Twenty Years of Schizophrenia Research in the Northern Finland Birth Cohort 1966: A Systematic Review.

Birth cohort designs are useful in studying adult disease trajectories and outcomes, such as schizophrenia. We review the schizophrenia research performed in the Northern Finland Birth Cohort 1966 (NFBC 1966), which includes 10,934 individuals living in Finland at 16 years of age who have been monitored since each mother's mid-pregnancy. By the age of 44, 150 (1.4%) had developed schizophrenia. There are 77 original papers on schizophrenia published from the NFBC 1966. The early studies have found various risk factors for schizophrenia, especially related to pregnancy and perinatal phase. Psychiatric and somatic outcomes were heterogeneous, but relatively poor. Mortality in schizophrenia is high, especially due to suicides. Several early predictors of outcomes have also been found. Individuals with schizophrenia have alterations in brain morphometry and neurocognition, and our latest studies have found that the use of high lifetime doses of antipsychotics associated with these changes. The schizophrenia research in the NFBC 1966 has been especially active for 20 years, the prospective study design and long follow-up enabling several clinically and epidemiologically important findings. When compared to other birth cohorts, the research in the NFBC 1966 has offered also unique findings on course and outcome of schizophrenia.

Poor premorbid school performance, but not severity of illness, predicts cognitive decline in schizophrenia in midlife.

Neurocognitive dysfunction is common in schizophrenia but its course and determinants remain uncertain. Our aim was to analyse if premorbid school performance and the severity of illness and functioning predict change in cognition in schizophrenia in a general population sample. The sample included cases with schizophrenia spectrum disorder from the Northern Finland Birth Cohort 1966. Data on school marks at the age of 16 years, educational level at the age of 34 years, severity of symptoms and occupational functioning around first episode and after years of illness were gained from national registers, hospital notes and interviews. Change of verbal and visual learning and memory and executive functioning were examined between ages 34 and 43 years. The number of cases varied in analyses from 29 to 41, depending on missing data in particular cognitive tests. Lower school marks at age 16 years and lower education at age 34 years predicted more decline of cognition. Measures of severity of illness or functioning were not associated statistically significantly with change of cognition. Premorbid school performance, but not later course of schizophrenia, related to change of cognition in midlife. Poor premorbid scholastic performance and post-onset cognitive decline may represent related processes as part of an endophenotype of schizophrenia.

A systematic review and meta-analysis of recovery in schizophrenia.

OBJECTIVE: Our primary aims were (a) to identify the proportion of individuals with schizophrenia and related psychoses who met recovery criteria based on both clinical and social domains and (b) to examine if recovery was associated with factors such as gender, economic index of sites, and selected design features of the study. We also examined if the proportions who met our definition of recovery had changed over time. METHOD: A comprehensive search strategy was used to identify potential studies, and data were extracted for those that met inclusion criteria. The proportion who met our recovery criteria (improvements in both clinical and social domains and evidence that improvements in at least 1 of these 2 domains had persisted for at least 2 years) was extracted from each study. Meta-regression techniques were used to explore the association between the recovery proportions and the selected variables. RESULTS: We identified 50 studies with data suitable for inclusion. The median proportion (25%-75% quantiles) who met our recovery criteria was 13.5% (8.1%-20.0%). Studies from sites in countries with poorer economic status had higher recovery proportions. However, there were no statistically significant differences when the estimates were stratified according to sex, midpoint of intake period, strictness of the diagnostic criteria, duration of follow-up, or other design features. CONCLUSIONS: Based on the best available data, approximately, 1 in 7 individuals with schizophrenia met our criteria for recovery. Despite major changes in treatment options in recent decades, the proportion of recovered cases has not increased.