Classification of first-episode psychosis using cortical thickness: A large multicenter MRI study.

Machine learning classifications of first-episode psychosis (FEP) using neuroimaging have predominantly analyzed brain volumes. Some studies examined cortical thickness, but most of them have used parcellation approaches with data from single sites, which limits claims of generalizability. To address these limitations, we conducted a large-scale, multi-site analysis of cortical thickness comparing parcellations and vertex-wise approaches. By leveraging the multi-site nature of the study, we further investigated how different demographical and site-dependent variables affected predictions. Finally, we assessed relationships between predictions and clinical variables. 428 subjects (147 females, mean age 27.14) with FEP and 448 (230 females, mean age 27.06) healthy controls were enrolled in 8 centers by the ClassiFEP group. All subjects underwent a structural MRI and were clinically assessed. Cortical thickness parcellation (68 areas) and full cortical maps (20,484 vertices) were extracted. Linear Support Vector Machine was used for classification within a repeated nested cross-validation framework. Vertex-wise thickness maps outperformed parcellation-based methods with a balanced accuracy of 66.2% and an Area Under the Curve of 72%. By stratifying our sample for MRI scanner, we increased generalizability across sites. Temporal brain areas resulted as the most influential in the classification. The predictive decision scores significantly correlated with age at onset, duration of treatment, and positive symptoms. In conclusion, although far from the threshold of clinical relevance, temporal cortical thickness proved to classify between FEP subjects and healthy individuals. The assessment of site-dependent variables permitted an increase in the across-site generalizability, thus attempting to address an important machine learning limitation.

Basic symptoms in young people at ultra-high risk of psychosis: Association with clinical characteristics and outcomes.

There has been limited research into the predictive value of basic symptoms and their relationship with other psychopathology in patients identified using the 'ultra high risk' (UHR) for psychosis approach. The current study investigated whether basic symptoms, specifically cognitive disturbances (COGDIS), were associated with a greater risk of transition to psychotic disorder and persistent attenuated psychotic symptoms (APS) at medium term follow-up (mean = 3.4 years) in UHR patients, as well as with general psychopathology at baseline. The sample included 304 UHR participants (mean age = 19.12 years) involved in an international multicenter trial of omega-3 fatty acids. UHR individuals who also met the COGDIS criteria (basic symptoms risk criteria) did not have a greater risk of transition than those who met the UHR criteria alone. However, meeting COGDIS risk criteria was associated with a greater likelihood of meeting the UHR attenuated psychotic symptoms risk group (i.e., having persistent attenuated psychotic symptoms) at 12-month follow-up (odds ratio = 1.85; 95% CI = 1.03, 3.32). Greater severity of cognitive basic symptoms was also independently associated with more severe general psychopathology at study entry. The findings do not support the notion that combined risk identification approaches (UHR and basic symptoms) aid in the identification of individuals at greatest risk of psychosis, although this interpretation is limited by the modest transition to psychosis rate (13%) and the time of follow up. However, the findings indicate that basic symptoms may be a clinically useful marker of more severe general psychopathology in UHR groups and risk for persistent attenuated psychotic symptoms.

Dynamic prediction of transition to psychosis using joint modelling.

Considerable research has been conducted seeking risk factors and constructing prediction models for transition to psychosis in individuals at ultra-high risk (UHR). Nearly all such research has only employed baseline predictors, i.e. data collected at the baseline time point, even though longitudinal data on relevant measures such as psychopathology have often been collected at various time points. Dynamic prediction, which is the updating of prediction at a post-baseline assessment using baseline and longitudinal data accumulated up to that assessment, has not been utilized in the UHR context. This study explored the use of dynamic prediction and determined if it could enhance the prediction of frank psychosis onset in UHR individuals. An emerging statistical methodology called joint modelling was used to implement the dynamic prediction. Data from the NEURAPRO study (n = 304 UHR individuals), an intervention study with transition to psychosis study as the primary outcome, were used to investigate dynamic predictors. Compared with the conventional approach of using only baseline predictors, dynamic prediction using joint modelling showed significantly better sensitivity, specificity and likelihood ratios. As dynamic prediction can provide an up-to-date prediction for each individual at each new assessment post entry, it can be a useful tool to help clinicians adjust their prognostic judgements based on the unfolding clinical symptomatology of the patients. This study has shown that a dynamic approach to psychosis prediction using joint modelling has the potential to aid clinicians in making decisions about the provision of timely and personalized treatment to patients concerned.

NEURAPRO: a multi-centre RCT of omega-3 polyunsaturated fatty acids versus placebo in young people at ultra-high risk of psychotic disorders-medium-term follow-up and clinical course.

This study reports a medium-term follow-up of a randomised, double-blind, placebo-controlled trial of omega-3 polyunsaturated fatty acids (PUFA) in ultra-high risk for psychosis (UHR) patients. Primary outcomes of interest were transition to psychosis and symptomatic and functional outcome. A secondary aim was to investigate clinical predictors of medium-term outcome. Three hundred four UHR participants were recruited across 10 specialised early psychosis services in Australia, Asia, and Europe. The intervention consisted of 1.4 g/daily of omega-3 PUFA or placebo, plus up to 20 sessions of cognitive-behavioural case management (CBCM), over the 6-month study period, with participants receiving further CBCM sessions on basis of need between months 6-12. Mean time to follow-up was 3.4 (median = 3.3; SD = 0.9) years. There was a modest increase in transitions between 12-month and medium-term follow-up (11-13%) and substantial improvement in symptoms and functioning between baseline and follow-up, with no differences between the treatment groups. Most improvement had been achieved by end of the intervention. 55% of the sample received mental health treatment between end of intervention and follow-up. Omega-3 PUFA did not provide additional benefits to good quality psychosocial intervention over the medium term. Although most improvement had been achieved by end of intervention the substantial rates of post-intervention mental health service use indicate longer-term clinical need in UHR patients. The post-intervention phase treatment or the longer-term effect of CBCM, or a combination of the two, may have contributed to maintaining the gains achieved during the intervention phase and prevented significant deterioration after this time.

Disturbed glutathione antioxidative defense is associated with structural brain changes in neuroleptic-naïve first-episode psychosis patients.

BACKGROUND: Oxidative stress and impaired antioxidant defense are reported in schizophrenia and are thought to be associated with disturbed neurodevelopment, brain structural alterations, glutamatergic imbalance, negative symptomatology, and cognitive impairment. To test some of these assumptions we investigated the glutathione (GSH) antioxidant defense system (AODS) and brain structural abnormalities in drug-naïve individuals with first acute episode of psychosis (FEP). METHOD: The study involved 27 drug-naïve FEP patients and 31 healthy controls (HC). GSH AODS markers and TBARS (thiobarbituric acid reactive substances) were measured in blood plasma and erythrocytes. High-resolution T1-weighted 3T MRI were acquired from all subjects. To investigate brain structural abnormalities and effects of illness on interactions between GSH metabolites or enzyme activities and local grey matter density, voxel-based morphometry (VBM) with the computational anatomy toolbox (CAT12) was used. Symptomatology was assessed using the Positive and Negative Syndrome Scale (PANSS) and the Symptom Checklist 1990 revised (SCL-90-R). RESULTS: (i) In FEP patients, glutathione reductase activity (GSR) was lower than in the HC group. GSR activity in plasma was inversely correlated with SCL-90-R scores of depression and PANSS scores of the negative symptom subscale. (ii) A reduction of GM was observed in left inferior frontal, bilateral temporal, as well as parietal cortices of FEP patients. (iii) Interaction analyses revealed an influence of illness on GSR/GM associations in the left orbitofrontal cortex (BA 47). CONCLUSION: Our findings support the notion of altered GSH antioxidative defense in untreated acute psychosis as a potential pathomechanism for localized brain structural abnormalities. This pathology relates to a key brain region of social cognition, affective motivation control and decision making, and is clinically accompanied by depressive and negative symptoms.

The Ultra-High-Risk for psychosis groups: Evidence to maintain the status quo.

Individuals are considered Ultra-High-Risk (UHR) for psychosis if they meet a set of standardised criteria including presumed genetic vulnerability (Trait), or a recent history of Attenuated Psychotic Symptoms (APS) or Brief Limited Intermittent Psychotic Symptoms (BLIPS). Recent calls to revise these criteria have arisen from evidence that Trait, APS and BLIPS groups may transition to psychosis at different rates. Concurrently, it has become clear that the UHR status confers clinical risk beyond transition to psychosis. Specifically, most UHR individuals will not develop psychosis, but will experience high rates of non-psychotic disorders, persistent APS and poor long-term functional outcomes. Rather than focus on transition, the present study investigated whether UHR groups differ in their broader clinical risk profile by examining baseline clinical characteristics and long-term outcomes other than transition to psychosis. Four UHR groups were defined: Trait-only, APS-only, Trait+APS, and any BLIPS. Participants (N=702) were recruited upon entry to early intervention services and followed-up over a period of up to 13years (mean=4.53, SD=3.84). The groups evidenced similar symptom severity (SANS for negative symptoms, BPRS for positive and depression/anxiety symptoms) and psychosocial functioning (SOFAS, GAF, QLS) at baseline and follow-up as well as similar prevalence of non-psychotic disorders at follow-up. Our findings demonstrate that UHR groups evidence a similar clinical risk profile when we expand this beyond transition to psychosis, and consequently support maintaining the existing UHR criteria.

Omega-6 to omega-3 polyunsaturated fatty acid ratio and subsequent mood disorders in young people with at-risk mental states: a 7-year longitudinal study.

While cross-sectional studies suggest that patients with mood disorders have a higher ratio of omega-6 to omega-3 polyunsaturated fatty acids (PUFAs) and lower levels of omega-3 PUFAs, it is unknown if a high n-6/3 ratio indicates vulnerability for depression. We tested this hypothesis in a 7-year follow-up study of young individuals with an ultra-high risk (UHR) phenotype. We conducted a secondary analysis of the Vienna omega-3 study, a longitudinal study of omega-3 PUFAs in individuals at UHR for psychosis (n=69). Levels of n-6 and n-3 PUFAs were measured in the phosphatidylethanolamine fraction of erythrocyte membranes at intake into the study. Mood disorder diagnosis was ascertained with the Structured Clinical Interview for DSM-IV-TR and confirmed by review of medical records and interviews of caregivers. A higher n-6/3 PUFA ratio at baseline predicted mood disorders in UHR individuals over a 7-year (median) follow-up (odds ratio=1.89, 95% CI=1.075-3.338, P=0.03). This association remained significant after adjustment for age, gender, smoking, severity of depressive symptoms at baseline and n-3 supplementation. Consistent results were obtained for individual PUFAs, including lower levels of eicosapentaenoic acid and docosahexaenoic acid. The predictive capacity of these findings was specific to mood disorders as no associations were found for any other psychiatric disorder. To our knowledge, our data provide the first prospective evidence that the n-6/3 PUFA ratio is associated with an increased risk for mood disorders in young people exhibiting an UHR phenotype. These findings may have important implications for treatment and risk stratification beyond clinical characteristics.

Erythrocyte glutathione levels as long-term predictor of transition to psychosis.

A high proportion of individuals deemed at elevated risk for psychosis will actually never progress to develop the illness. Pharmaceutical intervention may not be necessary in these cases, and may in fact be damaging depending on the invasiveness of the treatment strategy. This highlights the need for biomarkers that are better able to reliably differentiate between at-risk individuals who will subsequently transition to psychosis and those who will not. Low glutathione (GSH) levels have been observed in schizophrenia and in patients with first-episode psychosis. The aim of this study was to determine the predictive value of erythrocyte GSH levels on the transition to psychosis in individuals at risk of developing the illness. Erythrocyte GSH levels were measured in 36 at-risk individuals, 15 of whom had transitioned to psychosis at the 7-year follow-up. Univariate Cox regression analysis showed that transition to psychosis at the 7-year time point was significantly associated with low GSH levels at baseline. The area under the receiving operating characteristic curve was 0.819, indicating that GSH can be considered a good predictor of outcome. Although these results need to be replicated, adding the criterion 'low erythrocyte GSH' to the set of criteria used to identify individuals at risk of psychosis may be indicated.

Prediction of transition from ultra-high risk to first-episode psychosis using a probabilistic model combining history, clinical assessment and fatty-acid biomarkers.

Current criteria identifying patients with ultra-high risk of psychosis (UHR) have low specificity, and less than one-third of UHR cases experience transition to psychosis within 3 years of initial assessment. We explored whether a Bayesian probabilistic multimodal model, combining baseline historical and clinical risk factors with biomarkers (oxidative stress, cell membrane fatty acids, resting quantitative electroencephalography (qEEG)), could improve this specificity. We analyzed data of a UHR cohort (n=40) with a 1-year transition rate of 28%. Positive and negative likelihood ratios were calculated for predictor variables with statistically significant receiver operating characteristic curves (ROCs), which excluded oxidative stress markers and qEEG parameters as significant predictors of transition. We clustered significant variables into historical (history of drug use), clinical (Positive and Negative Symptoms Scale positive, negative and general scores and Global Assessment of Function) and biomarker (total omega-3, nervonic acid) groups, and calculated the post-test probability of transition for each group and for group combinations using the odds ratio form of Bayes' rule. Combination of the three variable groups vastly improved the specificity of prediction (area under ROC=0.919, sensitivity=72.73%, specificity=96.43%). In this sample, our model identified over 70% of UHR patients who transitioned within 1 year, compared with 28% identified by standard UHR criteria. The model classified 77% of cases as very high or low risk (P>0.9, <0.1) based on history and clinical assessment, suggesting that a staged approach could be most efficient, reserving fatty-acid markers for 23% of cases remaining at intermediate probability following bedside interview.

ZNF804A genetic variation (rs1344706) affects brain grey but not white matter in schizophrenia and healthy subjects.

BACKGROUND: Genetic variation in the gene encoding ZNF804A, a risk gene for schizophrenia, has been shown to affect brain functional endophenotypes of the disorder, while studies of white matter structure have been inconclusive. METHOD: We analysed effects of ZNF804A single nucleotide polymorphism rs1344706 on grey and white matter using voxel-based morphometry (VBM) in high-resolution T1-weighted magnetic resonance imaging scans of 62 schizophrenia patients and 54 matched healthy controls. RESULTS: We found a significant (p < 0.05, family-wise error corrected for multiple comparisons) interaction effect of diagnostic group x genotype for local grey matter in the left orbitofrontal and right and left lateral temporal cortices, where patients and controls showed diverging effects of genotype. Analysing the groups separately (at p < 0.001, uncorrected), variation in rs1344706 showed effects on brain structure within the schizophrenia patients in several areas including the left and right inferior temporal, right supramarginal/superior temporal, right and left inferior frontal, left frontopolar, right and left dorsolateral/ventrolateral prefrontal cortices, and the right thalamus, as well as effects within the healthy controls in left lateral temporal, right anterior insula and left orbitofrontal cortical areas. We did not find effects of genotype of regional white matter in either of the two cohorts. CONCLUSIONS: Our findings demonstrate effects of ZNF804A genetic variation on brain structure, with diverging regional effects in schizophrenia patients and healthy controls in frontal and temporal brain areas. These effects, however, might be dependent on the impact of other (genetic or non-genetic) disease factors.

Omega-3 fatty acid supplementation changes intracellular phospholipase A2 activity and membrane fatty acid profiles in individuals at ultra-high risk for psychosis.

The identification of an ultra-high risk (UHR) profile for psychosis and a greater understanding of its prodrome have led to increasing interest in early intervention to delay or prevent the onset of psychotic illness. In a randomized placebo-controlled trial, we have identified long-chain ω-3 (ω-3) polyunsaturated fatty acid (PUFA) supplementation as potentially useful, as it reduced the rate of transition to psychosis by 22.6% 1 year after baseline in a cohort of 81 young people at UHR of transition to psychosis. However, the mechanisms whereby the ω-3 PUFAs might be neuroprotective are incompletely understood. Here, we report on the effects of ω-3 PUFA supplementation on intracellular phospholipase A2 (inPLA(2)) activity, the main enzymes regulating phospholipid metabolism, as well as on peripheral membrane lipid profiles in the individuals who participated in this randomized placebo-controlled trial. Patients were studied cross-sectionally (n=80) and longitudinally (n=65) before and after a 12-week intervention with 1.2 g per day ω-3 PUFAs or placebo, followed by a 40-week observation period to establish the rates of transition to psychosis. We investigated inPLA(2) and erythrocyte membrane FAs in the treatment groups (ω-3 PUFAs vs placebo) and the outcome groups (psychotic vs non-psychotic). The levels of membrane ω-3 and ω-6 PUFAs and inPLA(2) were significantly related. Some of the significant associations (that is, long-chain ω-6 PUFAs, arachidonic acid) with inPLA(2) activity were in opposite directions in individuals who did (a positive correlation) and who did not (a negative correlation) transition to psychosis. Supplementation with ω-3 PUFA resulted in a significant decrease in inPLA(2) activity. We conclude that ω-3 PUFA supplementation may act by normalizing inPLA(2) activity and δ-6-desaturase-mediated metabolism of ω-3 and ω-6 PUFAs, suggesting their role in neuroprogression of psychosis.

Impaired niacin sensitivity in acute first-episode but not in multi-episode schizophrenia.

Niacin (vitamin B3) flushing--a marker of altered prostaglandin signaling--is indirectly linked to the phospholipid-prostaglandin metabolism. Diminished skin flushing was repeatedly found in schizophrenia, but has not been systematically investigated at different stages of disorder as yet. We compared niacin sensitivity of 32 first-episode and 32 multi-episode patients (mainly on stable medication) with age and gender matched healthy controls. Methylnicotinate was applied in three concentrations onto the inner forearm skin. Flush response was assessed in 3 min intervals over 15 min using optical reflection spectroscopy. Whereas first-episode patients showed significantly diminished flush response as compared to controls, comparable differences were not found between multi-episode patients and controls. Comparison of niacin sensitivity at different stages of schizophrenia support the notion of altered prostaglandin signaling primarily at the onset of disorder. Longitudinal studies have to rule out possible long-term effects of neuroleptic medication.

[Quantitative measurement of induced skin reddening using optical reflection spectroscopy--methodology and clinical application]. / Quantitative Messung induzierter Hautrötungen durch optische Reflexionsspektroskopie--Methodik und klinische Anwendung.

Optical reflection spectroscopy is a simple and quick method for the quantification of colour intensity, and is thus suitable for the determination of changes in skin reddening (erythema) due to local vasodilatation. To quantify the time course of this erythema, the oxyhaemoglobin absorption double peak with maxima at 542 and 577 nm is an appropriate parameter. A compact handheld optical spectrometer makes the technique applicable to clinical use, an example being the niacin patch test described herein. This noninvasive test provides information about the cell membrane metabolism via the skin flush induced by niacin (vitamin B3) and mediated by prostaglandin. The aim of this study was to adapt optical reflection spectroscopy to the requirements of the clinical niacin patch test. To that end, we investigated 60 healthy volunteers. Analysis of the spectroscopic data with regard to physiological covariables of niacin sensitivity revealed faster and more intense erythema in females--a gender effect that to our knowledge has not previously been reported. In the light of these results, the findings of other researchers based on semi-quantitative test methods should be reassessed, with consideration given to the gender effect.

[Repetitive transcranial magnetic stimulation (rTMS) in the acute and long-term therapy of refractory depression--a case report]. / Repetitive transkranielle Magnetstimulation (rTMS) in der Akut- und Langzeittherapie bei therapieresistenter Depression. Eine Falldarstellung.

We report on a patient with therapy-resistant major depression according to DSM-IV criteria who has been hospitalized for 60 months during the last 7 years. Not even five electroconvulsive therapy (ECT) series (61 single applications) brought lasting remission of symptoms. As cognitive deficits developed and prolonged postnarcotic recovery times were observed, further ECT was contraindicated. The left frontal cortex was chosen as the target site for repetitive transcranial magnetic stimulation (rTMS) treatment. For identification, a neuronavigational system was used that allows online monitoring of the position of the magnetic coil in relation to the individual cortex. The therapeutic progress was monitored by standardized psychiatric ratings (HAMD, BDI). In addition, cognitive performance was tested during the course of treatment. Only a few rTMS applications already caused an obvious brightening in mood, remission of depressive delusional symptoms, and an increase in personal interests and activities. After 4 weeks of daily treatment, the patient was discharged from the ward. The rTMS treatments and psychotherapeutic counseling have been continued on an outpatient basis. Thus, pharmaco- and psychotherapeutic interventions combined with rTMS led to persistent symptom remission and social reintegration.

Hypofrontality in neuroleptic-naive schizophrenic patients during the Wisconsin Card Sorting Test--a fMRI study.

Functional neuroimaging findings of "hypofrontality" in schizophrenic patients - as tested with the Wisconsin Card Sorting Test (WCST) - are still controversial, mainly due to methodological aspects and the heterogeneity of the patient samples. To measure WCST specific and reproducible reduced cerebral activations in schizophrenic patients, we revised the study design and patient recruitment, respectively. For this purpose, we used an adequate active control task instead of an undefined rest condition to determine exclusively WCST specific cerebral activations. In addition, we focused on the investigation of modified activations between a selected group of neuroleptic-naive schizophrenic patients and carefully matched healthy controls by means of functional magnetic resonance imaging. The results indicate that neuroleptic-naive schizophrenic patients show reduced activations in the right frontal and left temporal lobe, as well as in the left cerebellum. By utilizing an active control task all unwanted activations are suppressed. Furthermore the influence of different task performances is reduced. The findings are in line with previous PET and SPECT studies and confirm the "hypofrontality" hypothesis. The findings suggest that "hypofrontality" is not caused by neuroleptic medication.

[Modern follow-up strategies for the treatment of patients with superficial bladder carcinoma]. / Moderne Nachsorgestrategien beim oberflächlichen Harnblasenkarzinom.

In this retrospective study the efficacy of tumor dispensaire in patients with superficial transitional cell carcinoma of the bladder was investigated in a population of 246 patients. Special attention was payed to follow up cystoscopy. Furthermore our goal was to identify and confirm prognostic factors relevant to recurrence rate and tumor progression. After transurethral resection 241 patients suffering from superficial bladder cancer were enclosed. The first of them were diagnosed in 1984 with a mean follow up range of 6.1 years and a minimum of 1 year. The evaluation was closed in 1995. The 1-year recurrence free rate of all cases amounts to 60%, whereas 42% of patients with a pT1-primary tumor and 45% with a pTa-primum developed a relapse within 2 years after the first diagnosis. All in all more than 50% of all recurrent tumors occurred within the first two years if illness. Patients with pTa and pT1 tumor are progressed in 10.7% and 18%. In 8% we saw lymphogen metastases in patients with pT1 carcinoma. 149 patients (62%) were followed up exactly (+/- 1 cystoscopy) according to the investigation schedule. More than +/- 3 aberrant cystoscopies contrary to the follow up instructions happened very seldom. Prognostic factors to be found of significance for tumor progression and recurrence risk are: tumor staging and grading, multiplicity in occurrence, period of time between first diagnosis and first relapse, associated dysplasia or carcinoma in situ. Chest X-ray and urography should be performed in accordance to the patients individual clinical situation, not routinely (2 cases of pulmonary metastasis occurred after pT1G2-3 tumor progression in 496 regular chest X-rays and 1 ureter tumor was diagnosed by routine urography). As a main result of our investigation we defined two groups of patients with superficial bladder cancer: a "low risk" group (pTa, G1-2, late recurrence (> 2 yrs.) and a "high risk" group (pT1, G3, early recurrence (< 2 yrs.), multifocal occurrence). Group 1 ("low risk") should be followed up for 5 years and group 2 ("high risk") for 10 years. Cystoscopic investigations are scheduled with regard to the group risk of recurrence and tumor progression. For patients of both groups the need of chest X-ray and urography should be evaluated individually.

[Diseases of phospholipid metabolism as possible pathogenetic factors in schizophrenia. Current findings and critical evaluation]. / Störungen im Phospholipidmetabolismus als mögliche pathogenetische Faktoren der Schizophrenie. Zusammenfassung aktueller Befunde und kritische Würdigung.

During the last few years analyses of the lipidmetabolism have been performed on schizophrenic patients. Anabolic and katabolic metabolite-concentrations from blood and cell samples have been measured. By means of new investigation techniques, such as 31P-magnetic-resonance-spectroscopy, it is nowadays even possible to determine membrane metabolites non-invasively in vivo. Arachidonic acid deficits in peripheral cell membranes, turnover of phosphodiesters in the brain, increased phospholipase A2 (PLA2)-activity in serum and blood cells, disturbed niacin-response and abnormalities of the PLA2-gene are summarised as phospholipid-membrane-hypothesis of schizophrenia. Although there is some evidence for correlations between those findings and psychotic symptoms, the connection to the pathogenesis of schizophrenia still has speculative character. Furthermore it has to be confirmed that peripheral biochemical findings acquired in schizophrenics are transferable to the metabolism of the central nervous system. Actual results of enzyme and metabolite measurements reported in literature and current findings of our own 31P-MR-spectroscopic studies are surveyed and summarised. To point out possible connections between the phospholipid-metabolism of the central nervous system and of peripheral blood-cells, systemic approaches are considered.

Reduced phosphodiesters and high-energy phosphates in the frontal lobe of schizophrenic patients: a (31)P chemical shift spectroscopic-imaging study.

BACKGROUND: (31)Phosphorous magnetic resonance spectroscopy has been widely used to evaluate schizophrenic patients in comparison to control subjects, because it allows the investigation of both phospholipid and energy metabolism in vivo; however, the results achieved so far are inconsistent. Chemical shift imaging (CSI) has the advantage that instead of only one or a few preselected voxels the tissue of a whole brain slice can be examined. The aim of the present investigation was to determine whether the results of previous studies of our group, showing that phosphodiesters (PDE) are decreased in the frontal lobe of schizophrenic patients as compared to control subjects, might be confirmed in an independent unmedicated patient sample using the CSI technique. METHODS: A carefully selected new cohort including 11 neuroleptic-free schizophrenic patients and 11 age- and gender-matched healthy control subjects was recruited. CSI was applied and an innovative analysis method for CSI data based on a general linear model was used. RESULTS: PDE, phosphocreatine, and adenosine triphosphate (ATP) were found to be significantly decreased in the frontal lobe of patients with schizophrenia. CONCLUSIONS: Because PDE was decreased in schizophrenic patients, the membrane phospholipid hypothesis of schizophrenia could not be corroborated. Further results indicate decreased ATP production in the frontal lobe of patients with schizophrenia.