Metabolic phenotyping with computed tomography deep learning for metabolic syndrome, osteoporosis and sarcopenia predicts mortality in adults

BACKGROUND

Computed tomography (CT) body compositions reflect age-related metabolic derangements. We aimed to develop a multi-outcome deep learning model using CT multi-level body composition parameters to detect metabolic syndrome (MS), osteoporosis and sarcopenia by identifying metabolic clusters simultaneously. We also investigated the prognostic value of metabolic phenotyping by CT model for long-term mortality.

METHODS

The derivation set (n = 516; 75% train set, 25% internal test set) was constructed using age- and sex-stratified random sampling from two community-based cohorts. Data from participants in the individual health assessment programme (n = 380) were used as the external test set 1. Semi-automatic quantification of body compositions at multiple levels of abdominal CT scans was performed to train a multi-layer perceptron (MLP)-based multi-label classification model. External test set 2 to test the prognostic value of the model output for mortality was built using data from individuals who underwent abdominal CT in a tertiary-level institution (n = 10 141).

RESULTS

The mean ages of the derivation and external sets were 62.8 and 59.7 years, respectively, without difference in sex distribution (women 50%) or body mass index (BMI; 23.9 kg/m2). Skeletal muscle density (SMD) and bone density (BD) showed a more linear decrement across age than skeletal muscle area. Alternatively, an increase in visceral fat area (VFA) was observed in both men and women. Hierarchical clustering based on multi-level CT body composition parameters revealed three distinctive phenotype clusters: normal, MS and osteosarcopenia clusters. The L3 CT-parameter-based model, with or without clinical variables (age, sex and BMI), outperformed clinical model predictions of all outcomes (area under the receiver operating characteristic curve: MS, 0.76 vs. 0.55; osteoporosis, 0.90 vs. 0.79; sarcopenia, 0.85 vs. 0.81 in external test set 1; P < 0.05 for all). VFA contributed the most to the MS predictions, whereas SMD, BD and subcutaneous fat area were features of high importance for detecting osteoporosis and sarcopenia. In external test set 2 (mean age 63.5 years, women 79%; median follow-up 4.9 years), a total of 907 individuals (8.9%) died during follow-up. Among model-predicted metabolic phenotypes, sarcopenia alone (adjusted hazard ratio [aHR] 1.55), MS + sarcopenia (aHR 1.65), osteoporosis + sarcopenia (aHR 1.83) and all three combined (aHR 1.87) remained robust predictors of mortality after adjustment for age, sex and comorbidities.

CONCLUSIONS

A CT body composition-based MLP model detected MS, osteoporosis and sarcopenia simultaneously in community-dwelling and hospitalized adults. Metabolic phenotypes predicted by the CT MLP model were associated with long-term mortality, independent of covariates.

Time to presentation and mortality outcomes among patients with diabetes and acute myocardial infarction

BACKGROUND/AIMS

Due to limited real-world evidence on the association between time to presentation (T2P) and outcomes following acute myocardial infarction and diabetes (AMI-DM), we investigated the characteristics of patients with AMI-DM and their outcomes based on their T2P.

METHODS

4,455 patients with AMI-DM from a Korean nationwide observational cohort (2011-2015) were divided into early and late presenters according to symptom-to-door time. The effects of T2P on three-year all-cause mortality were estimated using inverse probability of treatment weighting (IPTW) and survival analysis.

RESULTS

The incidence of all-cause mortality was consistently higher in late presenters than in early presenters (11.4 vs. 17.2%; p < 0.001). In the IPTW-adjusted dataset, the incidence of all-cause mortality was numerically higher in late presenters than in early presenters (9.1 vs. 12.4%; p = 0.072). In the survival analysis, the cumulative incidence of all-cause mortality was significantly higher in late presenters than in early presenters before and after IPTW. In the subgroup with ST-elevation myocardial infarction, late presenters had a higher incidence of cardiac death than early presenters before (4.8 vs. 10.5%; p < 0.001) and after IPTW (4.2 vs. 9.7%; p = 0.034). In the initial glycated hemoglobin (HbA1c)-stratified analysis, these effects were attenuated in patients with HbA1c ≥ 9.0% before (adjusted hazard ratio [HR]: 1.45, 95% confidence interval [CI]: 0.80-2.64) and after IPTW (adjusted HR: 0.82, 95% CI: 0.40-1.67).

CONCLUSION

Late presentation was associated with higher mortality in patients with AMI-DM; therefore, multifaceted and systematic interventions are needed to decrease pre-hospital delays.

Comparative analyses of the faecal resistome against β-lactam and quinolone antibiotics in humans and livestock using metagenomic sequencing

To assess the prevalence and abundance of antibiotic resistance genes in human and livestock gut microbiomes, 87 humans (healthy individuals and patients with Clostridioides difficile infection (CDI)) and 108 livestock (swine, cattle, and chickens) were enrolled. Gut microbiomes and fluoroquinolone-resistant Escherichia coli isolates were sequenced, and mobile genetic elements adjacent to the β-lactamase (bla) and transferable quinolone resistance (qnr) genes were compared using metagenomic contigs. Each group of humans and livestock exhibited distinctive microbiota and resistome compositions in the gut. Concerning the resistome of bla and qnr, the prevalence rates between chickens and patients with CDI were the most similar (R2 = 0.46); blaTEM, blaOXA, blaCTX-M, and qnrS were highly prevalent in both groups. According to genomic and phylogenetic analyses, blaCTX-M and blaOXA expressed lineage specificity to either humans or livestock, while qnrS and blaTEM displayed a shared lineage between humans and livestock. A qnrS1 mobilome comprising five genes, including two recombinases, a transposase, and a plasmid gene, is commonly found in human and chicken gut microbiomes. Humans and chickens showed the most similar gut resistomes to β-lactams and quinolones. QnrS and blaTEM displayed especially strong co-occurrence between the guts of humans and livestock.

Association between Serum Levels of Interleukin-25/Thymic Stromal Lymphopoietin and the Risk of Exacerbation of Chronic Obstructive Pulmonary Disease

Th2 inflammation is associated with various characteristics of patients with chronic obstructive pulmonary disease (COPD). In this study, we analyzed the COPD exacerbation risk associated with serum levels of interleukin (IL)-25/thymic stromal lymphopoietin (TSLP) and eosinophils. We studied the KOCOSS cohort, a multicenter COPD cohort created by 54 medical centers in South Korea. We extracted data collected between April 2012 and August 2020. We measured serum levels of TSLP and IL-25 in those who agreed to provide blood, and assessed exacerbation risk according to each. In all, 562 patients were enrolled. The IL-25-high group had a lower St. George's Respiratory Questionnaire score than others, and the TSLP-high group had a poorer exercise capacity than the TSLP-low group. There were no significant differences in the forced expiratory volume in 1 s (FEV1), the levels of Th2 inflammatory biomarkers, or the exacerbation histories between the two groups. The 3-year decline in FEV1 was not significantly affected by IL-25 or TSLP levels. In terms of 1-year exacerbation risk, individuals in the IL-25-high group were at lower risk for moderate-to-severe exacerbation than others. A high TSLP level was associated with a lower risk of severe exacerbation but only in the eosinophil-low group. Serum levels of IL-25 are negatively correlated with moderate-to-severe exacerbation risk in this cohort. A negative correlation between severe exacerbation risk and TSLP level was apparent only in the eosinophil-low group.

Prognosis after discontinuing renin angiotensin aldosterone system inhibitor for heart failure with restored ejection fraction after acute myocardial infarction

Prognostic effect of discontinuing renin-angiotensin-aldosterone-system-inhibitor (RAASi) for patients with heart failure (HF) after acute myocardial infarction (AMI) whose left ventricular (LV) systolic function was restored during follow-up is unknown. To investigate the outcome after discontinuing RAASi in post-AMI HF patients with restored LV ejection fraction (EF). Of 13,104 consecutive patients from the nationwide, multicenter, and prospective Korea Acute Myocardial Infarction-National Institutes of Health (KAMIR-NIH) registry, HF patients with baseline LVEF < 50% that was restored to ≥ 50% at 12-month follow-up were selected. Primary outcome was a composite of all-cause death, spontaneous MI, or rehospitalization for HF at 36-month after index procedure. Of 726 post-AMI HF patients with restored LVEF, 544 maintained RAASi (Maintain-RAASi) beyond 12-month, 108 stopped RAASi (Stop-RAASi), and 74 did not use RAASi (RAASi-Not-Used) at baseline and follow-up. Systemic hemodynamics and cardiac workloads were similar among groups at baseline and during follow-up. Stop-RAASi group showed elevated NT-proBNP than Maintain-RAASi group at 36-month. Stop-RAASi group showed significantly higher risk of primary outcome than Maintain-RAASi group (11.4% vs. 5.4%; adjusted hazard ratio [HR_adjust] 2.20, 95% confidence interval [CI] 1.09-4.46, P = 0.028), mainly driven by increased risk of all-cause death. The rate of primary outcome was similar between Stop-RAASi and RAASi-Not-Used group (11.4% vs. 12.1%; HR_adjust 1.18 [0.47-2.99], P = 0.725). In post-AMI HF patients with restored LV systolic function, RAASi discontinuation was associated with significantly increased risk of all-cause death, MI, or rehospitalization for HF. Maintaining RAASi will be necessary for post-AMI HF patients, even after LVEF is restored.

A Case of Multiple Mitochondrial Dysfunctions Syndrome 4 with Novel ISCA2 Variants, Mimicking Post-Infectious Encephalitis

ISCA2 loss of function leads to leukodystrophy and developmental regression (multiple mitochondrial dysfunctions syndrome 4 (MMDS4)). We present a first Korean case of MMDS4 presenting with rapid developmental regression and leukodystrophy after febrile episode, mimicking post-infectious encephalitis. The patient had displayed normal development until 12 months of age. At 13 months of age, one month after experiencing a post-vaccination fever, she quickly progressed to being unable to sit unassisted nor speak any words. Analysis of the cerebrospinal fluid (CSF) revealed lympho-dominant pleocytosis. Amino acid analysis of both the serum and CSF demonstrated elevated glycine exclusively in the CSF. Diffuse leukodystrophy was noted in the brain magnetic resonance image. Whole exome sequencing revealed compound heterozygous ISCA2 variants of c.166T>G, p.C56G and c.422A>C, p.Q141P. No evidence of mitochondrial disease other than bilateral optic atrophy was noted. In cases of early onset rapid developmental regression with leukodystrophy, MMDS4 should be considered.

Urinary incontinence and the association with depression, stress, and self-esteem in older Korean Women

The objectives were to investigate the prevalence of urinary incontinence (UI) and its relationships with depression, stress, and self-esteem in older Korean women from the Korean Study of Women's Health Related Issues (K-Stori), a nationally representative cross-sectional survey. A total of 3000 women between 65 and 79 years were the final study subjects. We applied multiple linear regression models to analyze associations with depression, stress, and self-esteem levels in relation to UI types. Types of urinary incontinence included stress, urge, and mixed UI. UI affects at least one in two older Korean women (52.2%). The prevalences of SUI, UUI, and MUI were 45.7%, 39.6%, and 33.1%, respectively. UI was found to be adversely associated with depression, stress, and self-esteem: women with UI reported significantly higher levels of depression and stress and lower levels of self-esteem than those without UI. Women with MUI reported significantly greater impairment than the women with SUI or UUI. Our results provide an evidence base for the evaluation of mental health in older women with incontinence. The prioritization of UI detection and the identification of psychological factors may help improve the diagnosis and management of UI and potentially yield significant economic and psychosocial benefits.

The Functional Roles and Applications of Immunoglobulins in Neurodegenerative Disease

Natural autoantibodies, immunoglobulins (Igs) that target self-proteins, are common in the plasma of healthy individuals; some of the autoantibodies play pathogenic roles in systemic or tissue-specific autoimmune diseases, such as rheumatoid arthritis and systemic lupus erythematosus. Recently, the field of autoantibody-associated diseases has expanded to encompass neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD), with related studies examining the functions of Igs in the central nervous system (CNS). Recent evidence suggests that Igs have various effects in the CNS; these effects are associated with the prevention of neurodegeneration, as well as induction. Here, we summarize the functional roles of Igs with respect to neurodegenerative disease (AD and PD), focusing on the target antigens and effector cell types. In addition, we review the current knowledge about the roles of these antibodies as diagnostic markers and immunotherapies.

Risk factors that affect the degree of bronchopulmonary dysplasia: Comparison by severity in the same gestational age

Objective

To investigate the risk factors for BPD severity by gestational age (GA) and identify a way to reduce the incidence of moderate-to-severe BPD

Study design

This was a retrospective cohort study of very-low-birth-weight-infants (VLBWIs) delivered at 24 to 28 weeks GA from Korean Neonatal Network registry between 2013 and 2016. BPD was defined using the National Institutes of Health criteria. Study populations were divided by GA and subdivided into no/mild BPD and moderate/severe BPD. The initial statuses of all infants, including those who died before BPD diagnosis and the maternal and neonatal factors of the live infants were compared. Statistical methods included descriptive statistics, comparative tests, and logistic regression.

Results

Of 3,976 infants, 3,717 were included (24weeks, n = 456; 25 weeks, n = 650, 26 weeks, n = 742; 27 weeks, n = 836; 28 weeks, n = 1,033). The overall mortality rate was 18% and the rates by GA were 43%, 29%, 11%, and 6% in the 24-, 25-, 26-, 27-, 28-GA groups, respectively. Small for GA (SGA), treated patent ductus arteriosus (PDA), hypotension, and late-onset sepsis were significant risk factors for developing moderate/severe BPD in the 25 to 28-week GA groups in the multivariate analyses. However, for infants born at 24 weeks GA, there were no significant risk factors apart from initial resuscitation.

Conclusions

Effective initial resuscitation was the most important factor for infants delivered at 24 weeks GA determining the severity of BPD. For infants delivered between 25 and 28 weeks, judicious care of SGA infants, aggressive treatment for PDA and hypotension, and intense efforts to decrease the sepsis rate are needed to reduce the development of moderate-to-severe BPD.

Guideline-directed medical therapy in elderly patients with heart failure with reduced ejection fraction: a cohort study

OBJECTIVES AND DESIGN

Guideline-directed medical therapy (GDMT) with renin-angiotensin system (RAS) inhibitors and beta-blockers has improved survival in patients with heart failure with reduced ejection fraction (HFrEF). As clinical trials usually do not include very old patients, it is unknown whether the results from clinical trials are applicable to elderly patients with HF. This study was performed to investigate the clinical characteristics and treatment strategies for elderly patients with HFrEF in a large prospective cohort.

SETTING

The Korean Acute Heart Failure (KorAHF) registry consecutively enrolled 5625 patients hospitalised for acute HF from 10 tertiary university hospitals in Korea.

PARTICIPANTS

In this study, 2045 patients with HFrEF who were aged 65 years or older were included from the KorAHF registry.

PRIMARY OUTCOME MEASUREMENT

All-cause mortality data were obtained from medical records, national insurance data or national death records.

RESULTS

Both beta-blockers and RAS inhibitors were used in 892 (43.8%) patients (GDMT group), beta-blockers only in 228 (11.1%) patients, RAS inhibitors only in 642 (31.5%) patients and neither beta-blockers nor RAS inhibitors in 283 (13.6%) patients (no GDMT group). With increasing age, the GDMT rate decreased, which was mainly attributed to the decreased prescription of beta-blockers. In multivariate analysis, GDMT was associated with a 53% reduced risk of all-cause mortality (HR 0.47, 95% CI 0.39 to 0.57) compared with no GDMT. Use of beta-blockers only (HR 0.57, 95% CI 0.45 to 0.73) and RAS inhibitors only (HR 0.58, 95% CI 0.48 to 0.71) was also associated with reduced risk. In a subgroup of very elderly patients (aged ≥80 years), the GDMT group had the lowest mortality.

CONCLUSIONS

GDMT was associated with reduced 3-year all-cause mortality in elderly and very elderly HFrEF patients.

TRIAL REGISTRATION NUMBER

NCT01389843.

Clinical Characteristics of Chronic Obstructive Pulmonary Disease in Female Patients: Findings from a KOCOSS Cohort

PURPOSE

The prevalence of chronic obstructive pulmonary disease (COPD) in females has increased, changing the concept of COPD as a disease mostly limited to males. In this study, the clinical characteristics of COPD in females were investigated.

PATIENTS AND METHODS

The study was based on a multicenter cohort of COPD patients recruited from 54 medical centers in South Korea. Sex-based differences in general characteristics, exposure risk factors, depression scores, results of pulmonary function tests, COPD exacerbation, symptom scores, and radiologic findings were evaluated. Sex-related differences in the annual FEV₁ change over 5 years were analyzed in a linear mixed model.

RESULTS

Of the 2515 patients enrolled in this study, 8.1% were female. Female patients who had a higher BMI and a lower level of education were less likely to be smokers, were more exposed to passive smoking/biomass, and were more depressed compared to males. The rates of bronchiectasis, previous childhood respiratory infection, and asthma were higher in females. Female patients also had more symptoms and a poorer exercise capacity than males, but no significant differences were observed in terms of exacerbations. Radiologic findings revealed that male patients had worse emphysema, and female patients had worse bronchiectasis, as determined based on chest X-ray and computed tomography findings. On pulmonary function tests, female patients had less obstruction and less annual FEV₁ loss over 5 years.

CONCLUSION

This study revealed differences in the clinical parameters between male and female patients with COPD, including general characteristics, disease characteristics, and clinical outcomes.

Association between vitamin D deficiency and health-related quality of life in patients with chronic kidney disease from the KNOW-CKD study

Vitamin D deficiency is a growing health problem in both the general population and in patients with chronic kidney disease (CKD). However, the relationship between serum 25-hydroxyvitamin D levels and health-related quality of life in CKD is not well established. This study examined the association between vitamin D deficiency and quality of life in pre-dialysis CKD patients. Serum 25-hydroxyvitamin D levels and the Korean version of the Kidney Disease Quality of Life short form were obtained for 1844 pre-dialysis CKD patients in the prospective KoreaN cohort Study for Outcomes in patients With Chronic Kidney Disease (KNOW-CKD). The baseline estimated glomerular filtration rate was 50.26 ± 0.71 mL/min/1.73 m2. We identified 1294 (70.2%) patients with vitamin D deficiency, defined as a 25-hydroxyvitamin D level < 20 ng/ml. The scores of the kidney disease component summary, physical component summary, and mental component summary in the vitamin D deficiency group were significantly lower compared to the scores of those without vitamin D deficiency. The serum 25-hydroxyvitamin D level was independently associated with the kidney disease component summary and mental component summary scores (β = 0.147, p = 0.003 and β = 0.151, p = 0.047). In conclusion, there was a significant association between serum 25-hydroxyvitamin D levels and kidney disease component summary and mental component summary scores in pre-dialysis CKD patients.

Association of Serum Osteoprotegerin Levels with Bone Loss in Chronic Kidney Disease: Insights from the KNOW-CKD Study

Osteoprotegerin, a potent osteoclast activation inhibitor, decreases bone resorption and positively affects bone mineral density. This study examined the association between serum osteoprotegerin levels and bone loss in patients with chronic kidney disease, a condition associated with increased risk of mineral and bone disorders. The bone mineral densities of the lumbar spine, total hip, and femur neck were assessed by dual-energy X-ray absorptiometry; serum osteoprotegerin levels were measured at baseline for 1,423 patients enrolled in the prospective KoreaN cohort study for Outcome in patients With Chronic Kidney Disease (KNOW-CKD). Patients aged ≥50 years and with a T-score ≤ -2.5 were diagnosed as having osteoporosis. Multivariable linear regression analysis indicated independent association between serum osteoprotegerin levels and decreased bone mineral density in the lumbar spine (B: -0.489, 95% confidence interval [CI]: -0.883 to -0.095, P = 0.015), and total hip (B: -0.349, 95% CI: -0.672 to -0.027, P = 0.027). However, bone mineral density of the femur neck was not associated with serum osteoprotegerin levels in women. After adjustments, no independent association was found between serum osteoprotegerin levels and bone mineral density in men. In multivariable logistic regression analysis, serum osteoprotegerin levels were associated with increased risk of osteoporosis in women (odds ratio [OR]: 4.72, 95% CI: 1.35 to 16.52, P = 0.015), but not in men (OR: 0.21; 95% CI: 0.04 to 1.31, P = 0.095). To summarize, in female patients with chronic kidney disease, increased serum osteoprotegerin levels were independently associated with decreased bone mineral density in the lumbar spine and total hip, and with increased risk of osteoporosis. Therefore, the measurement of serum osteoprotegerin concentration might be useful as a surrogate marker for determining bone loss in patients with chronic kidney disease, especially for women, although not so much for men.