Dr. Howard and Colleagues Reply

To the Editor: We thank Dr. Taylor for raising several interesting questions about the consensus statement by the International Late-Onset Schizophrenia Group. Such issues have for many years intrigued those who see patients develop psychotic symptoms for the first time in later life. Schizophrenia is, indeed, currently conceptualized as a neurodevelopmental disorder, with onset in late adolescence and young adulthood, but our consensus group concluded that the research evidence base supports the existence of a minority group of patients who show all the features of schizophrenia, except that their illness onset is delayed into middle age. Such a psychosis, with onset after age 40, has been called late-onset schizophrenia since the 1940s (1). The evidence we reviewed does not support Dr. Taylor’s suggestion that these patients have a misdiagnosed atypical affective disorder.

The group with onset after age 60 has historically provoked more controversy. It is worth noting that Kraepelin did not coin the term “paraphrenia” to denote a later age at onset; he believed that such patients differ most from those with dementia praecox by their lack of affective flattening and personality deterioration (2). The term “late paraphrenia” never gained acceptance outside European psychiatry and was itself a source of ambiguity and dispute. Indeed, its originators intended that the patients it described be considered to have schizophrenia with an onset delayed into late life (3). This was not the view of the consensus group, as is reflected in the suggested name “schizophrenia-like psychosis.”

We agree with Dr. Taylor that psychotic symptoms are seen in elderly people with depression, delirium, and dementia. However, all such patients do not belong in the same category with the now well-recognized group of individuals who develop a schizophrenia-like illness after the age of 60 but do not have a cognitive or mood disorder or acute confusion. Dr. Taylor suggests that by diagnosing a person with schizophrenia we increase the chances of his or her being treated with antipsychotics. We do not believe that a diagnosis of schizophrenia necessitates a need for antipsychotic use. These drugs are appropriately labeled “antipsychotic,” not “antischizophrenic.” Indeed, schizophrenia patients constitute only a small minority of the elderly individuals who receive antipsychotic drugs.

We accept that cutoffs for age at onset will always be arbitrary and that our choice of terminology was on the basis of what little we know about what Kraepelin called “the darkest area of psychiatry” (2). Our hope is to stimulate further study and debate regarding such patients.