The major diagnostic systems for mental illness, namely the Diagnostic and Statistical Manual of Mental Disorders (DSM) associated with the American Psychiatric Association and International Classification of Diseases (ICD) linked to the World Health Organization emphasize discrete conditions, such as Major Depression and Persistent Depressive Disorder in the case of depression, and Generalized Anxiety Disorder and Panic Disorder for anxiety. Currently there is DSM-5 and ICD-10. These discrete conditions sound very good and are appealing, but totally inaccurate! This issue is addressed in my book, Defining Mental Illness: Continuums, Regulation, and Defense. Nature tends to be organized dimensionally, with truly discrete entities the exception, likely derived from trait variation related to natural selection. Due to this reality I proposed the Continuum Principle: Natural phenomena tend to occur on a continuum, and any instance of hypothesized discreteness requires unassailable proof. Evidence for discrete mental illness conditions does not even come close to this standard. A continuous organization captures the true nature of these conditions. The illusion of discreteness can arise as an emergent property of increasing severity, as with melancholic depression representing the most extreme end of the depression continuum. In a similar fashion extreme anxiety involves the fight, flight, freeze response producing a panic attack. Triggering circumstances can also create this illusion, such as with winter stimuli intensifying behavioral inhibition and reducing behavioral activation triggering depression, instead of representing the discrete condition of Seasonal Affective Disorder (SAD)—In DSM-5 this condition has been shifted to depression with seasonal pattern. Likewise, social circumstances combined with personality issues such as introversion and low self-confidence can trigger social anxiety.
Reading this some will get it, while others will think that this does not feel right, the latter reaction highlighting how we prefer discrete conditions because this approach simplifies information processing. We think in terms of good and bad people, homosexual and heterosexual, instead of gradients. To a large extent the major diagnostic systems for mental illness derive from how we prefer to see things, a very unscientific occurrence. Then there is the dark side of how pharmaceutical companies can market products easier to discrete conditions than continuums. In 2010 antipsychotics and antidepressants were in the “Top 5” bestsellers generating $16.9 billion and $16.1 billion, respectively, in sales, aided by the sellout of academic psychiatry to big pharma! Essentially, psychiatry became a captured discipline beholden to the pharmaceutical industry. Now you might wonder how this process occurs? Academic psychiatrists dealing with medications, as opposed to psychotherapy, rely heavily on pharmaceutical companies for research funding. These psychiatrists ensure that they are on committees determining the criteria for supposed discrete diagnosis. Typically, 100% of those on the Mood Disorders and Psychotic Illnesses sub-committees have links to the pharmaceutical industry. Naturally they are going to support discrete conditions, and certainly when they align with our natural tendency to see discrete entities.
This problem of the pharmaceutical industry capturing psychiatry and ensuring discrete conditions arguably began with Dr. Donald Klein, who in 1964 proposed panic as a discrete condition. He was funded at the time by Geigy and Smith & Kline & French. Due largely to his influence on the DSM-III Anxiety and Dissociative Disorders sub-committee, Panic Disorder became a discrete condition in DSM-III (1980). Previously in DSM-II panic was seen as an extreme expression of anxiety, anxiety neurosis, “characterized by anxious over-concern extending to panic, and frequently associated with somatic symptoms.” In 1981 Upjohn marketed Xanax (alprazolam) for the new discrete condition of Panic Disorder, despite its own research showing little support for a separate condition. Insiders referred to the “condition” as the “Upjohn Illness.” Xanax was a blockbuster seller. 35 years later with DSM-5 the same problem is playing out, but interestingly big pharm appears to be distancing itself from psychiatry given that there are no new products that are working out, despite the inherent biases within the system. This outcome is not surprising when a discipline is captured and removed from real science focused on true outcomes!
