[Risperidone use in child and adolescent psychiatric patients]

Association between second-generation antipsychotics and changes in body mass index in adolescents

PURPOSE

To assess the association of second-generation antipsychotics (SGAs) with changes in body mass index (BMI) among adolescents compared with a matched untreated comparison group.

METHODS

A retrospective cohort study was conducted using an electronic medical record database between January 2004 and July 2009. Adolescents (12-19 years old), newly initiated on SGAs formed the exposure group and untreated adolescents formed the comparison group matched (3:1) to the antipsychotic group based on age, gender, and month of index SGA. Both the exposure and comparison groups were followed for slightly more than a year (395 days). Baseline and follow-up BMI were evaluated for both groups and percentage change from baseline BMI to follow-up BMI was calculated. Multivariate linear regression was conducted to assess the impact of SGAs on percent change in follow-up BMI from baseline controlling for demographic characteristics, baseline medications, comorbidities, and other covariates.

RESULTS

The mean percentage increase in follow-up BMI from baseline for antipsychotic group was significantly higher than the comparison group (p < .01). After adjusting for covariates, adolescents on olanzapine had the highest percentage increase in follow-up BMI from baseline (5.84%, 95% confidence interval [CI], 4.07-7.61) followed by aripiprazole (4.36%; 95% CI, 3.08-5.64), risperidone (3.65%; 95% CI, 2.61-4.68), and quetiapine (1.53%; 95% CI, .53-2.52) compared with the comparison group.

CONCLUSION

This study further validates a growing concern of increased BMI in adolescents on SGA therapy.

[Aripiprazole use in children and adolescent psychiatric patients]

Aripiprazole inaugurates a new generation of antipsychotics called dopamine-serotonin system stabilizers. Its mechanism of action is different as aripiprazole is a partial dopamine D(2) and serotonin 5-HT(1A) receptor agonist and 5-HT(2A) receptor antagonist. Therefore, aripiprazole is thought to have an antagonistic action in the mesolimbic pathway but an agonistic action in the mesocortical pathway, tending to normalize the dopaminergic transmission regardless of the type of imbalance. Clinical trials involving children and adolescents have demonstrated the efficacy of aripiprazole in bipolar disorders, schizophrenia, mood disorders associated with pervasive developmental disorders, in tics and Tourette's. The most frequent side effects are extrapyramidal symptoms and sleepiness and are dose-dependent. Nevertheless, contrary to other second-generation antipsychotics available in France, it induces little weight gain, does not modify lipid and glucidic profiles, does not increase prolactin levels, or induce QTc lengthening. The main advantage of aripiprazole is its good safety profile, with different toxicity targets to other second-generation antipsychotics available in France. Aripiprazole appears to be an alternative for children and adolescents who are vulnerable to these side effects and are having trouble coping with them.

Mapping brain abnormalities in boys with autism

Children with autism spectrum disorder (ASD) exhibit characteristic cognitive and behavioral differences, but no systematic pattern of neuroanatomical differences has been consistently found. Recent neurodevelopmental models posit an abnormal early surge in subcortical white matter growth in at least some autistic children, perhaps normalizing by adulthood, but other studies report subcortical white matter deficits. To investigate the profile of these alterations in 3D, we mapped brain volumetric differences using a relatively new method, tensor-based morphometry. 3D T1-weighted brain MRIs of 24 male children with ASD (age: 9.5 years +/- 3.2 SD) and 26 age-matched healthy controls (age: 10.3 +/- 2.4 SD) were fluidly registered to match a common anatomical template. Autistic children had significantly enlarged frontal lobes (by 3.6% on the left and 5.1% on the right), and all other lobes of the brain were enlarged significantly, or at trend level. By analyzing the applied deformations statistically point-by-point, we detected significant gray matter volume deficits in bilateral parietal, left temporal and left occipital lobes (P = 0.038, corrected), trend-level cerebral white matter volume excesses, and volume deficits in the cerebellar vermis, adjacent to volume excesses in other cerebellar regions. This profile of excesses and deficits in adjacent regions may (1) indicate impaired neuronal connectivity, resulting from aberrant myelination and/or an inflammatory process, and (2) help to understand inconsistent findings of regional brain tissue excesses and deficits in autism.