Longitudinal Study of Cognitive Variables in Women with Schizophrenia: 31-Year Follow-Up Study.

Objective: To longitudinally analyze the course of cognitive dimensions in schizophrenic women over a period of 31 years.

Method: Accidental sampling. Developmental longitudinal design. Diagnosis according to the ICD-10. Thirty institutionalized women were evaluated using the WAIS on three separate occasions (in 1981, 1997, and 2012). The data were analyzed using a repeated measures split-plot method.

Results: Patients scored one to two standard deviations below the average on the WAIS. At all three evaluation times, they scored consistently, significantly worse on Performance IQ scales than on Verbal IQ in the following sequence: Processing Speed (PS) < Perceptual Organization (PO) < Working Memory (WM) < Verbal Comprehension (VC). Longitudinally, there was a significant, linear average trend that was stable between the first and second assessments, with a significant drop in scores at the third evaluation on Performance IQ (η2 = .586) and Verbal IQ scales (η2 = .299). The same trend was observed in PS (η2 = .655) and WM (η2 = .438), while PO decreased across the three evaluations (η2 = .509) and no difference in VC was found (η2 = .126).

Conclusion: Patients with schizophrenia presented with a low cognitive level. Longitudinally, they had a stable, differential profile of WAIS factors until late life, when performance dropped significantly.