We know there is a strong genetic component to bipolar disorder. The role played by one’s environment is less clear.
A study out of Canada that followed 4,000 families for 30 years sheds insight into how socio-economic factors influence the development of serious mental illness.
The study began with a group in their 30s and followed them into their 60s. These people lived in impoverished neighborhoods in Montreal and faced the grinding challenges and stressors of poverty.
Through Canada’s National Health Service complete health information for the subjects of the study, including mental health diagnoses, was acquired. With this baseline established, the researchers were then able to focus on the survey group’s children.
The children grew up with the with the dangers and lack of opportunity inherent in urban neighborhoods wracked by poverty. In these children the researchers observed the development of psychosis-spectrum mental illness like bipolar disorder and schizophrenia.
6% of the children followed into adulthood developed psychosis-spectrum mental illness. That’s more than double the rate found in the general population.
Clearly, genetic inheritance alone does not explain the rate at which people acquire bipolar disorder.
Environmental factors that range from the stress of living in a violent neighborhood to the poor nutrition found in low income households clearly influence the development of severe mental illness.
Throughout the study data was collected from all participants, so the researchers were able to develop an accurate picture of how social behavior merges with these risk factors to result in psychiatric diagnoses.
They found that the children who grew up and became very aggressive or very withdrawn were the most likely to later be diagnosed with a psychotic disorder.
This data gives us a tremendous opportunity to intervene in the lives of children who share these characteristics as well as a genetic propensity to mental illness and guide them through their most difficult periods with communication and coping skills that can reduce the number who develop bipolar disorder or schizophrenia.
It should be noted that the researchers from UC Davis and Concordia University had to go to Canada to undertake this study. The availability and consistency of healthcare for low income residents there made accurate data collection possible. In the United States, where healthcare is often unavailable to low income residents, the data doesn’t exist and the ability to follow outcomes for so many individuals for so many years is not even possible.
My book Resilience: Handling Anxiety in a Time of Crisis is available now.