Diagnostic features of the cycloid psychoses in a first psychotic episode sample

INTRODUCTION

The cycloid psychoses have not been included in the modern classifications-what makes scientific research difficult. The aim of the present study is to investigate the presence and specific characteristics of the cycloid psychoses in a broad sample of first psychotic episodes.

METHODS

Seventy patients diagnosed with one-year first schizophrenia episode, schizophreniform disorder, or schizoaffective disorder were studied (mean age, 27.9 years old; SD±6.34). The detection of the possible cases of cycloid psychosis was done according to the Perris and Brockington operational criteria. Two groups of "cycloid" (n=11) and "non cycloid" (n=59) patients were compared according to demographic and clinical variables, and possible diagnostic variables were evaluated by the ROC curves.

RESULTS

Significant differences were found between cycloid and non cycloid groups for a number of clinical variables: prodromic symptoms (p<0.001), PANSS total score (p=0.003), PANSS-P (p=0.009), PANSS-GP (p=0.001), total score for mania by EVMAC (p=0.001), and CDSS for depression (p=0.004). ROC curves were significant for PANSS-GP (AUC=0.791, p=0.002), EVMAC (AUC=0.938, p=0.001), and CDSS (AUC=0.770, p=0.005). A sensitivity/specificity study demonstrated a negative predictive value for PANSS-GP (93.88%), EVMAC (96.30%), and CDSS (93.88%).

CONCLUSIONS

According to these results, cycloid psychoses might represent differentiated and well-defined clinical entity.