Psychotic-like experiences in non-clinical subgroups with and without specific beliefs.

BACKGROUND: Assuming a transdiagnostic and extended psychosis phenotype, psychotic-like experiences (PLEs) and psychotic symptoms are on a phenomenological and temporal continuum between clinical and non-clinical populations. Recent research points towards differences in PLE proneness in different subgroups and clinical impact of different PLE subtypes. This study examines the prevalence of PLEs in three groups of individuals with and without specific sets of beliefs aiming to elucidate the question whether proneness to PLEs varies according to traditional versus less traditional supernatural beliefs. METHODS: The anonymized 16-item version of the Prodromal Questionnaire (PQ-16) was used to assess PLEs in three groups including individuals with religious beliefs (RB), belief in esoterism and paranormal phenomena (EB), and those embedded in scientific evidence approach and scepticism towards para-scientific theories (non-believers, NB). Male and female participants between 18 and 90 years were eligible for participation. RESULTS: The sample comprised 159 individuals including 41 RB individuals, 43 EB individuals, and 75 NB individuals. The mean PQ-16 score of the EB individuals (6.86 ± 4.13) was significantly higher compared to NB individuals (3.43 ± 2.99) and to RB individuals (3.38 ± 3.23) with almost twice the score (both p-values < 0.001). There was no significant difference between the PQ-16 scores of the NB group and the RB group (p = 0.935). No significant impact of age (p = 0.330) and gender (p = 0.061) was found on the PQ16-Score. Group affiliation to esoterism was associated with a higher PQ-16 score compared to group affiliation to religious beliefs (p < 0.001) and group affiliation to scepticism (p = 0.011), while the latter two did not differ significantly (p = 0.735). No significant difference was found between the three groups in the degree of distress related to the affirmatively answered PQ-16 items (p = 0.74). CONCLUSION: Under the assumption of a transdiagnostic psychosis phenotype, our findings provide more insight which subgroups within non-clinical samples have a higher likelihood of reporting PLEs.

Seasonality in schizophrenia-An analysis of a nationwide registry with 110,735 hospital admissions.

BACKGROUND: Seasonal patterns in hospitalizations have been observed in various psychiatric disorders, however, it is unclear whether they also exist in schizophrenia. Previous studies found mixed results and those reporting the presence of seasonality differ regarding the characteristics of these patterns. Further, they are inconclusive whether sex is an influencing factor. The aim of this study was therefore to examine if seasonal patterns in hospitalizations can be found in schizophrenia, with special regard to a possible influence of sex, by using a large national dataset. METHODS: Data on all hospital admissions within Austria due to schizophrenia (F20.0-F20.6) for the time period of 2003-2016 were included. Age standardized monthly variation of hospitalization for women and men was analyzed and the level of significance adjusted for multiple testing. RESULTS: The database comprised of 110,735 admissions (59.6% men). Significant seasonal variations were found in the total sample with hospitalization peaks in January and June and a trough in December (p < 0.0001). No significant difference in these patterns was found between women and men with schizophrenia (p < 0.0001). CONCLUSION: Our study shows that schizophrenia-related hospitalizations follow a seasonal pattern in both men and women. The distribution of peaks might be influenced by photoperiod changes which trigger worsening of symptoms and lead to exacerbations in schizophrenia. Further research is necessary to identify underlying factors influencing seasonal patterns and to assess whether a subgroup of patients with schizophrenia is especially vulnerable to the impact of seasonal variations.