Disruptive insights in psychiatry: transforming a clinical discipline

Abstract

Mental disorders such as schizophrenia, bipolar illness, and depression have become the predominant chronic diseases of young people, accounting for approximately 40% of the medical burden for people aged 15-44 in the United States and Canada. Research is transforming our understanding of these disorders, as exemplified in the articles in this Review Series. Important, "disruptive" insights into pathophysiology are emerging from studies addressing these illnesses as brain disorders, developmental disorders, and complex genetic disorders--rather than only as psychological conflicts or chemical imbalances, as they were considered in the past. Current medications are not sufficient for most patients. A new and deep understanding of the pathophysiology of these disabling disorders is our best hope for a new generation of treatments that will help patients to recover.

Figure 1. The development of cortical thickness in children with ADHD is markedly delayed in comparison with that in control children who are developing typically.

(A) Dorsal view of the cortical regions where peak thickness was attained at each age. The darker colors indicate regions where a peak age could not be calculated or the peak age was estimated to lie outside the age range covered. The sequence in which the regions attained peak thickness was similar in the two groups, but the children with ADHD showed considerable delay in reaching this developmental marker. (B) Kaplan-Meier curves illustrating the proportion of cortical points that had attained peak thickness at each age for all cerebral cortical points or the prefrontal cortex. The median age by which 50% of cortical points had attained their peak differed significantly between the groups (all P < 1.0 × 10^–20). Adapted with permission from Proceedings of the National Academy of Sciences (24).

Figure 2. Rethinking schizophrenia: identifying the illness before onset of psychosis.

In the future, schizophrenia may be viewed as a multistage disorder with psychosis analogous to myocardial infarction in ASHD. As in ASHD, early detection could introduce an era of preemptive treatments for schizophrenia, yielding better outcomes by halting the disease process before onset of psychosis. ASA, acetylsalicylic acid.

Figure 3. Estimated monozygotic (MZ) and dizygotic (DZ) twin concordance rates for various neuropsychiatric and other medical disorders.

Data from twin studies indicate that the heritabilities of mental disorders are higher those of many common disorders that have yielded significant findings in GWASs. MDD, major depression disorder. Compiled from refs. –.