Life Course Challenges Faced By Siblings of Adults With Schizophrenia Increase Risk for Depressive Symptoms
Background and Purpose: Although previous research has shown an increased risk for siblings of individuals with schizophrenia to develop depressive symptoms, few studies have investigated the impact of early life and current stressors in understanding this phenomenon. Therefore, this study examines the relationship between stressors of siblings and depressive symptomology. In comparing siblings of individuals with schizophrenia to a control group consisting of siblings of healthy control subjects, the study intended to identify whether early life and current stressors significantly predicted depressive symptoms in this population.
Sample: Participants were recruited through the Conte Center for the Neuroscience of Mental Disorders at Washington University in St. Louis (2006-2008) and included 23 siblings of healthy control subjects and 41 siblings of individuals with a DSM-IV diagnosis of schizophrenia. Participants in the current study were part of a larger study that included their brother or sister who was healthy or was diagnosed with schizophrenia. The Washington University in St. Louis Institutional Review Board approved this study.
Methods: Participants, group-matched for age, gender, race, and parental SES, completed a self-administered questionnaire measuring depressive symptoms, instrumental support provided to a sibling, devaluation of families coping with mental illness, and early life stressors affecting sibling development (i.e., parentification and barriers to social development). Participants also completed a neuropsychological test battery to assess cognitive functioning.
Results: Among siblings of individuals with schizophrenia, higher levels of depressive symptoms were associated with lower cognitive function (β= -.67, p<.001), stigma (β=.37, p<.01), and the perception that one’s brother or sister’s emerging illness had a greater impact on the sibling’s social life during childhood and adolescence (β=.39, p<.01). In this group, taking on adult responsibilities (i.e., parentificaton) while growing up was found to be protective against depressive symptoms in adulthood (β= -.36, p<.01).
Implications and Conclusions: After accounting for the influence of global cognitive impairment and gender, our findings suggest that childhood burden and societal stigma towards families coping with mental illness contribute unique variance to the measure of depressive symptoms experienced by siblings of individuals with schizophrenia. Our findings also indicate that a higher level of parentification in siblings of individuals with schizophrenia functioned as a protective factor against depressive symptoms. Future research is needed to understand the protective nature of parentification for siblings of individuals with schizophrenia. Current stressors, such as their perceived devaluation for having a relative with mental illness, predict that these siblings will have greater depressive symptoms. This finding reinforces the value of programs that address self-stigma in family members. Mental health service providers and psychoeducation programs would benefit by considering the identified psychosocial factors that are involved in the development of depressive symptoms for siblings of individuals with schizophrenia.