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Abnormalities in the inflammatory system are linked to many brain-based disorders, including but not limited to, MDD and bipolar disorder (BD). The impetus to consider inflammation as potentially relevant to the pathoetiology of domain-based psychopathology (eg, anhedonia) and/or mental disorders, is provided by a confluence of factors.
Many individuals who receive conventional treatments for mood disorders do not achieve/sustain symptom remission. Patient reports also indicate that among those who experience “clinically relevant improvement,” significant deficiencies and dissatisfaction with treatment remain, particularly as it relates to experiences in positive mental health, vitality, resiliency, and premorbid levels of function.
Support for research on inflammation in psychiatry comes from advances in the characterization of neurobiological alterations in individuals with brain-based disorders. The ability to identify and characterize genomic variants in large data sets using Genome-Wide Association Studies, as well as a fuller understanding of the role of microRNA. Finally, the Research Domain Criteria initiative of the NIH, has brought the field to the attention of common dimensions/domains of psychopathology regardless of DSM category.
Evidence implicates inflammation as a fundamental neurobiological alteration, thus targeting this system may provide beneficial effect on illness trajectory. Preliminary evidence indicates that some anti-inflammatory treatments are not only generally effective in mitigating dimensional psychopathology measures, but may have additional benefits on comorbidity that differentially affects individuals with mood disorders (eg, obesity).1
Dr. McIntyre reports that he is on the Speakers Bureau for AstraZeneca, Bristol-Myers Squibb, Janssen-Ortho, Eli Lilly, Lundbeck, Pfizer, Shire, Otsuka, Purdue, Takeda, and Allergan; he has received research support/grants from Stanley Medical Research Institute, National Alliance for Research on Schizophrenia and Depression (NARSAD), and National Institutes of Mental Health. Dr. Rong reports no conflicts of interest concerning the subject matter of this article.
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