Age of onset of cannabis use is associated with age of onset of high-risk symptoms for psychosis.

OBJECTIVE: Increasing interest in the prodromal stage of schizophrenia over the past decade led us to perform our study to monitor people at high risk for developing a psychosis. We hypothesized that cannabis use or a cannabis use disorder at a younger age relates to high-risk symptoms at a younger age. METHOD: People referred to the Academic Medical Centre in Amsterdam, the Netherlands, with an ultra-high risk (UHR) for psychosis were interviewed with the Composite International Diagnostic Interview to assess their cannabis consumption. The Interview for the Retrospective Assessment of the Onset of Schizophrenia was used to collect data about age of onset of high-risk or prodromal symptoms. Nine high-risk symptoms were selected and clustered because of their known relation with cannabis use. RESULTS: Among the 68 included participants, 35 had used cannabis (51.5%), of whom 15 had used recently. Twenty-two participants had been cannabis abusers or cannabis-dependent (32.4%) in the past. Younger age at onset of cannabis use was related to younger age of onset of the cluster of symptoms (rho = 0.48, P = 0.003) and also to 6 symptoms individually (rho = 0.47 to 0.90, P < 0.001 to 0.04). Younger age at onset of a cannabis use disorder was related to younger age of onset of the cluster of symptoms (rho = 0.67, P = 0.001) and also to 6 symptoms individually (rho = 0.50 to 0.93, P = 0.007 to 0.03). CONCLUSION: Cannabis use or a cannabis use disorder at a younger age in a group with an UHR for transition to psychosis is related to onset of high-risk symptoms for psychosis at a younger age.

Baseline differences in clinical symptomatology between ultra high risk subjects with and without a transition to psychosis.

BACKGROUND: The chance of transition to psychosis in patients at Ultra High Risk for developing psychosis (UHR) is 10-15%. The aim of present study was to investigate differences in baseline clinical symptomatology, general level of functioning (GAF-score) and genetic risk between UHR patients who did (UHR+T) or did not (UHR+NT) make a transition to psychosis. Sharpening UHR inclusion criteria may aid in improving prediction of transition to psychosis. METHOD: The study sample was taken from 285 patients who were examined within the Dutch Prediction of Psychosis Study (DUPS) at the Academic Medical Center of the University of Amsterdam, the Netherlands. Out of 73 included UHR subjects, 18 made a transition to psychosis. Psychopathology was investigated with the Structured Interview for Prodromal Syndromes, Bonn Scale for the Assessment of Basic Symptoms and GAF-score. The follow-up period of the study was three years. RESULTS: The UHR+T group showed more social anhedonia and withdrawal, more bizarre thinking and a lower GAF score at baseline than the UHR+NT group. CONCLUSIONS: In agreement with the results of Cannon et al. [Cannon, T.D., Cadenhead, K., Cornblatt, B., Woods, S.W., Addington, J., Walker, E., Seidman, L.J., Perkins, D., Tsuang, M., McGlashan, T., Heinssen, R., 2008. Prediction of Psychosis in Youth at High Clinical Risk: A Multisite Longitudinal Study in North America. Arch. Gen. Psychiat. 65 (1) 28-37.], our study indicates that severity of specific symptoms at baseline is related to transition to psychosis in UHR subjects. These findings may contribute to a more accurate prediction of a first psychotic episode. Furthermore, symptoms that are increased at baseline in the UHR+T group could be a focus of cognitive behavioural therapy in the UHR period.

Antisaccade task performance in patients at ultra high risk for developing psychosis.

Patients with schizophrenia consistently perform worse than healthy controls on the antisaccade task in which the subject is required to inhibit a reflexive saccade to a suddenly appearing visual target and look in the opposite direction. To our knowledge there is no research yet showing how patients at ultra high risk (UHR) for developing psychosis perform on the antisaccade task. The aim of the present study was to investigate antisaccade task performance in UHR patients. Patients were eligible for the study when they met criteria for one or more of the following groups: Attenuated symptoms or brief limited intermitted psychotic symptoms or a first-degree family member with a psychotic disorder and reduced functioning or basic symptoms. In 35 UHR patients we assessed antisaccades, neuropsychological test performance and symptomatology. Antisaccade task results were compared with those obtained in 42 age- and intelligence-matched patients with recent-onset schizophrenia and 28 matched healthy controls. Antisaccade error rate was significantly higher in the UHR patients than in the controls. Schizophrenia patients performed worse than the UHR patients and the control subjects. We found a trend towards higher antisaccade error rate at baseline in the UHR patients who later made the transition to psychosis compared to the UHR patients who did not make the transition to psychosis. Poor spatial working memory function was related to increased antisaccade errors in the UHR group. Abnormal antisaccade task performance is also present in patients at UHR for developing psychosis. Subsequent research needs to clarify if increased antisaccade error rate is predictive of a psychotic episode. In UHR patients, poor antisaccade performance may reflect working memory dysfunction.

Environmental factors and social adjustment as predictors of a first psychosis in subjects at ultra high risk.

BACKGROUND: The onset of schizophrenia is associated with genetic, symptomatic, social and environmental risk factors. The aim of the present study was to determine which environmental factors may contribute to a prediction of a first psychotic episode in subjects at Ultra High Risk (UHR) for developing psychosis. METHOD: We included 72 UHR subjects and followed them over a period of 36 months, of whom nineteen (26.4%) made a transition to psychosis. We applied survival analyses to determine associations between a transition to psychosis and environmental factors and social adjustment. To determine which items are the best predictors of transition to a first psychotic episode, Cox Regression analyses were applied. RESULTS: Urbanicity, receiving state benefits and poor premorbid adjustment (PMA) significantly influenced the transition to psychosis. Urbanicity (Wald=10.096, p=.001, HR=30.97), social-sexual aspects (Wald=8.795, p=.003, HR=1.91) and social-personal adjustment (Wald=10.794, p=.001, HR=4.26) appeared to be predictors for developing psychosis in our UHR group. CONCLUSIONS: Environmental characteristics and social adjustment are predictive of transition to a psychosis in subjects at UHR. These characteristics should be implemented in a model for prediction of psychosis. Such a model would be more specific than current models and may lead to patient-specific preventive interventions.

Diagnostic validity of the Eppendorf Schizophrenia Inventory (ESI): a self-report screen for ultrahigh risk and acute psychosis.

Providers of mental health services need tools to screen for acute psychosis and ultrahigh risk (UHR) for transition to psychosis in help-seeking individuals. In this study, the Eppendorf Schizophrenia Inventory (ESI) was examined as a screening tool and for its ability to correctly predict diagnostic group membership (e.g., help seeking, mild psychiatric complaints, highly symptomatic mood or anxiety disorder, UHR, acute psychosis). Diagnostic evaluation with established instruments was used for diagnosis in 3 research samples. UHR status was assessed with the Structured Interview for Prodromal Symptoms/Scale of Prodromal Symptoms (Miller et al., 1999) and the Bonn Scale for the Assessment of Basic Symptoms Prediction list (Gross, Huber, Klosterkötter, & Linz, 1987; Klosterkötter, Hellmich, Steinmeyer, & Schulze-Lutter, 2001). This study showed that members of different diagnostic groups rate themselves significantly differently on the ESI and its subscales. A new subscale was constructed, the UHR-Psychosis scale, that showed good utility in detecting individuals with interview-diagnosed UHR status and acute psychosis. The scale is also sensitive to the threshold between UHR and acute psychosis. Practical applications of the ESI include use as a diagnostic tool within various settings.