Although social phobia and paranoia are considered to be separate conditions they do share similarities, both in terms of psychology and behaviour. Both groups of patients think that they are the object of other people's interest and that they are being judged by others. They scan their environment for socially-threatening information and both groups conclude that people are talking about them. A team of Dutch researchers looked into the links between the two conditions in a sample of 7,076 people. They were assessed for social phobia and paranoia at the start of the study, and one, and three years later. The study found that social phobia and paranoia were associated. People with paranoia were four times as likely to develop social phobia and the more paranoid people were the more social phobia symptoms they developed. However social phobia did not seem to lead on to people becoming paranoid.
Rietdijk, J. ... [et al] - Are social phobia and paranoia related, and which comes first? Psychosis February 2009, 1(1), 29-38