COVID-19 Stroke Apical Lung Examination Study 2: a national prospective CTA biomarker study of the lung apices, in patients presenting with suspected acute stroke (COVID SALES 2)

BACKGROUND

Apical ground-glass opacification (GGO) identified on CT angiography (CTA) performed for suspected acute stroke was developed in 2020 as a coronavirus-disease-2019 (COVID-19) diagnostic and prognostic biomarker in a retrospective study during the first wave of COVID-19.

OBJECTIVE

To prospectively validate whether GGO on CTA performed for suspected acute stroke is a reliable COVID-19 diagnostic and prognostic biomarker and whether it is reliable for COVID-19 vaccinated patients.

METHODS

In this prospective, pragmatic, national, multi-center validation study performed at 13 sites, we captured study data consecutively in patients undergoing CTA for suspected acute stroke from January-March 2021. Demographic and clinical features associated with stroke and COVID-19 were incorporated. The primary outcome was the likelihood of reverse-transcriptase-polymerase-chain-reaction swab-test-confirmed COVID-19 using the GGO biomarker. Secondary outcomes investigated were functional status at discharge and survival analyses at 30 and 90 days. Univariate and multivariable statistical analyses were employed.

RESULTS

CTAs from 1,111 patients were analyzed, with apical GGO identified in 8.5 % during a period of high COVID-19 prevalence. GGO showed good inter-rater reliability (Fleiss κ = 0.77); and high COVID-19 specificity (93.7 %, 91.8-95.2) and negative predictive value (NPV; 97.8 %, 96.5-98.6). In subgroup analysis of vaccinated patients, GGO remained a good diagnostic biomarker (specificity 93.1 %, 89.8-95.5; NPV 99.7 %, 98.3-100.0). Patients with COVID-19 were more likely to have higher stroke score (NIHSS (mean +/- SD) 6.9 +/- 6.9, COVID-19 negative, 9.7 +/- 9.0, COVID-19 positive; p = 0.01), carotid occlusions (6.2 % negative, 14.9 % positive; p = 0.02), and larger infarcts on presentation CT (ASPECTS 9.4 +/- 1.5, COVID-19 negative, 8.6 +/- 2.4, COVID-19 positive; p = 0.00). After multivariable logistic regression, GGO (odds ratio 15.7, 6.2-40.1), myalgia (8.9, 2.1-38.2) and higher core body temperature (1.9, 1.1-3.2) were independent COVID-19 predictors. GGO was associated with worse functional outcome on discharge and worse survival after univariate analysis. However, after adjustment for factors including stroke severity, GGO was not independently predictive of functional outcome or mortality.

CONCLUSION

Apical GGO on CTA performed for patients with suspected acute stroke is a reliable diagnostic biomarker for COVID-19, which in combination with clinical features may be useful in COVID-19 triage.

The influence of n-3 polyunsaturated fatty acids on cognitive function in individuals without dementia: a systematic review and dose-response meta-analysis

BACKGROUND

Omega-3 polyunsaturated fatty acids (n-3 PUFA) have been suggested as a cognitive enhancing agent, though their effect is doubtful. We aimed to examine the effect of n-3 PUFA on the cognitive function of middle-aged or older adults without dementia.

METHODS

We reviewed randomized controlled trials of individuals aged 40 years or older. We systematically searched PubMed/MEDLINE, EMBASE, CINAHL, PsycINFO, and Cochrane Library databases. We used the restricted cubic splines model for non-linear dose-response meta-analysis in terms of the standardized mean difference with 95% confidence intervals.

RESULTS

The current meta-analysis on 24 studies (n 9660; follow-up 3 to 36 months) found that the beneficial effect on executive function demonstrates an upward trend within the initial 12 months of intervention. This effect is prominently observed with a daily intake surpassing 500 mg of n-3 PUFA and up to 420 mg of eicosapentaenoic acid (EPA). Furthermore, these trends exhibit heightened significance in regions where the levels of blood docosahexaenoic acid (DHA) + EPA are not very low.

CONCLUSIONS

Supplementation of n-3 PUFA may confer potential benefits to executive function among the middle-aged and elderly demographic, particularly in individuals whose dietary DHA + EPA level is not substantially diminished.

What is the impact of one's chronic illness on his or her spouse's future chronic illness: a community-based prospective cohort study

BACKGROUND

Integrating a joint approach to chronic disease management within the context of a couple has immense potential as a valuable strategy for both prevention and treatment. Although spousal concordance has been reported in specific chronic illnesses, the impact they cumulatively exert on a spouse in a longitudinal setting has not been investigated. We aimed to determine whether one's cumulative illness burden has a longitudinal impact on that of their spouse.

METHODS

Data was acquired from a community-based prospective cohort that included Koreans aged 60 years and over, randomly sampled from 13 districts nationwide. Data from the baseline assessment (conducted from November 2010 to October 2012) up to the 8-year follow-up assessment was analyzed from October 2021 to November 2022. At the last assessment, partners of the index participants were invited, and we included 814 couples in the analysis after excluding 51 with incomplete variables. Chronic illness burden of the participants was measured by the Cumulative Illness Rating Scale (CIRS). Multivariable linear regression and causal mediation analysis were used to examine the longitudinal effects of index chronic illness burden at baseline and its change during follow-up on future index and spouse CIRS scores.

RESULTS

Index participants were divided based on baseline CIRS scores (CIRS < 6 points, n = 555, mean [SD] age 66.3 [4.79] years, 43% women; CIRS ≥ 6 points, n = 259, mean [SD] age 67.7 [4.76] years, 36% women). The baseline index CIRS scores and change in index CIRS scores during follow-up were associated with the spouse CIRS scores (β = 0.154 [SE: 0.039], p < 0.001 for baseline index CIRS; β = 0.126 [SE: 0.041], p = 0.002 for change in index CIRS) at the 8-year follow-up assessment. Subgroup analysis found similar results only in the high CIRS group. The baseline index CIRS scores and change in index CIRS scores during follow-up had both direct and indirect effects on the spouse CIRS scores at the 8-year follow-up assessment.

CONCLUSIONS

The severity and course of one's chronic illnesses had a significant effect on their spouse's future chronic illness particularly when it was severe. Management strategies for chronic diseases that are centered on couples may be more effective.

Dietary Carotene Intake and Suicidal Ideation in Korean Females: Analysis of Data From the Korea National Health and Nutrition Examination Survey (2012, 2013, and 2015)

OBJECTIVE

The suicide rate in Korea was the highest among countries in the Organisation for Economic Co-operation and Development in 2019. In a previous study, higher intake of vegetables and fruits was associated with a lower risk of suicidal ideation, and carotene-rich fruits and vegetables lowered the risk of depression. This study aimed to examine the direct relationship between carotene intake and suicidal ideation, adjusting for the effect on depression.

METHODS

This study used data from the Korea National Health and Nutrition Examination Survey (KNHANES) conducted in 2012, 2013, and 2015. Carotene intake was assessed through a food intake frequency survey with a 24-hour recall. Suicidal ideation and depression were assessed using the mental health section of the KNHANES. We applied logistic regression to assess the relationship between carotene intake and suicidal ideation, adjusting for potential confounders.

RESULTS

A total of 5,480 females aged 19-64 years were included in this study. Carotene intake was significantly lower in the suicidal ideation group (3,034.5±1,756.4 μg/day) than in the nonsuicidal ideation group (3,225.4±1,795.1 μg/day) (p=0.015). We found a significant inverse association between carotene intake and the risk of suicidal ideation after adjusting for potential confounders (odds ratio=0.934, 95% confidence interval=0.873-0.999).

CONCLUSION

These results suggest that carotene intake may be inversely associated with the risk of suicidal ideation. Our findings may inform the development of new nutritional interventions to prevent increases in the risk of suicide worldwide.

Association Between Depressed Mood Changes and Physical Activity Among Adolescents Post COVID-19 Pandemic

Objectives

Following the coronavirus disease 2019 (COVID-19) pandemic, adolescents have experienced decreased physical activity and a decline in mental health. This study analyzed the association between changes in depressed mood after the COVID-19 pandemic and physical activity among adolescents.

Methods

The analysis was based on the results of the 17th Youth Health Behavior Online Survey conducted in 2021, which included 54848 middle and high school students in South Korea. Information on physical activity included low-intensity physical activity lasting >60 min/day, high-intensity physical activity, and strength training exercises. A logistic regression analysis was performed to evaluate the association between physical activity and changes in depression after the COVID-19 pandemic.

Results

After adjusting for sociodemographic characteristics and previous depression, adolescents who performed strength training exercises more than once per week had a 0.95-fold lower risk (odds ratio [OR]=0.948, 95% confidence interval [CI]=0.905-0.994, p= 0.027) of increasing depression after the COVID-19 pandemic, while the risk of decreasing depression increased by 1.22-fold (OR=1.215, 95% CI=1.131-1.305, p<0.001). The results were not significant for low-intensity physical activity for >60 min/day and high-intensity physical activity.

Conclusion

Strength-training exercises are significantly associated with the prevention of depression among adolescents following the COVID-19 pandemic.

Shared Risk Factors for Depressive Disorder Among Older Adult Couples in Korea

Importance

Although couples may share many risk factors for depressive disorders in their lifetime, whether these factors mediate the shared risk of depressive disorders has rarely been investigated.

Objectives

To identify the shared risk factors for depressive disorder in couples and investigate their mediating roles in the shared risk of depressive disorders among older adult couples.

Design, Setting, and Participants

This nationwide, multicenter, community-based cohort study assessed 956 older adults from the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD) and a cohort of their spouses (KLOSCAD-S) between January 1, 2019, to February 28, 2021.

Exposures

Depressive disorders of the KLOSCAD participants.

Main Outcomes and Measures

The mediating roles of shared factors in couples on the association between one spouse's depressive disorder and the other's risk of depressive disorders was examined using structural equation modeling.

Results

A total of 956 KLOSCAD participants (385 women [40.3%] and 571 men [59.7%]; mean [SD] age, 75.1 [5.0] years) and their spouses (571 women [59.7%] and 385 men [40.3%]; mean [SD] age, 73.9 [6.1] years) were included. The depressive disorders of the KLOSCAD participants were associated with an almost 4-fold higher risk of depressive disorders in their spouses in the KLOSCAD-S cohort (odds ratio, 3.89; 95% CI, 2.06-7.19; P < .001). Social-emotional support mediated the association between depressive disorders in the KLOSCAD participants and their spouses' risk of depressive disorders by itself (β = 0.012; 95% CI, 0.001-0.024; P = .04; mediation proportion [MP] = 6.1%) and through chronic illness burden (β = 0.003; 95% CI, 0.000-0.006; P = .04; MP = 1.5%). Chronic medical illness burden (β = 0.025; 95% CI, 0.001-0.050; P = .04; MP = 12.6%) and presence of a cognitive disorder (β = 0.027; 95% CI, 0.003-0.051; P = .03; MP = 13.6%) mediated the association.

Conclusions and Relevance

The risk factors shared by older adult couples may mediate approximately one-third of the spousal risk of depressive disorders. Identification of and intervention in the shared risk factors of depression among older adult couples may reduce the risk of depressive disorders in the spouses of older adults with depression.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Deep learning-based diagnosis of Alzheimer's disease using brain magnetic resonance images: an empirical study

The limited accessibility of medical specialists for Alzheimer's disease (AD) can make obtaining an accurate diagnosis in a timely manner challenging and may influence prognosis. We investigated whether VUNO Med-DeepBrain AD (DBAD) using a deep learning algorithm can be employed as a decision support service for the diagnosis of AD. This study included 98 elderly participants aged 60 years or older who visited the Seoul Asan Medical Center and the Korea Veterans Health Service. We administered a standard diagnostic assessment for diagnosing AD. DBAD and three panels of medical experts (ME) diagnosed participants with normal cognition (NC) or AD using T1-weighted magnetic resonance imaging. The accuracy (87.1% for DBAD and 84.3% for ME), sensitivity (93.3% for DBAD and 80.0% for ME), and specificity (85.5% for DBAD and 85.5% for ME) of both DBAD and ME for diagnosing AD were comparable; however, DBAD showed a higher trend in every analysis than ME diagnosis. DBAD may support the clinical decisions of physicians who are not specialized in AD; this may enhance the accessibility of AD diagnosis and treatment.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with prostate cancer

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of prostate cancer was published in 2020. It was therefore decided, by both the ESMO and the Singapore Society of Oncology (SSO), to convene a special, virtual guidelines meeting in November 2021 to adapt the ESMO 2020 guidelines to take into account the differences associated with the treatment of prostate cancer in Asia. These guidelines represent the consensus opinions reached by experts in the treatment of patients with prostate cancer representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate. The aim is to provide guidance for the optimisation and harmonisation of the management of patients with prostate cancer across the different regions of Asia.

Mood disorders increase mortality mainly through dementia: A community-based prospective cohort study

OBJECTIVE

The effects of mood disorders on mortality may be mediated by their effects on the risk of dementia, and interventions to reduce the occurrence of dementia may reduce their overall mortality. This study aimed to investigate the direct effects of depressive and bipolar disorders on the 6-year risk of mortality and also their indirect effects on mortality due to their effect on the risk of dementia.

METHODS

A total of 5101 Koreans were selected from a community-based prospective cohort study, and 6-year risks of mortality and dementia in participants with depressive and bipolar disorders were estimated by Cox proportional hazard analysis. The direct and indirect effects of depressive and bipolar disorders on the risk of mortality were estimated using structural equation modeling.

RESULTS

The depressive and bipolar disorder groups showed 51% and 85% higher 6-year mortality, and 82% and 127% higher risk of dementia, respectively, compared to euthymic controls. The effects of depressive and bipolar disorders on mortality were mainly mediated by their effects on the risk of dementia in a structural equation model. The direct effects of each mood disorder on mortality were not significant.

CONCLUSION

Both depressive and bipolar disorders increased the risks of mortality and dementia, and the effects of mood disorders on mortality were mainly mediated through dementia. As dementia occurs later in life than mood disorders, measures to prevent it may effectively reduce mortality in individuals with a history of mood disorders, as well as being more feasible than attempting to control other causes of death.

Vessel wall magnetic resonance and arterial spin labelling imaging in the management of presumed inflammatory intracranial arterial vasculopathy

Optimal criteria for diagnosing and monitoring response to treatment for infectious and inflammatory medium–large vessel intracranial vasculitis presenting with stroke are lacking. We integrated intracranial vessel wall MRI with arterial spin labelling into our routine clinical stroke pathway to detect presumed inflammatory intracranial arterial vasculopathy, and monitor disease activity, in patients with clinical stroke syndromes. We used predefined standardized radiological criteria to define vessel wall enhancement, and all imaging findings were rated blinded to clinical details. Between 2017 and 2018, stroke or transient ischaemic attack patients were first screened in our vascular radiology meeting and followed up in a dedicated specialist stroke clinic if a diagnosis of medium–large inflammatory intracranial arterial vasculopathy was radiologically confirmed. Treatment was determined and monitored by a multi-disciplinary team. In this case series, 11 patients were managed in this period from the cohort of young stroke presenters (<55 years). The median age was 36 years (interquartile range: 33,50), of which 8 of 11 (73%) were female. Two of 11 (18%) had herpes virus infection confirmed by viral nucleic acid in the cerebrospinal fluid. We showed improvement in cerebral perfusion at 1 year using an arterial spin labelling sequence in patients taking immunosuppressive therapy for >4 weeks compared with those not receiving therapy [6 (100%) versus 2 (40%) P = 0.026]. Our findings demonstrate the potential utility of vessel wall magnetic resonance with arterial spin labelling imaging in detecting and monitoring medium–large inflammatory intracranial arterial vasculopathy activity for patients presenting with stroke symptoms, limiting the need to progress to brain biopsy. Further systematic studies in unselected populations of stroke patients are needed to confirm our findings and establish the prevalence of medium–large artery wall inflammation.

321 Surgery Induction Guidebook – an Aid to a Successful Transition

Aim

There is a 4–12% increase in mortality following the August change over in the National Health Service (NHS) UK. A well-structured induction programme is mandatory to improve both the competency and confidence of new junior doctors. This activity was designed to evaluate and improve the induction process in Pilgrim Hospital by introducing an induction guidebook. It aimed to provide a sustainable and reliable source of information to junior doctors.

Method

An initial survey in the department assessed the needs and identified the information required for the guidebook. An induction guidebook was designed and circulated during the changeover. A feedback survey was conducted after the six months of the initial Induction guidebook release, to know the usefulness of components of the induction guidebook and identify any gaps to improve the guidebook.

Results

A total of 15 participants completed the feedback survey. 47% (7) found the induction guidebook beneficial and 53.3 % (8) found it ‘slightly beneficial'. Similarly, only 1 participant (6.7%) rated the guidebook to be “of minor importance”, while 53% (8) rating it “very important” part of induction. The feedback for the contents of the book was also encouraging with suggestions.

Conclusions

The guidebook proved to be a valuable source in helping new doctors during times of transition to adjust to the local system and improve the induction process. It provided information about local guidelines, job overview, team structure, IT, useful contacts, and other relevant information. We recommend the departmental guidebook as a vital part of local departmental induction during the changeover.

Vascular inflammation in patients with obstructive sleep apnoea and coronary artery disease shown on coronary computed tomography angiography attenuation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Obstructive sleep apnoea (OSA) is associated with increased plaque burden in coronary artery disease (CAD), but the role of vascular inflammation in this relationship is unclear. Coronary computed tomography angiography (CTA) enables surrogate assessment of systemic inflammation via subcutaneous adipose tissue attenuation (ScAT-a), and of coronary inflammation via epicardial adipose tissue volume and attenuation (EAT-v and EAT-a) and pericoronary adipose tissue attenuation (PCAT-a).

Purpose

To investigate whether vascular inflammation is increased in patients with severe OSA and high plaque burden.

Methods

Patients with clinically indicated polysomnography and coronary CTA were included. Severe OSA was classified as apnoea/hypopnoea index (AHI) &gt;30. High plaque burden was defined as a CT-Leaman score (CT-LeSc) &gt;8.3. Patients with both severe OSA and high plaque burden were defined as ‘Group 1’, all other patients were classified as ‘Group 2’. ScAT-a, EAT-a, EAT-v and PCAT-a were assessed on semi-automated software.

Results

A total of 91 patients were studied (59.3 ± 11.1 years). Severe OSA was associated with high plaque burden (p = 0.02). AHI correlated with CT-LeSc (r = 0.24, p = 0.023). Group 1 had lower EAT-a and PCAT-a compared to Group 2 (EAT-a: -87.6 vs. -84.0 HU, p = 0.01; PCAT-a: -90.4 vs. -83.4 HU, p &lt; 0.01). However, among patients without high plaque burden, EAT-a was increased in patients with severe OSA versus mild-moderate OSA (-80.3 vs. -84.0 HU, p = 0.020). On multivariable analysis, EAT-a independently associated with severe OSA and high plaque burden (p &lt; 0.02), and PCAT-a associated with severe OSA and high plaque burden, and hypertension (all p &lt; 0.01).

Conclusions

EAT attenuation is decreased in patients with severe OSA and high plaque burden but increased in patients with severe OSA and low plaque burden. These divergent results suggest coronary inflammation may be increased in OSA independent of CAD, but larger studies are required to validate these findings.

Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, treatment and follow-up of patients with renal cell carcinoma

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of renal cell carcinoma was published in 2019 with an update planned for 2021. It was therefore decided by both the ESMO and the Singapore Society of Oncology (SSO) to convene a special, virtual guidelines meeting in May 2021 to adapt the ESMO 2019 guidelines to take into account the ethnic differences associated with the treatment of renal cell carcinomas in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with renal cell carcinoma representing the oncological societies of China (CSCO), India (ISMPO), Japan (JSMO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug access restrictions in the different Asian countries. The latter were discussed when appropriate.

Exploration of Cognitive Outcomes and Risk Factors for Cognitive Decline Shared by Couples

Importance

Although couples could share many risk factors of cognitive disorders in their lifetime, whether shared risk factors mediate the shared risk of cognitive disorders has rarely been investigated.

Objective

To identify the risk factors of cognitive decline shared within couples and investigate their mediating roles in the shared risk of cognitive disorders and cognitive functions within couples.

Design, Setting, and Participants

A prospective cohort study was launched in November 1, 2010, and 784 participants were followed up every 2 years until December 31, 2020. This nationwide, multicenter, community-based study included older couples from the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD) and a cohort of their spouses (KLOSCAD-S).

Exposures

The cognitive disorder of a spouse was defined as mild cognitive impairment or dementia.

Main Outcomes and Measures

The mediating roles of factors shared within couples on the association between one spouse's cognitive disorder and the other's risk of cognitive disorders was examined with structural equation modeling.

Results

Included were 784 KLOSCAD participants (307 women [39.2%] and 477 men [60.8%]; mean [SD] age, 74.8 [4.8] years) and their spouses (477 women [60.8%] and 307 men [39.2%]; mean [SD] age, 73.6 [6.2] years). The cognitive disorder of the KLOSCAD participants was associated with almost double the risk of cognitive disorder of their spouses in the KLOSCAD-S cohort (odds ratio, 1.74; 95% CI, 1.12-2.69; P = .01). History of head injury (β = 0.50; 95% CI, 0.09-0.90; P = .02) and age (β = 2.57; 95% CI, 1.37-3.76; P < .001) mediated the association between cognitive disorder in the KLOSCAD participants and their spouses' risk of cognitive disorder. Physical inactivity mediated the association through major depressive disorder (β = 0.33, 95% CI, 0.09-0.57, P = .006 for physical inactivity; β = 0.28, 95% CI, 0.13-0.44, P < .001 for major depressive disorder). These factors similarly mediated the association between spousal cognitive disorder and cognitive functions such as memory and executive function.

Conclusions and Relevance

These findings suggest that the risk factors shared within couples may mediate approximately three-quarters of the spousal risk of cognitive disorders. Identification of and intervention in the shared risk factors of dementia within couples may reduce the risk of cognitive disorders in the spouses of people with dementia.

Association Between Suicide and Drinking Habits in Adolescents

Objectives

Adolescent suicide is a serious social problem. Adolescent alcohol use is one of the most important risk factors for adolescent suicide. This study aimed to identify the relationship between drinking habits and suicide among Korean adolescents.

Methods

Data from the 14th and 15th Korean Youth Risk Behavior Web-based Survey, conducted in 2018 and 2019, were used for analysis. Multiple logistic regression analysis was used to identify the relationship between drinking habits—including the age of drinking initiation, frequency of drinking, average drinking amount, frequency of drunkenness—and suicidal ideation, plans, and attempts.

Results

Even after adjusting for age, sex, school grade, academic achievement, socioeconomic status, depression, stress, and drinking habits, the frequencies of drinking and drunkenness increased the risk of suicide attempts. Suicide attempts were associated with the frequency of drinking in girls and middle school students, and with the frequency of drunkenness in boys and high school students.

Conclusion

This study identified associations between drinking habits (the age of drinking initiation, frequency of drinking, average amount of drinking, frequency of drunkenness) and suicidal behavior in adolescents. Our findings suggest that to prevent adolescent suicide, it might be necessary to investigate drinking habits, including the frequencies of drinking and drunkenness. Moreover, considering the differences in sex and school grade, it is important to include the individual group characteristics when evaluating drinking habits.

Estimation of unknown parameters using partially observed data

Purpose

This paper considers the complex stochastic systems such as supply chains, whose dynamics are controlled by an unknown parameter such as the arrival or service rates. The purpose of this paper is to provide a simulation-based estimator of the unknown parameter when only partially observed data on the underlying system is available.

Design/methodology/approach

The proposed method treats the unknown parameter as a random variable and estimates the parameter by computing the conditional expectation of the random variable given the partially observed data. This study then express the conditional expectation as a weighted sum of reverse conditional probabilities using Bayes’ rule. The reverse conditional probabilities are estimated using simulation.

Findings

The simulation studies indicate that the proposed estimator converges to the true value of the conditional expectation as the computer time allocated to the simulation increases. The proposed estimator is computed within a few seconds in all of the numerical examples, which demonstrates its time efficiency.

Originality/value

Most of the existing methods for estimating an unknown parameter require a significant amount of simulation, causing long computation delays. The proposed method requires a single simulation run for each candidate of the unknown parameter. Thus, it is designed to carry a significantly reduced computational burden. This feature will enable managers to use the proposed method when making real-time decisions.

Development of AI-powered imaging biomarker for breast cancer risk assessment on the basis of mammography alone

10519

Background: There is increasing interest in early detection of breast cancer by utilizing MRI in high-risk populations. However, it is still challenging to define and enrich the high-risk population. In this study, we developed an artificial intelligence (AI)-powered Imaging Biomarker in Mammography (IBM) to discover unique mammographic patterns, beyond simple density evaluations, that are related to breast cancer. Methods: A total of 49,577 mammography exams were collected to develop the AI-powered IBM, in which 6,218 were cancers. First, we evaluated the hypothesis that the unaffected breast of cancer patients would have a different pattern than that of non-cancer patients, by training AI (IBM-A) with unaffected breast in cancer patients and breasts of non-cancer patients. We then utilized further images of the cancer patients to train AI (IBM-B). This time we used both affected and unaffected breasts of cancer patients and breasts of non-cancer patients, allowing IBM-B to additionally learn patterns related to breast cancer. The IBMs were evaluated using the internal data (n = 2,058) that included 719 cancers. To demonstrate the feasibility of early detection by using IBM-B, it was tested with external data (n = 4,158) from an independent institution. This included pre-index exams (n = 292) taken prior to index exams acquired at the time of cancer diagnosis. Results: With the internal data, IBM-A showed AUC of 0.842, suggesting that AI could learn the difference between the normal breast of cancer patients and non-cancer patients. With IBM-B, which used additional cancer images to train, AUC was improved to 0.852. Based on the internal validation, IBM-B was chosen for the external validation, in which pre-index examinations were used only. IBM-B showed AUC of 0.777 in discriminating the pre-index exams of cancer patients and those of non-cancer patients. The radiologists excluded the apparent missed cancers (n = 87) by reviewing the pre-index exams retrospectively. After, the recalculated AUC of IBM-B was 0.770, suggesting that IBM-B can distinguish between mammograms of patients who will develop breast cancer in the future and those who will not. The mean IBM-B scores in pre-index exams of cancer group (0.580) were significantly higher than those in the normal (0.258, P < 0.001) and benign (0.258, P < 0.001) groups. Conclusions: AI-powered IBM could detect the unique parenchymal pattern associated with high breast cancer risks, and we show the potential of the AI-powered IBM to be used as an independent biomarker to select high-risk populations based on mammography alone.[Table: see text]

Association between Early Spermarche and Suicide Attempts in Boys: the Korea Youth Risk Behavior Web-based Survey

BACKGROUND

Puberty is a biologically and psychologically unstable period, and pubertal changes differ by sex. However, most previous studies on pubertal timing and suicide have focused on girls. This study investigated the association between early spermarche and suicide attempts in boys.

METHODS

We analyzed a nationally representative sample of Korean adolescents (The Korea Youth Risk Behavior Web-Based Survey, KYRBS) that included approximately 35,000 boys annually from 2011 to 2015. Pubertal timing in boys was defined by spermarche. Complex sampling logistic regression analyses were performed to evaluate the odds ratios (ORs) for suicide attempts between the early and average spermarche groups.

RESULTS

The ORs for suicide attempts in boys with early spermarche were significantly higher than those in boys with average spermarche after adjustment for age, perceived stress, depressive symptoms, and suicidal ideation. The ORs from 2011 to 2015 were as follows: 1.782 (P < 0.001), 1.490 (P = 0.002), 1.693 (P < 0.001), 1.541 (P = 0.001), and 1.393 (1.024-1.895; P = 0.035), respectively.

CONCLUSION

These findings suggest that early pubertal timing is a risk factor for suicide attempts in Korean boys after adjustment for depressive symptoms, perceived stress, and suicidal ideation, which have been previously reported as risk factors for suicide attempts. Therefore, careful attention should be paid to the prevention of suicide in boys who experience early spermarche in Korea.

Deep-learning analysis of CT imaging biomarker for PD-L1 expression to predict heterogeneous response to immune checkpoint inhibitors in non-small cell lung carcinoma

e21529

Background: Inter-tumoral genomic heterogeneity cause various immune status in tumor microenvironment, which may lead to indiscriminate response to immune checkpoint inhibitor (ICI) in patients with multiple lesions. Therefore, PD-L1 status from practically approachable, single lesion would not be always representative for immune status of whole metastatic lesions of a patient. To solve inter-tumoral heterogeneity issue before biopsy in clinic, we developed a deep-learning based CT biomarker for predicting PD-L1 status, then explored if the algorithm would also predict ICI response of multiple lesions in non-small cell lung carcinoma (NSCLC). Methods: Deep learning-based image analyzer was trained with CT images of NSCLC in Samsung Medical Center (SMC) (N = 104). Taking 3D patch of a lesion located by radiologists, 3D convolutional neural network was trained to predict PD-L1 (22C3 immunohistochemistry) tumor proportion score of each lung or lymph node lesion. The prediction model was validated using publicly available dataset (NSCLC Radiogenomics, N = 115). Finally, we applied the model to baseline CT who had multiple lesions (≥ 2) and also received ICI (SMC validation, N = 170). Tumor response was assessed based on RECIST 1.1, and discordant response was defined by best response of each lesion outside -10% ~ +10%. Results: Predicted PD-L1 score was positively correlated with real PD-L1 expression in NSCLC Radiogenomics (Pearson = 0.198, P= 0.0339). In SMC validation cohort, predicted PD-L1 score of each lesion was negatively correlated with ICI response of corresponding lesion (Pearson = -0.0941, P= 0.0325). Interestingly, 35 out of 170 (20.6%) patients showing discordant ICI response among lesions had worse progression free survival (PFS) (median PFS: 2.1m, 1.6m, 2.5m, and 18.7m in discordant response, concordant progress, stable, and regress, respectively, P< 0.001). Patients with discordant response had significantly wide-ranged predicted PD-L1 score compared with others (median range: 0.273 versus 0.185, P= 0.0079). Moreover, patient-level median of predicted PD-L1 scores of lesions was significantly associated with prolonged PFS (hazard ratio 0.69, P= 0.0401) and overall survival (hazard ratio 0.65, P= 0.0431). Conclusions: Deep-learning based imaging biomarker accurately predicts PD-L1 status of each metastasis, as well as independent ICI response reflecting inter-tumoral heterogeneity. This algorithm would guide which lesion would be representative in clinic.

Cyclin E1 and cyclin E2 in ER+ breast cancer: prospects as biomarkers and therapeutic targets

Cyclin E1 is one the most promising biomarkers in estrogen receptor positive (ER+) breast cancer for response to the new standard of care drug class, CDK4/6 inhibitors. Because of its strong predictive value, cyclin E1 expression may be used in the future to triage patients into potential responders and non-responders. Importantly, cyclin E1 is highly related to cyclin E2, and both cyclin E1 and cyclin E2 are estrogen target genes that can facilitate anti-estrogen resistance and can be highly expressed in breast cancer. However cyclin E1 and E2 are often expressed in different subsets of patients. This raises questions about whether the expression of cyclin E1 and cyclin E2 have different biological drivers, if high expressing subsets represent different clinical subtypes, and how to effectively develop a biomarker for E-cyclin expression. Finally, several pan-CDK inhibitors that target cyclin E-CDK2 activity have reached Phase II clinical trials. In this review, we outline the data identifying that different cohorts of patients have high expression of cyclins E1 and E2 in ER+ cancer and address the implications for biomarker and therapeutic development.

Model-Based High-Definition Dynamic Contrast Enhanced MRI for Concurrent Estimation of Perfusion and Microvascular Permeability

This work introduces a model-based, high-definition dynamic contrast enhanced (DCE) MRI for concurrent estimation of perfusion and microvascular permeability over the whole brain. A time series of reference-subtracted signals is decomposed into one component that reflects main contrast dynamics and the other one that includes residual contrast agents (CA) and background signals. The former is described by linear superposition of a finite number of basic vectors trained from an augmented set of data that consists of tracer-kinetic model driven signal vectors and patient-specific measured ones. Contrast dynamics is estimated by solving a constrained optimization problem that incorporates the linearized signal decomposition into the measurement model of DCE MRI and then combining the main component with the background-suppressed, residual CA signals. To the best of our knowledge, this is the first work that prospectively enables rapid temporal sampling with 1.5 s (3 ∼ 4 times higher than clinical routines) while simultaneously achieving high isotropic spatial resolution with 1.0 mm³ (4 ∼ 6 times higher than routines), enhancing estimation of both patient-specific inputs and outputs for quantification of microvascular functions. Simulations and experiments are performed to demonstrate the effectiveness of the proposed method in patients with brain cancer.