Is familiality associated with downward occupation drift in schizophrenia?

Adjunctive yoga training for persons with schizophrenia: who benefits?

OBJECTIVE

The aim of this study was to identify factors associated with acceptability and efficacy of yoga training (YT) for improving cognitive dysfunction in individuals with schizophrenia (SZ).

METHODS

We analysed data from two published clinical trials of YT for cognitive dysfunction among Indians with SZ: (1) a 21-day randomised controlled trial (RCT, N = 286), 3 and 6 months follow-up and (2) a 21-day open trial (n = 62). Multivariate analyses were conducted to examine the association of baseline characteristics (age, sex, socio-economic status, educational status, duration, and severity of illness) with improvement in cognition (i.e. attention and face memory) following YT. Factors associated with acceptability were identified by comparing baseline demographic variables between screened and enrolled participants as well as completers versus non-completers.

RESULTS

Enrolled participants were younger than screened persons who declined participation (t = 2.952, p = 0.003). No other characteristics were associated with study enrollment or completion. Regarding efficacy, schooling duration was nominally associated with greater and sustained cognitive improvement on a measure of facial memory. No other baseline characteristics were associated with efficacy of YT in the open trial, the RCT, or the combined samples (n = 148).

CONCLUSIONS

YT is acceptable even among younger individuals with SZ. It also enhances specific cognitive functions, regardless of individual differences in selected psychosocial characteristics. Thus, yoga could be incorporated as adjunctive therapy for patients with SZ. Importantly, our results suggest cognitive dysfunction is remediable in persons with SZ across the age spectrum.

Stratifying empiric risk of schizophrenia among first degree relatives using multiple predictors in two independent Indian samples

BACKGROUND

Schizophrenia (SZ) has an estimated heritability of 64-88%, with the higher values based on twin studies. Conventionally, family history of psychosis is the best individual-level predictor of risk, but reliable risk estimates are unavailable for Indian populations. Genetic, environmental, and epigenetic factors are equally important and should be considered when predicting risk in 'at risk' individuals.

OBJECTIVE

To estimate risk based on an Indian schizophrenia participant's family history combined with selected demographic factors.

METHODS

To incorporate variables in addition to family history, and to stratify risk, we constructed a regression equation that included demographic variables in addition to family history. The equation was tested in two independent Indian samples: (i) an initial sample of SZ participants (N=128) with one sibling or offspring; (ii) a second, independent sample consisting of multiply affected families (N=138 families, with two or more sibs/offspring affected with SZ).

RESULTS

The overall estimated risk was 4.31±0.27 (mean±standard deviation). There were 19 (14.8%) individuals in the high risk group, 75 (58.6%) in the moderate risk and 34 (26.6%) in the above average risk (in Sample A). In the validation sample, risks were distributed as: high (45%), moderate (38%) and above average (17%). Consistent risk estimates were obtained from both samples using the regression equation.

CONCLUSIONS

Familial risk can be combined with demographic factors to estimate risk for SZ in India. If replicated, the proposed stratification of risk may be easier and more realistic for family members.

Association study of neuregulin-1 gene polymorphisms in a North Indian schizophrenia sample

BACKGROUND

Neuregulin-1 (NRG1) gene polymorphisms have been proposed as risk factors for several common disorders. Associations with cognitive variation have also been tested. With regard to schizophrenia (SZ) risk, studies of Caucasian ancestry samples indicate associations more consistently than East Asian samples, suggesting heterogeneity. To exploit the differences in linkage disequilibrium (LD) structure across ethnic groups, we conducted a SZ case-control study (that included cognitive evaluations) in a sample from the north Indian population.

METHODS

NRG1 variants (n=35 SNPs, three microsatellite markers) were initially analyzed among cases (DSM IV criteria, n=1007) and controls (n=1019, drawn from two groups) who were drawn from the same geographical region in North India. Nominally significant associations with SZ were next analyzed in relation to neurocognitive measures estimated with a computerized neurocognitive battery in a subset of the sample (n=116 cases, n=170 controls).

RESULTS

Three variants and one microsatellite showed allelic association with SZ (rs35753505, rs4733263, rs6994992, and microsatellite 420M9-1395, p≤0.05 uncorrected for multiple comparisons). A six marker haplotype 221121 (rs35753505-rs6994992-rs1354336-rs10093107-rs3924999-rs11780123) showed (p=0.0004) association after Bonferroni corrections. Regression analyses with the neurocognitive measures showed nominal (uncorrected) associations with emotion processing and attention at rs35753505 and rs6994992, respectively.

CONCLUSIONS

Suggestive associations with SZ and SZ-related neurocognitive measures were detected with two SNPs from the NRG1 promoter region in a north Indian cohort. The functional role of the alleles merits further investigation.

Predictive value of thought disorder in new-onset psychosis

OBJECTIVE

This research addresses the relationship of formal thought disorder in the early stages of psychotic illness to the long-term outcome of mental health many years later. The specific topic of concern was to evaluate the prognostic significance of thought disorder on the severity of psychosis over time.

METHODS

Subjects with new-onset psychosis were evaluated on a variety of measures including education, physical health, Brief Psychiatric Rating Scale scores. They were also given the Thought, Language, and Communication Scale to evaluate thought disorder. Subjects were interviewed again at 10 and 20 years to evaluate variations in outcome. Appropriate statistical methods were used to evaluate changes in the level of functioning over time.

RESULTS

Thought disorder was not unique to schizophrenia. Bipolar patients presented with significant positive thought disorder at the onset of psychosis. Overtime positive thought disorder gradually improved in most patients. Negative thought disorder was more persistent, especially in subjects with schizophrenia. Initial psychosis with thought disorder characterized by poverty of content seemed to be associated with poor long-term outcome.

CONCLUSION

Formal thought disorder can predict outcome in some cases of psychosis. Not all types of thought disorder have the same prognostic implication. Positive forms of thought disorder (pressured speech, tangentiality) had no significant predictive value. Negative thought disorder (particularly poverty of speech and poverty of content) tend to predict a chronic, more unrelenting course of illness.