Predictors of a clinical high risk status among individuals with a family history of psychosis.

BACKGROUND: Risk for psychosis can be assessed on the basis of genetic risk, referred to in the literature as family high risk (FHR) or through the presence of clinical high risk symptoms (CHR). Recent studies have also shown that certain risk factors (i.e. trauma, cannabis, migration) may play a role in the development of psychosis, possibly in combination with one another and in particular in combination with a family history of psychosis. It is unknown which risk factors may play a role in the prediction of CHR status among individuals whom are already genetically vulnerable. This study compared FHR individuals who also met CHR criteria to FHR individuals who did not on various risk factors, psychopathology and functioning.
METHOD: Participants were 25 who met FHR and CHR criteria (FHR + CHR) as determined by Structured Interview for Prodromal Syndromes, 25 who met only FHR criteria (FHR-non-CHR), and 25 healthy controls. A binary logistic regression was performed to determine the best predictors of belonging to the FHR + CHR group.
RESULTS: FHR + CHR and FHR-non CHR were significantly different on measures of age first tried cannabis (F = 3.65, p < 0.05) and IQ (F = 3.32, p < 0.05). FHR groups also differed on self-reported anxiety (F=11.79, p < 0.001) and current scores of social (F = 19.74, p < 0.0001) and role (F = 17.71, p < 0.0001) functioning. The most significant predictor of belonging to the FHR + CHR group was an earlier age of cannabis use (OR = 0.44, p = 0.05).
CONCLUSION: These preliminary results are promising in determining potential risk factors for the development of psychosis in those who are at risk for psychosis on the basis of a family history.