This is a map of repetition among all symptoms in the DSM-5.
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These findings are from a descriptive study published in Psychological Medicine which mapped the repetition among the 1419 symptoms described in 202 diagnoses of adult psychopathology in section II of the DSM-5. 2/10 cambridge.org/core/journals/…
The first stage of coding aimed to distil the constituent symptoms of the diagnoses in chapters 1–19 of section II of the DSM-5. The resulting list of symptoms was then coded for content overlap using both qualitative content coding and natural language processing. 3/10
In total, 202 diagnoses were represented, including 135 primary disorders and 76 specifiers or other specified disorders with additional symptoms. While repetition appeared to be pervasive, the majority (63.2%) of the 628 distinct symptoms were unique to a single diagnosis. 4/10
Overall, of the 202 diagnoses represented, 140 (69.3%) had at least one symptom that repeated in another diagnosis – 118 (58.4%) in a diagnosis in another chapter. 5/10
A noteworthy finding was that the symptoms in the DSM-5 that repeat most frequently, and that repeat across most chapters, are dominated by symptoms of major depressive disorder (MDD). 6/10
Specifically, 10 of the top 15 most non-specific symptoms in the DSM-5 appeared in the diagnostic criteria for MDD. 7/10
Perhaps MDD symptoms are psychological responses to stress, similar to how fever – a symptom that also cuts across numerous diagnostic categories – reflects an inflammatory response to cell damage or stress. 8/10
The pervasiveness of MDD symptoms throughout the DSM-5 likely hampers diagnostic accuracy through misattribution of symptoms in other diagnoses to MDD, and inflation of the rates of comorbidity due to symptom overlap with other diagnoses. 9/10
Ultimately, more empirical work on fine-grained clinical phenomena promises to improve on the reliability and validity of the DSM-5 constructs that frame much research and practice. 10/10
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There is a high degree of genetic correlation across psychiatric disorders - it’s time to refine the DSM.
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These findings are from a study in @ScienceMagazine which used genome-wide association data for 265,218 patients and 784,643 control participants to quantify the degree of overlap for genetic risk factors of 25 common brain disorders. 2/12 science.org/doi/abs/10.112…
Over the past century, the classification of brain disorders has evolved to reflect the medical and scientific communities’ assessments of the presumed root causes of clinical phenomena such as behavioral change, loss of motor function, or alterations of consciousness. 3/12
These findings are from a review in @ElsevierConnect which investigated the phenomenological overlap between autism and schizophrenia. 2/10 sciencedirect.com/science/articl…
Assuming no relationship between the disorders, if autism occurs in 1% of the population, and schizophrenia in a similar number, the frequency of an individual having both disorders would be one hundredth of a percent, or quite rare. 3/10
Coffee preserves the main biological mechanisms of aging.
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These findings are from a review in @ElsevierConnect which explored evidence from studies in humans supporting an ability of coffee and of its main components (caffeine and chlorogenic acids) to preserve the main biological aging mechanisms. 2/9 sciencedirect.com/science/articl…
The conception of coffee consumption has undergone a profound modification, evolving from a noxious habit into a safe lifestyle actually preserving human health. 3/9
There is an inverse, stepwise association between dietary creatine intake and depression.
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These findings are from a study in @transl_psych which examined the association between dietary creatine and depression in U.S. adults. 2/10 nature.com/articles/s4139…
Creatine, a nitrogenous organic acid endogenous to all vertebrates, plays a critical role in brain bioenergetics and is another promising nutraceutical candidate for depression. 3/10
Psilocybin decreases cerebral blood flow to the amygdala - a brain area that controls fear.
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These findings are from a study in @SciReports which used functional magnetic resonance imaging (fMRI) before and after treatment with psilocybin for treatment-resistant depression. 2/9 nature.com/articles/s4159…
Psilocybin with psychological support is showing promise as a treatment model in psychiatry but its therapeutic mechanisms are poorly understood. 3/9