Suggestive linkage signals were revealed by multipoint analysis on chromosomes 3q27-28 (P=0.0003), 6q (P=0.003), 7p (P=0.001), 1q (P=0.003), and 15q (P=0.006). Using the 'broad' OCD definition, we observed the strongest evidence for linkage on chromosome 3q27-28. The maximum overall Kong and Cox LODall score (2.67) occurred at D3S1262 and D3S2398, and simulation based P-values for these two signals were 0.0003 and 0.0004, respectively, although for both signals, the simulation-based genome-wide significance levels were 0.055. Covariate-linkage analyses implicated a possible role of gene(s) on chromosome 1 in increasing the risk for an earlier onset form of OCD. We are currently pursuing fine mapping in the five regions giving suggestive signals, with a particular focus on 3q27-28. Given probable etiologic heterogeneity in OCD, mapping gene(s) involved in the disorder may be enhanced by replication studies, large-scale family-based linkage studies, and the application of novel statistical methods.

Transmission disequilibrium testing of dopamine-related candidate gene polymorphisms in ADHD: confirmation of association of ADHD with DRD4 and DRD5

Attention-deficit hyperactivity disorder (ADHD) is one of the most common childhood behavioral disorders. Genetic factors contribute to the underlying liability to develop ADHD. Reports implicate variants of genes important for the synthesis, uptake, transport and receptor binding of dopamine in the etiology of ADHD, including DRD4, DAT1, DRD2, and DRD5. In the present study, we genotyped a large multiplex sample of ADHD affected children and their parents for polymorphisms in genes previously reported to be associated with ADHD. Associations were tested by the transmission disequilibrium test (TDT). The sample is sufficient to detect genotype relative risks (GRRs) for putative risk alleles. The DRD4 gene 120-bp insertion/deletion promoter polymorphism displayed a significant bias in transmission of the insertion (chi(2)=7.58, P=0.006) as suggested by an analysis of a subset of these families. The seven repeat allele of the DRD4 48-bp repeat polymorphism (DRD4.7) was not significantly associated with ADHD in the large sample in contrast to our earlier findings in a smaller subset. We replicate an association of a dinucleotide repeat polymorphism near the DRD5 gene with ADHD by showing biased nontransmission of the 146-bp allele (P=0.02) and a trend toward excess transmission of the 148-bp allele (P=0.053). No evidence for an association was found for polymorphisms in DRD2 or DAT1 in this sample. The DRD5 146-bp (DRD5.146) allele and the DRD4 240-bp (DRD4.240) allele of the promoter polymorphism emerge as the two DNA variants showing a significant association in this large sample of predominantly multiplex families with ADHD, with estimated GRRs of 1.7 and 1.37, respectively.

Genome-wide scan of reading ability in affected sibling pairs with attention-deficit/hyperactivity disorder: unique and shared genetic effects

Attention-deficit/hyperactivity disorder (ADHD) and reading disability (RD) are common highly heritable disorders of childhood, which frequently co-occur. Data from twin and family studies suggest that this overlap is, in part, due to shared genetic underpinnings. Here, we report the first genome-wide linkage analysis of measures of reading ability in children with ADHD, using a sample of 233 affected sibling pairs who previously participated in a genome-wide scan for susceptibility loci in ADHD. Quantitative trait locus (QTL) analysis of a composite reading factor defined from three highly correlated reading measures identified suggestive linkage (multipoint maximum lod score, MLS>2.2) in four chromosomal regions. Two regions (16p, 17q) overlap those implicated by our previous genome-wide scan for ADHD in the same sample: one region (2p) provides replication for an RD susceptibility locus, and one region (10q) falls approximately 35 cM from a modestly highlighted region in an independent genome-wide scan of siblings with ADHD. Investigation of an individual reading measure of Reading Recognition supported linkage to putative RD susceptibility regions on chromosome 8p (MLS=2.4) and 15q (MLS=1.38). Thus, the data support the existence of genetic factors that have pleiotropic effects on ADHD and reading ability--as suggested by shared linkages on 16p, 17q and possibly 10q--but also those that appear to be unique to reading--as indicated by linkages on 2p, 8p and 15q that coincide with those previously found in studies of RD. Our study also suggests that reading measures may represent useful phenotypes in ADHD research. The eventual identification of genes underlying these unique and shared linkages may increase our understanding of ADHD, RD and the relationship between the two.

Biased paternal transmission of SNAP-25 risk alleles in attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) is the most common childhood psychiatric disorder, affecting 5-10% of school-age children. Although the biological basis of this disorder is unknown, twin and family studies provide strong evidence that ADHD has a genetic basis involving multiple genes. A previous study found an association between ADHD and two polymorphisms in the 3' untranslated region (UTR) of SNAP-25, a gene encoding a synaptic vesicle docking protein known to play a role in the hyperactivity observed in the Coloboma mouse strain. In this paper, we test biased transmission of the 3' UTR SNAP-25 haplotype using a larger ADHD sample of 113 families with 207 affected children. Using the transmission disequilibrium test (TDT), we found a trend consistent with biased transmission of the TC haplotype of SNAP-25 in all transmissions and detected a significant distortion (P=0.027) when paternal transmissions were evaluated.

Medial temporal lobe in childhood-onset schizophrenia

The majority of anatomic and neuroimaging studies in adult-onset schizophrenia demonstrate decreased volumes of the medial temporal lobe when compared with findings in normal individuals. The goal of this study was to investigate the hypothesis that subjects with childhood-onset schizophrenia would show decreased volumes of the medial temporal lobe when compared to normal children. Thirteen children meeting DSM-III-R criteria for schizophrenia (mean age 14.2+/-3.8 years) and 20 normal children (mean age 12.0+/-2.8 years) were investigated. MRI scans were performed on a 1.5-T GE Signa MR scanner using a coronal plane SPGR at 1.4-mm slice thickness. Volumes were assessed by manually tracing bilateral hippocampus, amygdala and temporal lobes. After adjustment for age and total brain volume, the amygdala was significantly larger in the schizophrenics than in the control subjects, and this volume increase was more pronounced on the left side. Hippocampus volumes did not differ significantly across groups. There was a nearly significant left-greater-than-right asymmetry of the amygdala in the schizophrenic group but not in the normal group. A nearly significant right-greater-than-left asymmetry was found in the anterior hippocampus for both schizophrenic and control groups. These findings are consistent with previous reports of at least initial sparing of temporal lobe regions in childhood-onset schizophrenia.

Mapping cortical asymmetry and complexity patterns in normal children

This study reports the first comprehensive three-dimensional (3D) maps of cortical patterns in children. Using a novel parametric mesh-based analytic technique applied to high-resolution T1-weighted MRI scans, we examined age (6-16 years) and gender differences in cortical complexity (the fractal dimension or complexity of sulcal/gyral convolutions) and asymmetry of 24 primary cortical sulci in normally developing children (N=24). Three-dimensional models of the cerebral cortex were extracted and major sulci mapped in stereotaxic space. Given the documented age-related changes in frontal lobe functions and several neuroimaging studies that have reported accompanying volumetric changes in these regions, we hypothesized that, with age, we would find continued modifications of the cerebrum in frontal cortex. We also predicted that phylogenetically older regions of the cerebrum, such as olfactory cortex, would be less variable in anatomic location across subjects and with age. Age-related increases in cortical complexity were found in both left and right inferior frontal and left superior frontal regions, possibly indicating an increase in secondary branching with age in these regions. Moreover, a significant increase in the length of the left inferior frontal sulcus and a posterior shifting of the left pre-central sulcus was associated with age. Three-dimensional asymmetry and anatomic variability maps revealed a significant left-greater-than-right asymmetry of the Sylvian fissures and superior temporal sulci, and increased variance in dorsolateral frontal and perisylvian areas relative to ventral regions of the cortex. These results suggest increases in cortical complexity and subtle modifications of sulcal topography of frontal lobe regions, likely reflecting ongoing processes such as myelination and synaptic remodeling that continue into the second decade of life. More studies in a larger sample set and/or longitudinal design are needed to address the issues of normal individual variation and sulcal development.

Mental health problems and service use among female juvenile offenders: their relationship to criminal history

OBJECTIVE

To describe (1) the level of mental health problems and lifetime use of specialty mental health services and special education programs among incarcerated female juvenile offenders and (2) how these indices relate to their criminal history.

METHOD

Between 1997 and 1998, fifty-four female youths incarcerated in California were interviewed on-site using standardized self-report measures of depression and anxiety symptoms and substance use problems.

RESULTS

Eighty percent of the youths had symptoms of an emotional disorder or substance use problem, and almost two thirds (63%) had a history of recidivism. Of those with emotional symptoms or a substance use problem, 51% had used specialty mental health services and 58% had been in a special education program during their lifetime. In addition, among recidivistic youths, 82% had a history of a substance use problem and 47% had used specialty mental health services during their lifetime.

CONCLUSIONS

A substantial proportion of female juvenile offenders merit a mental health evaluation. Interventions for these high-risk youths should include an assessment for substance use disorders because of the association of recidivism and substance use problems in this population.

Attention-deficit/hyperactivity disorder: perspectives from neuroimaging

Attention-deficit/hyperactivity disorder (ADHD) is a common childhood behavioral disorder most often characterized by inattentiveness, impulsivity, and hyperactivity. Current etiologic theories suggest that ADHD stems from abnormalities in dopaminergic and possibly noradrenergic brainstem nuclei that act to regulate a cortico-striato-thalamo-cortical network, believed to be critical for executive functions and the regulation of behavioral responses such as arousal, attention, and inhibition. Noninvasive structural and functional neuroimaging techniques provide a new avenue for exploring the validity of these theories. Despite their limitations, neuroimaging studies have provided a unique and otherwise inaccessible, biological perspective of ADHD. Collectively, the studies reviewed here reveal that dysfunction in arousal, behavioral inhibition, and attention associated with ADHD may result from structural abnormalities in frontostriatal regions that in turn result in diminished activity essential for normal function.

Evidence for linkage of a tandem duplication polymorphism upstream of the dopamine D4 receptor gene (DRD4) with attention deficit hyperactivity disorder (ADHD)

Attention deficit hyperactivity disorder (ADHD) is a common childhood-onset neurodevelopmental disorder. Evidence from twin, adoption, and family studies provide support for a genetic contribution to the etiology of ADHD. Several candidate gene studies have identified an association between a 7-repeat variant in exon 3 of the dopamine 4 receptor gene (DRD4) and ADHD. However, in spite of the positive reports finding association of the exon 3 VNTR with ADHD, several other polymorphisms within DRD4 have been identified that conceivably could contribute to risk for ADHD. Recently, another common polymorphism of the DRD4 gene has been described involving a 120-bp repeat element upstream of the 5' transcription initiation site. In this report, we describe results of analysis of the DRD4 120-bp repeat promoter polymorphism in a sample of 371 children with ADHD and their parents, using the transmission disequilibrium test (TDT). Results showed a significant preferential transmission of the 240-bp (long) allele with ADHD. Exploratory analyses of the Inattentive phenotypic subtype of ADHD strengthened the evidence for linkage. These data add further support for the role of DRD4 variants conferring increased risk for ADHD, and imply that additional studies of DRD4 and other related genes are needed.

Familial clustering of symptoms and disruptive behaviors in multiplex families with attention-deficit/hyperactivity disorder

OBJECTIVE

To examine familial clustering of attention-deficit/hyperactivity disorder (ADHD), ADHD subtypes, symptoms, and oppositional behaviors in affected sibling pairs (ASPs) and their parents.

METHOD

One hundred thirty-two ASPs, ranging in age from 5 to 25 years and ascertained through clinic and volunteer referrals, were examined for DSM-IV ADHD subtypes, oppositional defiant disorder (ODD), and conduct disorder (CD) with the Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime version (K-SADS-PL). Two hundred fifty-six parents in these families were assessed by means of the SADS-Lifetime version, Modified for the Study of Anxiety Disorders, Updated for DSM-IV (SADS-LA-IV), and the Behavioral Disorders supplement of the K-SADS-PL to determine ADHD, ODD, and CD.

RESULTS

Fifty-five percent of families ascertained through an ASP have at least one parent with a lifetime diagnosis of ADHD. The frequency of ADHD in at least one parent was higher in families with at least one affected girl (63%) than in families with only affected boys (45%) (p = .02). There was no evidence that affected siblings or parents within ASP families showed similar patterns of ADHD symptoms, such as ADHD subtype classification. In contrast, CD significantly clustered in ASP families.

CONCLUSIONS

The sex difference in prevalence of ADHD among ASPs is consistent with a model of inheritance in which girls require a greater loading of familial influences to develop ADHD. The lack of familial clustering of ADHD symptoms within ASP families suggests that hyperactive and inattentive symptoms reflect common familial underpinnings and not unique familial effects. In contrast, CD seems to reflect unique familial underpinnings distinct from those underlying ADHD.

Assessment of attention deficit hyperactivity disorder: a review of recent literature

Attention deficit hyperactivity disorder is one of the most common behavioral disorders of childhood and is frequently assessed and treated by pediatricians and other primary care physicians. The diagnosis of attention deficit hyperactivity disorder is based on the careful synthesis of clinical data derived from multiple sources, notably, the patient, parents, and teachers. Standard behavioral rating scales simplify and standardize collection of clinical data but by themselves are not sufficient for a diagnosis. Recognition and treatment of disorders comorbid with attention deficit hyperactivity disorder are necessary for optimal outcomes. Psychoeducational testing is useful in the assessment of suspected associated learning disabilities, but there is no evidence at present to support use of psychologic testing, laboratory measures of attention, electroencephalography, or neuroimaging studies in the clinical assessment of attention deficit hyperactivity disorder.

The Texas Children's Medication Algorithm Project: Report of the Texas Consensus Conference Panel on Medication Treatment of Childhood Attention-Deficit/Hyperactivity Disorder. Part I. Attention-Deficit/Hyperactivity Disorder

OBJECTIVES

Expert consensus methodology was used to develop evidence-based, consensually agreed-upon medication treatment algorithms for attention-deficit/hyperactivity disorder (ADHD) in the public mental health sector. Although treatment algorithms for adult mental disorders have been developed, this represents one of the first attempts to develop similar algorithms for childhood mental disorders. Although these algorithms were developed initially for the public sector, the goals of this approach are to increase the uniformity of treatment and improve the clinical outcomes of children and adolescents with ADHD in a variety of treatment settings.

METHOD

A consensus conference of academic clinicians and researchers, practicing clinicians, administrators, consumers, and families was convened to develop evidence-based consensus algorithms for the pharmacotherapy of childhood ADHD. After a series of presentations of current research evidence and panel discussion, the consensus panel met and drafted the algorithms along with guidelines for implementation.

RESULTS

The panel developed consensually agreed-upon algorithms for ADHD with and without specific comorbid disorders. The algorithms consist of systematic strategies for psychopharmacological interventions and tactics to ensure successful implementation of the strategies. While the algorithms focused on the medication management of ADHD, the conference emphasized that psychosocial treatments are often a critical component of the overall management of ADHD.

CONCLUSIONS

Medication algorithms for ADHD can be developed with consensus. A companion article will discuss the implementation of these algorithms.

The Texas Children's Medication Algorithm Project: Report of the Texas Consensus Conference Panel on Medication Treatment of Childhood Attention-Deficit/Hyperactivity Disorder. Part II: Tactics. Attention-Deficit/Hyperactivity Disorder

OBJECTIVES

Expert consensus methodology was used to develop a medication treatment algorithm for attention-deficit/hyperactivity disorder (ADHD). The algorithm broadly outlined the choice of medication for ADHD and some of its most common comorbid conditions. Specific tactical recommendations were developed with regard to medication dosage, assessment of drug response, management of side effects, and long-term medication management.

METHOD

The consensus conference of academic clinicians and researchers, practicing clinicians, administrators, consumers, and families developed evidence-based tactics for the pharmacotherapy of childhood ADHD and its common comorbid disorders. The panel discussed specifics of treatment of ADHD and its comorbid conditions with stimulants, antidepressants, mood stabilizers, alpha-agonists, and (when appropriate) antipsychotics.

RESULTS

Specific tactics for the use of each of the above agents are outlined. The tactics are designed to be practical for implementation in the public mental health sector, but they may have utility in many practice settings, including the private practice environment.

CONCLUSIONS

Tactics for psychopharmacological management of ADHD can be developed with consensus.

Assessment in multisite randomized clinical trials of patients with autistic disorder: the Autism RUPP Network. Research Units on Pediatric Psychopharmacology

Assessment of autistic disorder (autism) symptoms, primary and secondary, poses more challenging problems than ordinarily found in multisite randomized clinical trial (RCT) assessments. For example, subjects may be uncommunicative and extremely heterogeneous in problem presentation, and current pharmacological treatments are not likely to alter most core features of autism. The Autism Research Units on Pediatric Psychopharmacology (RUPP Autism Network) resolved some of these problems during the design of a risperidone RCT in children/adolescents. The inappropriateness of the usual anchors for a Clinical Global Impression of Severity (CGI-S) was resolved by defining uncomplicated autism without secondary symptoms as a CGI-S of 3, mildly ill. The communication problems, compromising use of the patient as an informant, were addressed by several strategies, including careful questioning of care providers, rating scales, laboratory tests, and physical exams. The broad subject heterogeneity requires outcome measures sensitive to individual change over a wide spectrum of treatment response and side effects. The problems of neuropsychologically testing nonverbal, lower functioning, sometimes noncompliant subjects requires careful instrument selection/adaptation and flexible administration techniques. The problems of assessing low-end IQs, neglected by most standardized test developers, was resolved by an algorithm of test hierarchy. Scarcity of other autism-adapted cognitive and neuropsychological tests and lack of standardization required development of a new, specially adapted battery. Reliability on the Autism Diagnostic Interview (currently the most valid diagnostic instrument) and other clinician instruments required extensive cross-site training (in-person, videotape, and teleconference sessions). Definition of a treatment responder required focus on individually relevant target symptoms, synthesis of possible modest improvements in many domains, and acceptance of attainable though imperfect goals. The assessment strategy developed is implemented in a RCT of risperidone (McDougle et al., 2000) for which the design and other methodological challenges are described elsewhere (Scahill et al., 2000). Some of these problems and solutions are partially shared with RCTs of other treatments and other disorders.

Mood stabilizers in the treatment of juvenile bipolar disorder. Advances and controversies

Controlled studies of mood stabilizer (mono and combination) therapy are needed in children and adolescents to develop safe and effective treatment strategies for a disorder that now has a cohort and that carries a high human and economic cost. Through the use of a variety of diagnostic instruments and novel outcome measures, we may continue to refine DSM categories into more sensitive and specific diagnostic constructs. In addition, identification of neurobiologic and genetic markers for early-onset BPD, ADHD, CD, and IED could provide powerful tools in the process of breaking down phenotypes and establishing biologic predictors of targeted pharmacologic interventions in the face of new drug developments.

Research Units on Pediatric Psychopharmacology (RUPP) Autism Network. Background and rationale for an initial controlled study of risperidone

This article has reviewed the background and rationale for the choice of risperidone as the first drug to be studied by the RUPP Autism Network. Risperidone has potent effects on 5-HT and DA neuronal systems, both of which have been implicated in the pathophysiology of autism. Unlike the typical antipsychotics, haloperidol and pimozide, which have been shown to be effective for reducing many of the maladaptive behaviors associated with autism, risperidone's 5-HT2A/DA D2 ratio of receptor blockade appears to produce a lower risk of acute and chronic extrapyramidal side effects, as well as enhanced efficacy for the "negative" symptoms of autism. Indirect clinical and preclinical evidence supports the use of risperidone to treat impaired social behavior, interfering repetitive phenomena, and aggression, targets of pharmacotherapy for many patients with autism. Numerous published open-label trials in children and adolescents with autism and related PDDs and one double-blind, placebo-controlled study in adults suggest that risperidone has promise for the treatment of children and adolescents with autism. Because most of these studies have been short-term, open-label trials in small samples, however, a large-scale controlled study of risperidone in children and adolescents with autism is needed to confirm these results. Finally, because it is likely that children who demonstrate short-term benefit from risperidone will remain on the medication indefinitely, the longer-term effectiveness and safety of risperidone in this population also needs to be determined. The design of this study and the assessments used are described separately.

REM sleep in depression is influenced by ethnicity

The influence of ethnicity on the manifestation of EEG sleep changes in depression was studied in 95 patients (21 African-Americans [AA], 17 Asians [AS], 37 Caucasians [C] and 20 Hispanics [H]) with unipolar major depression. Subjects were studied twice for 2 consecutive nights. On the second night of each 2-night session, placebo or scopolamine (1.5 microg/kg, IM, at 23.00 h) was administered. On the baseline (placebo) night, sleep architecture, sleep continuity and rapid eye movement (REM) sleep variables were generally comparable among the groups. However, REM sleep was less in AA and AS subjects than in C and H subjects. Furthermore, the distribution of REM sleep over the course of the night in AA and AS subjects differed significantly from that in the C and H groups. Although scopolamine significantly affected sleep continuity and REM sleep measures, no significant differential effects of scopolamine were observed. Because many antidepressants suppress REM sleep, the differences in baseline REM sleep observed might be related to the greater sensitivity of some ethnic-minority depressed patients to pharmacotherapy.

Relationship between ethnicity and sleep patterns in normal controls: implications for psychopathology and treatment

The purpose of the study was to examine ethnic influences on sleep regulation. Seventy-three normal volunteers from four ethnic groups (17 African-Americans, 10 Asians, 30 Caucasians and 16 Hispanics) were studied for two consecutive nights with sleep polysomnography recordings in the laboratory. The subjects were in good physical and psychological health, and were asymptomatic with respect to sleep/wake complaints or sleep disorders. With the exception of minor differences, sleep continuity, sleep architecture and rapid eye movement (REM) sleep patterns were comparable among the four groups. African-Americans had evidence of more stages 1 and 2 and diminished stage 4 sleep, whereas the Hispanics had higher REM density. These preliminary findings suggest that sleep patterns are remarkably similar across cultures. There are, however, important cross-ethnic differences, specifically in the depth of sleep and in phasic REM measures. Because sleep disturbances are common symptoms of emotional disorders and since many psychoactive agents affect sleep, cross-ethnic differences in sleep patterns may have potential implications for the treatment and prevention of psychiatric disorders.

Prenatal stress is associated with depression-related electroencephalographic sleep changes in adult male rats: a preliminary report

1. Prenatal stress in rats has been shown to produce long-term behavioral, neuroendocrine and neurochemical changes. These changes may model aspects of human depressive illness. 2. In this pilot investigation, adult male offspring exposed to stress in utero and non-stressed controls were studied using 24-hour electroencephalographic sleep recordings. 3. Prenatally stressed animals demonstrated reduced latency to the onset of rapid eye movement (REM) sleep, prolongation of the first REM episode, and diminished slow-wave sleep. 4. Although preliminary, the observed changes parallel those seen in studies of human depression. These data further support the face validity of the prenatal stress model as a potential tool for future studies on the pathophysiology of depressive disorder.

Cerebellar vermis lobules VIII-X in autism

1. The aim was to investigate cerebellar vermis cross-sectional area in a group of high-functioning autistic children and normal control children. 2. Cerebellar vermis area measurements were completed on MRI scans from 8 autistic children (mean age 12.5 +/- 2.2, mean IQ 83.3 +/- 11.9) and 21 normal children (mean age 12.0 +/- 2.8, mean IQ 115 +/- 11). 3. The area of cerebellar vermis lobules VIII-X was significantly smaller in the autistic children than in the normal control subjects. ANCOVA demonstrated a confounding effect of IQ on these results. 4. Larger studies of autistic and normal subjects will be needed to assess the relationship between cerebellar abnormalities, autistic symptoms and IQ.

Brain N-acetyl aspartate concentrations measured by H MRS are reduced in adult male rats subjected to perinatal stress: preliminary observations and hypothetical implications for neurodevelopmental disorders

The present study was undertaken to determine if the concentration of brain N-acetyl-aspartate (NAA), a putative neuronal marker, is reduced in adult rats subjected to stress during the perinatal period. As the prenatal stressor, pregnant rats were subjected to restraint stress for one hour twice daily from days 14-21 of gestation; stressed offspring were reared by normal dams and studied as adults. As the postnatal stressor, normal pups were reared by prenatally 'stressed' dams and studied as adults. As compared to non-stressed controls (n=6), NAA concentrations were significantly reduced 21 and 25% in left frontal cortex from the prenatal (n=4) and postnatal (n=6) stress groups. respectively. The data suggest that in perinatally stressed adult offspring permanent neuronal damage or loss has occurred. While no direct causal associations between perinatal stress and the developmental of particular disorders can be inferred from these limited data, the effects of perinatal stress on subsequent brain neuropathology are reviewed. particularly in relation to NAA. For hypothesis-generating purposes, the possible relevance of stress and NAA to the neurodevelopmental hypothesis of schizophrenia is discussed in greater detail.

Sleep electroencephalographic abnormalities in adolescent depressives: effects of scopolamine

In contrast to sleep studies of adult depressives that have consistently demonstrated abnormalities of sleep continuity, slow-wave sleep, and REM sleep, existing studies of depressed children and adolescents have been conflicting. Furthermore, only one study has explored the cholinergic regulation of sleep in early-onset depressives. In the present study, the electroencephalographic sleep of 20 adolescent outpatients with major depressive episodes and 13 normal control adolescents was obtained on two separate 2-night sessions, 1 night incorporating challenge with scopolamine. Depressed adolescents showed increased baseline phasic REM sleep measures, increased arousals, a trend toward reduced slow-wave sleep, and a greater difference in the change of first REM period density on the scopolamine night versus placebo night compared to controls. These findings support the continuity of some sleep abnormalities of depression into adolescence, and suggest that adolescent depression may be associated with alterations of cholinergic neurotransmission in some patients.

Abnormal ACTH and prolactin responses to fenfluramine in rats exposed to single and multiple doses of MDMA

The present study examined the persistent functional consequences associated with exposure to single and multiple doses of (+/-) 3,4-methylenedioxymethamphetamine (MDMA) as reflected by the neuroendocrine responses to d,l-fenfluramine (FEN). Adult male rats were administered a single dose of MDMA (20 mg/kg, s.c.) and challenged 2 weeks later with saline or FEN (2, 4, 6 and 8 mg/kg, s.c.). The corticotropin (ACTH) response to FEN (6 and 8 mg/kg) was blunted and the prolactin response to FEN (4 and 6 mg/kg) was enhanced in MDMA pre-treated rats. The ACTH and prolactin responses to FEN (6 mg/kg, s.c.) were then evaluated 4, 8 and 12 months after exposure to single and multiple doses MDMA (20 mg/kg, s.c. and 20 mg/kg, s.c., bid, x 4 days, respectively). The ACTH response to FEN was significantly reduced at 4 and 8 months in both MDMA treatment groups, and at 12 months in the multiple dose group only. In contrast, the prolactin response to FEN was enhanced in both groups of MDMA treated rats at 4 months, but only in the multiple dose group at 8 months. By 12 months, the prolactin response to FEN had normalized. Following multiple doses of MDMA, 5-HT concentrations were reduced significantly in the frontal cortex at 4 and 12 months. The results indicate that exposure to single or multiple doses of MDMA can produce functional alterations which can persist for months, whereas the biochemical sequelae were less robust and shorter lived.

Differential response of rapid eye movement sleep to cholinergic blockade by scopolamine in currently depressed, remitted, and normal control subjects

The degree of cholinergic dysregulation of sleep in adult depression was evaluated using scopolamine. On separate sessions, placebo and scopolamine (4.5 micrograms/kg, IM) were administered to 14 patients with unipolar major depression, 16 recovered/remitted patients, and 18 normal controls. Scopolamine increased rapid eye movement (REM) latency (RL), reduced REM activity (RA), REM density (RD), and REM duration, and increased the percentage of stage 4 sleep in all groups. There was a differential effect of scopolamine on RL, RA, and REM duration for the first REM period, and on percentage of stage 4 sleep. Whereas a primary cholinergic hyperactivity could account for the RA and RD responses, the response profile for RL was more compatible with reduced aminergic tone as the proximal cause of the cholinergic hyperactivity. Whether the sleep abnormalities observed in remitted patients reflect an underlying vulnerability for development or recurrence of depression, and/or a scar, remains to be determined.

Reciprocal influences among adrenocortical activation, psychosocial processes, and the behavioral adjustment of clinic-referred children

The reciprocal effects among cognitive-behavioral, environmental, and biological influences on clinic-referred children's (N = 64; 34 boys; M age 12.71 years) short-term psychological and psychiatric adjustment were studied. At clinic intake and 6 months later, standardized measures of adjustment and control-related beliefs were assessed. Before and after conflict-oriented parent-child interaction tasks the children's saliva was sampled. Adrenocortical responses (i.e., increases in salivary cortisol) to the social conflict task predicted children's internalizing problem behaviors and anxiety disorders at follow-up. Consistently high adrenocortical reactivity at intake and follow-up was associated with deflated social competence over the 6-month period. Also, specific patterns of discontinuity in children's internalizing behavior problems predicted individual differences in their subsequent adrenocortical responsiveness. Specifically, rising behavior problem levels across time predicted higher and declining behavior problem levels predicted lower adrenocortical reactivity at follow-up. Findings are among the first to suggest links among internalizing behavior problems, adrenocortical responsiveness to social challenge, and clinic-referred children's short-term cognitive-behavioral and emotional adjustment.

Adrenal gland volume in major depression: relationship to basal and stimulated pituitary-adrenal cortical axis function

We measured adrenal gland volume and both baseline and stimulated pituitary and adrenal cortical hormones in 35 unmedicated, major depressives and 35 individually matched normal control subjects. Mean adrenal volume in the depressives was significantly larger, by about 38%, than the adrenal volume of their matched controls. Basal plasma adrenocorticotropic hormone (ACTH)1-39 was significantly lower, and basal plasma cortisol was significantly higher, in the patients. In contrast, basal plasma ACTH determined by radioimmunoassay (RIA) was not significantly different between the two groups. The ACTH response to ovine corticotropin-releasing hormone (oCRH), whether measured specifically as ACTH1-39 or by the less-specific RIA, was highly significantly lower in the depressives than in the controls. However, neither the cortisol response to oCRH nor its response to low-dose ACTH 1-24 differed significantly between groups. In both groups of subjects, correlations between adrenal gland volume and all the hormone measures were low, and none represented more than 4% shared variance. In the patients, adrenal volume did not correlate significantly with duration of the present episode, lifetime number of episodes, melancholic subtype, Hamilton Depression Scale total score, or the Hamilton suicidality item. However, adrenal volume was significantly positively related to the somatization factor of the Hamilton scale, which was almost totally accounted for by the specific items of somatic symptoms and somatic anxiety.

Catecholamines in attention-deficit hyperactivity disorder: current perspectives

OBJECTIVE

To provide an update on the "catecholamine hypothesis" of attention-deficit hyperactivity disorder (ADHD).

METHOD

Recent work examining the measurement of the norepinephrine, epinephrine, and dopamine systems in ADHD and normal subjects is reviewed and discussed in the context of recent neuroimaging and animal studies.

RESULTS

While data clearly indicate a role for all three of the above neurotransmitters in ADHD, a hypothesis suggesting "too much" or "too little" of a single neurotransmitter will no longer suffice. The central norepinephrine system may be dysregulated in ADHD, such that this system does not efficiently "prime" the cortical posterior attention system to external stimuli. Effective mental processing of information involves an anterior "executive" attention system which may depend on dopaminergic input. The peripheral epinephrine system may be a critical factor in the response of individuals with ADHD to stimulant medication.

CONCLUSION

A multistage hypothesis is presented which emphasizes the interaction of norepinephrine, epinephrine, and dopamine in modulation of attention and impulse control.

Prenatal stress prevents the desensitization of the corticosterone response to TFMPP by desmethylimipramine, but not by phenelzine, in adult male offspring

Gravid female rats were subjected to one hour of restraint stress twice daily or left undisturbed from days 14-21 of gestation. Adult 105-day old male non-stressed (NS) and stressed (S) offspring were treated once daily with saline, desipramine (DMI) (10 mg/kg, sc) or phenelzine (5.0 mg/kg, sc) for 14 days. Twenty-four hours after the last injection, animals were challenged with saline or 1-(m-trifluoromethylphenyl)piperazine (TFMPP) (5.0 mg/kg, sc), a serotonin1B/2C (5-HT1B/2C) agonist, and plasma prolactin and corticosterone concentrations were measured one hour later. As compared to acute saline administration, TFMPP significantly increased prolactin and corticosterone concentrations in all groups. In NS offspring, both DMI and phenelzine treatment augmented the prolactin response, but blunted the corticosterone response, to TFMPP. In S offspring, the prolactin response to TFMPP also was augmented by phenelzine or DMI treatment, whereas the corticosterone response to TFMPP was blunted during phenelzine treatment. However, DMI treatment was not able to desensitize the corticosterone response to TFMPP in the S rats. The results indicate the adaptive capacity of 5-HT systems to DMI administration was compromised in adult animals exposed to stress in utero.

Adrenal gland volume in major depression. Increase during the depressive episode and decrease with successful treatment

BACKGROUND

Hyperactivity of the pituitary-adrenocortical axis is the most prominent neuroendocrine abnormality in major depression. It is state-related, returning to normal with resolution of the depressive episode. Adrenal gland enlargement also has been reported in patients with major depression and has been hypothesized as an index of cumulative lifetime depression. However, whether or not adrenal enlargement decreases with successful treatment of depression has not yet been studied, to our knowledge. We, therefore, determined adrenal gland volume in patients with major depression before and after treatment and in matched normal controls, and compared adrenal size with functional indexes of pituitary-adrenocortical activity.

METHODS

Adrenal volumes were measured by magnetic resonance imaging in nine adult and two adolescent patients with major depression during their illness and during full remission when medication had been stopped for at least 1 month, and in nine adult and two adolescent normal control subjects individually matched to the patients. Basal, 4 to 7 PM plasma corticotropin 1-39 and cortisol levels, and corticotropin 1-39 and cortisol responses to administration of ovine corticorelin and lowdose cosyntropin also were measured.

RESULTS

Mean adrenal gland volume was significantly larger, by about 70% in the patients while depressed than after successful treatment, and it also was significantly larger, again by about 70%, than the mean adrenal gland volume of their matched controls. After treatment, the mean adrenal volume of the patients decreased and was no longer significantly different from that of their controls at baseline. The magnitude of the decrease was significantly positively correlated with the duration of the depressive episode. Basal, late-afternoon plasma corticotropin 1-39 levels were significantly lower in the patients while depressed than in their matched controls, but basal plasma cortisol levels did not differ significantly among the three groups, nor did the corticotropin 1-39 and cortisol responses to corticorelin or the cortisol response to cosyntropin. Correlations between adrenal gland volume and basal corticotropin and cortisol levels, and the corticotropin and cortisol responses to hormone challenge, were not consistently in the expected direction in any of the three groups of subjects.

CONCLUSIONS

Adrenal gland enlargement occurring during an episode of major depression appears to be state-dependent, in that it reverts to the normal size range during remission after treatment. It thus does not appear to be an index of cumulative lifetime depression. The lack of a discernible relationship between adrenal volume and pituitary-adrenocortical activity remains to be explained and might be related to noncorticotropin influences on the adrenal gland, including other tropic hormones and/or neural mechanisms.

Exposure to threshold doses of nicotine in utero: II. Neuroendocrine response to nicotine in adult male offspring

Groups of gravid female rats were injected subcutaneously with saline (SAL), a low-dose of nicotine (LN) (0.05 mg/kg, bid) or a high-dose of nicotine (HN) (3.0 mg/kg, bid) from day 4 to day 20 of gestation, or were left undisturbed. In adult 120-day-old male offspring, the ACTH and prolactin responses to acute nicotine challenge were evaluated. The experiment was performed on three separate occasions. Based upon dose-response and time-course studies with nicotine in normal animals, the neuroendocrine responses to nicotine (0.75 and 1.0 mg/kg, sc) were measured 7.5 min after nicotine administration, the peak response-time for both hormones. The ACTH response to acute nicotine administration was blunted significantly in the HN rats, but normal in the LN rats, for all three experiments. In two experiments, the prolactin response to acute nicotine administration was blunted significantly in the HN rats, but enhanced significantly in the LN offspring. The results indicate that prenatal nicotine administration can produce long-term neuroendocrine effects involving nicotinic-receptor coupled circuits, with long-term functional sequelae produced by dosages of nicotine considerably smaller than previously shown to be pharmacologically/toxicologically active.

Psychiatric consultation in severe and profound mental retardation

OBJECTIVE

This study was designed to examine the relationship between reason for referral and subsequent DSM-III-R diagnosis in institutionalized individuals with severe to profound mental retardation. A heavy emphasis was placed on articulating how diagnostic criteria are applied in this population.

METHOD

The study population consisted of 251 patients consecutively referred for initial psychiatric consultation from a large series of institutionalized patients with predominately severe to profound mental retardation. On the basis of the chief complaint, subjects could be grouped into six overlapping categories: self-injury, aggression, hyperactivity, agitation, medical questions, and miscellaneous behaviors. Psychiatric diagnoses were made according to DSM-III-R criteria on the basis of simultaneous clinical examination, staff interview, and medical review. Relevant medical conditions were noted.

RESULTS

The authors demonstrate, as have others, that it is possible to make psychiatric diagnoses in this population and that psychiatric disorder is common. The most frequent diagnoses were impulse control disorders, anxiety disorders, and mood disorders. Comorbid medical conditions, particularly seizure disorders, are also common.

CONCLUSIONS

These results are consistent with the reported experience of others and underscore the importance of psychiatric involvement in the multidisciplinary assessment and treatment of individuals with retardation.