THU0058 ENHANCEMENT OF CARTILAGE REGENERATION EFFICIENCY WITH HUMAN ADIPOSE STEM CELL THREE-DIMENSIONAL SPHEROID

Background:

3D (three-dimensional) cell culture technology has been researched steadily because of its high potential of biocompatibility compared to single cells since 1990s, and is being developed to 3D spheroids recently. Spheroids are considered to reflect the natural organization of cells better than 2D cell cultures, and stem cells spheroids have been studied extensively in therapeutic transplantation. Stem cells were considered as a method of replacing autologous chondrocyte in regenerative treatment of articular cartilage. Compared to conventional single cells, 3D cell culture is artificially created an environment similar to a living body in vitro so that all cells collectively, a cell culture model that allows growth or interaction with the environment. Therefore, the findings of this study indicate that enhancement of treatment efficiency of stem cells caused by potential of survival and proliferation of hASC spheroid in Osteoarthritis. In conclusion, spheroid positive subpopulation of hASCs has high cell proliferation and survival but not apoptosis and cell death potential, which may contribute to successful cartilage regeneration and the development of stem cell therapies in the future.

Objectives:

Studied for 3D spheroids to investigate the mechanism of enhancement of survival and proliferationof hASC (human adipose stem cells) spheroid, which may contribute to successful improvement of therapeutic efficacy of stem cells.

Methods:

Cell isolation and culture / 3D cell culture dish preparation / hASCs culture on 3D cell culture dish / Real-time PCR analysis / Western blotting / Alcian blue staining / ACLT + MM (Anterior cruciate ligament transection with Medial meniscectomy) model / In vivo fluorescence for cell tracking / In vivo effects of spheroids in OA joint / Histological analysis / Enzyme-linked immunosorbent assay (ELISA) results for inflamma -tory cytokines in rat synovial fluid / Statistical Analysis

Results:

In order to see how the spheroid showed more residual than single, and how effective it was in actual cartilage regeneration, the result of paraffin tissues were confirmed by safranin O staining for each condition. The tendency of cartilage regeneration efficiency was good for spheroid. Although the differences between the single and spheroid groups were small, they reaffirmed that they could somewhat protect cartilage and help regeneration treatment. However, immunohistochemistry of HN(Human nucleic antigen) staining showed that cells of single and spheroid were not observed in the wound but disappeared by the paracrine effect.

Conclusion:

Spheroids do not exhibit differentiation characteristics, but they could be seen as a result of expression of related genes such as Bax, Bcl-XL and Alcian blue staining. Spheroids tend to have low potential of cell death rather than proliferation and reduction in the proliferation. So, we conclude the fact that instead of hASCs going directly to the surgical site to regenerate cartilage, they can help catrilage regeneration.

Acknowledgments:

This research was supported by the National Research Foundation of Korea (NRF-2019R1H1A2039685 and 2019R1I1A1A01043778).

Disclosure of Interests:

None declared

Preimplantation genetic diagnosis for retinoblastoma survivors: a cost-effectiveness study

This study aimed to investigate the cost-effectiveness of preimplantation genetic diagnosis (PGD) for the reproductive choices of patients with heritable retinoblastoma. The study modelled the costs of three cycles of in-vitro fertilization (IVF) and PGD across all uptake rates of PGD, number of children affected with retinoblastoma at each uptake rate and the estimated quality-adjusted life years (QALYs) gained. Cost-effectiveness analysis was conducted from the Australian public healthcare perspective. The intervention was the use of three cycles (one fresh and two frozen) of IVF and PGD with the aim of live births unaffected by the retinoblastoma phenotype. Compared with the standard care pathway (i.e. natural pregnancy), IVF and PGD resulted in a cost-saving to 18 years of age of AUD$2,747,294 for a base case of 100 couples with an uptake rate of 50%. IVF and PGD resulted in fewer affected (n = 56) and unaffected (n = 78) live births compared with standard care (71 affected and 83 unaffected live births), and an additional 0.03 QALYs per live birth. This modelling suggests that the use of IVF and PGD to achieve an unaffected child for patients with heritable retinoblastoma resulted in an overall cost-saving. There was an increase in QALYs per baby across all uptake rates. However, in total, fewer babies were born following the IVF and PGD pathway.

FRI0067 ALL-CAUSE AND CAUSE-SPECIFIC MORTALITY OF PATIENTS WITH RHEUMATOID ARTHRITIS IN KOREA: A NATION-WIDE POPULATION-BASED STUDY

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with excess mortality.

Objectives:

To compare all-cause and cause-specific mortality between RA patients versus general population, using a nationally representative cohort from Korea National Health Insurance Service database (KNHIS).

Methods:

Patients with RA aged ≥ 40 years were identified from 2010-2016 KNHIS database and their annual cohorts were constructed per each calendar year. RA patients of each cohort were required to have prevalent RA on January 1stof the given calendar year. The KNHIS were linked with Korea national mortality data to obtain cause of death information and to estimate expected deaths of RA patients in reference to mortality data of the general population in Korea. Standardized mortality ratio (SMR) with a 95% confidence interval (CI) was calculated to compare mortality of RA patients and general population.

Results:

A total of 6,404 deaths occurred among 79,440 RA patients during 2011-2016 period, showing all-cause SMR (95% CI) of 1.45 (1.42-1.49) compared to general population. The SMR was 1.72 (1.59-1.85) for biologics users and 1.43 (1.39-1.46) for non-users, versus general population. The annual SMR of RA patients showed a growing trend of mortality over time particularly among biologics users (Table 1). The SMRs for common causes of death among RA patients showed approximately tripled risk of dying due to pulmonary and infectious causes compared to general population (Table 2). There was approximately 20% increased risk of cardiovascular deaths but 8% decreased risk of cancer-related deaths among RA patients compared to general population (Table 2).

Table 1.

Annual all-cause SMR of RA patients compared to 2010 general population

Calendar year1RA patientsBiologics usersBiologics non-users20111.00 (0.92−1.07)1.13 (0.87−1.39)0.98 (0.90−1.06)20121.13 (1.06−1.21)0.98 (0.75−1.22)1.15 (1.07−1.23)20131.22 (1.14−1.30)1.29 (1.04−1.54)1.21 (1.13−1.29)20141.30 (1.23−1.38)1.53 (1.26−1.79)1.28 (1.20−1.36)20151.45 (1.38−1.53)1.81 (1.53−2.09)1.41 (1.33−1.50)20161.45 (1.37−1.52)1.94 (1.66−2.22)1.39 (1.31−1.47)

CI, confidence interval; RA, rheumatoid arthritis; SMR, standardized mortality ratio

12010 data were used to identify RA diagnosis dates but were not included for SMR estimation since diagnosis dates of RA were unclear for those who had RA in 2010.

Table 2.

Cause-specific SMR comparing RA patients versus general population

Cause of deathRA patientsBiologics usersBiologics non-usersInfection3.12 (2.93−3.13)4.12 (3.36−4.88)3.03 (2.83−3.23)Cancer0.92 (0.87−0.97)0.98 (0.81−1.14)0.91 (0.85−0.96)Respiratory13.14 (2.97−3.32)4.64 (3.89−5.38)3.01 (2.83−3.19)Cardiovascular21.18 (1.12−1.25)1.26 (1.03−1.50)1.18 (1.11−1.25)

CI, confidence interval; RA, rheumatoid arthritis; SMR, standardized mortality ratio

1Includes pulmonary infections and chronic lung diseases (J00-J98, U04);2Includes atherosclerotic and non-atherosclerotic deaths (I00-I99).

Conclusion:

The all-cause mortality of RA patients during 2011-2016 was overall 45% greater than that of general Korean population, which increased annually over the study period. The increased mortality was more prominent among biologics users than non-users. The risk of infectious and respiratory deaths were tripled among RA patients compared to general population.

References:

[1]Sokka T, et al. Mortality in rheumatoid arthritis: 2008 update. Clin Exp Rheumatol. 2008;26(5 Suppl 51):S35-61.

Acknowledgments:

None

Disclosure of Interests:

None declared

0800 Posttraumatic Stress Disorder and REM Sleep Without Atonia in Veterans

Introduction

In veterans, the prevalence of rapid eye movement (REM) sleep behavior disorder(RBD) is higher than the general population, and there is some evidence that this is related to posttraumatic stress disorder(PTSD). In addition, trauma related nightmares (TRNs) interfere with REM sleep and are often accompanied by motor activity. (rem sleep without atonia; RSWA). The purpose of this study is to determine whether the frequency of dream enactment behavior(DEB) and RSWA is different according to the presence of PTSD or trauma.

Methods

The patients (n = 2262) who underwent video assisted polysomnography (PSG) and sleep-related questionnaire surveys at Veteran Health Service Medical Center in Republic of Korea were reviewed retrospectively and cross-sectionally. Based on patients diagnosed with PTSD (N = 20; 100% male; 67.9 ± 8.5 years of age), those exposed to trauma but not diagnosed with PTSD (N = 23; 100% male; age 64.0 ± 13.4) and trauma unexposed controls (N = 21; 100% male; age 59.86 ± 10.9) were matched.

Results

In the PTSD group, patients who reported self-reported DEB tended to be more than the traumatic exposure group and the control group (P = 0.022). In-lab video assisted PSG showed no differences in DEB between the three groups, but RSWA. (p = 0.026) After adjusting for age, hypnotics, apnea hypopnea index (AHI), Beck depression inventory (BDI), and periodic limb movement (PLM) arousal factors, RSWA was significantly higher in the PTSD group than in the traumatic exposure group. (p = 0.006)

Conclusion

The result that RSWA was significantly higher in the PTSD group than in the traumatic exposure group suggests that there may be an associated pathophysiology between PTSD and RBD. Longitudinal studies are needed to establish the link between RBD with PTSD and neurodegenerative diseases associated with synucleinopathy.

Support

This study was supported by a VHS Medical Center Research Grant, Republic of Korea. (grant number: VHSMC 19033)

Effects of Cognitive Behavioral Group Program for Mental Health Promotion of University Students

This study aimed to explore the effects of a group cognitive behavioral program on depression, self-esteem, and interpersonal relations among undergraduate students. A non-equivalent control group pretest-posttest design was used. A convenient sample of 37 undergraduates (18 in the experimental group and 19 in the control group) at K university located in Changwon, South Korea was used. Data were collected from February 4, 2019 to June 18, 2019. The experimental group received eight sessions of the program, which were scheduled twice a week, with each session lasting 90 min. Collected data were analyzed using a chi-square test, Fisher’s exact test, independent t-test, and repeated measures ANOVA by SPSS/WIN 23.0 (SPSS, Inc., Chicago, IL, USA). The interaction of group and time was significant, indicating that the experimental group showed an improvement in depression, self-esteem, and personal relationship compared to the control group. A significant group by time interaction for depression, self-esteem, and personal relationship was also found between the two groups. The study results revealed that the group cognitive behavioral program was effective in reducing depression and improving self-esteem and interpersonal relation. Therefore, the group cognitive behavioral program can be used for promoting the mental health of students as well as for preventing depression in a university setting.

Long-distance optical pulling of nanoparticle in a low index cavity using a single plane wave

Optical pulling force (OPF) can make a nanoparticle (NP) move against the propagation direction of the incident light. Long-distance optical pulling is highly desired for nano-object manipulation, but its realization remains challenging. We propose an NP-in-cavity structure that can be pulled by a single plane wave to travel long distances when the spherical cavity wrapping the NP has a refractive index lower than the medium. An electromagnetic multipole analysis shows that NPs made of many common materials can receive the OPF inside a lower index cavity. Using a silica-Au core-shell NP that is encapsulated by a plasmonic nanobubble, we experimentally demonstrate that a single laser can pull the Au NP-in-nanobubble structure for ~0.1 mm. These results may lead to practical applications that can use the optical pulling of NP, such as optically driven nanostructure assembly and nanoswimmers.

Predictors and Barriers to Condom Use in the African Cohort Study

Consistent condom use is an inexpensive and efficacious HIV prevention strategy. Understanding factors associated with condom use and barriers to use can inform strategies to increase condom uptake. The ongoing African Cohort Study prospectively enrolls adults at 12 clinical sites in Uganda, Kenya, Tanzania, and Nigeria. At enrollment, participants are asked about condom use at last sex with a regular partner. Robust Poisson regression models were used to evaluate predictors of self-reported condom use. Participants who reported not using condoms were asked to provide reasons. From January 2013 to September 2019, 2482 participants reported having at least one regular sexual partner in the preceding 6 months. Of those, 1577 (63.5%) reported using a condom at last sex. Condom use was more common among older participants, males, HIV-infected participants, and those with an HIV-infected partner. Married participants, those with a partner of unknown HIV status, and those reporting alcohol use were less likely to report condom use at last sex. Condom use at last sex also varied significantly by clinical site. Partner disapproval or refusal to use a condom was a consistent driver of disparities in condom use among participants who were HIV infected, female, and aged 18-24 years. Effective HIV prevention programs should integrate condom education with the tools necessary to negotiate condom use with regular partners.

CRISPR-based gene editing enables FOXP3 gene repair in IPEX patient cells

The prototypical genetic autoimmune disease is immune dysregulation polyendocrinopathy enteropathy X-linked (IPEX) syndrome, a severe pediatric disease with limited treatment options. IPEX syndrome is caused by mutations in the forkhead box protein 3 (FOXP3) gene, which plays a critical role in immune regulation. As a monogenic disease, IPEX is an ideal candidate for a therapeutic approach in which autologous hematopoietic stem and progenitor (HSPC) cells or T cells are gene edited ex vivo and reinfused. Here, we describe a CRISPR-based gene correction permitting regulated expression of FOXP3 protein. We demonstrate that gene editing preserves HSPC differentiation potential, and that edited regulatory and effector T cells maintain their in vitro phenotype and function. Additionally, we show that this strategy is suitable for IPEX patient cells with diverse mutations. These results demonstrate the feasibility of gene correction, which will be instrumental for the development of therapeutic approaches for other genetic autoimmune diseases.

Association Between the Use of Benzodiazepines and the Occurrence of Acute Angle-closure Glaucoma in the Elderly: A Population-based Study

Introduction

Acute angle-closure glaucoma (AACG) is an ophthalmic emergency, accompanied with severe eye pain, headache, and visual changes because of acute intraocular pressure elevation. Among psychotropic drugs, several antidepressants, typical antipsychotics with strong anticholinergic effects, and topiramate have been known to increase a possibility of AACG. Benzodiazepines have been used widely in the treatment of mental and physical illnesses regardless of age or indication. Since benzodiazepines have some anticholinergic properties and affect pupillae muscles, their use could be theoretically a risk factor for AACG. However, it is unclear whether benzodiazepines actually increase the risk of AACG. To our knowledge, there was no population-based study on the risk of benzodiazepines to the occurrence of AACG.

Objectives/aims

To know whether benzodiazepines increase the risk of AACG in a geriatric population.

Methods

We will perform a case-control study using a geriatric cohort from the National Health Insurance database. Case subjects will be defined as cases diagnosed with AACG confirmed by the claim data of laser iridotomy, which is the definitive treatment of AACG. The controls, which were not diagnosed with AACG, will be matched with case subjects according to similar age, sex, and the scores of the Charlson comorbidity index.

Results

The data handling and statistical analyses will be executed in autumn and winter 2016.

Conclusions

Any preliminary findings of this study will be presented at the EPA 2017. We will discuss the importance of a pharmaco-epidemiological study in the geriatric research.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Education and devices to prevent blood and body fluid exposures

BACKGROUND

Healthcare workers are at risk of blood and body fluid exposures (BBFE) while delivering care to patients. Despite recent technological advances such as safety-engineered devices (SEDs), these injuries continue to occur in healthcare facilities worldwide.

AIMS

To assess the impact of an education and SEDs workplace programme on rates of reported exposures.

METHODS

A retrospective cohort study, utilizing interrupted time series analysis to examine reported exposures between 2005 and 2015 at a 600-bed hospital in Perth, Western Australia. The hospital wards were divided into four cohorts.

RESULTS

A total of 2223 records were available for analysis. The intervention was most effective for the first cohort, with significant improvements both short-term (reduction of 12 (95% CI 7-17) incidents per 1000 full-time equivalent (FTE) hospital staff) and long-term (reduction of 2 (CI 0.6-4) incidents per 1000 FTE per year). Less significant or consistent impacts were observed for the other three cohorts. Overall, the intervention decreased BBFE exposure rates at the hospital level from 19 (CI 18-20) incidents per 1000 FTE pre-intervention to 11 (CI 10-12) incidents per 1000 FTE post-intervention, a 41% reduction. No exposures resulted in a blood-borne virus infection.

CONCLUSIONS

The intervention was most effective in reducing exposures at a time when incidence rates were increasing. The overall effect was short-term and did not further reduce an already stabilized trend, which was likely due to improved safety awareness and practice, induced by the first cohort intervention.

A169 DEVELOPMENT OF A DECISION TOOL TO IMPROVE UTILISATION OF RECOMMENDED SURVEILLANCE INTERVALS FOR INDIVIDUALS WITH COLORECTAL POLYPS: A FOCUS GROUP ANALYSIS

Background

Several studies have demonstrated a high utilization of colonoscopy at shorter and longer time intervals than guideline recommendations. Innovative methods are required to increase adherence to recommended timing.

Aims

1) Explore current approaches used by endoscopist (EPs) and primary care providers (PCPs) to determine and communicate colonoscopy surveillance intervals (SI) between EPs, PCPs, and patients.

2) Obtain feedback for refining a decision tool to facilitate recommended SI.

3) Determine participant agreement of recommended SIs with current guidelines.

Methods

We conducted 4 focus groups (FGs); 3 FGs included EPs (n=12) and EPs in training (n=6); 1 FG included PCPs (n=4). FG questions explored use of guidelines, communication and follow-up practices with PCPs, EPs and patients, and challenges to follow-up.

Participants were also asked for feedback about a prototype polyp SI decision tool that was developed using an algorithm synthesizing current Canadian Association of Gastroenterology, US Multisociety Task Force, and expert panel guidelines on SI. FGs were audio-recorded and transcribed for qualitative content analysis. FGs were analysed separately, then compared for similarities and differences. Finally, participants individually made interval recommendations for 7 common endoscopy scenarios. Responses were analyzed for agreement with the guidelines used to develop the decision tool.

Results

EPs reported not routinely referring to guidelines and were confident in their memory of the intervals although some reported checking occasionally. Many indicated they may use the tool in a web based or mobile application for more complicated scenarios, although some would never use it. Concerns regarding the tool included being up to date with research evidence and having required data to input on hand. PCPs reported the tool may be useful as a communication aid to involve patients in decision making. A challenge noted in all FGs was role confusion regarding communicating, tracking, and scheduling patients’ future procedures on time.

Analysis of EPs (n=9) responses to the 7 scenarios showed that percent agreement with guidelines was low: 44% scored below 50% correct. Participants with the highest agreement scored 6/7; responses with the lowest agreement scored 0/7. The most common score was 3/7.

Conclusions

EPs appeared to be overconfident in their recommendations, but many were open to trying a website or mobile application decision tool to make evidence-based colonoscopy SI recommendations. Understanding, among PCPs and EPs, regarding responsibility for communicating results and scheduling follow-up surveillance for patients was inconsistent. Participant feedback informed development of a mobile application that is currently being pilot tested.

Funding Agencies

Research Manitoba

A244 MATERNAL THIOPURINE AND ANTI-TUMOR NECROSIS FACTOR THERAPY DURING PREGNANCY IS ASSOCIATED WITH AN INCREASED RISK OF PLACENTAL-RELATED DISEASES

Background

Though previous studies have suggested that most therapies for inflammatory bowel disease (IBD) are safe during pregnancy, the effect of these medications on placental-related diseases remain unknown.

Aims

To determine the effect of gestational medication exposure on pregnancy-related outcomes in patients with IBD.

Methods

We retrospectively reviewed the University of Alberta and University of Toronto pregnancy databases to identify patients (age > 18) who underwent routine assessment by a gastroenterologist at least once during pregnancy (first trimester (T1), second trimester (T2), and third trimester (T3). Pregnancy-related outcomes (maternal, obstetrical, and neonatal) were recorded from obstetrical records. Low-birth weight (LBW) was defined as an infant weight < 2500g at birth. Pre-term delivery was defined as birth < 37 weeks gestation. Medication exposure, such as 5-aminosalicylates (5-ASA), thiopurines, steroids, and anti-tumor necrosis factor (TNF) therapy was recorded for each trimester. Categorical variables were statistically compared using the Chi-square (x2) test through the SPSS software.

Results

A total of 84 patients were included. Compared to those not exposed to thiopurines, patients exposed to thiopurine therapy during T2 had an increased risk of pre-term birth (26.7% vs. 7.7%, p=0.046) and pre-eclampsia (13.3% vs. 0%, p=0.008) and a trend towards an increased risk of placental abruption (6.7% vs, 0%, p=0.061). Furthermore, compared to those not treated with corticosteroids, those prescribed corticosteroid therapy during any trimester had an increased risk of pre-term birth (T1 exposure: 50% vs. 10.2%, p=0.024; T2 exposure: 37.5% vs. 8.5%. p=0.018; T3 exposure: 42.9% vs. 8.8%, p=0.008) and infants born with LBW (T1 exposure: 50.0% vs. 7.8%, p=0.009; T2 exposure: 37.5% vs. 8.2%, p=0.015; T3 exposure: 57.1% vs. 8.6%, p=0.0005). Those exposed to corticosteroids in T3 only had an increased risk of PPROM (60.0% vs. 7.5%, p=0.0003) and chorioamnionitis (14.3% vs. 0%, p=0.002). Finally, anti-TNF therapy in T2 was associated with an increased risk of pre-eclampsia (9.1% vs. 0%, p=0.040. 5-ASA therapy was not associated with an increased risk of any adverse pregnancy-related outcome. No medication increased the risk of other maternal (i.e. gestational diabetes, emergency Cesarean-section delivery) and neonatal (intensive care unit admission, congenital anomalies) outcomes.

Conclusions

Placental related diseases, such as pre-eclampsia, appear to be increased with maternal exposure to thiopurine and anti-TNF therapy during pregnancy. Larger studies are required to confirm these associations.

Funding Agencies

None

Clinical and Laboratory Findings of Barley Allergy in Korean Children: a Single Hospital Based Retrospective Study

BACKGROUND

Barley is a grain that is consumed in various forms in Asia. Studies on barley allergy are limited to a few case reports about hypersensitivity reactions to beer, but there is no barley allergy study in children. This study aimed to identify the phenotype and immunologic findings in Korean children with barley allergy.

METHODS

Forty-two participants with a history of ingesting barley who underwent serum specific immunoglobulin E to barley (barley-sIgE) assay at the Department of Pediatrics in Ajou Medical Center were enrolled through a retrospective analysis of medical records from March 2008 to February 2018. The demographic characteristics, symptoms, and immunologic parameters of the patients were assessed.

RESULTS

Twenty subjects presented with clinical barley allergy (B-allergic group), and 22 were atopic controls without allergic reactions after the ingestion of barley (B-tolerant group). The median ages of the B-allergic and B-tolerant groups were 1 and 3 years, respectively. In the B-allergic group, the cutaneous system (90.0%) was most frequently affected, followed by the respiratory system (40.0%). Anaphylaxis was observed in 35.0% of the B-allergic group. The median level of barley-sIgE was 13.90 kU_A/L (range, 0.14-101.00 kU_A/L) in the B-allergic group, and this value was significantly higher (P < 0.001) than that of the B-tolerant group (0.30 kU_A/L; range, 0.01-24.40 kU_A/L), with an optimal cutoff level of 1.24 kU_A/L (sensitivity, 85.0%; specificity, 86.4%). A positive correlation was found between the serum levels of barley-sIgE and wheat-sIgE in the B-allergic group with clinical wheat allergy.

CONCLUSION

Barley is an important allergen for children in Korea. This study showed the clinical characteristics of barley allergy and suggested optimal cut-off levels of barley-sIgE for clinical barley allergy. Clinically, cross-reactivity or co-sensitization is often observed between barley and wheat.

Liquid Chromatographic Determination of Glyphosate in Water-Soluble Granular Formulations: Collaborative Study

A liquid chromatographic (LC) method for the determination of glyphosate in various water-soluble granular formulations was tested by 28 laboratories. Samples were dissolved in mobile phase and injected directly into an LC system with a 25 cm SAX column and a mobile phase of 96% aqueous buffer solution, 0.0062M KH2PO4, and 4% methanol. Detection was by UV absorption at 195 nm. Manual or automated injections were made via fixed-volume loops. Calculations were based on peak area comparisons with external standards. The collaborative study analyzed 5 matched pairs of 4 water-soluble granular formulations, with one determination per sample. The study generated 138 matched pairs, which were analyzed by using the AOAC spreadsheet and Youden’s matched-pair calculations. Coefficients of variation for the 4 formulations ranged from 0.65 to 1.37%. The LC method for the determination of glyphosate in water-soluble granular formulations has been adopted first action by AOAC INTERNATIONAL.

P783 Global longitudinal strain detects trastuzumab induced cardiotoxicity early in a clinical population

Background

Trastuzumab is highly effective in the treatment of breast cancer, and is often used as an adjuvant therapy. Due to its potential cardiotoxicity, serial monitoring of cardiac function is vital. Ejection fraction (EF) by two-dimensional echocardiography is routinely used but has limitations in measurement variability. Myocardial deformation imaging, in particular Global Longitudinal Strain (GLS), can detect pre-clinical myocardial dysfunction. However, its use is not yet adopted into routine clinical practice.

Aims

Our aim was to ascertain if a clinically significant reduction in GLS (≥11% from baseline) occurred before the onset of EF reduction, in patients who developed cardiotoxicity whilst receiving trastuzumab.

Methods

Between January 2014 and January 2019, 235 consecutive patients received trastuzumab and underwent serial echocardiography at 3 monthly intervals at our institute. Cardiotoxicity is defined as a ≥10% EF reduction from baseline or an EF &lt;50%. Women who developed cardiotoxicity as defined by this change in EF were retrospectively studied.

Two-dimensional speckle tracking was used to derive peak longitudinal strain in each myocardial segment from the apical four-, three- and two-chamber view images. GLS was taken as the average value of all these segments. The median time to ≥11% GLS reduction and ≥10% EF reduction or EF &lt;50% was compared.

Results

Thirteen women (mean age 53 ± 9.5 years) developed cardiotoxicity. EF was 61.8 ± 4.4% at baseline and 45.7 ± 7.5% following therapy (p = 0.00). A ≥11% reduction in GLS from baseline was observed in all patients: GLS -20.2 ± 1.5% and -15.6 ± 2.1%, p = 0.00. The median time to cardiotoxicity as defined by EF and GLS was 6 months and 3 months, respectively (p = 0.031), as shown in Table 1. Repeatability analysis showed both EF and GLS measurements in our cohort have good measurement reproducibility. Inter-observer intraclass correlation (ICC) for EF and GLS were 0.912 and 0.913, respectively. Intra-observer ICC for EF and GLS were 0.925 and 0.900, respectively.

Conclusion

Cardiotoxicity developed in a significant portion (6%) of our patients receiving trastuzumab. As a reduction in GLS was detectable early and preceded that of EF by 3 months, this may represent a therapeutic window for initiation of cardio-protective medication, if and when the use of GLS is incorporated into routine practice for cardiotoxicity surveillance.

Table 1: Summary of Findings. Baseline Cardiotoxicity Paired t-test p value Median time of onset EF 61.8 ± 4.4% 45.7 ± 7.5% P &lt; 0.01 6 months* GLS -20.2 ± 1.5% -15.6 ± 2.1% P &lt; 0.01 3 months* *denotes exact sign-test p &lt; 0.05.