Hostname: page-component-84b7d79bbc-fnpn6 Total loading time: 0 Render date: 2024-08-01T14:22:40.279Z Has data issue: false hasContentIssue false

Is the decline in diagnoses of schizophrenia caused by the disappearance of a seasonal aetiological agent? An epidemiological study in England and Wales

Published online by Cambridge University Press:  01 March 1998

MARCO PROCOPIO
Affiliation:
From the Royal London Hospital (St Clement's), London; and Department of Mathematics and Statistics, University of Surrey, Guildford, Surrey
PAUL K. MARRIOTT
Affiliation:
From the Royal London Hospital (St Clement's), London; and Department of Mathematics and Statistics, University of Surrey, Guildford, Surrey

Abstract

Background. Studies from several countries have shown a decline, in the last few decades, of the number of admissions with a diagnosis of schizophrenia. This could be due to a fall in the incidence of schizophrenia, but it also could be due to confounding factors. The hypothesis tested in the study is that the incidence of schizophrenia is actually falling because of a decrease in the presence of a seasonal aetiological agent.

Methods. The hypothesis was tested by analysing the dates of birth of the patients discharged with a diagnosis of schizophrenia from NHS hospitals in England and Wales and would be confirmed by an appropriate change in the seasonality of the births over time.

Results. Evidence of seasonality has been observed in the schizophrenic births, but with no significant change over time.

Conclusions. The fall in first admissions with a diagnosis of schizophrenia does not seem to be due to a change in the prevalence of a seasonal aetiological factor. Therefore, either there has been a reduction in incidence due to a change in a non-seasonal agent, or the incidence of schizophrenia is not changing and the fall in first admissions is due to confounding factors.

Type
Research Article
Copyright
© 1998 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)