After all, the most widely used scale of depression, the nine-item Patient Health Questionnaire (PHQ-9) asks patients, “Over the last 2 weeks, how often have you been bothered by any of the following problems?” The highest answer one can give is “Nearly every day.” Are we incorrect to think that if one were suicidal every minute of the past 2 weeks, one would still score, nearly every day, even if one’s symptoms were relieved for the past hour? Thus, a maximum score of 27 would remain a 27 no matter what happened in the past hour.
We do realize that we are being overly literal. Ketamine makes some people feel better quickly, and researchers try to capture that effect by asking patients about their symptoms within short intervals. Furthermore, one has to start somewhere. After the infusion is a reasonable time to ask patients how they feel. We are also cognizant that many ketamine researchers do more long-term follow-ups and/or have recommended longer-term studies. Nonetheless,
Expanding our definition of depression to encompass experiences with short time frames may have unintended consequences. As living circumstances rarely change in minutes, the emphasis on rapid recovery makes the patients more in control of their reported experiences and thus their diagnoses. One cannot assess a patient’s impairment or disability from minute to minute. One is left with emphasizing the patient’s subjective symptoms and deemphasizing their relationships, goals, and daily functioning. How could one measure eating habits, hygiene, or participation in hobbies every hour? Another consequence of this reduced time frame is the expansion of a diagnosis that no longer requires the presence of symptoms for 2 weeks. Considering the already vast number of people diagnosed with depression,9,10 this small change may further expand the number diagnosed with a mood disorder. Perhaps to many practitioners and patients these arguments seem obtuse and fastidious, but there is a core failure in modern psychiatry to clearly differentiate the human condition from mental illness. Said failure has vast implications for psychiatric epidemiology, the sociological understanding of psychic suffering and suicide, as well as the overprescribing of psychotropic medications.
Ketamine is an exciting prospect to many psychiatrists who feel like we have had little advancement and few novel treatments in a long time; advertised breakthroughs in the treatment of depression since fluoxetine have not been particularly impressive. Furthermore, the concerns about potential ketamine abuse are not theoretical but a very real problem in some parts of the world.11,12 The concerns about abuse are worsened considering recent evidence that suggests that ketamine’s effect may be driven by its opiate rather than NMDA effects.13 While some have discussed those concerns, we think that the field also needs to address the fact that the debate about ketamine is also changing our definition of depression.