During the past fifty years, psychiatric research has moved from an emphasis on the psychological aspects of mental disorders to a focus on their neurobiological underpinnings. The goal: to develop a more precise diagnostic and treatment strategy, in keeping with the advances in oncology and other branches of medicine. This search for parity with medicine had its roots in the 19th century, an era where the pioneers in psychiatry found themselves falling behind their counterparts, who were developing specific links between the bacterial etiology of infectious diseases and their treatment, links that could not be found in mental disorders.
The discovery of antipsychotics and antidepressants in the 1950s resulted in less harm, but their effects were neither specific or precise, and did not result in better efficacy.
Indeed, our treatments during the 19th and early 20th centuries were neither precise or specific, and were often harmful, including blood-letting, trepanation, organ removal, and lobotomies. The discovery of antipsychotics and antidepressants in the 1950s resulted in less harm, but their effects were neither specific or precise, and did not result in better efficacy. Sad, but true even in 2018.
The advances in human genetics and neuroimaging seemed to hold great promise for psychiatry. Nevertheless, more than 12,000 genetic studies of schizophrenia have failed to reveal any findings useful in the clinic. Even when one combines the putative risk loci into a polygenic risk score (PRS), they account for only 3-7% of the risk. At this point the PRS cannot be used for prediction or validation of a diagnosis. The results of neuroimaging have been similar. One review of 98 MRI studies of bipolar disorder found only non-specific changes, while another review of 80 MRI studies of psychoses found no diagnostic or prognostic biomarkers.
‘Scientific inequality’ and funding allocation
Despite the failures of neurobiology to provide clinically meaningful advances in diagnosis and treatment, psychiatry is supporting and participating in the development of the Human Brain Project, the US Brain Initiative, and the Precision Medicine Initiative―among others―that will require expenditures of over $10 billion, in order to map the brain connectome, map every brain cell, and advance big-data technologies.
A key component of these strategies is the move to a new research framework for psychiatry, the Research Diagnostic Criteria, or RDoC. The move away from the DSM is badly needed, given its lack of validity. The RDoC will focus on symptoms/behaviors across standard DSM diagnoses, with a focus on neural circuitry. The primary goal is the development of precision medications.
The rise of socioeconomic inequality
In the meantime, funding for clinical care and research has fallen, although many parts of the U.S.A. struggle to find beds for the mentally ill, and we struggle with the opioid epidemic and increasing rates of depression and suicide. In the decades following the 1970s, mortality rates and outcome in schizophrenia worsened, despite the flood of antipsychotics and other treatment modalities.
In the meantime, funding for clinical care and research has fallen, although many parts of the U.S.A. struggle to find beds for the mentally ill, and we struggle with the opioid epidemic and increasing rates of depression and suicide.
Perhaps one reason for this rather dismal picture is the rapid growth of socioeconomic inequality that began in the 1970s. Higher levels of income inequality are correlated with higher levels of suicide, depression, substance abuse, as well as other social ills. Indeed, migration alone carries a 250% increase in the risk for schizophrenia, considerably larger than the genetic risk, yet imaging and genetic studies often neglect the social status of their subjects.
Unfortunately, the outlook for the United States is one of worsening income inequality and a diminishing safety net, leading me to predict that the future of the mentally ill will worsen―despite the remarkable advances in genomics, connectomics, and data processing.
To find out more about this topic, read Dr Dean’s review article published in Philosophy, Ethics, and Humanities in Medicine.