Objective: In this study, we aimed to investigate the incidence and risk factors for interstitial nephritis in patients with ankylosing spondylitis (AS). Methods: We retrospectively analyzed the claims records of patients diagnosed with AS in Korea’s Health Insurance Review and Assessment Service Database between 2016 and 2019. The Assessment of Spondyloarthritis International Society nonsteroidal anti-inflammatory drugs (NSAIDs) intake score was used to calculate the NSAID dosage over 1 year after AS diagnosis. The incidence rate of interstitial kidney disease was calculated as the number of events per 1,000 person-years. The risks associated with sex, age, Charlson Comorbidity Index, comorbidities, and concomitant medications were assessed using the Cox proportional hazards model, with results presented as hazard ratios (HRs) and 95% confidence intervals (CIs). Results: In total, 11,749 patients with AS were included in this study. Of these, 79 patients had interstitial nephritis, with an incidence rate of 2.50 per 1,000 person-years. In multivariable analysis, female sex (HR, 2.44; 95% CI, 1.56~3.83), hypertension (HR, 2.08; 95% CI, 1.15~3.76), and renal failure (HR, 3.70; 95% CI, 1.30~10.55) showed significant associations. However, NSAID use in the first year after AS diagnosis was not associated with interstitial nephritis occurrence. Conclusion The incidence of interstitial nephritis in patients with AS was 2.50 per 1,000 person-years, with female sex and comorbidities identified as significant risk factors. However, NSAID use during the first year after AS diagnosis was not associated with interstitial nephritis development.

Objectives: Allergic rhinitis (AR) is a chronic inflammation of the nasal mucosa triggered by environmental allergens. Although its pathophysiology has been extensively investigated, the influence of environmental aggravating factors—particularly combined pollutant exposure—remains insufficiently characterized. This study aimed to assess the impact of coexposure to PM2.5, formaldehyde, and Zn on allergic inflammation in a murine AR model and to delineate the associated immunological and histopathological responses. Methods: Female BALB/c mice were sensitized with ovalbumin (OVA) and challenged intranasally to induce AR. On days 21–24, the mice were exposed to PM2.5, formaldehyde, and Zn, either individually or in combination with OVA. Allergic symptoms were evaluated through behavioral observation, while immune responses were assessed by analyzing nasal and bronchoalveolar lavage fluids (NALF and BALF), serum immunoglobulin levels, nasal histopathology, and cytokine profiles. Results: Combined exposure to PM2.5, formaldehyde, and Zn significantly intensified allergic inflammation compared with single exposures. Coexposure to PM2.5 and Zn led to synergistic increases in total and OVA-specific immunoglobulin E levels, eosinophilic infiltration, nasal rubbing, sneezing, and Th2/Th17 cytokine levels in NALF and BALF. Histological analysis demonstrated epithelial thickening and goblet cell hyperplasia after combined exposure. Other combinations, including PM2.5 with formaldehyde, also produced additive or modestly amplified inflammatory responses. Conclusions Coexposure to PM2.5, formaldehyde, and Zn aggravated allergic inflammation in an OVA-induced murine model, with PM2.5+Zn yielding the strongest synergistic effects. These findings emphasize the role of pollutant–pollutant interactions in allergic airway diseases and highlight the need for further research to clarify long-term health effects and relevance to human disease.

Background/Aims: Various expanded criteria (EC) for liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) have been proposed to avoid the narrow nature of the Milan criteria (MC). To investigate which EC predicts more favorable outcomes in terms of overall survival (OS) and recurrence-free survival (RFS), we conducted a network meta-analysis (NMA). Methods: A database search was conducted on PubMed, Embase, and the Cochrane Library, to identify studies comparing OS and RFS between patients within the MC and those exceeding the MC but within the EC. Hazard ratios (HRs) were pooled using a random-effects NMA and validated in an in-house cohort of 1,008 LT recipients. Results: Among 22,466 articles identified, 35 studies with 45 pairwise comparisons were included in the NMA along with 8 different EC. The University of California San Francisco (HR, 1.43; 95% CI, 1.19–1.71), Up-to-Seven (HR, 1.50; 95% CI, 1.15–1.97), and Hangzhou criteria (HR, 1.69; 95% CI, 1.11–2.57) showed inferior OS to the MC. The MC ranked highest for both OS and RFS, followed by Metroticket 2.0 for OS and the Asan criteria for RFS. In the validation cohort, both Metroticket 2.0 and AFP model yielded more favorable HCC-specific mortality than other EC. Conclusions Several EC, of which those of Metroticket 2.0 were the best, yielded comparable outcomes to the MC. AFP-based EC such as Metroticket 2.0 and AFP model appeared to be useful in both the NMA and the validation cohort, suggesting a potential role in identifying selected low-risk patients beyond the MC.

Purpose: Metabolic syndrome (MetS) is a condition in which multiple risk factors interact in a complex manner. Considerable attention has been directed towards the potential genetic contributions to its diverse mechanisms. Understanding these contributions is essential for reducing MetS and other chronic diseases and developing effective prevention strategies.Therefore, this study analyzed the research trends in academic papers exploring genetic factors related to MetS and its components in Koreans and attempted to identify areas requiring additional research. Methods: The scoping review method was used to evaluate studies that utilized the secondary data sets comprising the Korean Genome and Epidemiology Study. Articles published over the past 15 years were identified using the Research Information Sharing Service, Korean Studies Information Service System, DBpia, PubMed, and ScienceDirect databases. Results: Forty-seven published articles from 2010 to 2024 were included in the review.Research on the genetic factors linked to MetS has expanded since 2019, indicating significant advances in the field. The research included 18 studies on the polygenic risk score (PRS)/genetic risk score (GRS), 17 studies on single nucleotide polymorphisms (SNPs), six studies on two or more genes, four studies on DNA methylation, and two studies on copy number variations (CNVs). In PRS/GRS research, seven studies focused on the genes related to diseases. In SNP research, four studies examined the FTO gene. Studies on two or more genes included two studies, each on the genes associated with diabetes and high-density lipoprotein cholesterol. For DNA methylation, three studies focused on the TXNIP gene. Finally, in CNV research, one study was conducted on the LEPR gene and one on genes for hypertension. Conclusion The relatively low proportion of studies on DNA methylation and CNV presents limitations in understanding their associations with MetS. Expanded research utilizing diverse approaches and genetic variables is needed to overcome these limitations.

Four soluble factors—putrescine, glucosamine, nicotinamide, and signal transducer and activator of transcription 3 (STAT3) inhibitor BP-1-102—were shown to differentiate bone marrow mononucleated cells (BMNCs) into functional insulin-producing cells (IPCs) in vitro. Transplantation of these IPCs improved hyperglycemia in diabetic mice. However, the role of endogenous BMNC regeneration in this effect was unclear. This study aimed to evaluate the effect of these factors on in vivo BMNC differentiation into IPCs in diabetic mice. Mice were orally administered the factors for 5 days, twice at 2-week intervals, and monitored for 45–55 days. Glucose tolerance, glucose-stimulated insulin secretion, and pancreatic insulin content were measured. Chimeric mice harboring BMNCs from insulin promoter luciferase/green fluorescent protein (GFP) transgenic mice were used to track endogenous BMNC fate. These factors lowered blood glucose levels, improved glucose tolerance, and enhanced insulin secretion. Immunostaining confirmed IPCs in the pancreas, showing the potential of these factors to induce β-cell regeneration and improve diabetes treatment.

Background: The associations between thyroid cancer and skeletal outcomes have not been thoroughly investigated. We aimed to investigate the risk of osteoporotic fractures in patients with thyroid cancer compared to that in a matched control group. Methods: This retrospective cohort study included 2,514 patients with thyroid cancer and 75,420 matched controls from the Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC, 2006–2019). The rates of osteoporotic fractures were analyzed, and associations with the levothyroxine dose were evaluated. Results: Patients with thyroid cancer had a significantly lower risk of fracture than did the control group (hazard ratio [HR], 0.81; 95% confidence interval [CI], 0.69 to 0.94; P=0.006). Patients diagnosed with thyroid cancer after the age of 50 years (older cancer group) had a significantly lower risk of fracture than did those in the control group (HR, 0.72; 95% CI, 0.6 to 0.85; P<0.001), especially those diagnosed with spinal fractures (HR, 0.66; 95% CI, 0.51 to 0.85; P=0.001). Patients in the older cancer group started osteoporosis treatment earlier than did those in the control group (65.5±7.5 years vs. 67.3±7.6 years, P<0.001). Additionally, a lower dose of levothyroxine was associated with a reduced risk of fractures. Conclusion In the clinical setting, the risk of fracture in women diagnosed with thyroid cancer after the age of 50 years was lower than that in the control group, which was caused by more proactive osteoporosis treatment in postmenopausal women with thyroid cancer.

Background/Aims: Inaccurate prediction of lymph node metastasis (LNM) may lead to unnecessary surgery following endoscopic resection of T1 colorectal cancer (CRC). We aimed to validate the usefulness of artificial intelligence (AI) models for predicting LNM in patients with T1 CRC. Methods: We analyzed the clinical data, laboratory results, pathological reports, and endoscopic findings of patients who underwent radical surgery for T1 CRC. We developed AI models to predict LNM using four algorithms: regularized logistic regression classifier (RLRC), random forest classifier (RFC), CatBoost classifier (CBC), and the voting classifier (VC). Four histological factors and four endoscopic findings were included to develop AI models. Areas under the receiver operating characteristics curves (AUROCs) were measured to distinguish AI model performance in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines. Results: Among 1,386 patients with T1 CRC, 173 patients (12.5%) had LNM. The AUROC values of the RLRC, RFC, CBC, and VC models for LNM prediction were significantly higher (0.673, 0.640, 0.679, and 0.677, respectively) than the 0.525 suggested in accordance with the Japanese Society for Cancer of the Colon and Rectum guidelines (vs RLRC, p<0.001; vs RFC, p=0.001; vs CBC, p<0.001; vs VC, p<0.001). The AUROC value was similar between T1 colon versus T1 rectal cancers (0.718 vs 0.615, p=0.700). The AUROC value was also similar between the initial endoscopic resection and initial surgery groups (0.581 vs 0.746, p=0.845). Conclusions AI models trained on the basis of endoscopic findings and pathological features performed well in predicting LNM in patients with T1 CRC regardless of tumor location and initial treatment method.

Objective: The treatment rate for alcohol use disorder (AUD) in Korea is significantly lower than its prevalence rate. Because untreated AUD can have harmful consequences, it is important to identify the factors that contribute to individuals with AUD seeking mental health services. Methods: We collected nationally representative data from the National Mental Health Survey of Korea 2021 and analyzed responses from 643 individuals with AUD, of which 76.8% were male. Factors related to mental health service utilization among individuals with AUD were classified into three categories: sociodemographic (such as sex, age, marital status, education, and monthly household income), clinical (including symptom severity, psychiatric comorbidity, suicidality, and physical illness), and psychological characteristics (like perceived stigma, loneliness and social isolation, and resilience). We used multiple logistic regression analyses to examine each characteristic separately and combined in a single model to determine the most significant factors. Results: The three logistic regression models revealed that sex, psychiatric comorbidity, physical illness, and perceived stigma are significantly linked to the utilization of mental health services among individuals with AUD. Results from the comprehensive model indicated that only physical illness and perceived stigma have significant associations with mental health service utilization. Conclusion These findings can assist in developing targeted interventions for individuals with AUD.

Purpose: This study compared the diagnostic performance of two attenuation imaging (ATI) modes—low-frequency (3 MHz) and high-frequency (4 MHz)—for assessing hepatic steatosis, with histopathological hepatic fat fraction (HFF) as the reference standard. Methods: This prospective single-center study enrolled participants with suspected metabolic dysfunction-associated steatotic liver disease (MASLD) scheduled for liver biopsy or surgery between June 2023 and June 2024. Attenuation coefficient (AC) values were consecutively measured using low- and high-frequency ATI modes, while the skin-to-region of interest distance (SRD) was measured simultaneously. Spearman correlation analysis evaluated the relationships of AC with HFF and SRD, and linear regression identified factors affecting AC. Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUROC). Results: In total, 119 participants (mean age, 37.2±12.0 years; 87 men) were included, with 73 (61.3%) diagnosed with MASLD. HFF ranged from 0% to 50%. The AC values in the lowfrequency mode were significantly higher than those in the high-frequency mode (0.61 vs. 0.54 dB/cm/MHz, P<0.001). HFF significantly influenced AC in both modes, whereas SRD affected AC only in the high-frequency mode (P<0.001). AC correlated positively with HFF in both modes (r_s≥0.514, P<0.001) and negatively with SRD in the high-frequency mode (r_s=-0.338, P<0.001). The AUROC for hepatic steatosis did not differ significantly between the two modes (0.751 vs. 0.771; P=0.609). Conclusion The low-frequency mode produced higher AC values than the high-frequency mode and demonstrated comparable diagnostic accuracy for assessing hepatic steatosis. Unlike the high-frequency mode, the low-frequency mode was not influenced by SRD.

Objective: The treatment rate for alcohol use disorder (AUD) in Korea is significantly lower than its prevalence rate. Because untreated AUD can have harmful consequences, it is important to identify the factors that contribute to individuals with AUD seeking mental health services. Methods: We collected nationally representative data from the National Mental Health Survey of Korea 2021 and analyzed responses from 643 individuals with AUD, of which 76.8% were male. Factors related to mental health service utilization among individuals with AUD were classified into three categories: sociodemographic (such as sex, age, marital status, education, and monthly household income), clinical (including symptom severity, psychiatric comorbidity, suicidality, and physical illness), and psychological characteristics (like perceived stigma, loneliness and social isolation, and resilience). We used multiple logistic regression analyses to examine each characteristic separately and combined in a single model to determine the most significant factors. Results: The three logistic regression models revealed that sex, psychiatric comorbidity, physical illness, and perceived stigma are significantly linked to the utilization of mental health services among individuals with AUD. Results from the comprehensive model indicated that only physical illness and perceived stigma have significant associations with mental health service utilization. Conclusion These findings can assist in developing targeted interventions for individuals with AUD.