10 year course of IQ in first-episode psychosis: relationship between duration of psychosis and long-term intellectual trajectories

Impact of cognitive reserve in clinical, neurocognitive and lifestyle factors in chronic schizophrenia and early stages of schizophrenia

INTRODUCTION

Although there is evidence that higher cognitive reserve (CR) is a protective factor and it has been related to better prognosis, there have been no studies to date that have explored the CR level and its impact in clinical, neurocognitive and lifestyle outcomes according to the stage of the disease: early stage of psychosis (ESP) or chronic schizophrenia (SCZ).

MATERIAL AND METHODS

A total of 60 patients in the ESP and 225 patients with SCZ were enrolled in the study. To test the predictive capacity of CR for each diagnostic group, a logistic regression analysis was conducted. Hierarchical linear regression analyses were performed to explore the associations between CR and different outcomes. The mediation analyses were performed according to the principles of Baron and Kenny.

RESULTS

Patients with SCZ showed lower CR than those in the ESP (p<0.001). CR correctly classified 79.6% of the cases (p<0.001; Exp(B)=1.062). In ESP group, CR was related to working memory (p=0.030) and negative symptoms (p=0.027). CR (t=3.925, p<0.001) and cannabis use (t=2.023, p=0.048) explained 26.7% of the variance on functioning (p=0.003). In patients with SCZ, CR predicted all cognitive domains, negative symptoms (R2=0.091, p=0.001) and functioning (R2=0.074, p=0.005). In both ESP and SCZ groups, higher CR was associated with lower body mass index and circumference. In ESP group, the effect of adherence to Mediterranean diet on functioning (p=0.037) was mediated by CR level (p=0.003).

CONCLUSIONS

The implications of CR depend on the stage of the disease (ESP vs. SCZ), with a greater effect on neurocognition and negative symptoms in patients with chronic SCZ.

Course of intellectual functioning in schizophrenia and bipolar disorder: a 10-year follow-up study

BACKGROUND

Intellectual functioning (IQ) is lower in schizophrenia patients compared to healthy controls, with bipolar patients intermediate between the two. Declines in IQ mark the onset of schizophrenia, while stability is generally found post-onset. There are to date few studies on long-term IQ development in bipolar disorder. This study presents 10-year follow-up data on IQ, including premorbid IQ estimates, to track the developmental course from pre-onset levels to long-term outcomes in both patient groups compared to healthy controls.

METHODS

We included 139 participants with schizophrenia, 76 with bipolar disorder and 125 healthy controls. Mixed model analyses were used to estimate developmental slopes for IQ scores from estimated premorbid level (NART IQ) through baseline (WASI IQ) measured within 12 months post-onset, to 10-year follow-up (WASI IQ), with pairwise group comparisons. The best fit was found using a model with a breakpoint at baseline assessment.

RESULTS

Only the schizophrenia group had significant declines from estimated premorbid to baseline IQ levels compared to controls. When comparing patient groups, schizophrenia patients had steeper declines than the bipolar group. Increases in IQ were found in all groups over the follow-up period.

CONCLUSIONS

Trajectories of IQ from premorbid level to 10-year follow-up indicated declines from estimated premorbid level to illness onset in both patient groups, followed by increases during the follow-up period. Schizophrenia patients had a steeper decline than bipolar patients. During follow-up, increases indicate developmental improvement for both patient groups, but with a maintained lag compared to healthy controls due to lower premorbid levels.

Ten-year course of cognition in first-episode non-affective psychosis patients: PAFIP cohort

BACKGROUND

A large body of research states that cognitive impairment in schizophrenia is static. Nevertheless, most previous studies lack a control group or have small study samples or short follow-up periods.

METHOD

We aimed to address these limitations by studying a large epidemiological cohort of patients with first-episode schizophrenia spectrum disorders and a comparable control sample for a 10-year period.

RESULTS

Our results support the generalized stability of cognitive functions in schizophrenia spectrum disorders considering the entire group. However, the existence of a subgroup of patients characterized by deteriorating cognition and worse long-term clinical outcomes must be noted. Nevertheless, it was not possible to identify concomitant factors or predictors of deterioration (all Ps > 0.05).

CONCLUSIONS

Cognitive functions in schizophrenia spectrum disorder are stable; however, a subgroup of subjects that deteriorate can be characterized.

Entire duration of active psychosis and neurocognitive performance in first-episode non-affective psychosis

AIM

To explore if the entire duration of active psychosis (DAP) is related to neurocognitive performance at baseline and at 3-year follow-up in patients with first episode psychosis (FEP).

METHODS

DAP was estimated for 481 FEP patients. A neuropsychological battery was administered to measure neurocognitive specific domains, and a global indicator of neurocognitive impairment (global deficits score, GDS) was calculated. According to the DAP quartiles, four subgroups were formed, and these were compared. In addition, a logistic regression analysis was carried out to predict neurocognitive impairment at 3-year follow-up.

RESULTS

FEP patients with the longest DAP (more than 18.36 months) presented a more severe global neurocognitive impairment evidenced in their GDS, both at baseline (F = 5.53; p˂ .01) and at 3-year follow-up (F = 4.16; p˂ .01). Moreover, a subgroup of participants with DAP between 7.40 and 18.36 months showed a specific attentional decline over the 3-year follow-up (F = 3.089; p˂ .05).The logistic regression model showed that sex (Wald = 7.29, p < .010), premorbid adjustment (Wald = 7.24, p < .010), attention (Wald = 12.10, p < .001), verbal memory (Wald = 16.29, p < .001) and visual memory (Wald = 9.41, p < .010) were significant predictors of neurocognitive impairment 3 years after the FEP. The variables composing the DAP were not significant predictors in this model.

CONCLUSIONS

DAP seems to be related to global neurocognitive impairment in FEP patients. These findings contribute in several ways to our understanding of the effects of active psychosis on the brain, and provide the basis for future research.

Premorbid functioning in schizophrenia spectrum disorders with comorbid substance use: A systematic review

Premorbid functioning has been related with several clinical features and prognosis of schizophrenia spectrum disorders. Comorbidity with substance use is highly prevalent and usually hinders clinical improvement in this kind of psychiatric disorders. This systematic review analyzes the differences in the premorbid functioning of subjects with a schizophrenia spectrum disorder with substance use (SSD+, dual psychosis) or without it (SSD-). A systematic review (PRISMA guidelines), including search in electronic databases (MEDLINE, Web of Science, and Cochrane Library), was performed. 118 published works were considered of which only 20 met our inclusion criteria. Although there is a great variability in methodologies, diagnoses included, and substances used, studies using the Premorbid Functioning Scale to assess the academic and/or social domains found that SSD+ subjects had a poorer academic but better social premorbid functioning than those with SSD-. Current evidence is not conclusive, so additional studies are required to integrate intervening factors in order to clarify the clinical implications of premorbid functioning to improve the course and therapeutic response of patients.

Active psychosis and pro-inflammatory cytokines in first-episode of psychosis

Higher levels of pro-inflammatory cytokines are consistently found in the serum of first episode psychosis (FEP) patients and this immune dysfunction could contribute to neural harm. On the other hand, lengthy periods of active psychosis during the early phases of the illness appear to be associated to worst functional outcome. We aim to explore the possible relationship between lengthy periods of active psychosis during early phases of the illness and the levels of pro-inflammatory cytokines. This is a prospective clinical study consisting of a 3-year clinical follow-up. We assessed the relation between the duration of active psychosis in patients with FEP and the serum levels of 21 cytokines at baseline and 3 months after initiating antipsychotic medication. We used the Human High Sensitivity T Cell Magnetic Bead Panel protocol from the Milliplex® Map Kit. The sample consisted of 59 patients with a FEP. The percentage of variation of the serum levels of the chemokine MIP-3α during the first 3 months of antipsychotic treatment and the score in negative psychotic symptoms 3 months after the initiation of antipsychotic medication, acted as predictors of the initial time to remission of positive psychotic symptoms. Our findings open the possibility to investigating the potential use of the variation in chemokine MIP-3α serum levels during the first months of antipsychotic treatment to identify a subtype of FEP patients that could benefit from an add-on treatment with immune modulators. CLINICALTRIALS.GOV ID: NCT02897167. DATE OF FIRST REGISTRATION: September 13, 2016. "Study of the Activation of Proinflammatory Pathways of Toll-like Receptors in Schizophrenia Patients (PAFIP_TLR)". https://clinicaltrials.gov/ct2/show/NCT02897167.

Association Between the Duration of Untreated Psychosis and Selective Cognitive Performance in Community-Dwelling Individuals With Chronic Untreated Schizophrenia in Rural China

IMPORTANCE

Cognitive deficits constitute core features of schizophrenia, but the trajectories of cognitive difficulties in chronic untreated schizophrenia remain unclear.

OBJECTIVE

To assess the association of neuropsychological deficits with duration of untreated psychosis in individuals with chronic untreated schizophrenia.

DESIGN, SETTING, AND PARTICIPANTS

Community-dwelling individuals with chronic untreated schizophrenia (untreated patient group) and individuals without mental illness (control group) were recruited from predominantly rural communities in Ningxia, China between June 20, 2016, and August 6, 2019, and administered the Structured Clinical Interview for DSM-IV, the Mini-Mental State Examination, an 8-test version of the MATRICS Consensus Cognition Battery adapted for use in individuals with low levels of education, and a measure of social cognition.

MAIN OUTCOMES AND MEASURES

Comparison of cognitive test scores between the two groups and association of cognitive test scores with duration of untreated schizophrenia.

RESULTS

The patient group included 197 individuals with chronic untreated schizophrenia (101 men [51.3%]; mean [SD] age, 52.1 [11.8] years; median [interquartile range] years of schooling, 3 [0-6] years; median [interquartile range] years of untreated psychosis, 22.9 [14.9-32.8] years). The control group included 220 individuals (118 men [53.6%]; mean [SD] age, 52.1 [11.2] years; median [interquartile range] years of schooling, 4 [0-6] years). The untreated patient group performed significantly worse than the control group on all cognitive measures (adjusted partial Spearman correlation coefficient [Spearman ρ] ranged from -0.35 for the revised Chinese version of the Reading the Mind in the Eyes Test to -0.60 for the Brief Visuospatial Memory Test-Revised; P < .001 for all comparisons). Longer durations of untreated psychosis were associated with lower performance in 3 MATRICS Consensus Cognition Battery measures assessing different aspects of executive functioning (Brief Visuospatial Memory Test-Revised [ρ = -0.20; P = .04]; Brief Assessment of Cognition in Schizophrenia, Symbol Coding subtest [ρ = -0.35; P < .001]; and Neuropsychological Assessment Battery, Mazes subtest [ρ = -0.24; P = .01]). The median duration of untreated psychosis (22.9 years) was associated with estimated score reductions in the 3 measures of 34% (95% CI, 10%-52%), 43% (95% CI, 28%-55%), and 57% (95% CI, 31%-73%), respectively.

CONCLUSIONS AND RELEVANCE

The findings of this study suggest that long-term untreated schizophrenia was associated with decreases in selective cognitive abilities; both neurodegenerative pathology and neurodevelopmental dysfunction may be factors in cognition in persistent psychosis. Expanding research to include cohorts of patients from underserved rural communities in low- and middle-income countries may provide new insights about the etiological factors, disease course, and management of schizophrenia.

Duration of active psychosis during early phases of the illness and functional outcome: The PAFIP 10-year follow-up study

INTRODUCTION

Longer duration of active psychosis (presence of positive psychotic symptoms) has been associated to worsening of functional and symptomatic outcome in patients with a first-episode of psychosis. There could be a "critical period" of increased brain vulnerability in the early phases of the illness when the effect of active psychosis would be exceptionally pernicious.

OBJECTIVES

We aim to explore the impact of lengthy periods of active psychosis during early phases of illness on long-term functional outcome.

METHODS

This is a prospective clinical study. We assessed the effect of the duration active psychosis in patients with a first-episode of nonaffective psychosis on long-term social functioning and functional recovery. The study consisted of a 3-year clinical follow-up and a functional evaluation performed after a 10-year period.

RESULTS

The sample consisted of 169 patients with a first-episode of non-affective psychosis. The duration of active psychosis after treatment (DAT) during the 3-year clinical follow-up acted as predictor of social functioning at the 10-year functional evaluation (Wald: 10.705; p = .001), but not of functional recovery. The duration of untreated psychosis (DUP) did not act as a predictor of any of the two long-term measures of functional outcome.

CONCLUSIONS

Active psychosis in early phases of the illness seems to be correlated to worst long-term functionality. In this study the duration of active psychosis after treatment (DAT) was a better predictor of long-term outcome than the duration of untreated psychosis (DUP). Reducing DAT should be considered an important objective for early intervention programs.

Physical Comorbidities are Independently Associated with Higher Rates of Psychiatric Readmission in a Chinese Han Population

BACKGROUND

In people with psychosis, physical comorbidities are highly widespread and leading contributors to the untimely death encountered. Readmission rates in psychiatric patients are very high. Somatic comorbidities could be one of the considerable risk factors for psychiatric rehospitalization. Nevertheless, much less is known about the relation between physical comorbidities and psychiatric readmission. We aimed to investigate the association between physical comorbidities and psychiatric readmission in Han Chinese patients with psychiatric disorders.

METHODS

We used administrative data for January 1, 2009 to December 31, 2018 from the headquarters of the Affiliated Brain Hospital of Guangzhou Medical University to identify adults with schizophrenia, unipolar depression or bipolar disorder discharged from hospital. Data were extracted on sociodemographic and clinical characteristics. The Charlson comorbidity index (CCI) was used to assess the existence of significant physical comorbidity. Cox proportional hazards regression estimated rehospitalization risk after discharge.

RESULTS

A total of 15,620 individuals were included in this study, with the mean age of 35.1 years (SD = 12.8), and readmission occurred for 23.6% of participants. Survival analysis showed that physical comorbidities were statistically and significantly associated with psychiatric readmission, even after the adjustment for the number of psychiatric comorbidities, other sociodemographic and clinical variables.

CONCLUSION

Our results suggest that somatic comorbidities are related with higher rates of psychiatric readmission. Hence, to treat psychosis more effectively and to reduce rehospitalization, it is crucial to treat physical comorbidities promptly and adequately. It is absolutely necessary to bring somatic comorbidities to the forefront of psychiatric treatment and research.

Premorbid adjustment predictors of cognitive dysfunction in schizophrenia

Premorbid adjustment (PA) in academic and social domain is a key-predictor of cognitive performance in schizophrenia. Prior studies provided inconsistent findings regarding the differential relationships of PA domains with post-illness cognition. Multivariate associations of academic and social PA in each developmental stage (childhood, early and late adolescence) with post-onset cognitive variables were explored. Furthermore, possible differential relationships of PA domain deterioration courses with post-onset cognitive dysfunction were investigated. Seventy-five schizophrenia patients were evaluated with Premorbid Adjustment Scale (PAS). General cognitive ability, verbal IQ, verbal memory and learning, processing speed, working memory, executive function and premorbid IQ were assessed. Canonical Correlation Analyses revealed that poorer academic PA across childhood and early adolescence was related to worse post-onset verbal IQ, working memory, verbal learning and executive function, while academic PA deterioration between early and late adolescence was associated with poorer verbal learning and executive function and, as further analysis indicated, predicts IQ decline. Academic PA was exclusively associated with post-onset cognitive impairment. New evidence emerged for the specificity of each developmental period in constructing academic PA in its relation to post-illness cognition. Early premorbid academic maladjustment possibly constitutes the onset of a cognitive dysmaturational process which results to post-diagnosis impaired cognition.

Long term effect of early intervention service on duration of untreated psychosis in youth and adult population in Hong Kong

AIM

The current study explored the effect of an early intervention (EI) service for psychosis in Hong Kong (EASY) on the reduction of the duration of untreated psychosis (DUP) at 10 years, in adolescent and adult patients.

METHOD

Data from three first-episode psychosis (FEP) studies conducted over 10 years using the same DUP assessment was analysed. FEP study 1 year before the EI service (2000) was used as a control, with those aged <25 comprising the youth psychosis control group and those aged over 25 comprising the adult psychosis control group. Data from the EASY service collected in 2010 constituted the youth psychosis EI group and data from an adult EI service collected from 2009 to 2011 constituted the adult psychosis EI group. DUP of EI and control groups was compared. The effect of the mode of onset and family history of psychosis on DUP was studied.

RESULTS

DUP in the adult group was significantly reduced from median of 180 days to 93 days after 10 years (U = 12 906.50, P = 0.01), particularly in those with gradual onset and without family history. However, no significant change of DUP was found in the youth psychosis group.

CONCLUSIONS

Results of the current study provide evidence that EI programmes with public awareness campaign can significantly reduce DUP of adult patients but not in youth group. The effect is more specific in those with long DUP. Further research should explore the specific factors contributed to the long DUP of patients of different age groups so as to establish targeted intervention strategies.

Duration of active psychosis and functional outcomes in first-episode non-affective psychosis

BACKGROUND

The duration of untreated psychosis (DUP) has been associated with negative outcomes in psychosis; however, few studies have focused on the duration of active psychotic symptoms after commencing treatment (DAT). In this study, we aimed to evaluate the effect of DUP and DAT on functional long-term outcomes (3 years) in patients with early psychosis.

METHODS

We evaluated the Scale for the Assessment of Positive Symptoms (SAPS) at frequent intervals for 3 years after presentation to determine the DAT for 307 individuals with first-episode psychosis together with DUP and clinical variables. The functional outcomes were assessed using the Disability Assessment Scale (DAS) at three years, and functional recovery was defined as minimal impairment and return to activity. Associated variables, DAT and DUP were included in logistic regression models to predict functional outcomes. Receiver operating characteristic curves and Youden's index were applied to assess the best cut-off values.

RESULTS

DAT, (Wald: 13.974; ExpB: 1.097; p < 0.001), premorbid adjustment, initial BPRS score, gender, age of onset and schizophrenia diagnosis were significant predictors of social functioning, whereas only premorbid adjustment (Wald: 11.383; ExpB:1.009), DAT (Wald: 4.850; ExpB: 1.058; p = 0.028) and education were significant predictors of recovery. The optimal cut-off of DAT for predicting social functioning was 3.17 months for DAT (sensitivity: 0.68; specificity: 0.64; Youden's index: 0.314).

CONCLUSIONS

DAT is strongly related to functional outcomes independent of the DUP period or other variables. As a modifiable variable, the reduction of the DAT should be considered a main focus of intervention from the onset of the illness to improve long-term outcomes.

Openness to experience shortens duration of untreated psychosis in Serbian clinical population

AIM

To determine duration of untreated psychosis (DUP) in patients with schizophrenia-spectrum disorders from Serbia and to analyse factors that potentially contribute to the treatment delay, with focus on personality traits.

METHODS

Fifty seven patients (males 54.4%; age = 29.9 ± 6.0 yrs; age at the illness onset = 24.9 ± 5.1 yrs; IQ = 93.5 ± 12.2) were included. The assessment consisted of Nottingham Onset Schedule (NOS), Premorbid Adjustment Scale (PAS) and NEO Personality Inventory (NEO-PI-R). We used Cox regression model to evaluate relationship between DUP and explanatory variables.

RESULTS

Based on the most restrictive definition, the length of DUP in our sample was 77.8 ± 120.6 weeks (MED = 25.0 weeks). DUP was negatively associated with openness to experience (B = -0.804, P = 0.024).

CONCLUSIONS

We report the first evidence of DUP in Serbia, emphasizing that the personality domains are likely to impact the use of mental health care in persons with psychosis.

Cognitive neuropsychological functioning in New Zealand Māori diagnosed with schizophrenia

OBJECTIVE

Previous research suggests that New Zealand Māori may have an elevated rate of schizophrenia. However, there is limited evidence on important clinical features of the illness in this population. This study examined cognitive neuropsychological functioning in 54 adult Māori diagnosed with schizophrenia and 56 Māori controls. This study also examined associations between cognition, medication and symptoms of psychosis in the schizophrenia group.

METHOD

The groups were matched on socio-demographic variables, handedness and premorbid cognitive ability. Participants were assessed on neuropsychological tests of attention, executive ability, motor, premorbid ability, verbal/non-verbal memory and verbal fluency (English/Māori versions). The Positive and Negative Syndrome Scale was used to assess psychotic symptoms. Information on cultural identity, duration of illness, duration of untreated psychosis, medication and substance abuse was collected.

RESULTS

The performance of the schizophrenia group was significantly lower than the control group on all the neuropsychological tests, except the test of attention. The effect sizes were moderate to large: 0.78 for motor function; 1.3 for executive ability, verbal fluency and visual memory; 1.6 for verbal learning and 1.8 for verbal memory. These differences remained after adjustment for multiple comparisons and covariates. A higher dose of antipsychotic medication and a higher anticholinergic load were associated with greater verbal memory impairment (r = -0.38 and r = -0.38, respectively). A longer duration of illness was associated with greater impairment of verbal memory (rho = -0.48), verbal learning (rho = -0.41) and visual memory (rho = -0.44).

CONCLUSION

The findings for the schizophrenia group show a profile of generalised cognitive impairment with greater impairment of verbal memory. The cognitive impairment in this group was independent of psychotic symptoms, but was associated with a higher antipsychotic dose, higher anticholinergic load and longer duration of illness. These findings have implications for clinical prescribing practices and rehabilitation for New Zealand Māori diagnosed with schizophrenia.

The readmission rate and medical cost of patients with schizophrenia after first hospitalization - A 10-year follow-up population-based study

BACKGROUND

Hospital readmissions caused by relapse in patients with schizophrenia are associated with prognosis. Identifying individuals at high risk of readmission and providing interventions to lower the readmission rate are important.

METHODS

Patients with schizophrenia who were hospitalized for the first time were recruited from the National Health Insurance Research Database from 2001 to 2010 (n=808, mean age 28.9years) and compared with matched controls. Data on the demographics, cost, and utilization of medical resources of patients who were readmitted were compared with non-readmitted patients. The readmission time curve was analyzed by the Kaplan-Meier method.

RESULT

570 (70.5%) patients were readmitted within 10years; the median time between admissions was 1.9years, and 25% of subjects were readmitted within 4months of the first hospitalization. There were no significant differences in age, gender, or length of hospitalization between the readmission and non-readmission groups. Taking into account all psychiatric medical services, the readmission group had a significantly higher mean frequency of care and a greater medical cost than the non-readmission group and matched controls. However, there were no significant differences with regard to non-psychiatric medical services.

CONCLUSION

Schizophrenia has a high rate of readmission and high medical cost in naturalistic settings. In addition to the traditional hospital-based treatment model for patients with schizophrenia, the development of an effective intervention program is important, especially in the early years of the disease.

Neurocognition and Duration of Psychosis: A 10-year Follow-up of First-Episode Patients

A substantial proportion of schizophrenia-spectrum patients exhibit a cognitive impairment at illness onset. However, the long-term course of neurocognition and a possible neurotoxic effect of time spent in active psychosis, is a topic of controversy. Furthermore, it is of importance to find out what predicts the long-term course of neurocognition. Duration of untreated psychosis (DUP), accumulated time in psychosis the first year after start of treatment, relapse rates and symptoms are potential predictors of the long-term course. In this study, 261 first-episode psychosis patients were assessed neuropsychologically on one or more occasions. Patients were tested after remission of psychotic symptoms and reassessed 1, 2, 5, and 10 years after inclusion. The neurocognitive battery consisted of California Verbal Learning Test, Wisconsin Card Sorting Test, Controlled Oral Word Association Task, Trail Making A and B, and Finger Tapping. We calculated a composite score by adding the z-scores of 4 tests that were only moderately inter-correlated, not including Finger Tapping. Data were analyzed by a linear mixed model. The composite score was stable over 10 years. No significant relationship between psychosis before (DUP) or after start of treatment and the composite score was found, providing no support for the neurotoxicity hypothesis, and indicating that psychosis before start of treatment has no significant impact on the course and outcome in psychosis. We found no association between symptoms and the neurocognitive trajectory. Stable remission during the first year predicted neurocognitive functioning, suggesting that the early clinical course is a good predictor for the long-term course.

Poor premorbid school performance, but not severity of illness, predicts cognitive decline in schizophrenia in midlife

Neurocognitive dysfunction is common in schizophrenia but its course and determinants remain uncertain. Our aim was to analyse if premorbid school performance and the severity of illness and functioning predict change in cognition in schizophrenia in a general population sample. The sample included cases with schizophrenia spectrum disorder from the Northern Finland Birth Cohort 1966. Data on school marks at the age of 16 years, educational level at the age of 34 years, severity of symptoms and occupational functioning around first episode and after years of illness were gained from national registers, hospital notes and interviews. Change of verbal and visual learning and memory and executive functioning were examined between ages 34 and 43 years. The number of cases varied in analyses from 29 to 41, depending on missing data in particular cognitive tests. Lower school marks at age 16 years and lower education at age 34 years predicted more decline of cognition. Measures of severity of illness or functioning were not associated statistically significantly with change of cognition. Premorbid school performance, but not later course of schizophrenia, related to change of cognition in midlife. Poor premorbid scholastic performance and post-onset cognitive decline may represent related processes as part of an endophenotype of schizophrenia.