A combination of factors—not your fault.

There is no single cause of schizoaffective disorder. Most researchers agree it’s a complex mix of biology, environment, and experience. Understanding the possible causes won’t fix the illness—but it can reduce shame and help you make sense of what happened.

🔬 Biological Factors

  • Genetics: SZA tends to run in families. If a parent or sibling has a related disorder, your risk is higher. But genes are only part of the story.

  • Brain structure and chemistry: Imaging studies show changes in brain regions related to emotion, thinking, and perception. Many people with SZA also have irregularities in dopamine and serotonin signaling.

😔 Trauma and Stress

  • Childhood trauma, abuse, and neglect are strongly linked to the development of psychosis-spectrum disorders.

  • Chronic stress, especially without support, can contribute to symptom onset.

  • Life instability, marginalization, and oppression can all act as environmental risk factors.

☠️ Substance Use

  • Substances like cannabis, amphetamines, hallucinogens, and alcohol can trigger symptoms in vulnerable people.

  • In some cases, drug use reveals an underlying condition that might have otherwise remained dormant.

  • In others, it contributes directly to psychosis or mania.

Substance use doesn’t mean you “caused your illness.” It just complicates it—and makes treatment more difficult if it’s ongoing.

🔄 It’s Usually a Combination

Most people with SZA have more than one contributing factor: genetics, trauma, stress, substances, and life events all overlapping. It’s rarely simple, and it’s never your fault.