Are socially shy and somewhat withdrawn people more susceptible to schizophrenia?

No: Social withdrawal can be a symptom of schizophrenia, but being shy and socially withdrawn does not increase the risk of developing schizophrenia. Shyness and social withdrawal can be symptoms of other disorders and should be evaluated by your physician or a psychiatrist.

Yes and not but.....: Being socially shy and withdrawn does not make one susceptible to schizophrenia per se. However, there are personality types that predispose one more to schizophrenia. These personality disorders (schizoid, paranoid) are associated with some social withdrawal and isolation in addition to other symtoms.

No: The socially shy and withdrawn behavior may be predromal symptoms of schizophrenia. This means they may be associated with the disease , schizophrenia, and appear before the psychotic symptoms present.