A study in JAMA by Danish researchers examined the correlation between household income during a child’s early years and the likelihood that they will develop schizophrenia later in life. In an editorial, Margaret T. Morris Professor of Health Care Policy Richard G. Frank, PhD, offered reflections on this study. 

Frank notes that the study, which offers evidence that low household income may be associated with a higher likelihood of developing schizophrenia, does not claim causality. Frank  notes that it is “important to recognize that the reason that these results are notable is because there is a suspicion that economic status affects the risk of illness” and suggests that causal pathways may be worth investigating. 

Current research suggests that heritability accounts for up to 85% of the risk of developing schizophrenia, but the importance of parental income and early childhood environment should not be ignored. Excessive or toxic stress in a child’s environment can interact with genes, affecting their brain development. The conduct and quality of care and education early in life can affect the damage caused by the stress. 

Low income levels are commonly associated with stressful environments such as substandard housing and neighborhoods that experience crime and violence. Low income parents are more likely to have inflexible work commitments and less money to spend on childcare, which can lead to lower quality of care for their children. 

Frank suggests that in order to better shape policies involving those living in poverty it is important to understand the links between income and mental illness. A family living in a low income environment with a child at high hereditary risk of developing schizophrenia may benefit from childcare, early education, and parenting support. More knowledge and research on this correlation can help support policies that will have a large effect on the health of the entire low income population.