An Australian study suggests that children who are sexually abused, especially if it involves penetration, appear to be at higher risk for developing schizophrenia and other psychotic disorders, according to a report in the November issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

Previous studies have established that abused children are more likely to develop depression, anxiety, substance abuse, borderline personality disorders, posttraumatic stress disorder and suicidal behavior, according to background information in the article. "The possibility of a link between childhood sexual abuse and later psychotic disorders, however, remains unresolved despite the claims of some that a causal link has been established to schizophrenia," the authors write.

Margaret C. Cutajar, D.Psych., M.A.P.S., of Monash University, Victoria, Australia, and colleagues linked data from police and medical examinations of sexual abuse cases to a statewide register of psychiatric cases. Rates of psychiatric disorders among 2,759 individuals who had been sexually abused when younger than age 16 were compared with those among 4,938 individuals in a comparison group drawn from electoral records.

Over a 30-year period, individuals who had experienced childhood sexual abuse had significantly higher rates than those in the comparison group of psychosis overall (2.8 percent vs. 1.4 percent) and schizophrenia disorders (1.9 percent vs. 0.7 percent). Participants experienced abuse at an average age of 10.2, and 1,732 (63 percent) of cases involved penetration of a bodily orifice by a penis, finger or other object. Those exposed to this type of abuse had higher rates of psychosis (3.4 percent) and schizophrenia (2.4 percent).

"The risks of subsequently developing a schizophrenic syndrome were greatest in victims subjected to penetrative abuse in the peripubertal and postpubertal years from 12 to 16 years and among those abused by more than one perpetrator," the authors write. "Children raped in early adolescence by more than one perpetrator had a risk of developing psychotic syndromes 15 times greater than for the general population."

The results establish childhood sexual abuse as a risk factor for psychotic illness, but do not necessarily translate into abuse causing or increasing the risk of developing such a disease, the authors note. Many cases of childhood sexual abuse never come to light, and the overall population of abused children maybe significantly different from those whose abuse is detected by officials.

"Establishing that severe childhood sexual abuse is a risk factor for schizophrenia does have important clinical implications irrespective of questions of causality and irrespective of whether those whose abuse is revealed are typical," the authors conclude. "Children who come to attention following childhood sexual abuse involving penetration, particularly in the peripubertal and postpubertal period, should receive ongoing clinical and social support in the knowledge that they are at greater risk of developing a psychotic illness."

"Such treatment in our opinion should focus on improving their current functioning and adaptation to the demands of the transition from adolescent to adult roles rather than primarily on the abuse experience itself. Such an approach should benefit all victims, irrespective of whether they have the potential to develop a psychotic illness."

Dr. Cutajar received an Australian Postgraduate Award scholarship.