The Influence of Age and Sex on the Onset and Early Course of Schizophrenia

Abstract

A new standardised interview for the retrospective assessment of onset and early course of schizophrenia (IRAOS) was used to study the influence of age and sex on time of onset and psychopathology before first admission in 267 schizophrenic patients admitted for the first time. Mean age at onset, according to various operationalised definitions, differed by three to four years between the sexes. The age distribution at the earliest sign of mental disorder showed an early and steep increase until the age of 25 in males, and a delayed and smaller increase in females, with a second peak in women aged 45-79. Schizophrenia began with negative symptoms in 70% of cases, appearing two to six years before admission, and all positive symptoms appearing up to two years before. Both positive and negative symptoms accumulated exponentially. The early course of the disease was similar across age groups, except there was a longer period of negative symptoms before first admission in late-onset schizophrenia in women. The few significant age differences in symptoms were presumably due to general age-dependent reaction patterns like anxiety and depression or the cognitive development of personality, as indicated by an increase in fully elaborated positive symptoms, especially systematised paranoid delusions, with age.

Specificity of childhood psychotic symptoms for predicting schizophrenia by 38 years of age: a birth cohort study

“…This confirms a previous report (Poulton et al 2000) from this cohort when the study members were aged 26 and extends the results further into the period of risk for development of schizophrenia (Hafner et al 1993), providing us with greater confidence that we have captured the majority of likely adult schizophrenia cases. The association between strong age-11 psychotic symptoms and adult schizophrenia was also robust to a range of potential confounders including gender, family socio-economic background and the presence of childhood psychiatric disorders.…”

“…In the original study (Poulton et al 2000) we only followed individuals up to 26 years of age and children in the Welham et al (2009) study were only followed to age 21. As participants in both of these studies were only part-way through the main period of risk for developing schizophrenia (Hafner et al 1993), it is possible that some cases of schizophrenia had not yet developed, resulting in an underestimate of the predictive utility of childhood psychotic symptoms for later schizophrenia. Similarly, the samples reported in Kelleher et al (2012b) had an upper age limit of 16 years, only explored the presence of non-psychotic psychiatric disorders (thus providing no information on schizophrenia risk), and only focused on current co-occurrence with psychotic symptoms, which does not tell us about their future predictive value for disorders in adulthood.…”

Computerized Neurocognitive Scanning: II. The Profile of Schizophrenia

“…However, although the over-all profile was similar in men and women with schizophrenia, the correlations between neurocognitive performance and clinical measures were more ubiquitous and higher for women. This sample manifested the clinical features that have been reported to differ for men and women with schizophrenia, including earlier age of onset and more severe negative symptoms in men (Angermeyer et al 1990;Gur et al 1996;Häfner et al 1993). On the other hand, with the exception of verbal memory, in which women with schizophrenia were less impaired than men, women were equally impaired as men in both speed and accuracy of performance and were more impaired than men for spatial accuracy.…”

Additional support for the cognitive model of schizophrenia: evidence of elevated defeatist beliefs in schizotypy

“…Consistent with previous studies and due to the relatively high functioning of college students [28][29][30], we used a relatively conservative approach of including only the top 5% of scorers in the schizotypy group. Eligibility criteria also included being between 18 and 30 years old (n = 9 excluded; those over 30 were excluded because they are outside of the highest risk period for schizophrenia onset [31,32]), being fluent in English (n = 1 excluded), reporting not being under the influence of substances during testing (n = 1 excluded), and having no self-reported diagnosis of a schizophrenia-spectrum disorder (n = 1 excluded). Participants meeting criteria were invited to the laboratory phase of the study where they completed measures of defeatist performance beliefs, quality of life, depression, and working memory.…”