Prevalence rates of 鈥渟ymptomatic remission鈥?(symptom criteria only) and 鈥渆nduring remission鈥?(symptom and 6-month time criteria), defined according to , were determined in first-episode patients participating in a RCT by the German Research Network on Schizophrenia (GRNS) that compared post-acute, 1-year maintenance treatment with risperidone or haloperidol. Respective predictors at baseline were identified by logistic and Cox regression analysis.
Prevalence rates were 91.5% for symptomatic remission (n = 152/166 eligible patients) and 58.6% for enduring remission (n = 65 of 111 patients who continued for at least 6 months; 39.2% of all 166 patients included), with no significant differences between risperidone and haloperidol in either type of remission. Enduring remission often was not reached because of negative symptoms: After 6 months, 40.5% of the patients had at least 1 negative symptom, whereas only 10.8% of the patients had 鈥減ersisting鈥?positive symptoms. Of the different predictors identified in univariate analyses, (lower) negative symptoms and participating in standardized psychological treatment remained significant in multivariate (stepwise forward) analyses for enduring remission.
By far most of the first-episode patients reached a temporary state of full symptomatic remission within 1 year of antipsychotic treatment. However, only about 50% achieved sustained, enduring remission. Negative symptoms are still a major treatment obstacle to enduring remission in schizophrenia.