The mediating role of health behaviors in the association between depression, anxiety and cancer incidence: an individual participant data meta-analysis

BACKGROUND

Although behavioral mechanisms in the association among depression, anxiety, and cancer are plausible, few studies have empirically studied mediation by health behaviors. We aimed to examine the mediating role of several health behaviors in the associations among depression, anxiety, and the incidence of various cancer types (overall, breast, prostate, lung, colorectal, smoking-related, and alcohol-related cancers).

METHODS

Two-stage individual participant data meta-analyses were performed based on 18 cohorts within the Psychosocial Factors and Cancer Incidence consortium that had a measure of depression or anxiety (N = 319 613, cancer incidence = 25 803). Health behaviors included smoking, physical inactivity, alcohol use, body mass index (BMI), sedentary behavior, and sleep duration and quality. In stage one, path-specific regression estimates were obtained in each cohort. In stage two, cohort-specific estimates were pooled using random-effects multivariate meta-analysis, and natural indirect effects (i.e. mediating effects) were calculated as hazard ratios (HRs).

RESULTS

Smoking (HRs range 1.04-1.10) and physical inactivity (HRs range 1.01-1.02) significantly mediated the associations among depression, anxiety, and lung cancer. Smoking was also a mediator for smoking-related cancers (HRs range 1.03-1.06). There was mediation by health behaviors, especially smoking, physical inactivity, alcohol use, and a higher BMI, in the associations among depression, anxiety, and overall cancer or other types of cancer, but effects were small (HRs generally below 1.01).

CONCLUSIONS

Smoking constitutes a mediating pathway linking depression and anxiety to lung cancer and smoking-related cancers. Our findings underline the importance of smoking cessation interventions for persons with depression or anxiety.

Pre-treatment predictors of cognitive side-effects after treatment with electroconvulsive therapy in patients with depression: A multicenter study

BACKGROUND

Electroconvulsive therapy (ECT) is a highly effective treatment for major depressive episodes (MDE). However, ECT-induced cognitive side-effects remain a concern. Identification of pre-treatment predictors that contribute to these side-effects remain unclear. We examined cognitive performance and individual cognitive profiles over time (up to six months) following ECT and investigated possible pre-treatment clinical and demographic predictors of cognitive decline shortly after ECT.

METHODS

634 patients with MDE from five sites were included with recruitment periods between 2001 and 2020. Linear mixed models were used to examine how cognitive performance, assessed with an extensive neuropsychological test battery, evolved over time following ECT. Next, possible pre-treatment predictors of cognitive side-effects directly after ECT were examined using linear regression.

RESULTS

Directly after ECT, only verbal fluency (animal and letter; p < 0.0001; Cohen's d: -0.25 and -0.29 respectively) and verbal recall (p < 0.0001; Cohen's d: -0.26) significantly declined. However, during three and six months of follow-up, cognitive performance across all domains significantly improved, even outperforming baseline levels. No other pre-treatment factor than a younger age predicted a larger deterioration in cognitive performance shortly after ECT.

LIMITATIONS

There was a substantial amount of missing data especially at 6 months follow-up.

CONCLUSIONS

Our findings show that verbal fluency and memory retention are temporarily affected immediately after ECT. Younger patients may be more susceptible to experiencing these acute cognitive side-effects, which seems to be mostly due to a more intact cognitive functioning prior to ECT. These findings could contribute to decision-making regarding treatment selection, psychoeducation, and guidance during an ECT course.

The development and psychometric evaluation of the Questionnaire Epistemic Trust (QET): A self-report assessment of epistemic trust

Epistemic trust (ET) refers to the predisposition to trust information as authentic, trustworthy and relevant to the self. Epistemic distrust - resulting from early adversity - may interfere with openness to social learning within the therapeutic encounter, reducing the ability to benefit from treatment. The self-report Questionnaire Epistemic Trust (QET) is a newly developed instrument that aims to assess ET. This study presents the first results on the psychometric properties of the QET in both a community and a clinical sample. Our findings indicate that the QET is composed of four meaningful subscales with good to excellent internal consistency. The QET shows relevant associations with related constructs like personality functioning, symptom distress and quality of life. QET scores clearly distinguish between a clinical and community sample and are associated with the quality of the therapeutic alliance. The QET provides a promising, brief and user-friendly instrument that could be used for a range of clinical and research purposes. Future studies with larger samples are needed to strengthen construct validity and to investigate the value of the QET to predict differential treatment responses or to study mechanisms of change.

Depression, anxiety, and the risk of cancer: An individual participant data meta-analysis

BACKGROUND

Depression and anxiety have long been hypothesized to be related to an increased cancer risk. Despite the great amount of research that has been conducted, findings are inconclusive. To provide a stronger basis for addressing the associations between depression, anxiety, and the incidence of various cancer types (overall, breast, lung, prostate, colorectal, alcohol-related, and smoking-related cancers), individual participant data (IPD) meta-analyses were performed within the Psychosocial Factors and Cancer Incidence (PSY-CA) consortium.

METHODS

The PSY-CA consortium includes data from 18 cohorts with measures of depression or anxiety (up to N = 319,613; cancer incidences, 25,803; person-years of follow-up, 3,254,714). Both symptoms and a diagnosis of depression and anxiety were examined as predictors of future cancer risk. Two-stage IPD meta-analyses were run, first by using Cox regression models in each cohort (stage 1), and then by aggregating the results in random-effects meta-analyses (stage 2).

RESULTS

No associations were found between depression or anxiety and overall, breast, prostate, colorectal, and alcohol-related cancers. Depression and anxiety (symptoms and diagnoses) were associated with the incidence of lung cancer and smoking-related cancers (hazard ratios [HRs], 1.06-1.60). However, these associations were substantially attenuated when additionally adjusting for known risk factors including smoking, alcohol use, and body mass index (HRs, 1.04-1.23).

CONCLUSIONS

Depression and anxiety are not related to increased risk for most cancer outcomes, except for lung and smoking-related cancers. This study shows that key covariates are likely to explain the relationship between depression, anxiety, and lung and smoking-related cancers. PREREGISTRATION NUMBER: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=157677.

Baseline Severity as a Moderator of the Waiting List-Controlled Association of Cognitive Behavioral Therapy With Symptom Change in Social Anxiety Disorder: A Systematic Review and Individual Patient Data Meta-analysis

Importance

Social anxiety disorder (SAD) can be adequately treated with cognitive behavioral therapy (CBT). However, there is a large gap in knowledge on factors associated with prognosis, and it is unclear whether symptom severity predicts response to CBT for SAD.

Objective

To examine baseline SAD symptom severity as a moderator of the association between CBT and symptom change in patients with SAD.

Data Sources

For this systematic review and individual patient data meta-analysis (IPDMA), PubMed, PsycInfo, Embase, and the Cochrane Library were searched from January 1, 1990, to January 13, 2023. Primary search topics were social anxiety disorder, cognitive behavior therapy, and randomized controlled trial.

Study Selection

Inclusion criteria were randomized clinical trials comparing CBT with being on a waiting list and using the Liebowitz Social Anxiety Scale (LSAS) in adults with a primary clinical diagnosis of SAD.

Data Extraction and Synthesis

Authors of included studies were approached to provide individual-level data. Data were extracted by pairs of authors following the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline, and risk of bias was assessed using the Cochrane tool. An IPDMA was conducted using a 2-stage approach for the association of CBT with change in LSAS scores from baseline to posttreatment and for the interaction effect of baseline LSAS score by condition using random-effects models.

Main Outcomes and Measures

The main outcome was the baseline to posttreatment change in symptom severity measured by the LSAS.

Results

A total of 12 studies including 1246 patients with SAD (mean [SD] age, 35.3 [10.9] years; 738 [59.2%] female) were included in the meta-analysis. A waiting list-controlled association between CBT and pretreatment to posttreatment LSAS change was found (b = -20.3; 95% CI, -24.9 to -15.6; P < .001; Cohen d = -0.95; 95% CI, -1.16 to -0.73). Baseline LSAS scores moderated the differences between CBT and waiting list with respect to pretreatment to posttreatment symptom reductions (b = -0.22; 95% CI, -0.39 to -0.06; P = .009), indicating that individuals with severe symptoms had larger waiting list-controlled symptom reductions after CBT (Cohen d = -1.13 [95% CI, -1.39 to -0.88] for patients with very severe SAD; Cohen d = -0.54 [95% CI, -0.80 to -0.29] for patients with mild SAD).

Conclusions and Relevance

In this systematic review and IPDMA, higher baseline SAD symptom severity was associated with greater (absolute but not relative) symptom reductions after CBT in patients with SAD. The findings contribute to personalized care by suggesting that clinicians can confidently offer CBT to individuals with severe SAD symptoms.

Effectiveness of Self-guided Tailored Implementation Strategies in Integrating and Embedding Internet-Based Cognitive Behavioral Therapy in Routine Mental Health Care: Results of a Multicenter Stepped-Wedge Cluster Randomized Trial

BACKGROUND

Internet-based cognitive behavioral therapy (iCBT) services for common mental health disorders have been found to be effective. There is a need for strategies that improve implementation in routine practice. One-size-fits-all strategies are likely to be ineffective. Tailored implementation is considered as a promising approach. The self-guided integrated theory-based Framework for intervention tailoring strategies toolkit (ItFits-toolkit) supports local implementers in developing tailored implementation strategies. Tailoring involves identifying local barriers; matching selected barriers to implementation strategies; developing an actionable work plan; and applying, monitoring, and adapting where necessary.

OBJECTIVE

This study aimed to compare the effectiveness of the ItFits-toolkit with implementation-as-usual (IAU) in implementing iCBT services in 12 routine mental health care organizations in 9 countries in Europe and Australia.

METHODS

A stepped-wedge cluster randomized trial design with repeated measures was applied. The trial period lasted 30 months. The primary outcome was the normalization of iCBT delivery by service providers (therapists, referrers, IT developers, and administrators), which was measured with the Normalization Measure Development as a proxy for implementation success. A 3-level linear mixed-effects modeling was applied to estimate the effects. iCBT service uptake (referral and treatment completion rates) and implementation effort (hours) were used as secondary outcomes. The perceived satisfaction (Client Satisfaction Questionnaire), usability (System Usability Scale), and impact of the ItFits-toolkit by implementers were used to assess the acceptability of the ItFits-toolkit.

RESULTS

In total, 456 mental health service providers were included in this study. Compared with IAU, the ItFits-toolkit had a small positive statistically significant effect on normalization levels in service providers (mean 0.09, SD 0.04; P=.02; Cohen d=0.12). The uptake of iCBT by patients was similar to that of IAU. Implementers did not spend more time on implementation work when using the ItFits-toolkit and generally regarded the ItFits-toolkit as usable and were satisfied with it.

CONCLUSIONS

The ItFits-toolkit performed better than the usual implementation activities in implementing iCBT services in routine practice. There is practical utility in the ItFits-toolkit for supporting implementers in developing and applying effective tailored implementation strategies. However, the effect on normalization levels among mental health service providers was small. These findings warrant modesty regarding the effectiveness of self-guided tailored implementation of iCBT services in routine practice.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03652883; https://clinicaltrials.gov/ct2/show/NCT03652883.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1186/s13063-020-04686-4.

Usage Intensity of a Relapse Prevention Program and Its Relation to Symptom Severity in Remitted Patients With Anxiety and Depression: Pre-Post Study

BACKGROUND

Given that relapse is common in patients in remission from anxiety and depressive disorders, relapse prevention is needed in the maintenance phase. Although existing psychological relapse prevention interventions have proven to be effective, they are not explicitly based on patients' preferences. Hence, we developed a blended relapse prevention program based on patients' preferences, which was delivered in primary care practices by mental health professionals (MHPs). This program comprises contact with MHPs, completion of core and optional online modules (including a relapse prevention plan), and keeping a mood and anxiety diary in which patients can monitor their symptoms.

OBJECTIVE

The aims of this study were to provide insight into (1) usage intensity of the program (over time), (2) the course of symptoms during the 9 months of the study, and (3) the association between usage intensity and the course of symptoms.

METHODS

The Guided E-healTh for RElapse prevention in Anxiety and Depression (GET READY) program was guided by 54 MHPs working in primary care practices. Patients in remission from anxiety and depressive disorders were included. Demographic and clinical characteristics, including anxiety and depressive symptoms, were collected via questionnaires at baseline and after 3, 6, and 9 months. Log data were collected to assess the usage intensity of the program.

RESULTS

A total of 113 patients participated in the study. Twenty-seven patients (23.9%) met the criteria for the minimal usage intensity measure. The core modules were used by ≥70% of the patients, while the optional modules were used by <40% of the patients. Usage decreased quickly over time. Anxiety and depressive symptoms remained stable across the total sample; a minority of 15% (12/79) of patients experienced a relapse in their anxiety symptoms, while 10% (8/79) experienced a relapse in their depressive symptoms. Generalized estimating equations analysis indicated a significant association between more frequent face-to-face contact with the MHPs and an increase in both anxiety symptoms (β=.84, 95% CI .39-1.29) and depressive symptoms (β=1.12, 95% CI 0.45-1.79). Diary entries and the number of completed modules were not significantly associated with the course of symptoms.

CONCLUSIONS

Although the core modules of the GET READY program were used by most of the patients and all patients saw an MHP at least once, usage decreased quickly over time. Most patients remained stable while participating in the study. The significant association between the frequency of contact and the course of symptoms most likely indicates that those who received more support had more symptoms, and thus, it is questionable whether the support offered by the program was sufficient to prevent these patients from relapsing.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1186/s12888-019-2034-6.

Increasing demand for school counselling through a lay counsellor-delivered classroom sensitisation intervention: a stepped-wedge cluster randomised controlled trial in New Delhi, India

Introduction

We evaluated a classroom-based sensitisation intervention that was designed to reduce demand-side barriers affecting referrals to a school counselling programme. The sensitisation intervention was offered in the context of a host trial evaluating a low-intensity problem-solving treatment for common adolescent mental health problems.

Methods

We conducted a stepped-wedge, cluster randomised controlled trial with 70 classes in 6 secondary schools serving low-income communities in New Delhi, India. The classes were randomised to receive a classroom sensitisation session involving a brief video presentation and moderated group discussion, delivered by a lay counsellor over one class period (intervention condition, IC), in two steps of 4 weeks each. The control condition (CC) was whole-school sensitisation (teacher-meetings and whole-school activities such as poster displays). The primary outcome was the proportion of students referred into the host trial. Secondary outcomes were the proportion of students who met mental health caseness criteria and the proportion of self-referred adolescents.

Results

Between 20 August 2018 and 9 December 2018, 835 students (23.3% of all students) were referred into the host trial. The referred sample included 591 boys (70.8%), and had a mean age of 15.8 years, SD=0.06; 194 students (31.8% of 610 with complete data) met mental health caseness criteria. The proportion of students referred in each trial conditionwas significantly higher in the IC (IC=21.7%, CC=1.5%, OR=111.36, 95% CI 35.56 to 348.77, p<0.001). The proportion of self-referred participants was also higher in the IC (IC=98.1%, CC=89.1%, Pearson χ² (1)=16.92, p<0.001). Although the proportion of referred students meeting caseness criteria was similar in both conditions (IC=32.0% vs CC=28.1%), the proportion weighted for the total student population was substantially higher in the IC (IC=5.2%, CC=0.3%, OR=52.39, 95% CI 12.49 to 219.66, p<0.001).

Conclusion

A single, lay counsellor-delivered, classroom sensitisation session increased psychological help-seeking for common mental health problems among secondary school pupils from urban, low-income communities in India.

Trial registration number

NCT03633916.

Discontinuity of psychiatric care for patients with schizophrenia, relation to previous psychiatric care and practice variation between providers: a retrospective longitudinal cohort study

BACKGROUND

Patients with schizophrenia need continuous integrated healthcare, but many discontinue their treatment, often experiencing adverse outcomes. The first objective of this study is to assess whether patient characteristics or treatment history are associated with discontinuity of psychiatric elective care. The second objective is to assess whether practice variation between providers of psychiatric care contributes to discontinuity of elective care.

METHODS

A large registry-based retrospective cohort of 9194 schizophrenia patients, who were included if they received elective psychiatric care in December 2014-January 2015. Logistic regression models were used to identify predictive factors of discontinuity of care. The dependent variable was the binary variable discontinuity of care in 2016. Potential independent predictive variables were: age, sex, urbanization, and treatment history in 2013-2014. Practice variation between providers was assessed, adjusting for the case mix of patients regarding their demographic and care utilization characteristics.

RESULTS

12.9% of the patients showed discontinuity of elective psychiatric care in the follow-up year 2016. The risk of discontinuity of care in 2016 was higher in younger patients (between age 18 and 26), patients with a history of receiving less elective psychiatric care, more acute psychiatric care, more quarters with elective psychiatric care without antipsychotic medication, or receiving no elective treatment at all. No evidence for practice variation between providers was found.

CONCLUSIONS

Our findings show that the pattern of previous care consumption is an important prognostic factor of future discontinuity of elective care. We propose that previous care consumption can be used to design strategies to improve treatment retention and focus resources on those most at risk of dropping out.

Comprehensive database and individual patient data meta-analysis of randomised controlled trials on psychotherapies reducing suicidal thoughts and behaviour: study protocol

INTRODUCTION

Psychotherapy may reduce suicidal thoughts and behaviour, but its effectiveness is not well examined. Furthermore, conventional meta-analyses are unable to test possible effects of moderators affecting this relationship. This protocol outlines the building of a comprehensive database of the literature in this research field. In addition, we will conduct an individual patient data meta-analysis (IPD-MA) to establish the effectiveness of psychotherapy in reducing suicidality, and to examine which factors moderate the efficacy of these interventions.

METHODS AND ANALYSIS

To build a comprehensive database, randomised controlled trials examining the effect of any psychotherapy targeting any psychiatric disorder on suicidal thoughts or behaviour will be identified by running a systematic search in PubMed, Embase, PsycINFO, Web of Science, Scopus and The Cochrane Central Register of Controlled Trials from data inception to 12 August 2019. For the IPD-MA, we will focus on adult outpatients with suicidal ideation or behaviour. In addition, as a comparison group we will focus on a control group (waiting-list, care as usual or placebo). A 1-stage IPD-MA will be used to determine the effectiveness of psychotherapy on suicidal ideation, suicide attempts and/or suicide deaths, and to investigate potential patient-related and intervention-related moderators. Subgroup and sensitivity analyses will be conducted to test the robustness of the findings. Additionally, a conventional MA will be conducted to determine the differences between studies that provided IPD and those that did not. IPD-MA may determine the effectiveness of psychotherapy in reducing suicidality and provide insights into the moderating factors influencing the efficacy of psychotherapy. Answering these questions will inform mental healthcare practitioners about optimal treatments for different groups of individuals with suicidal ideation and/or behaviour and consequently help to reduce suicide risk.

ETHICS AND DISSEMINATION

An ethical approval is not required for this study. The results will be published in a peer-review journal.

PROSPERO REGISTRATION NUMBER

CRD42020140573.

Relation between pre-existing plaque size and neointimal healing in an adult porcine model of familial hypercholesterolemia

Background

Despite the efficacy of novel drug eluting stents (DES) in preventing restenosis, this complication still occurs, as do neo-atherosclerosis development and poor stent strut coverage that are associated with stent thrombosis. Safety and efficacy of novel coronary stents are preclinically being tested using an established porcine coronary model. However, the use of young healthy animal only allow limited conclusions to be drawn on the long-term effects, as the artieries do not reflect human pathology of advanced atherosclerosis. A key unresolved question is whether and how the presence, size and composition of pre-existing atherosclerotic plaque affect neointimal healing.

Purpose

The objective of this study is to understand the role of atherosclerotic plaque in neointimal response following DES placement in a large animal model of coronary artery disease by using optical coherence tomography (OCT) analysis.

Methods

The study was approved by the animal ethics committee. Familial hypercholesterolemia (FH) swine (n=6 Bretoncelles-Meishan) were given a high fat diet for 12 months to develop atherosclerosis. Stents (n=14) were implanted in n=14 coronary arteries under guidance of OCT with a stent-artery ratio of 1.1:1 at sites of atherosclerotic plaque, and animals were sacrificed after 28 days. Two types of Sirolimus eluting stents with different release profiles were implanted. Serial OCT pullbacks were taken before and after stent placement and after 28 days (follow-up), quantitatively analyzed and compared using dedicated software. The lumen area, stent area, plaque size (calculated as external elastic lamina (EEL) area - lumen area) and neointima (calculated as stent area – lumen area) were evaluated for each frame and averaged per stent. The plaque burden before stent implantation was evaluated at the same site of stent placement using coronary side branches as reference.

Results

The graph shows the association between the pre-existing plaque size before stenting and neointima formation after 28 days. Surprisingly, more pre-existing plaque size resulted in less neointima (P&lt;0.01). There was one outlier, a stent with long dissection and extensive malapposition at baseline which showed an excessive tissue response at follow-up. The response in this animal model shows similarity to human vessel response as both regions with thin neointima formation as well as poor strut coverage were observed for both stent types.

Conclusion

The novel model of adult FH swine shows long-term vessel response to DES, that is similar to human response. This work shows that pre-existing atherosclerotic plaque affects the neointima after DES implantation. This insight highlights the necessity to use relevant disease models for safety and efficacy testing.

Plaque size and neointima relation

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Netherlands Organisation for Health Research and Development (ZonMw)

Classification of comorbidity in obsessive-compulsive disorder: A latent class analysis

OBJECTIVE

Patients with OCD differ markedly from one another in both number and kind of comorbid disorders. In this study, we set out to identify and characterize homogeneous subgroups of OCD patients based on their comorbidity profile.

METHODS

In a cohort of 419 adult subjects with OCD, the lifetime presence of fifteen comorbid disorders was assessed. Latent class analysis was used to identify comorbidity-based subgroups. Groups were compared with regard to core clinical characteristics: familiality, childhood trauma, age at onset, illness severity, OCD symptom dimensions, personality characteristics, and course of illness.

RESULTS

The study sample could be divided in a large group (n = 311) with a low amount of comorbidity that could be further subdivided into two subgroups: OCD simplex (n = 147) and OCD with lifetime major depressive disorder (n = 186), and a group (n = 108) with a high amount of comorbidity that could be further subdivided into a general anxiety-related subgroup (n = 49), an autism/social phobia-related subgroup (n = 27), and a psychosis/bipolar-related subgroup (n = 10). Membership of the high-comorbid subgroup was associated with higher scores on childhood trauma, illness severity, and the aggression/checking symptom dimension and lower scores on several personality characteristics.

CONCLUSION

Grouping OCD patients based on their comorbidity profile might provide more homogeneous, and therefore, more suitable categories for future studies aimed at unraveling the etiological mechanisms underlying this debilitating disorder.

P3109Coronary vulnerable plaque development is promoted by multidirectional wall shear stress

Aim

Wall shear stress (WSS) has been widely associated with plaque development and destabilization. However, the multidirectionality of WSS, induced by the pulsatile nature of blood flow in combination with the arterial geometry, is rarely taken into account. The purpose of this study was to investigate the influence and predictive value of five (multidirectional) WSS parameters for coronary plaque progression and composition.

Methods

Familial hypercholesterolemic pigs (n=10, castrated male, 3 years old) were put on a high-fat diet and underwent imaging (near infrared spectroscopy-intravascular ultrasound (NIRS-IVUS), optical coherence tomography (OCT) and CT) of the three main coronary arteries at baseline and 10/12 months follow-up. IVUS-based lumen contours were combined with the centerline of artery as extracted from CT to obtain a 3D reconstruction of the coronary artery. Local flow velocity measurements were combined with the 3D-geometry of the coronary arterial lumen to calculate five multidirectional WSS parameters including: time average wall shear stress (TAWSS), oscilatory shear index (OSI), relative residence time (RRT), trans wall shear stress (TransWSS), cross flow index (CFI). For the analysis, arteries were divided into 3mm/45° sectors (n=3627). Per vessel each segment was classified as low, mid or high for each WSS metric based on the average value in the sector. Changes in wall thickness (WT) and plaque composition were assessed with NIRS-IVUS and OCT, and histology and related to the local (multidirectional) WSS.

Results

Half of the pigs developed lumen intruding, complex, lipid-rich plaques. In these pigs, coronary segments exposed to low baseline levels of TAWSS exhibited a significantly larger plaque growth per month compared to regions with either mid or high TAWSS (p<0.05, see figure). Furthermore, plaque growth correlated positively with the multidirectional WSS metrics OSI, RRT and CFI, with high multidirectionality resulting in the largest plaque growth (see figure). The positive predictive values (PPV) of the WSS metrics for plaque presence (WT>0.5mm) at follow up were 50% (low TAWSS), 48% (high OSI), 49% (high RRT), 47% (high CFI) and 43% (high transWSS). The PPVs for the presence of a fibroatheroma observed with histology were 61% (low TAWSS), 58% (high OSI), 61% (high RRT), 59% (high CFI) and 49% (high transWSS).

Plaque growth vs. multidirectional WSS

Conclusions

This study shows that both low and multidirectional WSS promote the development of large and complex coronary atherosclerotic plaques with vulnerable characteristics. The high predictive values for fibrous cap atheroma development demonstrate the potential of multidirectional WSS metrics as a predictive clinical marker for vulnerable disease.

Acknowledgement/Funding

ERC- starter grant (grant agreement 310457)

5222A distinct LDL profile to predict the risk of cardiovascular disease in familial hypercholesterolemia subjects: initial pre-clinical results

Aim

Cardiovascular disease development is highly variable between patients with familial hypercholesterolemia (FH). Since current risk prediction methods fail to estimate the risk of individual patients, all patients are treated with high-intensity lipid-lowering medication like statins and PCSK9-inhibitors. To prevent overtreatment (with its associated costs and side effects) of patients with a low risk, reliable biomarkers are urgently needed. While studying atherosclerosis development in an FH porcine model, we discovered a specific LDL profile that was directly associated with the severity of atherosclerosis development.

Methods

10 adult pigs with an LDLR mutation received a high-fat diet for 12 months. Atherosclerosis development in the three main coronary arteries was monitored with intravascular ultrasound (IVUS) and optical coherence tomography at three time points. After sacrifice, tissue was harvested for detailed histological analysis of the coronary plaque composition. Size-exclusion chromatography (SEC, n=10) and LC-MSMS (n=4) were used to assess the plasma lipoprotein profile, and the sphingolipid content of LDL, relative to cholesterol.

Results

Imaging and histology revealed a marked difference in pigs that developed large, lumen intruding plaques (IVUS-based plaque burden 13–77%) within 9 months (n=5) and pigs (n=5) that only developed early lesions (IVUS-based plaque burden 8–34%), even after 12 months of follow-up. The plaques seen in the fast responding pigs possessed distinct characteristics of advanced disease (i.e. heavy macrophage infiltration, large lipid-rich necrotic cores, neovascularisation, micro- and macrocalcifications and intraplaque haemorrhage, see figure). In these fast responders, fibrous cap atheroma occupied 34% of the total artery.

SEC revealed two distinct LDL subclasses: regular and “larger” LDL particles. Fast responding pigs with advanced atherosclerosis displayed a significantly higher ratio in cholesterol concentration of regular/'larger' LDL than slow responding pigs (1.7 (1.3–1.9) vs. 0.8 (0.6–1.2); (p=0.004), see figure). Compared to regular LDL, “larger” LDL contained relatively more sphingolipids in the fast responding than in the slow responding animals (regular LDL/'larger' LDL: S1P 0.5 (0.5–0.5) vs. 1.0 (0.8–1.2); Cer16:0 0.70 (0.67–0.73) vs. 1.04 (0.95–1.13); Cer18:0 0.60 (0.58–0.61) vs. 1.15 (1.13–1.16); Cer20:0 0.73 (0.73–0.74) vs. 0.94 (0.94–0.94)). “Larger” LDL particles and comparable sphingolipid ratios were also observed in FH patients. Cardiovascular data from our FH patient cohort, coupled to the LDL subclass distribution, will provide more insight into the potential of this novel biomarker.

Conclusion

A distinct difference in LDL subclasses, including a new “larger” LDL particle, was found in fast versus slow responding FH animals. This finding can potentially be used to identify FH patients at the highest risk of CVD to avoid overtreatement of low risk patients.

Acknowledgement/Funding

ERC- starter grant (grant agreement 310457)

P3588The synergistic effect of NIRS-detected lipid-rich plaque and 5 different multidirectional wall shear stress metrics on human coronary plaque growth

Introduction

Local wall shear stress (WSS) metrics, high local lipid levels (as detected by near-infrared spectroscopy (NIRS)), as well as systemic lipid levels, have been individually associated with atherosclerotic disease progression. However, a possible synergistic effect remains to be elucidated. This study is the first study to combine WSS metrics with NIRS-detected local lipid content to investigate a potential synergistic effect on plaque progression in human coronary arteries.

Methods

The IMPACT study is a prospective, single centre study investigating the relation between atherosclerotic plaque progression and WSS in human coronary arteries. Patients with ACS treated with PCI were included. At baseline and after 1-year follow-up, patients underwent near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) imaging and intravascular doppler flow measurements of at least one non-culprit coronary artery. After one month, a CT angiography was made. CT derived centreline combined with IVUS lumen contours resulted in a 3D reconstruction of the vessel. The following WSS metrics were computed using computational fluid dynamics applying the vessel specific invasive flow measurements: time-average wall shear stress (TAWSS), relative residence time (RRT), cross-flow index, oscillatory shear index and transverse wall shear stress. Low TAWSS is known as pro atherogenic, in contrast to all the other shear stress metrics, at which a high magnitude is pro-atherogenic. The arteries were divided into 1.5mm/45° sectors. Based on NIRS-IVUS, wall thickness change over time was determined and NIRS positive sectors detected. Furthermore, per vessel the shear stress was divided into tertiles (low, intermediate, high). To investigate the synergistic effect of local lipids on shear stress related plaque growth, wall thickness change over time was related to the different shear stress metrics comparing the NIRS-positive with the NIRS-negative sectors.

Results

15 non-culprit coronary arteries from the first 14 patients were analyzed (age 62±10 years old and 92.9% male). A total of 2219 sectors were studied (5.2%, N=130, NIRS-positive) for wall thickness changes. After studying all five shear stress metrics, we found for TAWSS and RRT that presence of lipids, as detected by NIRS, amplified the effect of shear stress on plaque progression (see figure). Sectors presenting with lipid-rich plaque, compared to NIRS-negative sectors, showed more progression when they were exposed to low TAWSS (p=0.07) or high RRT (p=0.012) and more regression in sectors exposed to high TAWSS (p=0.10) or low RRT (p=0.06).

Delta wall thickness vs shear stress

Conclusion

We presented the first preliminary results of the IMPACT study, showing the synergistic effect of lipid rich plaque and shear stress on plaque progression. Therefore, intravascular lipid-rich plaque (NIRS) assessment has added value to shear stress profiling for the prediction of plaque growth, leading to improved risk stratification.

Acknowledgement/Funding

ERC starting grant 310457

The effectiveness of a low-intensity problem-solving intervention for common adolescent mental health problems in New Delhi, India: protocol for a school-based, individually randomized controlled trial with an embedded stepped-wedge, cluster randomized controlled recruitment trial

BACKGROUND

Conduct, anxiety, and depressive disorders account for over 75% of the adolescent mental health burden globally. The current protocol will test a low-intensity problem-solving intervention for school-going adolescents with common mental health problems in India. The protocol also tests the effects of a classroom-based sensitization intervention on the demand for counselling services in an embedded recruitment trial.

METHODS/DESIGN

We will conduct a two-arm, individually randomized controlled trial in six Government-run secondary schools in New Delhi. The targeted sample is 240 adolescents in grades 9-12 with persistent, elevated mental health symptoms and associated distress/impairment. Participants will receive either a brief problem-solving intervention delivered over 3 weeks by lay counsellors (intervention) or enhanced usual care comprised of problem-solving booklets (control). Self-reported adolescent mental health symptoms and idiographic problems will be assessed at 6 weeks (co-primary outcomes) and again at 12 weeks post-randomization. In addition, adolescent-reported distress/impairment, perceived stress, mental wellbeing, and clinical remission, as well as parent-reported adolescent mental health symptoms and impact scores, will be assessed at 6 and 12 weeks post-randomization. We will also complete a parallel process evaluation, including estimations of the costs of delivering the interventions. An embedded recruitment trial will apply a stepped-wedge, cluster (class)-randomized controlled design in 70 classes across the six schools. This will evaluate the added effect of a classroom-based sensitization intervention over and above school-level sensitization activities on the primary outcome of referral rate into the host trial. Other outcomes will be the proportion of referrals eligible to participate in the host trial, proportion of self-generated referrals, and severity and pattern of symptoms among referred adolescents in each condition. Power calculations were undertaken separately for each trial. A detailed statistical analysis plan will be developed separately for each trial prior to unblinding.

DISCUSSION

Both trials were initiated on 20 August 2018. A single research protocol for both trials offers a resource-efficient methodology for testing the effectiveness of linked procedures to enhance uptake and outcomes of a school-based psychological intervention for common adolescent mental health problems.

TRIAL REGISTRATION

Both trials are registered prospectively with the National Institute of Health registry ( www.clinicaltrials.gov ), registration numbers NCT03633916 and NCT03630471 , registered on 16th August, 2018 and 14th August, 2018 respectively).

Profiling psychopathology of patients reporting early childhood trauma and emotional neglect: Support for a two-dimensional model?

OBJECTIVE

Profiling patients who report early childhood trauma and emotional neglect may be useful for treatment planning. This study attempts to quantify a two-dimensional "trauma-neglect model" (Draijer, 2003) proposed to distinguish clinical profiles in terms of trauma-related, dissociative, and personality pathology.

METHOD

A sample of patients referred to a trauma program (n = 49) and a personality disorders program (n = 101) was extensively assessed. Cluster analysis was used to discriminate patients in terms of "psychiatric disease burden," based on symptom severity scores, type of disorder, and level of maladaptive personality functioning. Clusters that differed in psychiatric disease burden were mapped in the trauma-neglect space and their positions were evaluated.

RESULTS

We found three clusters and labeled them as "mildly impaired" (26% of patients), "moderately impaired" (43% of patients), and "severely impaired" (31% of patients). The mean scores on trauma and neglect for the mild and severe groups differed significantly.

CONCLUSIONS

These findings indicate that further investigation of the validity of the model, which may be used to plan treatment, is useful. Patients experiencing a wide range of trauma-related disorders, dissociative disorders (DD), and personality disorders (PD), combined with a high level of psychiatric symptoms and a maladaptive style of personality functioning, report a range of traumatic experiences in combination with a lack of maternal care, and can be profiled as "severely impaired." (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Is self-guided internet-based cognitive behavioural therapy (iCBT) harmful? An individual participant data meta-analysis

BACKGROUND

Little is known about potential harmful effects as a consequence of self-guided internet-based cognitive behaviour therapy (iCBT), such as symptom deterioration rates. Thus, safety concerns remain and hamper the implementation of self-guided iCBT into clinical practice. We aimed to conduct an individual participant data (IPD) meta-analysis to determine the prevalence of clinically significant deterioration (symptom worsening) in adults with depressive symptoms who received self-guided iCBT compared with control conditions. Several socio-demographic, clinical and study-level variables were tested as potential moderators of deterioration.

METHODS

Randomised controlled trials that reported results of self-guided iCBT compared with control conditions in adults with symptoms of depression were selected. Mixed effects models with participants nested within studies were used to examine possible clinically significant deterioration rates.

RESULTS

Thirteen out of 16 eligible trials were included in the present IPD meta-analysis. Of the 3805 participants analysed, 7.2% showed clinically significant deterioration (5.8% and 9.1% of participants in the intervention and control groups, respectively). Participants in self-guided iCBT were less likely to deteriorate (OR 0.62, p < 0.001) compared with control conditions. None of the examined participant- and study-level moderators were significantly associated with deterioration rates.

CONCLUSIONS

Self-guided iCBT has a lower rate of negative outcomes on symptoms than control conditions and could be a first step treatment approach for adult depression as well as an alternative to watchful waiting in general practice.

Evaluation of an interaction-skills training for reducing the burden of family caregivers of patients with severe mental illness: a pre-posttest design

BACKGROUND

Family members who care for patients with severe mental illness experience emotional distress and report a higher incidence of mental illness than those in the general population. They report feeling inadequately prepared to provide the necessary practical and emotional support for these patients. The MAT training, an Interaction-Skills Training program (IST) for caregivers, was developed to meet those needs. This study used a single-arm pretest-posttest design to examine the impact of the training on caregivers' sense of competence (self-efficacy) and burden.

METHODS

One hundred family caregivers recruited from three mental health institutions participated in the training. Burden was assessed using the Involvement Evaluation Questionnaire, and self-efficacy using the Self-Efficacy Questionnaire. Analysis of variance with repeated measures was used to investigate whether participation in the training changed the level of family caregivers' burden and self-efficacy. Pearson's correlation was used to examine the relationships between self-efficacy and burden.

RESULTS

Our results indicate that, after the training, self-efficacy increased significantly over time (p < 0.001) and that burden decreased significantly (p < 0.001). However, the results could not demonstrate the expected association between an increase of self-efficacy and decrease of burden. Caregivers expressed high appreciation for the training.

CONCLUSIONS

After following the IST program, family caregivers of patients with severe mental illness experienced a greater sense of competence and a significant decrease in burden. The training was greatly appreciated and satisfied caregivers' need to acquire the skills required in complex caregiving situations.

TRIAL REGISTRATION

This study was retrospectively registered (14/01/2018) in the ISRCTN registry with study ID ISRCTN44495131 .

Efficacy of Self-guided Internet-Based Cognitive Behavioral Therapy in the Treatment of Depressive Symptoms: A Meta-analysis of Individual Participant Data

IMPORTANCE

Self-guided internet-based cognitive behavioral therapy (iCBT) has the potential to increase access and availability of evidence-based therapy and reduce the cost of depression treatment.

OBJECTIVES

To estimate the effect of self-guided iCBT in treating adults with depressive symptoms compared with controls and evaluate the moderating effects of treatment outcome and response.

DATA SOURCES

A total of 13 384 abstracts were retrieved through a systematic literature search in PubMed, Embase, PsycINFO, and Cochrane Library from database inception to January 1, 2016.

STUDY SELECTION

Randomized clinical trials in which self-guided iCBT was compared with a control (usual care, waiting list, or attention control) in individuals with symptoms of depression.

DATA EXTRACTION AND SYNTHESIS

Primary authors provided individual participant data from 3876 participants from 13 of 16 eligible studies. Missing data were handled using multiple imputations. Mixed-effects models with participants nested within studies were used to examine treatment outcomes and moderators.

MAIN OUTCOMES AND MEASURES

Outcomes included the Beck Depression Inventory, Center for Epidemiological Studies-Depression Scale, and 9-item Patient Health Questionnaire scores. Scales were standardized across the pool of the included studies.

RESULTS

Of the 3876 study participants, the mean (SD) age was 42.0 (11.7) years, 2531 (66.0%) of 3832 were female, 1368 (53.1%) of 2574 completed secondary education, and 2262 (71.9%) of 3146 were employed. Self-guided iCBT was significantly more effective than controls on depressive symptoms severity (β = -0.21; Hedges g  = 0.27) and treatment response (β = 0.53; odds ratio, 1.95; 95% CI, 1.52-2.50; number needed to treat, 8). Adherence to treatment was associated with lower depressive symptoms (β = -0.19; P = .001) and greater response to treatment (β = 0.90; P < .001). None of the examined participant and study-level variables moderated treatment outcomes.

CONCLUSIONS AND RELEVANCE

Self-guided iCBT is effective in treating depressive symptoms. The use of meta-analyses of individual participant data provides substantial evidence for clinical and policy decision making because self-guided iCBT can be considered as an evidence-based first-step approach in treating symptoms of depression. Several limitations of the iCBT should be addressed before it can be disseminated into routine care.

Effectiveness of a tailored implementation programme to improve recognition, diagnosis and treatment of anxiety and depression in general practice: a cluster randomised controlled trial

BACKGROUND

Anxiety and depression are not always diagnosed and treated in primary care as has been recommended. A tailored implementation programme, which addresses key barriers for change by targeted interventions, may help to remedy this.

METHODS

The effectiveness of an individually tailored implementation programme, additional to standardised training and feedback on the recognition and treatment of patients with anxiety or depression in general practice, was examined in a cluster randomised controlled trial. Participants were 46 general practitioners (GPs) from 23 general practices (12 intervention, 11 control) and 444 patients aged 18 years or older (198 intervention, 246 control) who screened positive on the extended Kessler 10. In the control group, GPs received a 1-day training in guidelines for recognition and stepped treatment for anxiety and depression. Ten months after the training session, GPs received feedback on their performance over the preceding 6 months. In the intervention group, GPs received the same training and feedback as those in the control condition; in addition, they were offered support, tailored to perceived local barriers to change. The support was delivered in the format of peer group supervisions and personalised telephone consultations. Data were based on an audit of patient records and patient surveys at baseline and after 3 and 6 months.

RESULTS

The tailored implementation programme led to recognition of a higher proportion of patients presenting with anxiety and depression (42% versus 31%; odds ratio (OR) = 1.60; 95% CI: 1.01-2.53), more consultations after recognition (IRR = 1.78; 95% CI: 1.14-2.78) and did not lead to more prescription of antidepressants (OR = 1.07; 95% CI: 0.52-2.19) or referral to specialist mental health services (OR = 1.62; 95% CI: 0.72-3.64). Patients in the intervention group reported better accessibility of care (effect size (ES) = 0.4; p < 0.05) and provision of information and advice (ES = 0.5; p < 0.05).

CONCLUSIONS

A tailored implementation programme may enhance the recognition and treatment of patients with anxiety or depression. Further development and evaluation of the programme is warranted to determine its cost-effectiveness.

TRAIL REGISTRATION

Dutch Trial Register identifier NTR1912 .

Clinical phenomenology of childhood abuse-related complex PTSD in a population of female patients: patterns of personality disturbance

OBJECTIVE

Complex posttraumatic stress disorder (PTSD) involves a variety of personality disturbances presumed to result from repeated interpersonal trauma such as child abuse. As Complex PTSD patients are a heterogeneous population, we searched for clinically relevant personality-based subtypes.

METHOD

This study used a cluster analysis of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV), Axis II features within a sample of 71 female outpatients with systematically assessed child abuse-related Complex PTSD.

RESULTS

Two main subtypes were found: adaptive and nonadaptive. The latter was further differentiated into withdrawn, alienated, suffering, and aggressive subtypes, characterized by different levels of introversion and disinhibition. Among the nonadaptive subtypes, the severity of Complex PTSD symptoms was lowest in the withdrawn (introverted only) subtype. The subtypes differed in their level of dissociation and depression but did not differ regarding PTSD symptoms, trauma history, or parental bonding characteristics.

CONCLUSION

Confirming earlier findings, our study found personality-based Complex PTSD subtypes, which could implicate differential treatment needs and results.

Effect of osmolality on net fluid absorption in non-infected and ETEC-infected piglet small intestinal segments

In the small intestinal segment perfusion model the effect of osmolality on net fluid absorption in enterotoxigenic Escherichia coli (ETEC)-infected and non-infected small intestinal segments of piglets was investigated. In ETEC-infected segments net fluid absorption was reduced. Lowering the osmolality from 375 to 150 mOsmol/l by reducing sodium chloride concentrations increased net fluid absorption. There was a linear relationship between osmolality and net fluid absorption for both non-infected and ETEC-infected segments. Below 150 mOsmol/l the inverse relationship between osmolality and net fluid absorption disappeared. Substitution of sodium chloride with mannitol decreased net fluid absorption since mannitol cannot be actively absorbed. In ETEC-infected segments perfused with oral rehydration solution net fluid absorption significantly increased compared to a sodium chloride solution of similar osmolality, probably because of the high glucose concentration. Supplying hypotonic sodium chloride fluids to piglets can be beneficial in replenishing water and electrolyte losses in case of infectious diarrhoea.

Escherichia coli F4 fimbriae specific llama single-domain antibody fragments effectively inhibit bacterial adhesion in vitro but poorly protect against diarrhoea

Oral administration of polyclonal antibodies directed against enterotoxigenic Escherichia coli (ETEC) F4 fimbriae is used to protect against piglet post-weaning diarrhoea. For cost reasons, we aim to replace these polyclonal antibodies by recombinant llama single-domain antibody fragments (VHHs) that can be produced efficiently in microorganisms. Six F4 fimbriae specific VHHs were isolated. The VHH that was produced at the highest level by yeast, K609, was further analysed. 3.8 mg/L K609 inhibited 90% of bacterial attachment to intestinal brush borders in vitro. Perfusion of a jejunal segment with at least 4 mg/L K609 reduced the ETEC-induced fluid loss, but only to 30%. Preventive administration of a high K609 dose (150 mg/(piglet day)) to piglets that were challenge infected with ETEC resulted in less severe diarrhoea only at 4 and 5 days post-infection, but did not improve average daily weight gain, ETEC shedding and piglet survival. Thus, we have shown that an antibody fragment that effectively inhibited in vitro ETEC adhesion to intestinal brush borders poorly protected piglets against experimental ETEC infection.

Effect of supplementary feeding during the sucking period on net absorption from the small intestine of weaned pigs

An intestinal perfusion technique was used to measure the effects of supplementary feeding (experiment 1) and temporary weaning (experiment 2) during the sucking period on the net absorption of fluid, sodium, chloride and potassium from the small intestine of pigs after weaning. The technique was also applied to control pigs which did not receive supplementary feed and were not temporarily weaned during the sucking period. Paired intestinal segments were prepared at five sites along the small intestine in each of 80 pigs in experiment 1 and 36 pigs in experiment 2. The cranial segment of each pair was infected with enterotoxigenic Escherichia coli (ETEC). In both experiments, four days after weaning, the net absorption of fluid, sodium and chloride in the uninfected segments was in general significantly less in all the pigs than at weaning or seven, 11 and 14 days after weaning and it was significantly greater in the pigs given supplementary feed than in the other pigs. Net absorption values in the infected segments of the control pigs were less four days after weaning than on the day of weaning. No differences were found between pigs that were temporarily weaned or not and those that were not fed during the sucking period. Supplementary feeding during the sucking period partially prevented the decrease of net absorption usually observed after weaning in uninfected and in ETEC-infected segments of intestine.

Effects of weaning and enterotoxigenic Escherichia coli on net absorption in the small intestine of pigs

The purpose of this study was to measure the net absorption of fluid, sodium, potassium and chloride in the small intestine of weaned pigs and of their unweaned littermates and to correlate these values with villus height and crypt depth. Five pairs of segments of the small intestine were prepared in each of 80 pigs; the cranial segment of each pair was injected with an enterotoxigenic strain of Escherichia coli and the caudal segment with a control solution. Net absorption was measured on the day of weaning and four, seven, 11 and 14 days after weaning. In unweaned pigs the net absorption of fluid, potassium and chloride did not vary with time. In weaned pigs the net absorption of fluid in the control segments was significantly less on days 4, 7 and 14 after weaning and of sodium and chloride on days 4 and 7 than in unweaned littermates. In infected segments of weaned pigs the net absorption of fluid was significantly less than in unweaned littermates on day 11 and 14, of sodium and potassium on day 11 and of chloride on days 4 and 11 after weaning. Net absorption was negatively correlated with villus height but only in the infected segments of weaned pigs; no other correlations were found. It was concluded that after weaning the net absorption of fluid and electrolytes in the small intestine of pigs is temporarily decreased, a condition that may initiate diarrhoea.

A long-term perfusion test to measure net absorption in the small intestine of weaned pigs

To study the effects of bacteria on net absorption of fluid and electrolytes in the small intestine of newly weaned pigs, a more comprehensive and ethical alternative to the ligated loop test was developed. Five paired segments, located at 10, 25, 50, 75 and 95 per cent sites along the small intestine, were cannulated at both ends and solutions perfused continuously through the segments for 10 hours. Net absorption was determined by both a volume method and a method using a non-absorbable marker. Net absorption of fluid, sodium, potassium and chloride was significantly less in segments infected with an enterotoxigenic Escherichia coli than in control segments. This method was superior to the ligated loop test because (i) it was performed entirely under anaesthesia, (ii) the small intestine did not distend during a test, (iii) net absorption was determined per cm2 and along the whole length of the small intestine. Net absorption determined by the nonabsorbable marker was significantly less than that determined by the volume method.

Villus height and crypt depth in weaned and unweaned pigs, reared under various circumstances in The Netherlands

The height of the villi and depth of the crypts in the small intestine were studied after weaning in pigs reared under various circumstances in the Netherlands. Pigs taken from herds with a long history of postweaning diarrhoea had in general significantly shorter villi and deeper crypts than their counterparts from a specific pathogen-free herd. Weaning was associated with villus shortening, crypt deepening and subsequent villus lengthening in pigs from the specific pathogen-free herd. Giving supplementary feed during the sucking period was beneficial in preventing shortening of the villi and this villus shortening was less severe when the crypts were deep at weaning, a condition that perhaps lessens the severity of postweaning diarrhoea.

Recruitment of myocardial work and metabolism in regionally stunned porcine myocardium

We characterized postischemic changes in myocardial metabolism and regional external work, as measured by the integral of left ventricular pressure-segment-length loops. In 12 anesthetized swine, the left anterior descending coronary artery (LAD) was occluded for 10 min and reperfused for 30 min for two successive cycles. Before ischemia, regional work was 16,920 +/- 5,630 mmHg-mm/min and after stunning, work was reduced to 50 +/- 14% (P < 0.05). At baseline, oxygen and lactate consumption were 4.80 +/- 1.40 and 1.02 +/- 0.46 mumol.min-1 x g-1, respectively, and after stunning they were reduced to 3.24 +/- 0.80 (P < 0.05) and 0.16 +/- 0.21 mumol.min-1 x g-1 (P < 0.05), respectively. The atria were then paced 50 beats/min higher than the reperfusion heart rate, during and without an infusion of dobutamine (2 micrograms.kg-1 x min-1). During dobutamine, both regional external work and oxygen consumption returned to 98% of preischemic values, but lactate utilization remained depressed. We conclude that regional external work and oxygen consumption remain coupled during inotropic stimulation after stunning, with a preferential shift toward nonlactate substrates.

Enteropooling in piglets induced by soya-peptone mediated via an increased biosynthesis of prostanoids

The enteropooling activity of soya-peptone was studied in germfree piglets. The enteropooling activity was restricted to the proximal part of the jejunum and was found to be blocked by aspirin. The hypothesis that soya-peptone acts via an increased biosynthesis/release of prostanoids was further studied using guinea-pig lung parenchyma. In this tissue soya-peptone induces the release of TXB2, which was inhibited by indomethacin (3 microM). The involvement of cholinergic, histaminergic and serotonergic pathways in the soya-peptone-mediated response was excluded, using antagonists. The conclusion was reached that soya-peptone can stimulate/modulate the biosynthesis of cyclic eicosanoids and that it exerts its enteropooling activity via the same mechanism in the jejunum of piglets.