A recent study has revealed that close relatives of individuals with treatment-resistant depression (TRD) are at a significantly higher risk of developing depression that does not respond to traditional treatments. The study, conducted by senior author Dr. Cheng-Ta Li and his team at the National Yang Ming Chiao Tung University in Taipei, Taiwan, utilized an entire country’s data to confirm the genetic transmission of TRD across families and its association with other major psychiatric disorders.

According to the study, family members of individuals with TRD are not only nine times more likely to develop the same form of depression, but they are also at a higher risk of developing other psychiatric conditions such as anxiety, bipolar disorder, obsessive-compulsive disorder, major depressive disorder, and attention deficit hyperactivity disorder. Additionally, they are more likely to die by suicide.

Dr. Andrew McIntosh, a professor of psychiatry at the University of Edinburgh in Scotland, who was not involved in the study, emphasized that the findings provide convincing evidence that treatment-resistant depression tends to run in families. While the study suggests a genetic basis for TRD, it also acknowledges that family members may share common life events, socioeconomic disadvantages, or other unidentified risk factors.

The implications of these findings are significant as they shed light on the need for early treatment options for individuals at risk of treatment-resistant depression. The study advocates for early alternative treatments for this subgroup, as current antidepressants may not effectively address the different genetic and other causes of their depression.

Published in the journal JAMA Psychiatry, the study analyzed national health insurance data for the entire population of Taiwan over a 15-year period. The comprehensive data included inpatient and outpatient medical records as well as prescription information, providing valuable insights into the prevalence and impact of major depressive disorder in the country.

With over half a million Taiwanese receiving a diagnosis of major depressive disorder during the study period, and more than 21,000 of them identified as having treatment-resistant depression, the study underscores the importance of understanding the familial and genetic factors contributing to TRD. By recognizing the familial predisposition to treatment-resistant depression, experts believe that early intervention and tailored treatment approaches can be implemented to address the specific needs of individuals at risk.