Shared and unique deficits of social functioning in multiple affected families with major psychiatric illness

BackgroundMental illnesses often cluster in families, and their impact on affected and unaffected members within families need to be understood from a social perspective. MethodsData was derived from 202 families with multiple affected individuals, identified under Accelerator program for Discovery in Brain disorders using Stem cells (ADBS) study. Affected individuals (N=259) had a diagnosis of schizophrenia, bipolar disorder, obsessive-compulsive disorder or substance use disorder. For comparison, we used the unaffected siblings from the same families (N=229), and a matched random subset of healthy control (HC) data (N=229) from the National Mental Health Survey (NMHS). We compared educational attainment, functional marital status and occupational status between the groups. ResultsThe groups were matched across age, gender and place of residence. The highest educational attainment was significantly different between the groups. The affected (9.9 years) and unaffected siblings (10.4 years) had poor educational attainment compared to HC (11.6 years), (F=8.97, p<0.001). Similarly, the affected (43%) and unaffected siblings (33%) remained more often single, in contrast to HC (23%), ({chi}2=40.98.17, p<0.001). However, employment rates were significantly higher in the unaffected siblings, especially female siblings. Females had overall lesser educational attainment, were largely married, and were majority homemakers across the three groups when compared to males. DiscussionOur study findings reveal the socio-demographic characteristics of affected and unaffected siblings from multiple affected families with major psychiatric illness in India. Affected and unaffected siblings had lower educational attainment and rates of marriage when compared to HC. The unaffected siblings were more likely to be in employment compared to HC. Whether the poor educational attainment and lower marriage rates in unaffected siblings is a biological marker of shared endophenotype or the effect of social burden of having an affected family member requires further systematic evaluation.