The effect of being left home alone at age 3 years on schizotypy and antisocial behavior at ages 17 and 23 years

Abstract Objective Negative home environments are associated with both schizophrenia-spectrum disorders and crime, but whether this is due to the social or cognitive sequelae of such environments is unclear. This study investigates the effect of early home environments on adult mental health. Method Using data from the Mauritius Child Health Project, a multiple time-point prospective study where all children born in 1969 in two towns (Quatre Bornes and Vacaos) were recruited at age 3 years ( N  = 1794), a group of children left home alone at age 3 ( n  = 34) were compared to children cared for by siblings/relatives ( n  = 222), or by mothers ( n  = 1498) on antisocial behavior and schizotypal personality at ages 11, 17, and 23 years. Results Home alone children showed higher scores on psychotic behavior and conduct disorder at age 17, and also schizotypal personality and crime at 23 years compared to the other groups. No negative behavioral or cognitive effects were observed at age 11. Findings were not accounted for by social adversity or ethnicity and appear to be ‘sleeper effects’ in that they do not emerge until later adolescence and into adulthood. Conclusions Findings appear to be the first to show the negative effects of dual-parental daytime absence on adult schizotypy and crime, a finding that cannot be accounted for by verbal and spatial cognitive impairments. Results suggest an early common psychosocial denominator to the two comorbid conditions of antisocial behavior and schizotypy.