Limited evidence of autocorrelation signaling upcoming affective episodes: a 12-month e-diary study in patients with bipolar disorder

BACKGROUND

Increased autocorrelation (AR) of system-specific measures has been suggested as a predictor for critical transitions in complex systems. Increased AR of mood scores has been reported to anticipate depressive episodes in major depressive disorder, while other studies found AR increases to be associated with depressive episodes themselves. Data on AR in patients with bipolar disorders (BD) is limited and inconclusive.

METHODS

Patients with BD reported their current mood via daily e-diaries for 12 months. Current affective status (euthymic, prodromal, depressed, (hypo)manic) was assessed in 26 bi-weekly expert interviews. Exploratory analyses tested whether self-reported current mood and AR of the same item could differentiate between prodromal phases or affective episodes and euthymia.

RESULTS

A total of 29 depressive and 20 (hypo)manic episodes were observed in 29 participants with BD. Self-reported current mood was significantly decreased during the two weeks prior to a depressive episode (early prodromal, late prodromal), but not changed prior to manic episodes. The AR was neither a significant predictor for the early or late prodromal phase of depression nor for the early prodromal phase of (hypo)mania. Decreased AR was found in the late prodromal phase of (hypo)mania. Increased AR was mainly found during depressive episodes.

CONCLUSIONS

AR changes might not be better at predicting depressive episodes than simple self-report measures on current mood in patients with BD. Increased AR was mostly found during depressive episodes. Potentially, changes in AR might anticipate (hypo)manic episodes.

Movement disorders after hypoxic brain injury following cardiac arrest in adults

BACKGROUND AND PURPOSE

Post-hypoxic movement disorders and chronic post-hypoxic myoclonus are rare complications after cardiac arrest in adults. Our study investigates the clinical spectrum, neuroimaging results, therapy and prognosis of these debilitating post-hypoxic sequelae.

METHODS

This retrospective study included 72 patients from the neurological intensive care unit at a university hospital, who were diagnosed with hypoxic-ischaemic encephalopathy after cardiac arrest between January 2007 and September 2018. Clinical records were screened for occurrence of post-hypoxic movement disorders and chronic post-hypoxic myoclonus. Affected patients were further analysed for applied neuroprognostic tests, administered therapy and treatment response, and the outcome of these movement disorders and neurological function.

RESULTS

Nineteen out of 72 screened patients exhibited post-hypoxic motor symptoms. Basal ganglia injury was the most likely neuroanatomical correlate of movement disorders as indicated by T1 hyperintensities and hypometabolism of this region in magnetic resonance imaging and positron emission tomography computed tomography. Levomepromazine and intrathecal baclofen showed first promising and mostly prompt responses to control these post-hypoxic movement disorders and even hyperkinetic storms. In contrast, chronic post-hypoxic myoclonus best responded to co-application of clonazepam, levetiracetam and primidone. Remission rates of post-hypoxic movement disorders and chronic post-hypoxic myoclonus were 58% and 50%, respectively. Affected patients seemed to present a rather good recovery of cognitive functions in contrast to the often more severe physical deficits.

CONCLUSIONS

Post-hypoxic movement disorders associated with pronounced basal ganglia dysfunction might be efficiently controlled by levomepromazine or intrathecal baclofen. Their occurrence might be an indicator for a more unfavourable, but often not devastating, neurological outcome.

AB1195 CO-RELATION BETWEEN SELF EFFICACY, DEPRESSION AND PAIN AMONG CAREGIVERS WITH AND WITHOUT ARTHRITIS

Background:

People with arthritis, like others, are often informal caregivers. Caregiving adds burdens of stress and depression. Caregiver studies have shown these to be mitigated by self-efficacy or the confidence to achieve specific caregiving behaviors. Caregivers with arthritis have seldom been studied. We have been unable to find studies specific to caregiving and self-efficacy as they apply to those with and without arthritis. In this study, we evaluated the relationship between self-efficacy, pain, and depression among caregivers with and without arthritis.

Objectives:

1)To examine the correlation between caregiver self-efficacy and depression and pain. 2). To examine how these correlation differ for caregivers with and without arthritis.

Methods:

A caregiver questionnaire was distributed via social media, mainly list serves and blogs to a convenience sample. Those receiving the links were urged to send them to other populations. Respondents self-reported arthritis and weekly hours spent caregiving. They reported pain using a pain (visual numeric scale (1-10)), depression with the Patient Health Questionnaire (PHQ-8), and Self-Efficacy was reported with the short caregiver self-efficacy scale). For caregivers and non-caregivers we compared caregiving hours, pain, depression and self-efficacy. We examined the distribution of caregiving hours by arthritis status and plotted mean pain scores by caregiving hours for caregivers with and without arthritis. The correlation between depression and self-efficacy was measured using Pearson correlation coefficient overall and by arthritis status.

Results:

Over two weeks 155 individuals responded, with data on self-reported arthritis status. Of the respondents, 88% were female and 64% were 50-69 years of age. 46% self-reported arthritis (osteoarthritis was the most common type). Nearly 25% of caregivers reported spending less than 10 hours weekly on caregiving, while approximately 23% reported at the other end of the extreme (at least 40 hours weekly). The distribution by arthritis status of the caregiver is provided in Table 1.

Table 1.Caregiving hoursArthritis0-9 hrs10-19 hrs20-29 hrs30-35 hrs40+ hrsMissingAllNo26 (31%)26 (31%)11 (13%)5 (6%)15 (18%)1 (1%)84 (54.2%)Yes12 (17%)21 (30%)11 (15.5%)7 (9.9%)20 (28%)071 (45.8%)Total38 (24.5%)47 (30.3%)22 (14.2%)12 (7.7%)35 (22.6%)1 (0.7%)155

Caregivers with arthritis reported higher pain in the past week. Mean pain score among caregivers with arthritis was 4.4 (SD 2.2) compared to 2.7 (SD 1.7) among caregivers without arthritis (figure 1). This divergence widened for caregivers with 40 or more hours of caregiving. There was a strong negative correlation (Pearson correlation= – 0.473, p-value <0.0001) between depression and self-efficacy. The correlation was -0.59 for caregivers without arthritis (p=<0.0001, n=74 with data on all three variables) compared to the caregivers self-reporting arthritis (r=-0.35, p=0.006, n=60 with data on all three variables).

Figure 1.

Conclusion:

This study suggests that lower caregiver self-efficacy has a direct and strong association with higher depressive symptoms and that this is more pronounced among caregivers with arthritis. This study also shows that caregivers with arthritis have more pain than caregivers without arthritis, and that this peaks and remains consistent for those doing twenty or more hours of caregiving weekly.. The stronger negative correlation of depression and self-efficacy among patients without arthritis may be explained by other independent contributors (such as pain) to depression in caregivers with arthritis.

References:

[1]Lorig K, Ritter PL, Laurent DD, Yank V. Building Better Caregivers: A Pragmatic 12-Month Trial of a Community-Based Workshop for Caregivers of Cognitively Impaired Adults.J Appl Gerontol. 2019;38(9):1228–1252. doi:10.1177/0733464817741682

Disclosure of Interests:

None declared

298Atrioventricular synchronous pacing in leadless ventricular pacemaker is safe and effective in patients with paroxysmal AV block and atrial arrhythmias

Funding Acknowledgements

Medtronic, Inc.

Background/Introduction

Accelerometer (ACC)-based AV synchronous pacing by tracking atrial activity is feasible using a leadless ventricular pacemaker. Patients may experience variable AV conduction (AVC) and/or atrial arrhythmias during the lifetime of their device. ACC-based AV synchronous pacing should facilitate AVC and pace appropriately in those two common rhythms.

Purpose

To characterize the behavior of ACC-based AV synchronous pacing algorithms during paroxysmal AV block (AVB) and atrial arrhythmias.

Methods

The MARVEL2 (Micra Atrial tRacking using a Ventricular accELerometer) was a 5-hour acute study to assess the efficacy of atrial tracking with a temporarily downloaded algorithm into a Micra leadless pacemaker. Patients with a history of AVB were eligible for inclusion. The MARVEL2 algorithm included a mode-switching algorithm that switched between VDD and VVI-40 depending upon AVC status. The AVC algorithm requires 2 ventricular paces (VP) at 40 bpm out of 4 pacing cycles to switch to VDD.

Results

Overall, 75 patients (age 77.5 ± 11.8 years, 40% female, median time from Micra implant 9.7 months) from 12 centers worldwide were enrolled. During study procedures, 40 patients (53%) had normal sinus rhythm with complete AVB, 18 (24%) had 1:1 AVC, 5 (7%) had varying AVC status, 8 (11%) had atrial arrhythmias, and 2 other rhythms.  Two patients with complete AVB had the AVC mode switch feature disabled due to an idioventricular rate &gt;40 bpm.  Among the 40 subjects with a predominant 3rd degree AVB and normal sinus function the median %VP was 99.9% compared to 0.2% among those with 1:1 AVC (Figure). In the patients with 1:1 AVC, there were 64 opportunities to AVC mode switch with 48 switching to VDI-40. In the other 16 cases (2 patients) the mode remained VDD due to sinus bradycardia varying between 40-45 bpm. High %VP was observed in 2 patients with 1:1 AVC and sinus bradycardia &lt;40 bpm. The AVC mode switch minimized %VP (&lt;1%) in patients with PR intervals &gt; 300 ms (N = 2). Among patients with varying AVC, the algorithm appropriately switched to VDD when the ventricular rate was paced at 40 bpm. During infrequent AVB or AF with ventricular response &gt;40 bpm, VVI-40 mode was maintained.

In patients with AF, the ACC signal was of low amplitude and there was infrequent sensing, resulting in VP at the lower rate (50 bpm). In the one patient with atrial flutter, the ACC was intermittently detected, resulting in VP at 67 bpm (IQR 66-67 bpm).

Conclusion(s)

The mode switching algorithm in the MARVEL2 reduced %VP in patients with 1:1 AVC and appropriately switched to VDD during complete AVB.  If greater AV synchrony or rate support is required, disabling the AVC algorithm may be appropriate for low grade AVB or idioventricular rhythms. In the presence of atrial arrhythmias, the algorithm paced near the lower rate.

Abstract Figure. Distribution of VP% by heart rhythm

Influence of birth cohort on age of onset cluster analysis in bipolar I disorder

Purpose:

Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.

Methods:

The database includes 4037 patients with a diagnosis of bipolar I disorder, previously collected at 36 collection sites in 23 countries. Generalized estimating equations (GEE) were used to adjust the data for country median age, and in some models, birth cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared.

Results:

There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After adjusting for the birth cohort or when considering only those born after 1959, two subgroups were found. With results of either two or three subgroups, the youngest subgroup was more likely to have a family history of mood disorders and a first episode with depressed polarity. However, without adjusting for birth cohort (three subgroups), family history and polarity of the first episode could not be distinguished between the middle and oldest subgroups.

Conclusion:

These results using international data confirm prior findings using single country data, that there are subgroups of bipolar I disorder based on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more useful for research.

[A review of the update of the German S3-guideline on diagnostics and therapy of bipolar disorders 2019]

Since the first publication of the guideline in 2012, which included critically reviewed evidence up to 2010, several hundred articles with new evidence were published and some topics of the clinical consensus needed to be reconsidered. Therefore, it was urgently necessary to revise the guideline to bring them up to date. In this article important revisions and updates are presented and the chances and limitations of the development of the guidelines and their implementation are discussed.

Subject specificity of the correlation between large-scale structural and functional connectivity

Structural connectivity (SC), the physical pathways connecting regions in the brain, and functional connectivity (FC), the temporal coactivations, are known to be tightly linked. However, the nature of this relationship is still not understood. In the present study, we examined this relation more closely in six separate human neuroimaging datasets with different acquisition and preprocessing methods. We show that using simple linear associations, the relation between an individual's SC and FC is not subject specific for five of the datasets. Subject specificity of SC-FC fit is achieved only for one of the six datasets, the multimodal Glasser Human Connectome Project (HCP) parcellated dataset. We show that subject specificity of SC-FC correspondence is limited across datasets due to relatively small variability between subjects in SC compared with the larger variability in FC.

Differentiation of Alzheimer's disease based on local and global parameters in personalized Virtual Brain models

Alzheimer's disease (AD) is marked by cognitive dysfunction emerging from neuropathological processes impacting brain function. AD affects brain dynamics at the local level, such as changes in the balance of inhibitory and excitatory neuronal populations, as well as long-range changes to the global network. Individual differences in these changes as they relate to behaviour are poorly understood. Here, we use a multi-scale neurophysiological model, “The Virtual Brain (TVB)”, based on empirical multi-modal neuroimaging data, to study how local and global dynamics correlate with individual differences in cognition. In particular, we modeled individual resting-state functional activity of 124 individuals across the behavioural spectrum from healthy aging, to amnesic Mild Cognitive Impairment (MCI), to AD. The model parameters required to accurately simulate empirical functional brain imaging data correlated significantly with cognition, and exceeded the predictive capacity of empirical connectomes.

•

Modeled local and global dynamics correlate with individual cognition in Alzheimer's.

•

Proof of concept of The Virtual Brain to characterize individual dynamics

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Brain-behaviour relations depend on the network modeled (whole brain or limbic).

•

Model parameters predict cognition better than metrics of neuroimaging data.

Solar insolation in springtime influences age of onset of bipolar I disorder

OBJECTIVE

To confirm prior findings that the larger the maximum monthly increase in solar insolation in springtime, the younger the age of onset of bipolar disorder.

METHOD

Data were collected from 5536 patients at 50 sites in 32 countries on six continents. Onset occurred at 456 locations in 57 countries. Variables included solar insolation, birth-cohort, family history, polarity of first episode and country physician density.

RESULTS

There was a significant, inverse association between the maximum monthly increase in solar insolation at the onset location, and the age of onset. This effect was reduced in those without a family history of mood disorders and with a first episode of mania rather than depression. The maximum monthly increase occurred in springtime. The youngest birth-cohort had the youngest age of onset. All prior relationships were confirmed using both the entire sample, and only the youngest birth-cohort (all estimated coefficients P < 0.001).

CONCLUSION

A large increase in springtime solar insolation may impact the onset of bipolar disorder, especially with a family history of mood disorders. Recent societal changes that affect light exposure (LED lighting, mobile devices backlit with LEDs) may influence adaptability to a springtime circadian challenge.

[Effects of fine particulate matter from on bronchial epithelial cells]

INTRODUCTION

Ambient air contains a variety of pollutants including solid particles. Human bronchial epithelial cells (HBEC) play a key role following inhalation of these toxic particles. In a cell culture system of HBEC, we investigated the effects of several fractions of Lyons air-derived particles on cell viability/proliferation and production of the inflammatory mediators IL-8 and TGF-β.

METHODS

Air particles were collected in Lyon (France) by filtration of the air and impaction on filters located on a tapered element oscillating microbalance. Several diameter-based fractions of particles were prepared. HBEC were then exposed to different concentrations of these fractions.

RESULTS

HBEC survival was not altered after 48hours of culture in the presence of particles regardless of their diameter and concentration. A dose-dependent inhibitory effect on cell growth was observed for all fractions. The particles caused an increase of both TGF-ß and Il-8 protein levels as a function of their diameters and/or concentrations.

CONCLUSION

Air-derived particle fractions exhibit both an inhibitory effect on cell proliferation and a pro-inflammatory activity on HBEC.

The suicide prevention effect of lithium: more than 20 years of evidence-a narrative review

The management and treatment of patients with suicidal behavior is one of the most challenging tasks for health-care professionals. Patients with affective disorders are at high risk for suicidal behavior, therefore, should be a target for prevention. Numerous international studies of lithium use have documented anti-suicidal effects since the 1970s. Despite the unambiguous evidence of lithium’s anti-suicidal effects and recommendations in national and international guidelines for its use in acute and maintenance therapy of affective disorders, the use of lithium is still underrepresented. The following article provides a comprehensive review of studies investigating the anti-suicidal effect of lithium in patients with affective disorders.

Does lithium reduce acute suicidal ideation and behavior? A protocol for a randomized, placebo-controlled multicenter trial of lithium plus Treatment As Usual (TAU) in patients with suicidal major depressive episode

BACKGROUND

Lithium has proven suicide preventing effects in the long-term treatment of patients with affective disorders. Clinical evidence from case reports indicate that this effect may occur early on at the beginning of lithium treatment. The impact of lithium treatment on acute suicidal thoughts and/or behavior has not been systematically studied in a controlled trial. The primary objective of this confirmatory study is to determine the association between lithium therapy and acute suicidal ideation and/or suicidal behavior in inpatients with a major depressive episode (MDE, unipolar and bipolar disorder according to DSM IV criteria). The specific aim is to test the hypothesis that lithium plus treatment as usual (TAU), compared to placebo plus TAU, results in a significantly greater decrease in suicidal ideation and/or behavior over 5 weeks in inpatients with MDE.

METHODS/DESIGN

We initiated a randomized, placebo-controlled multicenter trial. Patients with the diagnosis of a moderate to severe depressive episode and suicidal thoughts and/or suicidal behavior measured with the Sheehan-Suicidality-Tracking Scale (S-STS) will be randomly allocated to add lithium or placebo to their treatment as usual. Change in the clinician administered S-STS from the initial to the final visit will be the primary outcome.

DISCUSSION

There is an urgent need to identify treatments that will acutely decrease suicidal ideation and/or suicidal behavior. The results of this study will demonstrate whether lithium reduces suicidal ideation and behavior within the first 5 weeks of treatment.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02039479.

Incidence of paroxysmal atrial tachycardias in patients treated with cardiac resynchronization therapy and continuously monitored by device diagnostics

AIMS

Little is known about the incidence of paroxysmal atrial tachycardias (PAT) in patients with heart failure (HF). The availability of cardiac resynchronization therapy (CRT) devices with extended diagnostics for AT enables continuous monitoring of PAT episodes. The aim of the study was to assess the incidence over time of PAT in HF patients treated with CRT.

METHODS AND RESULTS

Consecutive patients in NYHA functional class III or IV despite optimal drug therapy, QRS duration > or = 130 ms, left ventricular ejection fraction < or = 35%, and left ventricular end-diastolic dimension > or = 55 mm were eligible for enrolment. Patients with permanent or persistent atrial fibrillation (AF) were not included in the study. The first follow-up examination was performed 2 weeks after implantation, to optimize atrial sensing and CRT. Subsequent follow-up examinations were carried out 15 and 28 weeks after implantation, to collect the telemetric data. A total of 173 patients (67 +/- 11 years, M 116) were enrolled. Complete arrhythmia monitoring data were available from 120 patients over a mean follow-up of 183 +/- 23 days. Atrial tachycardia episodes were detected through telemetry in 25 of 120 patients (21%) during at least one follow-up examination. Atrial tachycardia episodes were recorded in 29 and 17% (P = NS) of patients with and without previous history of AF, respectively.

CONCLUSION

More than 20% of the overall HF patient population treated with CRT suffer PAT episodes. Paroxysmal atrial tachycardia may interfere with response to CRT. Therefore, telemetric data may be relevant to drive the appropriate therapy in each patient.