Trends in body mass index changes among Korean adolescents between 2005-2020, including the COVID-19 pandemic period: a national representative survey of one million adolescents

OBJECTIVE

The impact of the coronavirus disease 2019 (COVID-19) pandemic on weight gain in children and adolescents remains unknown. We aimed to identify an estimated 15-year trend in mean body mass index (BMI) changes and prevalence of obesity and overweight among Korean adolescents from 2005 to 2020, including the period of the COVID-19 pandemic.

PATIENTS AND METHODS

We analyzed data taken from a nationwide survey (Korea Youth Risk Behavior Survey), between 2005 and 2020. Representative samples of one million Korean adolescents aged 13-18 years (n=1,057,885) were examined. The 15-year trends in mean BMI and proportion of obesity or overweight, and the changes due to the COVID-19 pandemic were analyzed.

RESULTS

The data of 1,057,885 Korean adolescents were analyzed (mean age: 14.98 years; females, 48.4%). The estimated weighted mean BMI was 20.5 kg/m2 [95% confidence interval (CI), 20.4-20.5] from 2005 to 2008 and 21.5 kg/m2 (95% CI, 21.4-21.6) in 2020 (during the COVID-19 pandemic). Although the 15-year trend of mean BMI gradually increased, the change in mean BMI before and during the pandemic significantly lessened (βdiff, -0.027; 95% CI, -0.028 to -0.026). The 15-year (2005-2020) trend changes in the prevalence of obesity and overweight were similar (obesity prevalence from 2005-2008, 3.2%; 95% CI, 3.1-3.3 vs. obesity prevalence in 2020, 8.6%; 95% CI, 8.2-9.0; βdiff, -0.309; 95% CI, -0.330 to -0.288).

CONCLUSIONS

The 15-year trend of overall mean BMI and obesity and overweight prevalence demonstrated a significant increase; however, its slope decreased during the pandemic. These landmark results suggest the need for the development of precise strategies to prevent pediatric obesity and overweight during the COVID-19 pandemic.

Increased Risk of Cancer after Cholecystectomy: A Nationwide Cohort Study in Korea including 123,295 Patients

Background/Aims

Contradictory findings on the association between cholecystectomy and cancer have been reported. We aimed to investigate the risk of all types of cancers or site-specific cancers in patients who underwent cholecystectomy using a nationwide dataset.

Methods

Subjects who underwent cholecystectomy from January 1, 2007, to December 31, 2014, who were older than 20 years and who underwent an initial baseline health check-up within 2 years were enrolled. Those who were diagnosed with any type of cancer before the enrollment or within 1 year after enrollment were excluded. Ultimately, patients (n=123,295) who underwent cholecystectomy and age/sex matched population (n=123,295) were identified from the database of the Korean National Health Insurance Service. The hazard ratio (HR) and 95% confidence interval (CI) for cancer were estimated, and Cox regression analysis was performed.

Results

The incidence of cancer in the cholecystectomy group was 9.56 per 1,000 personyears and that in the control group was 7.95 per 1,000 person-years. Patients who underwent cholecystectomy showed an increased risk of total cancer (adjusted HR, 1.19; 95% CI, 1.15 to 1.24; p<0.001), particularly leukemia and malignancies of the colon, liver, pancreas, biliary tract, thyroid, pharynx, and oral cavity. In the subgroup analysis according to sex, the risk of developing cancers in the pancreas, biliary tract, thyroid, lungs and stomach was higher in men than in women.

Conclusions

Physicians should pay more attention to the possibility of the occurrence of secondary cancers among patients who undergo cholecystectomy.

Aberrant DNA Methylation Maker for Predicting Metachronous Recurrence After Endoscopic Resection of Gastric Neoplasms

Purpose

To investigate whether MOS methylation can be useful for the prediction of metachronous recurrence after endoscopic resection of gastric neoplasms.

Materials and Methods

From 2012 to 2017, 294 patients were prospectively enrolled after endoscopic resection of gastric dysplasia (n=171) or early gastric cancer (n=123). When H. pylori was positive, eradication therapy was performed. Among them, 124 patients completed the study protocol (follow-up duration > 3 years or development of metachronous recurrence during the follow-up.) Methylation levels of MOS were measured at baseline using quantitative MethyLight assay from the antrum.

Results

Median follow-up duration was 49.9 months. MOS methylation levels at baseline were not different by age, sex, and current H. pylori infection, but they showed a weak correlation with operative link on gastritis assessment (OLGA) or operative link on gastric intestinal metaplasia assessment (OLGIM) stages (Spearman's ρ = 0.240 and 0.174, respectively, p < 0.05). During the follow-up, a total of 20 metachronous gastric neoplasms (13 adenomas and 7 adenocarcinomas) were developed. Either OLGA or OLGIM stage was not useful in predicting the risk for metachronous recurrence. In contrast, MOS methylation high group (≥ 34.82 %) had a significantly increased risk for metachronous recurrence compared to MOS methylation low group (adjusted hazard ratio [95% confidence interval]. 4.76 [1.54,14.79], p=0.007).

Conclusion

MOS methylation can be a promising marker for predicting metachronous recurrence after endoscopic resection of gastric neoplasms. To confirm the usefulness of MOS methylation, validation studies are warranted in the future. (ClinicalTrials No.: NCT04830618).

Nationwide cohort study: cholesterol level is inversely related with the risk of gastric cancer among postmenopausal women

BACKGROUND

Recent studies showed inverse relationship between hypercholesterolemia and the risk of gastric cancer, especially among male. However evidence among female is inconsistent. We aimed to investigate the relationship between cholesterol level and the risk of gastric cancer among female according to menopausal status.

METHODS

We analyzed the data from a population-based prospective cohort of female ≥ 30 years old who underwent cancer screening and general health screening provided by the Korean National Health Insurance Corporation in 2009. Under quartile stratification of the level of cholesterol components, we calculated the hazard ratio (HR) for gastric cancer incidence until 2018 for each level group according to the menopausal status at 2009.

RESULTS

Among total 2,722,614 individuals, 17,649 gastric cancer cases developed after mean 8.26 years of follow-up (premenopausal 3746/1180666; postmenopausal 13,903/1541948). Total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) showed inverse relationship with the risk of gastric cancer among postmenopausal women (adjusted HR (95% confidence interval) for the highest quartile vs. lowest quartile and p-for-trend: 0.88 (0.84-0.92) and < 0.001 for total cholesterol; 0.89 (0.85-0.92) and < 0.001 for HDL-C; 0.92 (0.89-0.97) and 0.001 for LDL-C), whereas none showed statistically significant risk relationship among premenopausal women. Triglyceride was not independently related with gastric cancer risk among both pre- and postmenopausal women.

CONCLUSIONS

Cholesterol levels, including total cholesterol, HDL-C, and LDL-C, are inversely related with the risk of gastric cancer among postmenopausal women, but not among premenopausal women.

2020 Seoul Consensus on the Diagnosis and Management of Gastroesophageal Reflux Disease

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the “proven GERD” with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett’s mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis.

Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Association between obesity and the risk of gastric cancer in premenopausal and postmenopausal women: A nationwide cohort study

BACKGROUND AND AIM

Obesity was suggested to increase the incidence of gastric cancer (GC) in women, but results from previous studies were inconsistent. We investigated the relationship between obesity and the risk of GC according to menopausal status.

METHODS

We enrolled 1 418 180 premenopausal and 4 854 187 postmenopausal women aged ≥ 40 years using the Korean National Health Insurance System Cohort (2009-2014). We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) for GC incidence according to body mass index (BMI) and waist circumference (WC) using the Cox proportional hazards models.

RESULTS

During the mean follow-up period of 7.2 years, 42 441 women were newly diagnosed with GC. Compared with the group with BMI 18.5-22.9 kg/m² , the adjusted HRs (95% CIs) for GC in the groups with BMI < 18.5, 23-24.9, 25-29.9, and ≥ 30 kg/m² were 1.12 (0.95-1.33), 0.96 (0.89-1.04), 1.02 (0.94-1.11), and 0.99 (0.83-1.18), respectively, for premenopausal women and 1.07 (1.00-1.14), 1.01 (0.99-1.04), 1.03 (1.00-1.05), and 1.11 (1.10-1.16), respectively, for postmenopausal women. Compared with the group with WC 65-74.9 cm, the adjusted HRs (95% CIs) for GC for the groups with WC < 65, 75-84.9, 85-94.9, and ≥ 90 cm were 1.00 (0.88-1.15), 1.03 (0.96-1.11), 1.10 (0.99-1.22), and 1.02 (0.81-1.27), respectively, for premenopausal women and 1.01 (0.94-1.09), 1.01 (0.99-1.04), 1.09 (1.06-1.13), and 1.14 (1.09-1.19), respectively, for postmenopausal women.

CONCLUSIONS

We found a positive association between the highest BMI and WC category and risk of GC in postmenopausal women; however, such an association was not evident in premenopausal women.

Temporal change in the diagnosis and treatment rates of osteoporosis: results from the Korea National Health and Nutrition Examination Survey

To compare the diagnosis andtreatment rates of osteoporosis and diabetes in Korea, a nationwide database was used. The results showed that although osteoporosis management is improving, it is still lower compared with that of diabetes; thus, further efforts are needed in this regard.

INTRODUCTION

This study aimed to re-evaluate the diagnosis and treatment of osteoporosis from the KNHANES 2016-2017 and compare the temporal change of the rate with those of diabetes as another prevalent chronic disease in South Korea.

METHODS

The prevalence of osteoporosis in 2016 was estimated using the previous data classified by age groups (50-59,60-69, and ≥70years) and the 2016 Korean census data. The physician diagnosis and treatment rates of osteoporosis in adults aged ≥50years were estimated using the 2016-2017 KNHANES data. The physician diagnosis and treatment rates of diabetes were evaluated using the KNHANES 2008-2009 and 2016-2017 data.

RESULTS

The estimated physician diagnosisrate of osteoporosis increased from 29.9% in females and 5.8% in males in 2008-2009 to 62.8% in females and 22.8% in males in 2016-2017. The treatment rate for the estimated total number of patients with osteoporosis increased from 14.4% in females and 3.8% in males in 2008-2009 to 32.2% in females and 9.0% in males in 2016-2017. An increasing trend in the estimated treatment rateof physician-diagnosed osteoporosis patients was not observed (48.3% [2008-2009] vs 51.5% [2016-2017] in females; 42.6% [2008-2009] vs 42.2% [2016-2017] in males). The physician diagnosis and treatment rates of diabetes were considerably better and more stable than those of osteoporosis.

CONCLUSION

Osteoporosis management in South Korea is improving but is insufficient compared with diabetes management. More extensive efforts are needed to improve the diagnosis and treatment rates of osteoporosis.

The beneficial effects of menopausal hormone therapy on renal survival in postmenopausal Korean women from a nationwide health survey

Several studies have demonstrated the nephroprotective effects of estrogen on renal damage. In light of the inconsistent results of previous findings, this study aims to evaluate the in-depth role of menopausal hormone therapy (MHT) on the development of end stage renal disease (ESRD). 3,109,506 Korean adult women who had undergone a medical examination in 2009 (index year) were initially identified for inclusion in this study. We excluded subjects had not experienced menopause naturally, had data missing for at least one variable, and were diagnosed with ESRD within 1 year from the index year. MHT data was obtained from self-reporting questionnaires and the primary outcome was the development of ESRD from the index year until December 31, 2018. A final total of 1,460,311 subjects were included in this study. The participants were divided into four groups according to the duration of MHT; no history of MHT, MHT < 2 years, 2 ≤ MHT < 5 years, MHT ≥ 5 years. During the 9-year study period, a total of 4905 participants developed ESRD. The participants who had a history of MHT use were found to have a 30% reduced risk of developing ESRD. Results from the subgroup analyses were similar to that of the primary study. The findings in this study demonstrate the beneficial effects of MHT on the development of ESRD in postmenopausal women. Based on results, our study may offer suggestions for further studies to investigate the therapeutic options on kidney disease.

Resolvin D1 suppresses inflammation-associated tumorigenesis in the colon by inhibiting IL-6-induced mitotic spindle abnormality

While failure in resolution of inflammation is considered to increase the risk of tumorigenesis, there is paucity of experimental as well as clinical evidence supporting this association. Resolvin D1 (RvD1) is a representative pro-resolving lipid mediator that is endogenously generated from docosahexaenoic acid for the resolution of inflammation. Here, we report a decreased level of RvD1 in the blood from colorectal cancer patients and mice having inflammation-induced colon cancer, suggesting plasma RvD1 as a potential biomarker for monitoring colorectal cancer. Administration of RvD1 attenuated dextran sodium sulfate (DSS)-induced colitis and azoxymethane (AOM) plus DSS-induced colorectal carcinogenesis by suppressing the production of interleukin-6 (IL-6) and IL-6-mediated chromosomal instability. The protective effect of RvD1 against chromosomal instability is associated with downregulation of IL-6-induced Cyclin D1 expression, which appears to be mediated by blocking the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) axis. RvD1 inhibited the STAT3 signaling pathway by interfering with the binding of IL-6 to its receptor (IL-6R), suggesting the novel function of RvD1 as a putative IL-6R antagonist. Together, our findings suggest that RvD1-mediated blockade of IL-6 signal transmission may contribute to inhibition of chromosomal instability and tumorigenesis.

In-depth characterization of non-human sialic acid (Neu5Gc) in human serum using label-free ZIC-HILIC/MRM-MS

Sialic acid Neu5Gc, a non-human glycan, is recognized as a new harmful substance that can cause vascular disease and cancer. Humans are unable to synthesize Neu5Gc due to a genetic defect that converts Neu5Ac to Neu5Gc, but Neu5Gc is often observed in human biological samples. Therefore, the demand for accurately measuring the amount of Neu5Gc present in human blood or tissues is rapidly increasing, but there is still no method to reliably quantify trace amounts of a non-human sugar. In particular, selective isolation and detection of Neu5Gc from human serum is analytically challenging due to the presence of excess sialic acid Neu5Ac, which has physicochemical properties very similar to Neu5Gc. Herein, we developed the label-free approach based on ZIC-HILIC/MRM-MS that can enrich sialic acids released from human serum and simultaneously monitor Neu5Ac and Neu5Gc. The combination of complete separation of Neu5Gc from abundant Neu5Ac by hydrophilic and electrostatic interactions with selective monitoring of structure-specific cross-ring cleavage ions generated by negative CID-MS/MS was remarkably effective for quantification of Neu5Ac and Neu5Gc at the femtomole level. Indeed, we were able to successfully determine the absolute quantitation of Neu5Gc from 30 healthy donors in the range of 3.336 ± 1.252 pg/μL (mean ± SD), 10,000 times lower than Neu5Ac. In particular, analysis of sialic acids in protein-free serum revealed that both Neu5Ac and Neu5G are mostly bound to proteins and/or lipids, but not in free form. In addition, the correlation between expression level of Neu5Gc and biological factors such as BMI, age, and sex was investigated. This method can be widely used in studies requiring sialic acid-related measurements such as disease diagnosis or prediction of immunogenicity in biopharmaceuticals as it is both fast and highly sensitive.

Association Between the Persistence of Obesity and the Risk of Gastric Cancer: A Nationwide Population-Based Study

Purpose

There remains controversy about relationship between obesity and gastric cancer. We aimed to examine the association using obesity-persistence.

Materials and Methods

We analyzed a nationwide population-based cohort which underwent health check-up between 2009 and 2012. Among them those who had annual examinations during the last 5 years were selected. Gastric cancer risk was compared between those without obesity during the five years (never-obesity group) and those with obesity diagnosis during the five years (non-persistent obesity group; persistent obesity group).

Results

Among 2,757,017 individuals, 13,441 developed gastric cancer after median 6.78 years of follow-up. Gastric cancer risk was the highest in persistent obesity group (incidence rate (IR), 0.89/1,000 person-years; hazard ratio (HR), 1.197; 95% confidence interval (CI), 1.117-1.284), followed by non-persistent obesity group (IR, 0.83/1,000 person-years; HR, 1.113; 95% CI, 1.056-1.172) compared with never-obesity group. In subgroup analysis, this positive relationship was true among those <65 years old and male. Among heavy-drinkers, the impact of obesity-persistence on the gastric cancer risk far increased (non-persistent obesity: HR 1.297, 95% CI 1.094-1.538; persistent obesity: HR 1.351, 95% CI 1.076-1.698).

Conclusion

Obesity-persistence is associated with increased risk of gastric cancer in a dose-response manner, especially among male <65 years old. The risk raising effect was much stronger among heavy-drinkers.

Gastrectomy, vitamin B12 supplementation and the risk of Parkinson's disease: A nationwide cohort study

INTRODUCTION

Previous evidence has suggested roles for α-synuclein propagation and vitamin B12 (VitB12) deficiency in the pathogenesis of Parkinson's disease (PD). We investigated whether gastric cancer (GC) patients who underwent gastrectomy had a lower risk of PD and whether VitB12 supplementation modified the risk.

METHODS

GC patients aged ≥50 years who underwent curative gastrectomy between 2007 and 2012 (n = 72,216) and matched comparison groups (n = 211,389) were identified from the Korean National Health Insurance database. The risks of PD were analyzed by Cox regression.

RESULTS

Compared to their matched comparison groups, GC patients who underwent gastrectomy showed a decreased risk of PD (adjusted HR [aHR] 0.86; 95% confidence interval [CI] 0.75-0.98), but the significance disappeared after further adjustment with smoking and body mass index (BMI). To elaborate, subtotal gastrectomy (STG) was associated with decreased risk of PD (aHR 0.85; 95% CI 0.74-0.99) while total gastrectomy (TG) was not (aHR 0.89; 95% CI 0.66-1.19), although the risk reduction was not significant when further adjusted for smoking and BMI. Among the patients who underwent TG, their risk of PD was markedly lower when they had VitB12 supplementation after surgery (aHR 0.36; 95% CI 0.17-0.76), while the risk was higher when they did not have any (aHR 1.55; 95% CI 1.03-2.32).

CONCLUSIONS

GC patients who underwent gastrectomy and received uninterrupted VitB12 supplementation had a decreased incidence of PD. This study provides indirect epidemiological evidence for the potential roles of gastrectomy and VitB12 in the pathogenesis of PD.

Association between high fatty liver index and development of colorectal cancer: a nationwide cohort study with 21,592,374 Korean

BACKGROUND/AIMS

In Korea, the incidence of colorectal cancer (CRC) and nonalcoholic fatty liver disease (NAFLD) has increased due to a westernized lifestyle. This study investigated whether a high fatty liver index that reflects NAFLD correlates with CRC.

METHODS

Data from the National Health Insurance Corporation 2009 to 2012 were analyzed. NAFLD disease was defined as a fatty liver index > 60 in the absence of alcohol consumption of ≥ 30 g/day.

RESULTS

NAFLD was identified in 2,543,649 (11.8%) of 21,592,374 participants. CRC was identified in 19,785 (0.8%) of participants with NAFLD (fatty liver index ≥ 60) and in 80,871 (0.6%) participants without NAFLD (fatty liver index < 30). Multivariate logistic regression analysis demonstrated an independent association between NAFLD and CRC after adjusting for other confounders (hazard ratio, 1.13; odds ratio, 1.12 to 1.15). In subgroup analyses, fatty liver index ≥ 60 was associated with CRC regardless of body mass index, but the association was more prominent in persons with a normal index. NAFLD, in the absence of diabetes, hypertension, or dyslipidemia, was more highly associated with CRC than when one or more of these conditions are present.

CONCLUSION

CRC should be considered as a possibility in patients with fatty liver index ≥ 60, even in the absence of obesity or other metabolic syndromes.

Treatment of non-erosive reflux disease and dynamics of the esophageal microbiome: a prospective multicenter study

Non-erosive reflux disease (NERD) pathogenesis has not been thoroughly evaluated. Here, we assessed the response of patients with NERD to proton pump inhibitor (PPI) therapy; changes in the microbiome and biologic marker expression in the esophageal mucosa were also evaluated. Patients with NERD (n = 55) received esomeprazole (20 mg) for eight weeks. The treatment response was evaluated at baseline, week four, and week eight. Esophageal mucosal markers and oropharyngeal and esophageal microbiomes were analyzed in patients who underwent upper gastrointestinal endoscopy at screening (n = 18). Complete and partial response rates at week eight were 60.0% and 32.7% for heartburn, and 61.8% and 29.1% for regurgitation, respectively. The expressions of several inflammatory cytokines, including IL-6, IL-8, and NF-κB, were decreased at week eight. Streptococcus, Haemophilus, Prevotella, Veillonella, Neisseria, and Granulicatella were prevalent regardless of the time-point (baseline vs. week eight) and organ (oropharynx vs. esophagus). The overall composition of oropharyngeal and esophageal microbiomes showed significant difference (P = 0.004), which disappeared after PPI therapy. In conclusion, half-dose PPI therapy for eight weeks could effectively control NERD symptoms. The expression of several inflammatory cytokines was reduced in the esophagus, and oropharyngeal and esophageal microbiomes in patients with NERD showed significant difference. However, the microbial compositions in the oropharynx and esophagus were not affected by PPI therapy in this study. Impact of PPI on the microbiome in patients with NERD should be more investigated in future studies.

Thin-Section MR Imaging for Carotid Cavernous Fistula

BACKGROUND AND PURPOSE

Carotid-cavernous fistulas are abnormal vascular shunts that can cause various neurologic or orbital symptoms. The purpose of this retrospective study was to evaluate the diagnostic performance of thin-section MR imaging for carotid cavernous fistula in patients with clinically suspected carotid cavernous fistula, and to identify possible imaging predictors of carotid cavernous fistula.

MATERIALS AND METHODS

A total of 98 patients who were clinically suspected of having carotid cavernous fistula (according to their symptoms and physical examinations) between January 2006 and September 2018 were included in this study. The patients underwent pretreatment thin-section MR imaging and DSA. Thin-section MR imaging consisted of 2D coronal T1- and T2WI with 3-mm thickness and 3D contrast-enhanced T1WI with 0.6 mm thickness. The diagnostic performance of thin-section MR imaging for carotid cavernous fistula was evaluated with the reference standard of DSA. Univariate logistic regression analysis was performed to determine possible imaging predictors of carotid cavernous fistula.

RESULTS

Among the 98 patients, DSA confirmed 38 as having carotid cavernous fistula. The overall accuracy, sensitivity, and specificity of thin-section MR imaging were 88.8%, 97.4%, and 83.3%, respectively. Possible imaging predictors on thin-section MR imaging included abnormal contour of the cavernous sinus (OR: 21.7), internal signal void of the cavernous sinus (OR: 15.3), prominent venous drainage flow (OR: 54.0), and orbital/periorbital soft tissue swelling (OR: 40.4).

CONCLUSIONS

Thin-section MR imaging provides high diagnostic performance and possible imaging predictors of carotid cavernous fistula in patients with clinically suspected carotid cavernous fistula. Thin-section MR imaging protocols could help decide appropriate management plans for patients with clinically suspected carotid cavernous fistula.

Diagnostic Accuracy of MRI-Based Morphometric Parameters for Detecting Olfactory Nerve Dysfunction

BACKGROUND AND PURPOSE

Although olfactory dysfunction is a common cranial nerve disorder, there are no simple objective morphometric criteria to assess olfactory dysfunction. The aim of this study was to evaluate the diagnostic performance of MR imaging morphometric parameters for detecting olfactory dysfunction.

MATERIALS AND METHODS

This prospective study enrolled patients from those presenting with olfactory symptoms who underwent both an olfactory function test and MR imaging. Controls without olfactory dysfunction were recruited during the preoperative work-up for pituitary adenoma. Two independent neuroradiologists measured the olfactory bulb in 3D and assessed olfactory bulb concavity on MR imaging while blinded to the clinical data. Diagnostic performance was assessed using receiver operating characteristic curve analysis.

RESULTS

Sixty-four patients and 34 controls were enrolled. The patients were significantly older than the controls (mean age, 57.8 ± 11.9 years versus 47.1 ± 12.1 years; P < .001). Before age adjustment, the olfactory bulb height was the only olfactory bulb parameter showing a significant difference between patients and controls (1.6 ± 0.3 mm versus 2.0 ± 0.3 mm, P < .001). After age adjustment, all parameters and olfactory bulb concavity showed significant intergroup differences, with the olfactory bulb height having the highest area under the curve (0.85). Olfactory bulb height was confirmed to be the only significant parameter showing a difference in the detection of olfactory dysfunction in 22 pairs after matching for age and sex (area under the curve = 0.87, P < .001). Intraclass correlation coefficients revealed moderate-to-excellent degrees of inter- and intrareader agreement.

CONCLUSIONS

MR imaging morphometric analysis can differentiate patients with olfactory dysfunction, with the olfactory bulb height having the highest diagnostic performance for detecting olfactory dysfunction irrespective of age.

Family-based exome sequencing combined with linkage analyses identifies rare susceptibility variants of MUC4 for gastric cancer

Genome-wide association studies of gastric cancer (GC) cases have revealed common gastric cancer susceptibility loci with low effect size. We investigated rare variants with high effect size via whole-exome sequencing (WES) of subjects with familial clustering of gastric cancer. WES of DNAs from the blood of 19 gastric cancer patients and 36 unaffected family members from 14 families with two or more gastric cancer patients were tested. Linkage analysis combined with association tests were performed using Pedigree Variant Annotation, Analysis, and Search Tool (pVAAST) software. Based on the logarithm of odds (LOD) and permutation-based composite likelihood ratio test (CLRT) from pVAAST, MUC4 was identified as a predisposing gene (LOD P-value = 1.9×10-5; permutation-based P-value of CLRT ≤ 9.9×10-9). In a larger cohort consisting of 597 GC patients and 9,759 healthy controls genotyped with SNP array, we discovered common variants in MUC4 regions (rs148735556, rs11717039, and rs547775645) significantly associated with GC supporting the association of MUC4 with gastric cancer. And the MUC4 variants were found in higher frequency in The Cancer Genome Atlas Study (TCGA) germline samples of patients with multiple cancer types. Immunohistochemistry indicated that MUC4 was downregulated in the noncancerous gastric mucosa of subjects with MUC4 germline missense variants, suggesting that loss of the protective function of MUC4 predisposes an individual to gastric cancer. Rare variants in MUC4 can be novel gastric cancer susceptibility loci in Koreans possessing the familial clustering of gastric cancer.

Expression of Tight Junction Proteins According to Functional Dyspepsia Subtype and Sex

Background/Aims

To determine whether the expression of tight junction proteins (TJPs) differs depending on the subtype of functional dyspepsia (FD) and sex.

Methods

Control (n = 95) and FD (n = 165) groups based on Rome III criteria were prospectively enrolled. Gastric mucosal mRNA expression levels of various TJPs (claudins [CLDN] 1, 2, and 4; zonula occludens-1; occludin [OCLN]) were assessed by reverse transcription polymerase chain reaction. Western blot was performed to determine the levels of various TJPs. Helicobacter pylori infection status was evaluated by histology, rapid urease test, and culture. Questionnaires were analyzed.

Results

In all groups irrespective of H. pylori, FD group showed significantly higher CLDN2 mRNA levels than control group (P = 0.048). The level of CLDN4 mRNA expression was significantly lower in female FD group than in male FD group (P = 0.018). In H. pylori uninfected subjects, the level of CLDN1 mRNA expression in female FD group was significantly lower than that of male FD group (P = 0.014). The level of CLDN2 mRNA expression was significantly higher in the male postprandial distress syndrome (P = 0.001) and male epigastric pain syndrome (P = 0.023) groups than in the male control group. In Western blot analysis, the expression of OCLN was significantly elevated 48 hour after the culture with H. pylori strain 43504.

Conclusions

H. pylori can affect a variety of TJPs, particularly claudin-4 and occludin. Claudin-2 is thought to be involved in FD irrespective of H. pylori status, especially in the pathophysiology of male FD.

Dipstick proteinuria and cancer incidence: a nationwide population-based study

BACKGROUND

The association between proteinuria and malignancy has been frequently reported, but the issue is matter of controversy. Thus, in order to shed light on the association, we evaluated proteinuria as a risk factor for malignancy using the dataset from the Korean National Health Insurance System (NHIS).

METHODS

The subjects had undergone a medical examination in 2009 (index year) among the entire Korean adult population. From a pool of 10,505,818 participants, we excluded subjects who were younger than 19 years (15,327), had a previous diagnosis of cancer (152,095), had missing data for at least one variable (544,508), and were diagnosed with cancer within 1 year from the index year (79,501). Proteinuria was examined by a single dipstick urinalysis.

RESULTS

A total of 9,714,387 subjects were included in this study and tracked until December 31, 2017. The participants were divided into three groups; no (95.2%), trace (2.3%), and overt (2.5%) proteinuria. Over the duration of this study, we observed that overt proteinuria was associated with an increased risk of cancer development (all cancers) (adjusted HR 1.154, 95% CI 1.134-1.173) and the long-term risk of cancer incidence increased proportionally according to the changes in proteinuria over a four-year period.

LIMITATIONS

Our study population consisted of Korean adults. Therefore, the results of this study may not be generalized to other ethnicities.

CONCLUSIONS

We found a significant relationship between proteinuria and the risk of overall and site-specific cancer development. Further studies are needed to find an explanation of these findings.

Diagnostic performance of MRI to detect metastatic cervical lymph nodes in patients with thyroid cancer: a systematic review and meta-analysis

AIM

To evaluate the diagnostic performance of magnetic resonance imaging (MRI) in the diagnosis of metastatic cervical lymph nodes.

MATERIALS AND METHODS

Ovid-MEDLINE and EMBASE databases were searched up until 12 June 2018. Eleven articles were included in the qualitative systematic review and nine of the 11 in the quantitative analysis. Two radiologists independently performed data extraction and methodological quality assessment using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A qualitative systematic review and quantitative analysis were performed, followed by a meta-regression analysis to determine factors causing heterogeneity.

RESULTS

The pooled sensitivity and specificity in the diagnosis of metastatic cervical lymph nodes were 80% (95% confidence interval [CI]: 68-88%) and 85% (95% CI: 63-95%), respectively. The sensitivity and false-positive rate (correlation coefficient, 0.655) showed a positive correlation due to a threshold effect, which was responsible for heterogeneity across the studies, as indicated by a Q-test (p<0.01) and Higgins I² statistic (sensitivity, I²=90.11%; specificity, I²=92.49%). In the meta-regression analysis, fat-suppressed imaging, and the analysis method were significant factors influencing the heterogeneity in diagnostic performance.

CONCLUSIONS

MRI shows moderate diagnostic performance in the diagnosis of metastatic lymph nodes in patients with thyroid cancer in the neck. MRI may be an optional or complementary imaging method to ultrasound or computed tomography (CT) in thyroid cancer patients.

Preoperative evaluation of mammographic microcalcifications after neoadjuvant chemotherapy for breast cancer

AIM

To assess the predictive value of preoperative residual mammographic microcalcifications for residual tumours after neoadjuvant chemotherapy (NAC) for breast cancer.

MATERIALS AND METHODS

This single-centre retrospective study included breast cancer patients who underwent NAC and demonstrated suspicious microcalcifications within or near the tumour bed on mammography from June 2015 to August 2018. The residual microcalcifications and remnant lesion on magnetic resonance imaging (MRI) were correlated with histopathological findings of residual tumours and immunohistochemical markers.

RESULTS

A total of 96 patients were included. Ten patients achieved pathological complete response (pCR) and previous suspicious microcalcifications were associated with benign pathology in 10.4% (10/96) of the patients. In the remaining 86 patients who did not achieve pCR, 61.5% (59/96) of the residual microcalcifications were associated with invasive or in situ carcinoma and 28.1% (27/96) with benign pathology. Hormone receptor-positive (HR⁺) patients had the highest proportion of residual malignant microcalcifications compared to HR^- patients (48.9% versus 13.5%, respectively; p=0.019). MRI correlated better than residual microcalcifications on mammography in predicting residual tumour extent in all subtypes (ICC=0.709 versus 0.365). MRI also showed higher correlation with residual tumour size for the HR^-/HER2⁺ and HR^-/HER2^- subtype (ICC=0.925 and 0.876, respectively).

CONCLUSION

The extent of microcalcifications on mammography after NAC did not correlate with the extent of residual cancer in 38.5% of women. Regardless of the extent of microcalcifications, residual tumour extent on MRI after NAC and molecular subtype could be an accurate tool in evaluating residual cancer after NAC.

Treatment pattern and overall survival in esophageal cancer during a 13-year period: A nationwide cohort study of 6,354 Korean patients

Using data from the real world to solve clinical questions that cannot be answered using data from clinical trials is attracting more attention. Clinical outcomes for patients with esophageal cancer in a real-world setting might be different from data in randomized controlled trials. This study aimed to provide real world data on treatment and prognosis in Korean patients with esophageal cancer. This retrospective cancer cohort included newly diagnosed cases of esophageal cancer at 19 tertiary hospitals between January 1, 2005 and December 31, 2017. Cancer staging was defined according to the 7th edition of the American Joint Committee on Cancer criteria. We identified 6,354 patients with newly diagnosed esophageal cancer (mean age: 64.9 ± 9.0 years, 96.9% squamous cell carcinoma). The proportion of early esophageal cancer increased from 24.7% in 2005 to 37.2% in 2015 (p<0.001). Among all cases, surgery alone was 31.3%, followed by definitive concurrent chemoradiotherapy (CCRT) (27.0%), neoadjuvant therapy (12.4%), adjuvant therapy (11.1%), and endoscopic resection (5.8%). The 5-year overall survival rate was 45.7 ± 0.7%. Endoscopic resection provided similar median survival relative to surgery for stage Ia cases. Among stage II–III cases, definitive CCRT was associated with poorer survival than neoadjuvant or adjuvant therapy, although there was no survival difference between neo-adjuvant and adjuvant therapy. Early esophageal cancer is gradually becoming more common and endoscopic resection provided similar long-term survival relative to surgery. Surgery with combined therapy provided better survival in locally advanced esophageal cancer, relative to definitive CCRT.