Neurocognitive and clinical correlates of insight in schizophrenia

Schizophrenia is a heterogeneous disorder characterized by various symptom dimensions and neurocognitive deficits. Impairment of insight is a core clinical symptom of the disorder. There has been an increasing focus on neurocognition and insight in schizophrenia; although, many studies fail to control for premorbid cognitive status.

Schizophrenia patients (n = 60) selected for adequate background education were recruited from outpatient services of a tertiary care hospital and community care homes in Southern India. These patients were comprehensively assessed using a neurocognitive battery. Clinical assessments were done using the Positive and Negative Syndrome Scale (PANSS) and Schedule for the Assessment of Insight-expanded version (SAI-E). Partial correlation was performed to examine the relationship of insight with clinical and neurocognitive measures. Statistical significance was set at P = 0.004 (Bonferroni correction for 12 tests of association). Linear regression analysis was performed to examine the predictors of insight.

The mean PANSS positive, negative, general psychopathology, and total scores were 14.2 ± 4.9, 17.4 ± 5.0, 34.3 ± 6.8, and 65.8 ± 13.9, respectively. Mean insight score (SAI-E) was 8.5 ± 2.9. In partial correlation done after controlling for IQ, significant negative correlations were observed between insight score and the Wisconsin Card Sorting Test (WCST) total errors (P = 0.001), WCST perseverative errors (P < 0.001). Insight scores had negative correlations with PANSS negative (P < 0.002) and total scores (P < 0.002). WCST perseverative errors were the primary predictor of insight in the regression analysis.

Insight has a strong relationship with executive functioning in schizophrenia. This could indicate shared neurobiological substrates for insight and executive functioning.