After the first hospitalization for schizophrenia, Salisbury et alArticle demonstrate progressive reductions in left temporal lobe cortical gray matter, including the primary auditory cortex, that are highly correlated with progressive functional impairment in the mismatch negativity brain wave, a neurophysiological/functional index of echoic memory. This worsening conjoint impairment suggests a progressive disease component and indicates the mismatch brain wave may be a useful biomarker for progression.
Using meta-analysis, Dickinson et alArticle compared the schizophrenia impairment on digit symbol coding tasks with impairments on 36 other cognitive measures. The digit symbol effect was significantly larger than effects for widely used measures of episodic memory, executive functioning, and working memory. This 5-minute task taps an information processing inefficiency that is a central feature of the schizophrenia cognitive deficit.
Merikangas et alArticle present the prevalence estimates of the bipolar spectrum in a probability sample of the United States. These findings provide evidence for the underlying dimensional nature of bipolar illness. Comorbidity with other disorders occurs in the majority of those with bipolar disorder. Use of mood stabilizers is uncommon, especially in general medical settings.
Naydenov et alArticle used gene expression microarrays to examine gene expression levels in lymphocytes from patients with bipolar disorder. They found that gene transcripts of proteins of the mitochondrial electron transport chain were lower when the cells were subjected to low-glucose stress, while in nonstressed cells, patients with bipolar disorder and control subjects were indistinguishable.
Compton et alArticle present the epidemiology of DSM-IV drug abuse and dependence in the United States. Current prevalences of drug abuse and dependence were 1.4% and 0.6%, respectively. Significant disability and comorbidity were particularly associated with drug dependence. Only 37.9% of those with drug dependence were ever treated.
In a prospective community sample of children and adolescents, Copeland et alArticle found that more than two thirds of children reported at least 1 potentially traumatic event by age 16 years, yet few meet the criteria for DSM-IV posttraumatic stress disorder. About 1 in 10 children displayed some posttraumatic stress symptoms in response to a potential trauma.
Using data from a high-risk community sample, Laucht et alArticle investigated whether gene × environment interactions may underlie the inconsistent findings regarding the association between the dopamine transporter gene (DAT1) and attention-deficit/hyperactivity disorder. They found evidence that environmental risks moderated the impact of the dopamine transporter gene on attention-deficit/hyperactivity disorder symptoms, suggesting a DAT1 effect only in those individuals exposed to psychosocial adversity.
When Barker et alArticle examined developmental trajectories of violence and theft and the neurocognitive performance of individuals following these trajectories, they found violence and theft were described by different trajectories, relating negatively to violence and positively to theft. Their results suggest that aggregating theft and violence may mask the developmental and causal mechanism of these behaviors.
Using data from a nationally representative survey, Bambauer et alArticle demonstrated that depressive symptoms were associated with cost-related nonadherence to prescription medications among elderly Medicare beneficiaries. Beneficiaries with disabilities and depressive symptoms were particularly vulnerable to being unable to adhere to medications because of cost. These findings suggest that providers should elicit information regarding economic barriers that might interfere with treatment of Medicare beneficiaries with depression.