The prevalence and correlates of hallucinations in a general population sample: findings from the South African Stress and Health Study

Objective: Large epidemiological surveys conducted in the developed world have found rates of psychotic symptoms in the general population to be as high as 10-28%. However, there are few data available from developing countries, including African countries, on the prevalence and correlates of psychotic symptoms. This study investigates the prevalence and correlates of psychotic symptoms (ie hallucinations) in a general population sample of South African adults. Method: As part of the South African Stress and Health Study the prevalence of auditory and visual hallucinations was determined in a large community based sample of 4250 participants utilizing the Composite International Diagnostic Interview (CIDI). In addition, socio-demographic and clinical correlates as well as indicators of service utilization and functional impairment were determined. Results: The prevalence of any reported hallucination was 12.7%, a rate comparable to that found in studies from the developed world. Multivariate analyses revealed a significant association between role impairment, service utilisation, suicidality and reported auditory or visual hallucinations. No significant association was found between urbanicity and reported psychotic symptoms. Conclusion: Our finding that psychotic symptoms (ie hallucinations) are significantly associated with functional impairment and service utilization supports the potential clinical significance of such symptoms, even in the African context.Key Words: Prevalence; Psychosis; Population groups; Epidemiology; South Afric

Using a treatment partner and text messaging to improve adherence to psychotropic medication: A qualitative formative study of service users and caregivers in Cape Town, South Africa

Objective: Poor adherence to medications, including psychotropic medications contributes to the burden of disease. Mental health service users (MHSU) may also not attend follow-up appointments at their health care facilities where they could discuss adherence with their health care provider. This paper reports on preliminary qualitative research preceding a randomised controlled trial that aims to improve adherence to psychotropic medication and to follow up treatment visits. The intervention will entail the support of individuals with serious mental disorder by a treatment partner and short message service (SMS) text messaging. Methods: The preliminary research reported in this paper aimed to extract views about the intervention from both mental health service users (MHSU) and caregivers through focus group discussions and individual interviews. Data were analysed using ATLAS TI qualitative software.Results: The caregivers interviewed were all mothers of MHSU who took measures to encourage adherence. They held mixed opinions on whether the treatment partner should be a family member. Most participants expressed the view that due to living conditions, family members were natural treatment partners, but others stated that they would prefer a treatment partner who was not a family member. Similarly, while most MHSU supported the idea of a treatment partner, a minority were concerned that a treatment partner may potentially be too controlling and compromise their autonomy. The vast majority of participants supported SMS text messaging as a means of reminding MHSU to take their medication and attend followup appointments. One participant mentioned the importance of broader social inclusion issues that should be  incorporated in the intervention.Conclusion: Qualitative research may provide useful insights for the design of interventions of this nature related to social inclusion randomised control trials with its focus on adherence.Keywords: Mental illness; Treatment partner; Social inclusion; Community care; Mobile phone

The prevalence and correlates of hallucinations in a general population sample: findings from the South African Stress and Health Study

Objective: Large epidemiological surveys conducted in the developed world have found rates of psychotic symptoms in the general population to be as high as 10-28%. However, there are few data available from developing countries, including African countries, on the prevalence and correlates of psychotic symptoms. This study investigates the prevalence and correlates of psychotic symptoms (ie hallucinations) in a general population sample of South African adults. Method: As part of the South African Stress and Health Study the prevalence of auditory and visual hallucinations was determined in a large community based sample of 4250 participants utilizing the Composite International Diagnostic Interview (CIDI). In addition, socio-demographic and clinical correlates as well as indicators of service utilization and functional impairment were determined. Results: The prevalence of any reported hallucination was 12.7%, a rate comparable to that found in studies from the developed world. Multivariate analyses revealed a significant association between role impairment, service utilisation, suicidality and reported auditory or visual hallucinations. No significant association was found between urbanicity and reported psychotic symptoms. Conclusion: Our finding that psychotic symptoms (ie hallucinations) are significantly associated with functional impairment and service utilization supports the potential clinical significance of such symptoms, even in the African context

Monitoring the prevalence of methamphetamine-related presentations at psychiatric hospitals in Cape Town, South Africa

Objective: This study aimed to determine a demographic profile of methamphetamine (MA)-related admissions to major psychiatric services in Cape Town, obtain a substance use profile from admitted patients, a profile of common MA-related symptoms encountered during the assessment of the patients presenting with MA-related problems, and a brief profile of the psychiatric diagnoses made.Method: Staff in six psychiatric hospitals or wards in Cape Town collected data on methamphetamine related admissions between July and December 2008 using a one-page record review form. The data collection form consisted of the patient’s demographic details, presenting symptoms, previous admission details, current MA and other substance use information, and DSM-IV diagnosis. Results: A total of 235 forms were completed. Most patients were male (69%) and the mean age was 25 years. The most common presenting symptoms were aggressive behaviour (74%), followed by delusions (59%) and hallucinations (57%). Males were two times more likely to present with aggression as compared to females, while females were significantly more likely to present with depressed mood or euphoric/elevated mood. The majority of patients had substanceinduced psychotic disorder (41%), followed by schizophrenia (31%). Twelve percent (12%) had bipolar mood disorder.Conclusion: MA-related psychiatric admissions pose serious challenges to all health services dealing with these patients. Further training and treatment protocol development and distribution is indicated.Keywords: Methamphetamine; Admissions; Psychosis; South Afric

Reply to: New Meta- and Mega-analyses of Magnetic Resonance Imaging Findings in Schizophrenia: Do They Really Increase Our Knowledge About the Nature of the Disease Process?

This work was supported by National Institute of Biomedical Imaging and Bioengineering Grant No. U54EB020403 (to the ENIGMA consortium)

Increased power by harmonizing structural MRI site differences with the ComBat batch adjustment method in ENIGMA

A common limitation of neuroimaging studies is their small sample sizes. To overcome this hurdle, the Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium combines neuroimaging data from many institutions worldwide. However, this introduces heterogeneity due to different scanning devices and sequences. ENIGMA projects commonly address this heterogeneity with random-effects meta-analysis or mixed-effects mega-analysis. Here we tested whether the batch adjustment method, ComBat, can further reduce site-related heterogeneity and thus increase statistical power. We conducted random-effects meta-analyses, mixed-effects mega-analyses and ComBat mega-analyses to compare cortical thickness, surface area and subcortical volumes between 2897 individuals with a diagnosis of schizophrenia and 3141 healthy controls from 33 sites. Specifically, we compared the imaging data between individuals with schizophrenia and healthy controls, covarying for age and sex. The use of ComBat substantially increased the statistical significance of the findings as compared to random-effects meta-analyses. The findings were more similar when comparing ComBat with mixed-effects mega-analysis, although ComBat still slightly increased the statistical significance. ComBat also showed increased statistical power when we repeated the analyses with fewer sites. Results were nearly identical when we applied the ComBat harmonization separately for cortical thickness, cortical surface area and subcortical volumes. Therefore, we recommend applying the ComBat function to attenuate potential effects of site in ENIGMA projects and other multi-site structural imaging work. We provide easy-to-use functions in R that work even if imaging data are partially missing in some brain regions, and they can be trained with one data set and then applied to another (a requirement for some analyses such as machine learning)

Large-scale analysis of structural brain asymmetries in schizophrenia via the ENIGMA consortium

BACKGROUND Left-right asymmetry is an important organizing feature of the healthy brain that may be altered in schizophrenia, but most studies have used relatively small samples and heterogeneous approaches, resulting in equivocal findings. We carried out the largest case-control study of structural brain asymmetries in schizophrenia (N = 11,095), using a single image analysis protocol. METHODS We included T1-weighted data from 46 datasets (5,080 affected individuals and 6,015 controls) from the ENIGMA Consortium. Asymmetry indexes were calculated for global and regional cortical thickness, surface area, and subcortical volume measures. Differences of asymmetry were calculated between affected individuals and controls per dataset, and effect sizes were meta-analyzed across datasets. Analyses were also performed with respect to the use of antipsychotic medication and other clinical variables, as well as age and sex. Case-control differences in a multivariate context were assessed in a subset of the data (N = 2,029). RESULTS Small average differences between cases and controls were observed for asymmetries in cortical thickness, specifically of the rostral anterior cingulate (d = −0.08, pFDR = 0.047) and the middle temporal gyrus (d = −0.07, pFDR = 0.048), both driven primarily by thinner cortices in the left hemisphere in schizophrenia. These asymmetries were not significantly associated with the use of antipsychotic medication or other clinical variables. Older individuals with schizophrenia showed a stronger average leftward asymmetry of pallidum volume than older controls (d = 0.08, pFDR = 9.0 × 10−3). The multivariate analysis revealed that 7% of the variance across all structural asymmetries was explained by case-control status (F = 1.87, p = 1.25 × 10−5). CONCLUSIONS Altered trajectories of asymmetrical brain development and/or lifespan asymmetry may contribute to schizophrenia pathophysiology. Small case-control differences of brain macro-structural asymmetry may manifest due to more substantial differences at the molecular, cytoarchitectonic or circuit levels, with functional relevance for lateralized cognitive processes

Subcortical volumes across the lifespan: Data from 18,605 healthy individuals aged 3–90 years

Age has a major effect on brain volume. However, the normative studies available are constrained by small sample sizes, restricted age coverage and significant methodological variability. These limitations introduce inconsistencies and may obscure or distort the lifespan trajectories of brain morphometry. In response, we capitalized on the resources of the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) Consortium to examine age‐related trajectories inferred from cross‐sectional measures of the ventricles, the basal ganglia (caudate, putamen, pallidum, and nucleus accumbens), the thalamus, hippocampus and amygdala using magnetic resonance imaging data obtained from 18,605 individuals aged 3–90 years. All subcortical structure volumes were at their maximum value early in life. The volume of the basal ganglia showed a monotonic negative association with age thereafter; there was no significant association between age and the volumes of the thalamus, amygdala and the hippocampus (with some degree of decline in thalamus) until the sixth decade of life after which they also showed a steep negative association with age. The lateral ventricles showed continuous enlargement throughout the lifespan. Age was positively associated with inter‐individual variability in the hippocampus and amygdala and the lateral ventricles. These results were robust to potential confounders and could be used to examine the functional significance of deviations from typical age‐related morphometric patterns