There is preliminary evidence that cognitive functioning is influenced by premorbid adjustment. The goal of this study was to examine to what extent premorbid adjustment patterns are related to cognitive functioning in a cohort of first-episode psychosis.

Seventy-seven neuroleptic-naïve patients with a first-episode of psychosis underwent clinical and neuropsychological assessments at baseline, 1 month and at 6 months of follow-up. Cognitive measurements included were: Verbal Fluency Test, Trail Making-B Test, Wechsler Memory Test, Reaction Time task, Wisconsin Card Sorting Test (WCST) perseverative errors. Patterns of premorbid functioning were categorised in two groups: ‘stable-good’ group and ‘poor and declining’ group, using the Cannon-Spoor Premorbid Adjustment Scale.

No significant associations were found between premorbid adjustment change scores and cognitive variables in the stable-good adjustment group. Patients with premorbid deterioration change score in premorbid adjustment between childhood and early adolescence was associated significantly with lower improvement at the follow-up in the Wechsler Memory Test (r=-0.511; p=0.009) and Reaction Time task (r=0.435; p=0.030). Moreover, change score in premorbid adjustment between early and late adolescence was significantly associated with lower improvement in perseverative errors (r=-0.455; p=0.022).

Deterioration of premorbid adjustment was significantly associated with lower improvement of cognitive improvement at the 6 months follow-up in a first episode psychosis. This lower cognitive improvement varied with the timing of the deterioration process in premorbid adjustment. Early adolescence premorbid deterioration was associated with less improvement in attentional and memory tasks. And premorbid deterioration in the late adolescence was related to lower improvement on executive tests.