Premorbid adaptability: predictors of cognitive dysfunction in schizophrenia

Premorbid adaptation (PA) in social life and professional activities of patients with schizophrenia is a key factor in assessing cognitive function. Despite numerous studies examining the relationship between cognitive impairment indicators and premorbid adaptation in schizophrenia patients, clear correlational results have not been obtained. A variety of outcomes was observed. The aim of this study is to investigate the multifaceted relationship between academic and social PA and cognitive impairment indicators after disease onset at each developmental stage (childhood, early and late adolescence) in individual schizophrenia patients, based on anamnestic data. Accordingly, this research explores possible differential connections and interrelationships between the progression of PA deterioration and post-onset cognitive impairments. Eighty-five patients with schizophrenia were assessed using the Premorbid Adjustment Scale (PAS). General cognitive ability, verbal IQ, verbal memory and learning, working memory, executive function, premorbid IQ, and information processing speed were measured. Correlation analysis showed that low academic PA in childhood and early adolescence is associated with deterioration in verbal IQ, working memory, verbal learning, and executive function. Deterioration of academic PA in early and late adolescence is linked to a decrease in verbal learning and executive function, which, according to additional analysis results, predicts a decrease in IQ. It has been established that academic PA is associated only with cognitive impairments after disease onset. New data have been obtained on the specific significance of each developmental stage in the formation of academic PA in relation to post-onset cognitive function. Early premorbid academic adaptation impairment likely leads to the onset of cognitive decline, resulting in post-diagnostic cognitive impairment.