Comparative study of clinical and neuropsychological characteristics between early-, late and very-late-onset schizophrenia-spectrum disorders.

OBJECTIVE: To compare the clinical and neurocognitive profile of early-onset (EOP, <40 years), late-onset (LOP, 40-59 years) and very-late-onset (VLOP, ≥60 years) psychosis. DESIGN: Cross-sectional observational study. SETTING: Secondary, tertiary, and community mental health care. PARTICIPANTS: Patients with a DSM-IV diagnosis of non-affective psychotic disorder were included from two complementary studies (GROUP and PSITE) on genetic and environmental risk factors of psychosis in the Netherlands and Belgium. MEASUREMENTS: Main outcome measures were the severity of positive and negative symptoms, quality of life, and age-corrected scores on measures of general intelligence, verbal memory, attention, and executive function. One-year follow-up data were used to validate diagnoses and exclude participants with possible or probable dementia. RESULTS: 286 EOP (85%), 24 LOP (7%) and 28 VLOP (8%) participated. VLOP patients reported significantly more positive symptoms than EOP patients. Age-at-onset groups had similar age-corrected scores on IQ, verbal memory, attention and executive functions. A significantly better performance was found in VLOP compared with LOP on the CAMCOG total score, though scores were still within the normal range. After controlling for possible confounding, however, VLOP differed significantly on an attention accuracy task compared with LOP patients. Re-entering data for probable dementia patients (N = 4) did change the results regarding cognition outcomes. CONCLUSIONS: VLOP patients show more positive symptoms but do not appear to differ on neuropsychological tests from EOP and LOP when age is controlled for. This questions the idea that VLOP is the expression of underlying neurodegeneration.

Evidence that the impact of hearing impairment on psychosis risk is moderated by the level of complexity of the social environment.

BACKGROUND: It has been suggested that part of the increased vulnerability for psychosis in individuals with hearing impairment (HI) is the consequence of a decreased ability to form correct representations of the social world and attributions of intention of others. It was therefore hypothesized that associations between HI and psychosis risk would be sensitive to contextual variables representing higher level of social complexity, conceptualized as the population density of the social environment ('urbanicity'). METHODS: Urbanicity and objective HI were assessed in the Maastricht Aging Study (MAAS), a longitudinal study of 1,823 participants from the general population in Maastricht, the Netherlands. Participants were tested at baseline (T0) and at 6-year (T2) and 12-year follow-up (T4). The degree to which the association between HI (T0-T2) and psychotic experiences at T4 was moderated by T0 urbanicity was examined. RESULTS: The association between HI and psychosis was conditional on level of urbanicity (interaction chi2=7.51, p=.006), with low effect size in non-urbanized areas (b=-0.81, 95% CI:-2.98, 1.36) and high effect size in the most urbanized areas (b=2.56, 95% CI: 0.47, 4.65). Although social isolation (b=1.74, p=.022) and loneliness (b=0.61, pb.001) were both associated with psychosis, they could not explain the observed interaction. CONCLUSION: The findings suggest that level of complexity of the social world, in interaction with the individual's ability to correctly process this information, may impact on risk for psychotic experiences.

Evidence that better outcome of psychosis in women is reversed with increasing age of onset: a population-based 5-year follow-up study.

BACKGROUND: Female gender and later onset of psychosis are both associated with better outcome. However whether their effects are independent, is not known. METHOD: In 379 incident cases of psychoses, from an epidemiologically defined catchment area, admixture analysis was employed to generate age of onset classes. Five year course and outcome measured across clinical and social domains were used as dependent variables in regression analyses, to estimate associations of outcomes with gender, age of onset and gender by age of onset interaction. RESULTS: Three age of onset classes were identified: early (14-41 years), late (42-64 years) and very late onset psychosis (65-94 years). Overall, women had better outcomes, including milder delusions, fewer negative symptoms, less deterioration from baseline functioning, fewer hospital readmissions and shorter psychotic episodes. Later age of onset was also associated with better outcome, although in the very late onset class the results were mixed. There was a statistically significant gender by age of onset interaction (in the ratio scale) within this sample with men displaying poorer outcome in the early/late onset class, whereas women tended to have a worse outcome in the very late onset class. CONCLUSIONS: The favourable outcome in women becomes reversed in old age, suggesting gender-age-related differences in the distribution of aetiological factors for psychosis.

Mild hearing impairment and psychotic experiences in a normal aging population.

BACKGROUND: Hearing impairment (HI) in the elderly may be a risk factor for psychosis, but associations between HI and psychotic disorder or psychotic experiences have been reported more consistently in younger than in older populations. The aims of this study were to replicate the positive association between hearing impairment and psychotic experiences and to clarify any differences between groups of young and old individuals in a non-clinical, normal aging general population sample. METHODS: HI, assessed at baseline and at 3-year follow-up, and psychotic experiences, assessed at 3-year follow-up, were analysed in a group of 848 individuals aged 33 to 89 years between 1999 and 2004. HI was determined on the basis of both self-report and audiometric examination. The "psychoticism" and "paranoid ideation" subscales from the SCL-90-R were used to assess level of psychotic experiences. RESULTS: Self-reported hearing problems expressed as conversational HI (beta=0.080, 95% CI: 0.23, 7.90, p=0.038) and subjective HI (beta=0.087, 95%CI: 0.70, 10.30, p=0.025), but not audiometric objective HI, were associated with psychotic experiences. In those with hearing aids, associations with psychotic experiences were only present if accompanied by self-reported hearing problems that persisted in spite of the hearing aid. In addition, HI increased the risk for psychotic experiences specifically in younger rather than older individuals. CONCLUSIONS: Self-reported hearing problems rather than audiometric or remediated hearing loss may contribute to the development of psychotic experiences in younger rather than in older individuals.