It’s difficult to say exactly what causes mental health disorders. Much like a substance use disorder, genetics, environment, trauma, and early childhood exposure can determine whether you are diagnosed with a psychiatric disorder.
Your genetic makeup can be an essential factor for specific mental health diagnoses. In 2013, researchers at the University of North Carolina linked genetics to five major psychiatric disorders, schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorders, and attention-deficit/hyperactivity disorder.
Being raised in a stressful environment or having an abusive homelife are significant risk factors. Watching someone in your family struggle with mental illness, witnessing violence, or being subjected to violence in your environment all increases the odds that you may develop a mental health disorder. Other environmental influences that can occur at any time in your life can include financial stress, chronic medical conditions, deaths, or divorce.
It’s estimated that 80% of individuals diagnosed with Post-Traumatic Stress Disorder usually have at least one other diagnosis.
Early Exposure and Brain Development
Evidence suggests that exposure to some of the environmental concerns above at an early age can influence if you are likely to develop a co-occurring disorder. Exposure to drugs or alcohol in utero can play a significant role in mental health disorders.
None of these causes exist in isolation, and all likely influence each other. If you have a dual diagnosis, it’s difficult to say it’s due to genetics or environment. Most would agree that it’s likely that all of the above factors play a role.