BACKGROUND: Autism spectrum disorder (ASD) is increasingly recognized as a public health issue. Irritability and aggression (IA) often negatively affect the lives of people with ASD and their families. Although many medications have been tested for IA in ASDs in randomized controlled trials (RCTs), critical quantitative analyses of these trials are lacking in the literature. OBJECTIVES:To systematically review and quantitatively analyze the efficacy and safety of pharmacologic treatments for IA in youth with ASD.DATA SOURCES: Studies were identified from Medline, PsycINFO, Embase, and review articles. METHODS:Original articles on placebo-controlled RCTs of pharmacologic treatments of IA in youth age 2 to 17 years with ASD were included. Data items included study design, study goals, details of study participants, details of intervention, study results, statistical methods, side effects, and risks of bias. The primary study outcome measure was the effect size of reduction in the Aberrant Behavioral Checklist-Irritability (ABC-I) scores in the medication group, as compared with placebo, in RCTs using parallel groups design. RESULTS:Forty-six RCTs were identified. Compared with placebo, 3 compounds resulted in significant improvement in ABC-I at the end of treatment. Risperidone and aripiprazole were found to be the most effective, with the largest effect sizes. Sedation, extrapyramidal sides effects, and weight gain were assessed quantitatively. CONCLUSIONS:Although risperidone and aripiprazole have the strongest evidence in reducing ABC-I in youth with ASD, a few other compounds also showed significant efficacy with fewer potential side effects and adverse reactions in single studies.

Objectives:Dysbindin (DTNBP1) has been identified as a susceptibility gene for schizophrenia (SZ) through a positional approach. However, a variety of single nucleotide polymorphisms (SNPs) and haplotypes, in different parts of the gene, have been reported to be associated in different samples, and a precise molecular mechanism of disease remains to be defined. We have performed an association study with two well-characterized family samples not previously investigated at the DTNBP1 locus. Methods: We examined 646 subjects in 136 families with SZ, largely of European ancestry (EA), genotyping 26 SNPs in DTNBP1. Results: Three correlated markers (rs875462, rs760666, and rs7758659) at the 3′ region of DTNBP1 showed evidence for association to SZ (p = 0.004), observed in both the EA (p = 0.031) and the African American (AA) subset (p = 0.045) with the same over-transmitted allele. The most significant haplotype in our study was rs7758659-rs3213207 (global p = 0.0015), with rs3213207 being the most frequently reported associated marker in previous studies. A non-conservative missense variant (Pro272Ser) in the 3′ region of DTNBP1 that may impair DTNBP1 function was more common in SZ probands (8.2%) than in founders (5%) and in dbSNP (2.1%), but did not reach statistical significance. Conclusion: Our results provide evidence for an association of SZ with SNPs at the 3′ end of DTNBP1 in the samples studied.

Our failure to find an association between NRG1 and schizophrenia might reflect different linkage disequilibrium (LD) patterns found in different populations, disease allelic heterogeneity, clinical heterogeneity of schizophrenia, or inadequate statistical power deriving from moderate sample size. NRG1, if a true gene for schizophrenia, accounts for a small fraction of the disease in most populations. The confirmation of NRG1 as a schizophrenia susceptibility gene will require studies with a comprehensive set of markers and in larger samples. The possibility remains that reports of NRG1 association might reflect false positives.