Symptomatic and Functional recovery: Does symptom severity affect the recovery of executive functioning in people with a psychotic disorder?

Background:
Recovery in psychotic disorder patients is a multidimensional concept that can include personal, symptomatic, societal and functional recovery. Here we define Functional Recovery (FR) as recovery or compensation after the loss or impairment of skills in different cognitive functions. Some of the most impaired cognitive functions in psychosis are the executive functions, whose impairment in people with a psychotic disorder can produce problems that are difficult to overcome, partly because treatment often focuses only on Symptomatic Recovery (SR). Although symptom severity may be a risk factor for longstanding impairments of executive functioning, the association is not always found. To date, there has been little research on the association between the 2.

Method
This study is part of the UP’S study, a longitudinal cohort study of patients with a psychotic disorder. The Behaviour Rating Inventory of Executive Functioning Adult version (BRIEF-A) was used to measure FR at baseline and after 1 year. SR was measured using the Positive and Negative Symptom Scale-Remission (PANSS-R), also at baseline and 1 year? At both time points, correlations were computed as cross-sectional analyses. For the longitudinal analysis, the difference scores were used to calculate generalized linear models. Model selection was based on the Wald-Chi square test.

Results
323 people were included for the baseline assessment of the UP’S study, 163 of whom had completed the T1 follow-up measurement at the time of this study. We found a moderate association between PANSS-R baseline scores and BRIEF-A baseline scores (β=3.76). While there was also an association between the PANSS-R score at baseline and the BRIEF-A difference scores (β=1.67), we found no association between the PANSS-R difference scores and the BRIEF-A differences scores.

Conclusion
Our finding that less overall symptom severity was associated with 1 year improvement in executive functioning suggests that symptom severity could be a way of improving executive functioning over a year. However, as no link was found within the year between changes in symptoms and changes in executive functioning, it is possible that symptom severity does not have an immediate effect on executive functioning, but that its effect is delayed. This leaves scope for targeted interventions to improve executive functioning, and thus functional recovery.