Regular Research Articles
Schizophrenia Spectrum Disorders in Later Life: Prevalence and Distribution of Age at Onset and Sex in a Dutch Catchment Area

https://doi.org/10.1097/JGP.0b013e3182011b7fGet rights and content

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.

Section snippets

Catchment Area Characteristics

The psychiatric catchment area of the southern district of Amsterdam is a geographically well-defined urban area comprising 17.5% of the total Amsterdam population. The district includes a variety of neighborhoods, ranging from lower-class housing to upper-class residences, and is highly urbanized, with a population density of 8,320 inhabitants/km2, compared with 486 inhabitants/km2 for the Netherlands as a whole. On January 1, 2008, 25.631 (19.6%) of the catchment area inhabitants were age 60

Sample Characteristics

Demographic and clinical characteristics of the 183 included patients are listed in Table 2. The median age was 67 years (range: 59–95), while the median age at onset was 34 years (range: 15–88). In 118 patients (64.5%), who provided informed consent for the larger study, diagnosis was confirmed through the diagnostic interview. Sixty-five patients (35.5%) were not able or willing to provide informed consent. In these nonconsenting patients, inclusion diagnosis was confirmed through the

DISCUSSION

In this service-based sample of older patients, the estimated one-year prevalence of schizophrenia including spectrum disorders was 0.71% and the prevalence of schizophrenia alone was 0.55%. Substantial proportions of both patients with schizophrenia including spectrum disorders (38.8%) and patients with schizophrenia alone (36.4%) were age 40 years or older at onset. The estimated prevalence of schizophrenia among women (0.68%; 95% CI: 0.56–0.83) was almost twice as high as the estimated

References (34)

  • MJ Harris et al.

    Late-onset schizophrenia: an overview

    Schizophr Bull

    (1988)
  • A Aleman et al.

    Sex differences in the risk of schizophrenia: evidence from meta-analysis

    Arch Gen Psychiatry

    (2003)
  • DJ Castle et al.

    The epidemiology of late-onset schizophrenia

    Schizophr Bull

    (1993)
  • H Hafner et al.

    Causes and consequences of the gender difference in age at onset of schizophrenia

    Schizophr Bull

    (1998)
  • RC Bland et al.

    Prevalence of psychiatric disorders in the elderly in Edmonton

    Acta Psychiatr Scand

    (1988)
  • JS Bamrah et al.

    Epidemiology of schizophrenia in Salford, 1974–84. Changes in an urban community over ten years

    Br J Psychiatry

    (1991)
  • SJ Keith

    Schizophrenic disorders

  • Cited by (68)

    • Schizophrenia in Older Adults

      2022, Comprehensive Clinical Psychology, Second Edition
    View all citing articles on Scopus

    The authors thank Wouter van Ewijk for chairing the expert panel, and Peter van de Ven for statistical assistance.

    This study was supported by a grant from the “Stichting tot Steun VCVGZ,” which had no further role in the study design, collection, analysis, and interpretation of the data; in the writing of the report; and in the decision to submit the article for publication.

    Paul D. Meesters is an unrestricted grant holder with AstraZeneca.

    View full text