Admixture analysis of age at onset in older patients with schizophrenia spectrum disorders.

The nature of schizophrenia spectrum disorders with an onset in middle or late adulthood remains controversial. The aim of our study was to determine in patients aged 60 and older if clinically relevant subtypes based on age at onset can be distinguished, using admixture analysis, a data-driven technique. We conducted a cross-sectional study in 94 patients aged 60 and older with a diagnosis of schizophrenia or schizoaffective disorder. Admixture analysis was used to determine if the distribution of age at onset in this cohort was consistent with one or more populations of origin and to determine cut-offs for age at onset groups, if more than one population could be identified. Results showed that admixture analysis based on age at onset demonstrated only one normally distributed population. Our results suggest that in older schizophrenia patients, early- and late-onset ages form a continuum.

Salivary Testosterone Is Consistently and Positively Associated with Extraversion: Results from The Netherlands Study of Depression and Anxiety.

BACKGROUND: Testosterone has been postulated as a 'social' hormone, but the relationship between testosterone and personality traits linked with socially oriented behaviors such as extraversion remains unclear. The objective of our study was to investigate the association between baseline salivary testosterone levels and the Big Five personality traits. METHODS: We studied the relationship between salivary testosterone (morning and evening) and NEO-FFI (Five-Factor Inventory) personality traits in 1,611 participants with lifetime or current depression and/or anxiety and 482 participants without depression/anxiety of the Netherlands Study of Depression and Anxiety (NESDA). RESULTS: The personality domain of extraversion was independently associated with higher salivary testosterone, both in healthy subjects (ß = 0.094; p = 0.04) and in subjects with lifetime or current depression and/or anxiety (ß = 0.092; p < 0.001). In multivariable adjusted analyses, extraversion remained the only personality trait that was positively associated with salivary testosterone (ß = 0.079; p = 0.006). CONCLUSION: We conclude that salivary testosterone is consistently and positively related to extraversion, supporting the notion of a hormonal basis of this personality trait, which may be linked to the tendency to strive for and maintain social status. © 2015 S. Karger AG, Basel.

Schizophrenia spectrum disorders in later life: prevalence and distribution of age at onset and sex in a dutch catchment area.

OBJECTIVES: The prevalence of schizophrenia in later life is affected by both outflow of early onset patients, due to recovery and excess mortality, and inflow of patients with a later age at onset, making it likely that characteristics of older patients differ markedly from younger patients. We assessed the prevalence of schizophrenia and spectrum disorders and their distribution according to age at onset and sex in an elderly population. DESIGN: Case register study. SETTING AND PARTICIPANTS: All patients age 60 years and older, in contact with the Mental Health Organization in a psychiatric catchment area in Amsterdam (the Netherlands), diagnosed with schizophrenia, schizoaffective disorder, or delusional disorder. MEASUREMENTS: One-year prevalence estimates, including rates according to age group, age at onset, and sex. In addition, we determined the effect of using different criteria for age at onset. RESULTS: The one-year prevalence of all disorders was 0.71%, subdivided in 0.55% for schizophrenia, 0.14% for schizoaffective disorder, and 0.03% for delusional disorder. The one-year prevalence of early-onset schizophrenia was 0.35%, of late-onset schizophrenia 0.14%, and of very-late-onset schizophrenia-like psychosis 0.05%. Variation of onset criterion affected the proportion of early-onset versus late-onset schizophrenia patients stronger in women than in men. Women outnumbered men markedly in the prevalence estimates for most diagnostic subgroups, including early-onset schizophrenia. CONCLUSIONS: We found the prevalence of schizophrenia among older persons to be well within the range reported for younger populations. The considerable proportion with a later age at onset and the strong female preponderance are distinguishing characteristics of older patients with clinical implications.