Cognition in older age bipolar disorder: An analysis of archival data across the globe

BACKGROUND

Cognitive deficits in bipolar disorder (BD) impact functioning and are main contributors to disability in older age BD (OABD). We investigated the difference between OABD and age-comparable healthy comparison (HC) participants and, among those with BD, the associations between age, global cognitive performance, symptom severity and functioning using a large, cross-sectional, archival dataset harmonized from 7 international OABD studies.

METHODS

Data from the Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) database, spanning various standardized measures of cognition, functioning and clinical characteristics, were analyzed. The sample included 662 euthymic to mildly symptomatic participants aged minimum 50years (509 BD, 153 HC), able to undergo extensive cognitive testing. Linear mixed models estimated associations between diagnosis and global cognitive performance (g-score, harmonized across studies), and within OABD between g-score and severity of mania and depressive symptoms, duration of illness and lithium use and of global functioning.

RESULTS

After adjustment for study cohort, age, gender and employment status, there was no significant difference in g-score between OABD and HC, while a significant interaction emerged between employment status and diagnostic group (better global cognition associated with working) in BD. Within OABD, better g-scores were associated with fewer manic symptoms, higher education and better functioning.

LIMITATIONS

Cross-sectional design and loss of granularity due to harmonization.

CONCLUSION

More research is needed to understand heterogenous longitudinal patterns of cognitive change in BD and understand whether particular cognitive domains might be affected in OABD in order to develop new therapeutic efforts for cognitive dysfunction OABD.

Pathophysiology in cortico-amygdala circuits and excessive aversion processing: the role of oligodendrocytes and myelination

Stress-related psychiatric illnesses, such as major depressive disorder, anxiety and post-traumatic stress disorder, present with alterations in emotional processing, including excessive processing of negative/aversive stimuli and events. The bidirectional human/primate brain circuit comprising anterior cingulate cortex and amygdala is of fundamental importance in processing emotional stimuli, and in rodents the medial prefrontal cortex-amygdala circuit is to some extent analogous in structure and function. Here, we assess the comparative evidence for: (i) Anterior cingulate/medial prefrontal cortex<->amygdala bidirectional neural circuits as major contributors to aversive stimulus processing; (ii) Structural and functional changes in anterior cingulate cortex<->amygdala circuit associated with excessive aversion processing in stress-related neuropsychiatric disorders, and in medial prefrontal cortex<->amygdala circuit in rodent models of chronic stress-induced increased aversion reactivity; and (iii) Altered status of oligodendrocytes and their oligodendrocyte lineage cells and myelination in anterior cingulate/medial prefrontal cortex<->amygdala circuits in stress-related neuropsychiatric disorders and stress models. The comparative evidence from humans and rodents is that their respective anterior cingulate/medial prefrontal cortex<->amygdala circuits are integral to adaptive aversion processing. However, at the sub-regional level, the anterior cingulate/medial prefrontal cortex structure-function analogy is incomplete, and differences as well as similarities need to be taken into account. Structure-function imaging studies demonstrate that these neural circuits are altered in both human stress-related neuropsychiatric disorders and rodent models of stress-induced increased aversion processing. In both cases, the changes include altered white matter integrity, albeit the current evidence indicates that this is decreased in humans and increased in rodent models. At the cellular-molecular level, in both humans and rodents, the current evidence is that stress disorders do present with changes in oligodendrocyte lineage, oligodendrocytes and/or myelin in these neural circuits, but these changes are often discordant between and even within species. Nonetheless, by integrating the current comparative evidence, this review provides a timely insight into this field and should function to inform future studies-human, monkey and rodent-to ascertain whether or not the oligodendrocyte lineage and myelination are causally involved in the pathophysiology of stress-related neuropsychiatric disorders.

Bipolar symptoms, somatic burden and functioning in older-age bipolar disorder: A replication study from the global aging & geriatric experiments in bipolar disorder database (GAGE-BD) project

OBJECTIVES

The Global Aging & Geriatric Experiments in Bipolar Disorder Database (GAGE-BD) project pools archival datasets on older age bipolar disorder (OABD). An initial Wave 1 (W1; n = 1369) analysis found both manic and depressive symptoms reduced among older patients. To replicate this finding, we gathered an independent Wave 2 (W2; n = 1232, mean ± standard deviation age 47.2 ± 13.5, 65% women, 49% aged over 50) dataset.

DESIGN/METHODS

Using mixed models with random effects for cohort, we examined associations between BD symptoms, somatic burden and age and the contribution of these to functioning in W2 and the combined W1 + W2 sample (n = 2601).

RESULTS

Compared to W1, the W2 sample was younger (p < 0.001), less educated (p < 0.001), more symptomatic (p < 0.001), lower functioning (p < 0.001) and had fewer somatic conditions (p < 0.001). In the full W2, older individuals had reduced manic symptom severity, but age was not associated with depression severity. Age was not associated with functioning in W2. More severe BD symptoms (mania p ≤ 0.001, depression p ≤ 0.001) were associated with worse functioning. Older age was significantly associated with higher somatic burden in the W2 and the W1 + W2 samples, but this burden was not associated with poorer functioning.

CONCLUSIONS

In a large, independent sample, older age was associated with less severe mania and more somatic burden (consistent with previous findings), but there was no association of depression with age (different from previous findings). Similar to previous findings, worse BD symptom severity was associated with worse functioning, emphasizing the need for symptom relief in OABD to promote better functioning.

Daily mood and cognitive performance of women with and without bipolar disorder: role of menopausal status

We examined the role of menopausal status in daily mood and cognitive performance among women with bipolar disorder (BD) compared to healthy comparison women. We analyzed the association of menopausal status, bipolar diagnosis, and their interaction on daily mood assessed by mobile surveys and attentional performance measured multiple times over 2 weeks. Menopausal status was associated with more daily negative affect in women with BD, but not related to attentional performance.

Bipolar Disorder Among Older Adults: Newer Evidence to Guide Clinical Practice

The term older-age bipolar disorder (OABD) refers to patients with bipolar disorder who are ages 50 and older. Research findings suggest important differences, including the attenuation of manic symptoms with age and the occurrence of multiple somatic comorbid conditions. Although the pharmacological treatment of OABD is fairly similar, adverse effects, somatic comorbidity, and drug-drug interactions are more common. Lithium is effective in treating OABD and may have the potential to be neuroprotective. Anticonvulsants and second-generation antipsychotics have a growing evidence supporting their use in treating OABD. Behavioral intervention can be a helpful adjunct to pharmacological treatment. Clinicians and health care systems need to be prepared to provide care and services to individuals with bipolar disorder throughout the life span. Although older adults have typically been excluded from bipolar disorder RCTs, emerging efforts organized by global advocates and harnessing teams of clinicians and scientists have the potential to advance care.

Prolonged Unmet Mental Health Needs of the 2017 Pohang Earthquake Survivors

OBJECTIVE

Two years after the 2017 Pohang earthquake, some people sought follow-up mental health support. The demographic and clinical characteristics of this unique group of people were investigated to identify some insights on the predisposing factors of the longterm need for psychiatric help after a severe earthquake disaster.

METHODS

De-identified data from those seeking mental health support 2 years after the 2017 Pohang earthquake were used. The descriptive statistics of demographic and clinical characteristics of the study group was identified and paired with general population data obtained from open and public governmental websites. Sex, age distribution, destruction of house, and psychiatric disorder were compared between the follow-up sample and general population.

RESULTS

The proportion of women in the group seeking support was two times higher than that in the general population, and people ages between 50 and 70 years commonly sought support. The severity of home destruction was higher among people who sought and needed follow-up mental health support programs than in the general population. There was a higher proportion of people with psychiatric disorders in the group seeking support than in the general population.

CONCLUSION

The need for long-term mental health support 2 years after an earthquake was higher in women than in men and those aged between 50 and 70 years, and those with a previous psychiatric history and with a higher severity of home destruction, which lead to necessitating leaving the home. Future earthquake response should include screening and psychiatric treatment referral and residential support in vulnerable people.

BrainAge of patients with severe late-life depression referred for electroconvulsive therapy

BACKGROUND

Severe depression is associated with accelerated brain aging. BrainAge gap, the difference between predicted and observed BrainAge, was investigated in patients with late-life depression (LLD). We aimed to examine BrainAge gap in LLD and its associations with clinical characteristics indexing LLD chronicity, current severity, prior to electroconvulsive therapy (ECT) and ECT outcome.

METHODS

Data was analyzed from the Mood Disorders in Elderly treated with Electroconvulsive Therapy (MODECT) study. A previously established BrainAge algorithm (BrainAge R by James Cole, (https://github.com/james-cole/brainageR)) was applied to pre-ECT T1-weighted structural MRI-scans of 42 patients who underwent ECT.

RESULTS

A BrainAge gap of 1.8 years (SD = 5.5) was observed, Cohen's d = 0.3. No significant associations between BrainAge gap, number of previous episodes, current episode duration, age of onset, depression severity, psychotic symptoms or ECT outcome were observed.

LIMITATIONS

Limited sample size.

CONCLUSIONS

Our initial findings suggest an older BrainAge than chronological age in patients with severe LLD referred for ECT, however with high degree of variability and direction of the gap. No associations were found with clinical measures. Larger samples are needed to better understand brain aging and to evaluate the usability of BrainAge gap as potential biomarker of prognosis an treatment-response in LLD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02667353.

Bipolar I and bipolar II subtypes in older age: Results from the Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) project

OBJECTIVES

The distinction between bipolar I disorder (BD-I) and bipolar II disorder (BD-II) has been a topic of long-lasting debate. This study examined differences between BD-I and BD-II in a large, global sample of OABD, focusing on general functioning, cognition and somatic burden as these domains are often affected in OABD.

METHODS

Cross-sectional analyses were conducted with data from the Global Aging and Geriatric Experiments in Bipolar Disorder (GAGE-BD) database. The sample included 963 participants aged ≥50 years (714 BD-I, 249 BD-II). Sociodemographic and clinical factors were compared between BD subtypes including adjustment for study cohort. Multivariable analyses were conducted with generalized linear mixed models (GLMMs) and estimated associations between BD subtype and (1) general functioning (GAF), (2) cognitive performance (g-score) and (3) somatic burden, with study cohort as random intercept.

RESULTS

After adjustment for study cohort, BD-II patients more often had a late onset ≥50 years (p = 0.008) and more current severe depression (p = 0.041). BD-I patients were more likely to have a history of psychiatric hospitalization (p < 0.001) and current use of anti-psychotics (p = 0.003). Multivariable analyses showed that BD subtype was not related to GAF, cognitive g-score or somatic burden.

CONCLUSION

BD-I and BD-II patients did not differ in terms of general functioning, cognitive impairment or somatic burden. Some clinical differences were observed between the groups, which could be the consequence of diagnostic definitions. The distinction between BD-I and BD-II is not the best way to subtype OABD patients. Future research should investigate other disease specifiers in this population.

Predictors of functional impairment in bipolar disorder: Results from 13 cohorts from seven countries by the global bipolar cohort collaborative

OBJECTIVES

Persistent functional impairment is common in bipolar disorder (BD) and is influenced by a number of demographic, clinical, and cognitive features. The goal of this project was to estimate and compare the influence of key factors on community function in multiple cohorts of well-characterized samples of individuals with BD.

METHODS

Thirteen cohorts from 7 countries included n = 5882 individuals with BD across multiple sites. The statistical approach consisted of a systematic uniform application of analyses across sites. Each site performed a logistic regression analysis with empirically derived "higher versus lower function" as the dependent variable and selected clinical and demographic variables as predictors.

RESULTS

We found high rates of functional impairment, ranging from 41 to 75%. Lower community functioning was associated with depressive symptoms in 10 of 12 of the cohorts that included this variable in the analysis. Lower levels of education, a greater number of prior mood episodes, the presence of a comorbid substance use disorder, and a greater total number of psychotropic medications were also associated with low functioning.

CONCLUSIONS

The bipolar clinical research community is poised to work together to characterize the multi-dimensional contributors to impairment and address the barriers that impede patients' complete recovery. We must also identify the core features which enable many to thrive and live successfully with BD. A large-scale, worldwide, prospective longitudinal study focused squarely on BD and its heterogeneous presentations will serve as a platform for discovery and promote major advances toward optimizing outcomes for every individual with this illness.

The interplay of daily affect and impulsivity measured by mobile surveys in bipolar disorder

Background

Impulsivity is a prominent feature of bipolar disorder associated with various negative sequelae; moreover, it may be a precursor to shifts in affect or mood, but little is known about its association with affect on a day-to-day timescale. Ecological momentary assessments (a method that captures moment-to-moment ratings of psychological states by repeatedly sampling the same individual) of impulsivity and affect using mobile surveys allow for more nuanced examination of mechanisms of mood and behavior dysregulation. However, few existing studies have validated an ecological momentary assessment of impulsivity in bipolar disorder and examined its time-lagged associations with positive and negative affect. 70 participants with bipolar disorder and 102 healthy comparisons participated in an intensive longitudinal study: they underwent 14 days of ecological momentary assessment data collection annually for 1–4 years. Multiple measures of impulsivity and affect were collected using self-report, behavioral, and ecological momentary assessment modalities; these measures were compared, and levels of impulsivity were compared between bipolar disorder and healthy comparison groups. Time-lagged analyses using daily means explored the next-day predictive relationship of impulsivity on positive/negative affect, and vice versa.

Results

The ecological momentary measure of impulsivity was moderately correlated with the self-report but not behavioral impulsivity measure. Bipolar disorder participants evinced higher self-report, behavioral, and daily impulsivity than healthy comparison participants. Time-lagged analyses revealed a bi-directional association between high impulsivity and high next-day negative (but not positive) affect. Post hoc analyses showed that impulsivity specifically predicted next-day anger and anxiety.

Conclusions

Our multimodal assessment of impulsivity allowed for an examination of the day-to-day course of impulsivity and affect, crucial steps toward understanding the mechanisms of mood symptom and episode onset in bipolar disorder.

Comparing continuous and harmonized measures of depression severity in older adults with bipolar disorder: Relationship to functioning

OBJECTIVE

Harmonizing different depression severity scales often requires creation of categorical variables that may decrease the sensitivity of the measure. Our aim was to compare the associations between categorical and continuous and harmonized measures of depression and global functioning in a large dataset of older age patients with bipolar disorder (OABD).

METHOD

In the Global Aging & Geriatric Experiments in Bipolar Disorder Database (GAGE-BD) the 17-item Hamilton Depression scale (HAM-D), Montgomery Asberg Depression Rating Scale (MADRS) or the Center for Epidemiological Studies Depression scales (CES-D) was used to assess current depressive symptoms, while the Global Assessment of Functioning (GAF) assessed functional status. Data were harmonized from 8 OABD studies (n = 582). In each subsample, the relationship of depression severity as a continuous and categorical measure was compared to GAF. In the total sample, harmonized ordinal depression categories were compared to GAF.

RESULTS

Effect size and variance explained by the model for the categorical measure in the total sample was higher than both the categorical and continuous measure in the CES-D subsample, higher than the categorical but lower than the continuous measure in the HAM-D subsample, and lower than both the categorical and continuous measures in the MADRS subsample.

LIMITATIONS

All included studies have different inclusion and exclusion criteria, study designs, and differ in aspects of sociodemographic variables.

CONCLUSIONS

Associations were only slightly larger for the continuous vs categorical measures of depression scales. Harmonizing different depression scales into ordinal categories for analyses is feasible without losing statistical power.

Mobile survey engagement by older adults is high during multiple phases of the COVID-19 pandemic and is predicted by baseline and structural factors

Digital surveys, such as mobile phone ecological momentary assessment (EMA), bear the potential to assess and target individual wellbeing in a personalized, real-time approach and allow for interaction in situations when in-person contact is not possible, such as during the coronavirus pandemic. While the use of digital technology might especially benefit research in older adults who find themselves in circumstances of reduced mobility, little is known about their barriers to adherence. We investigated baseline and structural factors that predict study withdrawal and adherence from daily smartphone EMA self-report surveys in the StayWELL Study. The StayWELL study is a longitudinal, observational study on the relationship between social restrictions during the coronavirus pandemic and mental well-being in 95 community-dwelling older aged adults (67–87 years) who were participants in a randomized clinical trial using EMA. Withdrawal was associated with less research staff changes and less likely in participants that reached the study mid-point. No baseline characteristics predicted withdrawal. Main reasons for withdrawal were communication issues, i.e. staff not being able to contact participants. We found an adherence rate of 82% and no fatigue effects. Adherence was predicted by education status, study participation duration, reaching the study midpoint and time between study start and enrollment. COVID infections or supporting people in the household was not related to adherence. To conclude, it is feasible to conduct an EMA study in older people without impacting engagement during a pandemic. Furthermore, personal characteristics and smartphone operating system (Android vs. iOS) used did not relate to engagement, allowing for a broad distribution of digital health technologies. Our study adds information on single predictive variables relevant for adherence and withdrawal from EMA smartphone surveys in older people that can inform the design of future digital EMA research to maximize engagement and reliability of study results.

Peripheral inflammation levels associated with degree of advanced brain aging in schizophrenia

Brain structural abnormalities have been demonstrated in schizophrenia (SZ); these resemble those seen in typical aging, but are seen at younger ages. Furthermore, SZ is associated with accelerated global brain aging, as measured by brain structure-based brain predicted age difference (Brain-PAD). High heterogeneity exists in the degree of brain abnormalities in SZ, and individual differences may be related to levels of peripheral inflammation and may relate to cognitive deficits and negative symptoms. The goal of our study was to investigate the relationship between brain aging, peripheral inflammation, and symptoms of SZ. We hypothesized older brain-PAD in SZ vs. healthy comparison (HC) participants, as well as positive relationships of brain-PAD with peripheral inflammation markers and symptoms in SZ. We analyzed data from two cross-sectional studies in SZ (n = 26; M/F: 21/5) and HC (n = 28; 20/8) (22-64 years). Brain-PAD was calculated using a previously validated Gaussian process regression model applied to raw T1-weighted MRI data. Plasma levels of inflammatory biomarkers (CRP, Eotaxin, Fractalkine, IP10, IL6, IL10, ICAM1, IFNγ, MCP1, MIP1β, SAA, TNFα, VEGF, VCAM1) and cognitive and negative symptoms were assessed. We observed a higher brain-PAD in SZ vs. HC, and advanced brain age relative to chronological age was related to higher peripheral levels of TNFα in the overall group and in the SZ group; other inflammatory markers were not related to brain-PAD. Within the SZ group, we observed no association between cognitive or negative symptoms and brain-PAD. These results support our hypothesis of advanced brain aging in SZ. Furthermore, our findings on the relationship of the pro-inflammatory cytokine TNFα with higher brain-PAD of SZ are relevant to explain heterogeneity of brain ages in SZ, but we did not find strong evidence for cognitive or negative symptom relationships with brain-PAD.

Altered neuroaxonal integrity in schizophrenia and major depressive disorder assessed with neurofilament light chain in serum

BACKGROUND

Schizophrenia (SZ) and major depressive disorders (MDD) have been frequently linked to anatomical brain alterations. However, the relationship between brain pathology, inflammation and clinical symptoms in these disorders is still unclear. Thus, by applying novel blood markers of neuroaxonal integrity such as neurofilament light chain (NfL), we can now address main issues in psychiatric research and potentially offer innovative diagnostic tools toward better clinical characterizations and monitoring in both SZ and MDD.

METHODS

NfL levels were measured in serum of 44 patients with SZ and in 41 patients with MDD applying single molecule array technology and compared to a healthy norm population. Main inflammatory markers (C- reactive protein, interleukins IL-6 and IL-10) were measured to define patients with inflammatory phenotype. The Digit Symbol Substitution Task (DSST) and the Letter-Number-Sequencing Task were performed to estimate cognitive function in both groups.

RESULTS

NfL levels in MDD group (but not in SZ group) were significantly higher than reference values of healthy norm population. A higher than expected proportion of patients with NfL levels above age-specific cut-off values was observed in both SZ and MDD groups. No correlation was observed between NfL and inflammatory markers. A negative correlation between DSST and NfL-values was observed in patients with MDD.

CONCLUSIONS

Both SZ and MDD showed elevated serum levels of NfL, which were independent from inflammatory markers but associated with cognitive performance.

Chemokine MCP1 is associated with cognitive flexibility in schizophrenia: A preliminary analysis

BACKGROUND

Peripheral levels of pro-inflammatory biomarkers have been shown to be altered in schizophrenia (SZ) and associated with cognitive impairments, but their relevance to specific cognitive domains remains unclear.

METHODS

Plasma levels of cytokines, chemokines, and vascular biomarkers were quantified and compared between SZ and healthy comparison (HC) groups. Cognition was assessed using the Delis-Kaplan Executive Function System Trail Making (TM) and Color Word Interference (CWI) tests. Linear regression analyses examined differential relationships of inflammatory biomarkers with executive function between groups.

RESULTS

Plasma levels of TNFα, ICAM1, and MCP1 were higher in individuals with SZ compared to HCs. Higher level of MCP1 was associated with increased CWI Inhibition Switching Errors in SZ but not HCs.

CONCLUSION

Like other studies, we found evidence for increased peripheral inflammation in SZ. We also showed that SZ with particularly high MCP1 levels had poor cognitive flexibility. Interventions to reduce chemokine elevations might prove beneficial for cognitive performance.

Quinolinic acid is associated with cognitive deficits in schizophrenia but not major depressive disorder

Tryptophan and its catabolites (TRYCATs) have been suggested to link peripheral immune system activation and central neurotransmitter abnormalities with relevance to the etio-pathophysiology of schizophrenia (SZ) and major depressive disorder (MDD). The relationship to different psychopathological dimensions within these disorders however remains to be elucidated. We thus investigated potential group differences of tryptophan, kynurenine, kynurenic acid, 3-hydroxy kynurenine and quinolinic acid in the plasma of 19 healthy controls (HC), 45 patients with SZ and 43 patients with MDD and correlated plasma proteins with the "motivation and pleasure" dimension and cognition. After correcting for the covariates age, sex, body mass index, smoking and medication, patients with MDD showed lower kynurenine and 3-hydroxy kynurenine levels compared to HC. Quinolinic acid correlated negatively with composite cognitive score in patients with SZ, indicating that more severe cognitive impairments were associated with increased plasma levels of quinolinic acid. No correlations were found in patients with MDD. These results indicate that MDD and SZ are associated with dysregulation of the kynurenine pathway. Quinolinic acid might be specifically implicated in the pathophysiology of cognitive deficits in patients with SZ. Further studies are needed to determine whether TRYCATs are causally involved in the etiology of these neuropsychiatric disorders.

Peripheral biopterin and neopterin in schizophrenia and depression

Increasing evidence points to a causal involvement of inflammation in the pathogenesis of neuropsychiatric disorders, including major depressive disorder (MDD) and schizophrenia (SZ). Neopterin and biopterin may link peripheral immune system activation and central neurotransmitter alterations. However, it is not fully established whether these alterations are transdiagnostic or disorder-specific and whether they are associated with reward-related psychopathologies. We investigated group differences in neopterin and biopterin in the plasma of healthy comparison (HC) (n=19), SZ (n=45) and MDD (n=43) participants. We then correlated plasma proteins with CRP as a measure for inflammation. Lastly, plasma proteins were correlated with the reward-related psychopathological domain apathy. We found a trend-level difference in biopterin levels and no significant difference in neopterin levels between groups. Within both patient groups, but not HC, we show a significant positive correlation of CRP with neopterin but not with biopterin. Further, we observed no significant correlations of plasma proteins with reward-related psychopathology in HC, MDD or SZ. While our study shows trend-level alterations of biopterin with relevance for future research, it does not support the hypothesis that peripheral neopterin or biopterin are associated with reward-related psychopathology.

Increased random exploration in schizophrenia is associated with inflammation

One aspect of goal-directed behavior, which is known to be impaired in patients with schizophrenia (SZ), is balancing between exploiting a familiar choice with known reward value and exploring a lesser known, but potentially more rewarding option. Despite its relevance to several symptom domains of SZ, this has received little attention in SZ research. In addition, while there is increasing evidence that SZ is associated with chronic low-grade inflammation, few studies have investigated how this relates to specific behaviors, such as balancing exploration and exploitation. We therefore assessed behaviors underlying the exploration-exploitation trade-off using a three-armed bandit task in 45 patients with SZ and 19 healthy controls (HC). This task allowed us to dissociate goal-unrelated (random) from goal-related (directed) exploration and correlate them with psychopathological symptoms. Moreover, we assessed a broad range of inflammatory proteins in the blood and related them to bandit task behavior. We found that, compared to HC, patients with SZ showed reduced task performance. This impairment was due to a shift from exploitation to random exploration, which was associated with symptoms of disorganization. Relative to HC, patients with SZ showed a pro-inflammatory blood profile. Furthermore, high-sensitivity C-reactive protein (hsCRP) positively correlated with random exploration, but not with directed exploration or exploitation. In conclusion, we show that low-grade inflammation in patients with SZ is associated with random exploration, which can be considered a behavioral marker for disorganization. hsCRP may constitute a marker for severity of, and a potential treatment target for maladaptive exploratory behaviors.

Associations Between Negative Symptoms and Effort Discounting in Patients With Schizophrenia and Major Depressive Disorder

Deficits in goal-directed decision making and motivation are hallmark characteristics of several neuropsychiatric disorders, including schizophrenia (SZ) and major depressive disorder (MDD). Studies using effort-based decision-making tasks have shown that both patients with SZ and MDD invest less physical effort in order to obtain rewards. However, how these motivational deficits relate to clinically assessed symptom dimensions such as apathy remains controversial. Using a grip-strength-based effort discounting task we assessed effort-based decision-making behavior in healthy controls (HC) (N = 18), patients with SZ (N = 42), and MDD (N = 44). We then investigated how effort discounting relates to different symptom dimensions. There were no differences in effort discounting between HC participants and patients with SZ or MDD. In addition, we did not observe a correlation between effort discounting and negative symptoms (NS) in patients with SZ or MDD. In conclusion, the current study does not support an association between effort discounting and NS in SZ or MDD. Further studies are needed to investigate effort discounting and its relation to psychopathological dimensions across different neuropsychiatric disorders.

Loss Aversion and Risk Aversion in Non-Clinical Negative Symptoms and Hypomania

In the field of behavioral decision-making, "loss aversion" is a behavioral phenomenon in which individuals show a higher sensitivity to potential losses than to gains. Conversely, "risk averse" individuals have an enhanced sensitivity/aversion to options with uncertain consequences. Here we examine whether hypomania or negative symptoms predict the degree of these choice biases. We chose to study these two symptom dimensions because they present a common theme across many syndromes with compromised decision-making. In our exploratory study, we employed a non-clinical sample to dissociate the hypomanic from negative symptom dimension regarding choice behavior. We randomly selected a sample of 45 subjects from a student population (18-37 years) without self-reported psychiatric diagnoses (n = 835). We stratified them based on percentiles into a low hypomania/low negative symptoms (n = 15), a hypomania (n = 15), and a negative symptoms group (n = 15) using the hypomanic personality scale (HPS-30) and community assessment of psychic experiences (CAPE). Participants completed a loss aversion task consisting of forced binary choices between a monetary gamble and a riskless choice without gain or loss. We found a reduced loss aversion in participants with higher negative symptoms. In addition, risk aversion was reduced in participants with higher hypomania and negative symptoms compared to low hypomania/negative symptoms. This study adds to the understanding of underlying psychological mechanisms of loss and risk aversion. Given the partially opposing nature of hypomania and negative symptoms, further work is needed to examine whether they affect loss and risk aversion via dissociable mechanisms.

Meaning in Life and Its Relationship With Physical, Mental, and Cognitive Functioning: A Study of 1,042 Community-Dwelling Adults Across the Lifespan

OBJECTIVE

To examine the relationship of presence and search for meaning in life with age, physical and mental well-being, and cognitive functioning across the adult lifespan.

METHODS

Cross-sectional data from 1,042 adults in the Successful AGing Evaluation (SAGE)-a multicohort study of adult community-dwelling residents of San Diego County, California-were analyzed. Presence of meaning ("Presence") and search for meaning in life ("Search") were assessed with the Meaning in Life Questionnaire. Physical and mental well-being were measured using the Short Form 36 Health Survey (SF-36). Telephone Interview for Cognitive Status-modified was employed to screen for overall cognitive function. Study data were collected from January 2013 to June 2014.

RESULTS

Presence of meaning exhibited an inverted U-shaped relationship whereas Search showed a U-shaped relationship with age (with Presence peaking and Search reaching the lowest point around age 60). Statistical modeling using generalized estimating equations revealed that physical well-being (SF-36 physical composite score) correlated negatively with age (P < .001) and positively with Presence (P < .001), and there was an age group x Presence interaction (P = .018), such that the relationship was stronger in subjects over age 60. Mental well-being correlated positively with age (P < .001) and Presence (P < .001) and negatively with Search (P = .002). Cognitive function correlated inversely with age (P < .001) and with Search (P < .001). Significant covariates of Presence and Search had small effect sizes, except for a medium effect size for satisfaction with life and Presence in adults over age 60 (P < .001).

CONCLUSIONS

Presence and search for meaning in life are important for health and well-being, though the relationships differ in adults younger and older than 60 years. Better understanding of the longitudinal relationships of meaning of life with well-being is warranted to design interventions to increase meaning of life and improve health and functioning.

[Negative symptoms in schizophrenia - overview and practical implications]

Negative symptoms in schizophrenia can be categorized in the symptom-dimensions of apathy (avolition, anhedonia and social withdrawal) and reduced expression (blunted affect and alogia). Based on the strong relevance for the quality of life and functional outcome during the course of an illness, a differentiated diagnostic and therapeutic approach is of high importance. Such a differentiation specifies primary negative symptoms (regarded as an integral part of schizophrenia) and secondary negative symptoms (regarded as a result of positive symptoms, comorbid depression, effects of antipsychotic medication, substance abuse or social deprivation). The following overview will summarize the various aspects of negative symptoms and discuss current diagnostic and therapeutic recommendations.

Negativsymptome der Schizophrenie – ein Überblick

Zusammenfassung. Negativsymptome der Schizophrenie umfassen die Symptomgruppen der Apathie (Antriebsminderung, Verlust von Freude und sozialer Rückzug) und des reduzierten Ausdrucks (Sprachverarmung und Affektverflachung). Negativsymptome sind von grosser Relevanz für den Erkrankungsverlauf, da sie die Lebensqualität und das Funktionsniveau im Alltag stark beeinträchtigen. In diagnostischer Hinsicht empfiehlt sich die Unterscheidung in primäre Negativsymptome (als integraler Bestandteil der Schizophrenie) und sekundäre Negativsymptome (als Folge von Positivsymptomen, einer komorbiden Depression, dämpfenden Nebenwirkungen von Antipsychotika, substanzinduziert oder Umgebungsbedingt). Neben der Beschreibung der verschiedenen Aspekte der Negativsymptome erläutert die vorliegende Übersichtsarbeit die Pathophysiologie und die aktuellen Empfehlungen zu Diagnostik und Therapie, basierend auf dem Konzept der primären und sekundären Negativsymptome.

Differential effects of peripheral and brain tumor necrosis factor on inflammation, sickness, emotional behavior and memory in mice

Tumor necrosis factor alpha (TNF) is increased in depression and clinical-trial evidence indicates that blocking peripheral TNF has some antidepressant efficacy. In rodents, peripheral or intracerebroventricular TNF results in sickness e.g. reduced body weight, altered emotional behavior and impaired memory. However, the underlying pathways and responsible brain regions are poorly understood. The aim of this mouse study was to increase understanding by comparing the effects of sustained increases in TNF in the circulation, in brain regions impacted by increased circulating TNF, or specific brain regions. Increased peripheral TNF achieved by repeated daily injection (IP-TNF) or osmotic pump resulted in decreased body weight, decreased saccharin (reward) consumption, and increased memory of an aversive conditioned stimulus. These effects co-occurred with increased plasma interleukin-6 and increased IP-derived TNF in brain peri-ventricular regions. An adenovirus-associated viral TNF vector (AAV-TNF) was constructed, brain injection of which resulted in dose-dependent, sustained and region-specific TNF expression, and was without effect on blood cytokine levels. Lateral ventricle AAV-TNF yielded increased TNF in the same brain regions as IP-TNF. In contrast to IP-TNF it was without effect on body weight, saccharin consumption and fear memory, although it did increase anxiety. Hippocampal AAV-TNF led to decreased body weight. It increased conditioning to but not subsequent memory of an aversive context, suggesting impaired consolidation; it also increased anxiety. Amygdala AAV-TNF was without effect on body weight and aversive stimulus learning-memory, but reduced saccharin consumption and increased anxiety. This study adds significantly to the evidence that both peripheral and brain region-specific increases in TNF lead to both sickness and depression- and anxiety disorder-relevant behavior and do so via different pathways. It thereby highlights the complexity in terms of indirect and direct pathways via which increased TNF can act and which need to be taken into account when considering it as a therapeutic target.

Acute kidney injury after liver transplantation: incidence and mortality

INTRODUCTION

Patients undergoing orthotopic liver transplantation often present with acute kidney injury (AKI) in the postoperative period. It has been associated with a greater number of complications and high mortality rates. The goal of this study was to determine the incidence of AKI during the early posttransplant period and mortality in patients undergoing orthotopic liver transplantation in our hospital.

PATIENTS AND METHODS

In this retrospective cohort study, we reviewed the medical records of all patients aged >18 years undergoing liver transplantation from April 2008 to April 2011. The exclusion criteria were a glomerular filtration rate (estimated by using the Modification of Diet in Renal Disease formula) <60 mL/min/1.73 m(2) or AKI at the time of transplantation. AKI was defined as an increase ≥50% from preoperative baseline serum creatinine levels during the hospitalization period.

RESULTS

Of 113 selected patients, 78 (69%) were male. The mean age was 54.03 ± 9.38 years. The mean preoperative baseline creatinine level was 0.94 ± 0.15 mg/dL, and the estimated glomerular filtration rate was 87.09 ± 19.67 mL/min/1.73 m(2). The mean calculated Model for End-Stage Liver Disease score was 13. Hepatitis C serology was present in 70.8%, hepatitis B in 11.5%, hepatocellular carcinoma in 75.2%, and alcohol abuse in 31.9% of patients. The incidence of AKI was 56.6% (64 of 113 patients). The main risk factors for AKI were Model for End-Stage Liver Disease score and diuretic use at baseline. Renal replacement therapy (RRT) was performed in 19.5% (22 of 113) of patients. The hospital mortality rate in the group with AKI was 25% (16 of 64 patients) and 6.1% (3 of 49 patients) between patients without AKI (odds ratio, 5.11 [confidence interval, 1.39-18.7]; P < .01]. Among patients who underwent RRT, the in-hospital mortality rate was 54.5% (12 of 22 patients) compared with 7.7% (7 of 91 patients) from the other remaining patient cohort (odds ratio, 14.40 [confidence interval, 4.60-45.00]; P < .01).

CONCLUSIONS

There was a high incidence of AKI in patients undergoing liver transplantation and an increased risk of mortality among patients who needed RRT.

Translating the evidence for gene association with depression into mouse models of depression-relevant behaviour: current limitations and future potential

Depression is characterised by high prevalence and complex, heterogeneous psychopathology. At the level of aetio-pathology, considerable research effort has been invested to identify specific gene polymorphisms associated with increased depression prevalence. Genome-wide association studies have not identified any risk polymorphisms, and candidate gene case-control studies have identified a small number of risk polymorphisms. It is increasingly recognised that interaction between genotype and environmental factors (G×E), notably stressful life events, is the more realistic unit of depression aetio-pathology, with G×E evidence described for a small number of risk polymorphisms. An important complementary approach has been to describe genes exhibiting brain region-specific expression changes in depression. Mouse models of depression informed by the human evidence allow for the study of causality, but to-date have also yielded limited insights into depression aetio-pathology. This review of the translational evidence integrates human and mouse research approaches and evidence. It also makes specific recommendations in terms of how future research in human and mouse should be designed in order to deliver evidence for depression aetio-pathology and thereby to inform the development of novel and improved antidepressant treatments.

Functional ADA polymorphism increases sleep depth and reduces vigilant attention in humans

Homeostatically regulated slow-wave oscillations in non-rapid eye movement (REM) sleep may reflect synaptic changes across the sleep-wake continuum and the restorative function of sleep. The nonsynonymous c.22G>A polymorphism (rs73598374) of adenosine deaminase (ADA) reduces the conversion of adenosine to inosine and predicts baseline differences in sleep slow-wave oscillations. We hypothesized that this polymorphism affects cognitive functions, and investigated whether it modulates electroencephalogram (EEG), behavioral, subjective, and biochemical responses to sleep deprivation. Attention, learning, memory, and executive functioning were quantified in healthy adults. Right-handed carriers of the variant allele (G/A genotype, n = 29) performed worse on the d2 attention task than G/G homozygotes (n = 191). To test whether this difference reflects elevated homeostatic sleep pressure, sleep and sleep EEG before and after sleep deprivation were studied in 2 prospectively matched groups of G/A and G/G genotype subjects. Deep sleep and EEG 0.75- to 1.5-Hz oscillations in non-REM sleep were significantly higher in G/A than in G/G genotype. Moreover, attention and vigor were reduced, whereas waking EEG alpha activity (8.5-12 Hz), sleepiness, fatigue, and α-amylase in saliva were enhanced. These convergent data demonstrate that genetic reduction of ADA activity elevates sleep pressure and plays a key role in sleep and waking quality in humans.

Akt2/PKBbeta-sensitive regulation of renal phosphate transport

AIM

The protein kinase B (PKB)/Akt is known to stimulate the cellular uptake of glucose and amino acids. The kinase is expressed in proximal renal tubules. The present study explored the influence of Akt/PKB on renal tubular phosphate transport.

METHODS

The renal phosphate transporter NaPi-IIa was expressed in Xenopus oocytes with or without PKB/Akt and Na(+) phosphate cotransport determined using dual electrode voltage clamp. Renal phosphate excretion was determined in Akt2/PKBbeta knockout mice (akt2(-/-)) and corresponding wild-type mice (akt2(+/+)). Transporter protein abundance was determined using Western blotting and phosphate transport by (32)P uptake into brush border membrane vesicles.

RESULTS

The phosphate-induced current in NaPi-IIa-expressing Xenopus oocytes was significantly increased by the coexpression of Akt/PKB. Phosphate excretion [micromol per 24 h per g BW] was higher by 91% in akt2(-/-) than in akt2(+/+) mice. The phosphaturia of akt2(-/-) mice occurred despite normal transport activity and expression of the renal phosphate transporters NaPi-IIa, NaPi-IIc and Pit2 in the brush border membrane, a significantly decreased plasma PTH concentration (by 46%) and a significantly enhanced plasma 1,25-dihydroxyvitamin D(3) concentration (by 46%). Moreover, fractional renal Ca(2+) excretion was significantly enhanced (by 53%) and bone density significantly reduced (by 11%) in akt2(-/-) mice.

CONCLUSIONS

Akt2/PKBbeta plays a role in the acute regulation of renal phosphate transport and thus contributes to the maintenance of phosphate balance and adequate mineralization of bone.

Up-regulation of hypertonicity-activated myo-inositol transporter SMIT1 by the cell volume-sensitive protein kinase SGK1

Mechanisms of regulatory cell volume increase following cell shrinkage include accumulation of organic osmolytes such as betaine, taurine, sorbitol, glycerophosphorylcholine (GPC) and myo-inositol. Myo-inositol is taken up by the sodium-myo-inositol-transporter SMIT1 (SLC5A3) expressed in a wide variety of cell types. Hypertonicity induces the transcription of the SMIT1 gene upon binding of the transcription factor tonicity enhancer binding protein (TonEBP) to tonicity responsive enhancers (TonE) in the SMIT1 promoter region. However, little is known about post-translational regulation of the carrier protein. In this study we show that SMIT1 is modulated by the serum- and glucocorticoid-inducible kinase SGK1, a protein genomically up-regulated by hypertonicity. As demonstrated by two-electrode voltage-clamp in the Xenopus oocyte expression system, SMIT1-mediated myo-inositol-induced currents are up-regulated by coexpression of wild type SGK1 and constitutively active (S422D)SGK1 but not by inactive (K127N)SGK1. The increase in SMIT1 activity is due to an elevated cell surface expression of the carrier while its kinetic properties remain unaffected. According to the decay of SMIT1 activity in the presence of brefeldin A, SGK1 stabilizes the SMIT1 protein in the plasma membrane. The SGK isoforms SGK2, SGK3 and the closely related protein kinase B (PKB) are similarly capable of activating SMIT1 activity. SMIT1-mediated currents are decreased by coexpression of the ubiquitin-ligase Nedd4-2, an effect counteracted by additional coexpression of SGK1. In conclusion, the present observations disclose SGK isoforms and protein kinase B as novel regulators of SMIT1 activity.

Kidney transplantation with Belzer or Custodiol solution: a randomized prospective study

PURPOSE

The purpose of this study was to compare the Belzer vs Custodiol solutions for cadaveric kidney perfusion in relation to delayed graft function, renal function, acute rejection episodes, and patient and graft survivals.

METHODS

This randomized prospective study included 42 kidneys and 9 simultaneous kidney and pancreas recipients from December 2002 to February 2004, namely 24 in the Custodiol arm and 27 in the Belzer arm. We analyzed delayed graft function frequency, acute rejection episodes (biopsy proven), renal function (creatinine at 1, 6, and 12 months), as well as graft and patient survivals. Categorical and continuous variables were evaluated as appropriate.

RESULTS

We failed to observe a difference in the immunosuppressant drug protocol, cold ischemia time, or mean recipient or donor age. The prevalence of delayed graft function was 63% among the Belzer arm, and 50% among the Custodiol arm (P = NS). The renal function was the same in both arms at 1, 6, and 12 months. The graft survival after 3 months was 94% among the Belzer group (death from sepsis), and 95% among the Custodiol group (nonfunctioning graft). At 1 year, the results were 78% among the Belzer group (4 deaths from cardiovascular or infectious complications and 2 graft losses), and 79% among the Custodiol group (3 deaths, 1 primary nonfunctioning graft, and 1 graft loss; P = NS). After 12 months follow-up, patient survival was 84% among the Belzer group, and 86% among the Custodiol group. In the first year, the incidences of biopsy-proven acute rejection episodes were 37% among the Belzer group, and 33% among the Custodiol group.

CONCLUSION

Custodiol solution achieved similar results compared with Belzer solution.

Chromatographic, capillary electrophoretic and matrix-assisted laser desorption ionization time-of-flight mass spectrometry analysis of urinary modified nucleosides as tumor markers

Modified nucleosides are formed posttranscriptionally in RNA. During RNA turnover free modified nucleosides are formed which circulate in the blood stream and are excreted in the urine. Their levels are increased in a number of malignant diseases, and they can be used in clinical chemistry as tumor markers. The analysis includes the isolation of the nucleosides from urine with phenylboronate gel and their separation and quantitation by HPLC on C18 columns or by capillary electrophoresis on uncoated columns applying a sodium dodecyl sulfate-borate-phosphate buffer. Identification of the nucleosides is performed with matrix-assisted laser desorption ionization time-of-flight mass spectrometry including post source decay spectra. In two clinical studies the diagnostic value of urinary modified nucleosides is investigated, in a study on children with leukemia and other malignant diseases and a study on women with breast cancer. Candidate markers are pseudouridine, 1-methylguanosine, N2-methylguanosine, 3-methyluridine and 1-methyl-inosine.

Plant plasma membrane. Correlation between glucan synthase II activity and a mannosyl transferase activity

In cotyledons of germinating cucumber seeds (Cucumis sativus), plasma membranes were investigated biochemically and partially characterized. Glucan synthease II was utilized as a marker to locate plasma membrane vesicles within fractions obtained by differential centrifugation or within sucrose gradients used either in zonal centrifugations or in sedimentations to equilibrium density. Thorough homogenization led to a homogeneous population of plasma membrane vesicles which could be clearly separated from mitochondria by centrifugation at 150000 x g for 4 h in a zonal rotor. The profiles of glucan synthase II activity and naphthylphthalamic acid binding coincided with that of a mannosyl transferase activity, monitored by direct transfer of mannose from GDPmannose to endogeneous acceptors.