By Eleanor McDermid, Senior medwireNews Reporter
Remission of positive and negative symptoms is the most important predictor of functional outcomes among patients with first-episode psychosis, with cognition having only a small impact, say researchers.
Ashok Malla (McGill University, Montreal, Quebec, Canada) and team found that the length of remission of negative symptoms had the largest effect on functional outcomes 1 year after psychosis onset. However, remission of positive symptoms had a prominent effect on 2-year outcomes, which they say illustrates “the importance of achieving lengthy remissions of both positive and negative symptoms.â€
The researchers assessed 208 patients for functional outcomes on the Strauss Carpenter Scale 1 year after first-episode psychosis, at which point 30.0% had been in total symptom remission for an average of 2.4 months. Of 159 assessed after 2 years, 41.5% had been in total remission for an average of 5.7 months.
A model that included age, medication compliance, duration of untreated psychosis, substance abuse and premorbid adjustment accounted for only a very small proportion of the variance in functional outcomes at either 1 or 2 years. Adding verbal memory, measured on the Wechsler Memory Scale-III after treatment initiation when the patients were considered stable, increased the proportion of variance explained, but only to about 9% in both cases.
By contrast, adding the length of total remission increased the variance explained to 30% for 1-year outcomes and 29% for 2-year outcomes.
Negative symptoms made the largest contribution to 1-year outcomes; a baseline model including length of remission of positive symptoms explained 15% of the variance in functional outcomes, but adding negative symptom remission explained an additional 20%.
Remission of negative symptoms was difficult to achieve at both time points, with 33.2% and 48.4% of patients achieving this at 1 and 2 years, respectively, compared with 67.8% and 69.2% who achieved remission from positive symptoms.
However, positive symptoms had a more substantial effect on 2-year outcomes; together with other baseline variables, length of positive symptom remission explained 24% of the variance in functioning, while adding remission of negative symptoms explained an additional 13% of the variance.
“The difficulties associated with achieving complete remission underline the importance of searching for effective treatment of persistent positive and, especially, negative symptomsâ€, writes the team in the Journal of Clinical Psychiatry.
Licensed from medwireNews with permission from Springer Healthcare Ltd. ©Springer Healthcare Ltd. All rights reserved. Neither of these parties endorse or recommend any commercial products, services, or equipment.