Diagnostic stability in subjects with multiple admissions for psychotic illness

Abstract

This study describes the demographic, admission and diagnostic characteristics of a group of 204 subjects from the Royal Edinburgh Hospital who received exit diagnoses according to the functional psychoses over the 2 year period 1993 - 1994. In total, 737 admissions were analysed using the OPCRIT computer program (McGuffin et al, 1991 ), and diagnoses were analysed in accordance with a number of operational criteria. The main results are summarised as follows:

1. Subjects with schizophrenia had by far the highest mean admission length per year, and almost twice the total length of admission than other subjects, and the demographic results confirmed the socially catastrophic nature of the condition.

2. The results of the diagnostic spread confirmed that considerable diagnostic differences between different sets of operational criteria are common.

3. There was an increase in the frequency of diagnosis of schizophrenia from initial episode across all admissions according to all sets of diagnostic criteria.

4. High levels of stability in the region of 80% were found for schizophrenia according to most sets of operational criteria, while the affective disorders displayed moderate stability levels which varied more widely between different sets of operational criteria. Other conditions, nonorganic psychotic disorders, delusional disorder, atypical psychosis and schizoaffective disorder displayed poor levels of stability.

5. More than 50% of subjects changed diagnosis between episodes one and five , confirming that diagnostic movement is common. According to clinical criteria, there was regular triangular movement between the diagnoses of depression, mania and bipolar disorder, and according to a11 sets of criteria there was considerable movement from 'no diagnosis' to a range of other psychiatric disorder. There was very Jittle movement away from a diagnosis of schizophrenia towards other major psychiatric disorder, but considerable early movement from other conditions towards more clearly defined diagnoses.

The results confirmed some of the limitations of operational criteria, and the implications of the findings are discussed.