Nam Hoon Kim

@korea.ac.kr

Endocrinology, Internal Medicine
Korea University College of Medicine

RESEARCH INTERESTS

Diabetes, Obesity, Lipid metabolism

115

Scopus Publications

Scopus Publications

  • Efficacy and tolerability of initial triple combination therapy with metformin, dapagliflozin and saxagliptin compared with stepwise add-on therapy in drug-naïve patients with type 2 diabetes (TRIPLE-AXEL study): A multicentre, randomized, 104-week, open-label, active-controlled trial
    Nam Hoon Kim, Jun Sung Moon, Yong‐ho Lee, Ho Chan Cho, Soo Heon Kwak, Soo Lim, Min Kyong Moon, Dong‐Lim Kim, Tae Ho Kim, Eunvin Ko,et al.

    Wiley
    AbstractAimTo evaluate the efficacy and tolerability of an initial triple combination therapy (TCT) compared with conventional stepwise add‐on therapy (SAT) in patients with newly diagnosed type 2 diabetes (T2D).Materials and MethodsThis multicentre, randomized, 104‐week, open‐label trial randomized 105 patients with drug‐naïve T2D (with HbA1c level ≥ 8.0%, < 11.0%) to the TCT (1000 mg of metformin, 10 mg of dapagliflozin and 5 mg of saxagliptin once daily) or SAT (initiated with metformin, followed by glimepiride and sitagliptin) groups. The primary outcome was the proportion of patients who achieved an HbA1c level of less than 6.5% without hypoglycaemia, weight gain of 5% or higher, or discontinuation of drugs because of adverse events at week 104.ResultsHbA1c reduction from baseline at week 104 was similar between the groups (the least squares mean change was −2.56% in the TCT group vs. –2.75% in the SAT group). The primary outcome was achieved in 39.0% and 17.1% of the TCT and SAT groups, respectively, with a risk difference of 22.0 (95% confidence interval 3.0, 40.8; P = .027). HbA1c level less than 6.5% at week 104 was 46.3% in both the TCT and SAT groups, whereas the incidence of hypoglycaemia, weight gain, or discontinuation of drugs was 16.7% and 62.0% in the TCT and SAT groups, respectively (P < .001). TCT was well‐tolerated and had fewer adverse events than SAT.ConclusionsAmong newly diagnosed patients with T2D, initial TCT effectively lowered HbA1c levels with higher tolerability and safety than SAT for 104 weeks, suggesting a novel strategy for initial combination therapy in T2D patients.

  • 2023 Clinical Practice Guidelines for Diabetes Management in Korea: Full Version Recommendation of the Korean Diabetes Association
    Jun Sung Moon, Shinae Kang, Jong Han Choi, Kyung Ae Lee, Joon Ho Moon, Suk Chon, Dae Jung Kim, Hyun Jin Kim, Ji A Seo, Mee Kyoung Kim,et al.

    Korean Diabetes Association

  • 2023 Diabetic Kidney Disease Fact Sheet in Korea
    Nam Hoon Kim, Mi-Hae Seo, Jin Hyung Jung, Kyung Do Han, Mi Kyung Kim, Nan Hee Kim, and

    Korean Diabetes Association
    Background: To investigate the prevalence, incidence, comorbidities, and management status of diabetic kidney disease (DKD) and diabetes-related end-stage kidney disease (ESKD) in South Korea.Methods: We used the Korea National Health and Nutrition Examination Survey data (2019 to 2021, <i>n</i>=2,665) for the evaluation of prevalence, comorbidities, control rate of glycemia and comorbidities in DKD, and the Korean Health Insurance Service-customized database (2008 to 2019, <i>n</i>=3,950,857) for the evaluation of trends in the incidence and prevalence rate of diabetes-related ESKD, renin-angiotensin system (RAS) blockers and sodium glucose cotransporter 2 (SGLT2) inhibitors use for DKD, and the risk of atherosclerotic cardiovascular disease (ASCVD) and mortality according to DKD stages. DKD was defined as albuminuria or low estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m<sup>2</sup> in patients with diabetes mellitus.Results: The prevalence of DKD was 25.4% (albuminuria, 22.0%; low eGFR, 6.73%) in patients with diabetes mellitus aged ≥30 years. Patients with DKD had a higher rate of comorbidities, including hypertension, dyslipidemia, and central obesity; however, their control rates were lower than those without DKD. Prescription rate of SGLT2 inhibitors with reduced eGFR increased steadily, reaching 5.94% in 2019. Approximately 70% of DKD patients were treated with RAS blockers. The prevalence rate of diabetesrelated ESKD has been steadily increasing, with a higher rate in older adults. ASCVD and mortality were significantly associated with an in increase in DKD stage.Conclusion: DKD is prevalent among Korean patients with diabetes and is an independent risk factor for cardiovascular morbidity and mortality, which requiring intensive management of diabetes and comorbidities. The prevalence of diabetes-related ESKD has been increasing, especially in the older adults, during past decade.

  • Real-World Treatment Patterns according to Clinical Practice Guidelines in Patients with Type 2 Diabetes Mellitus and Established Cardiovascular Disease in Korea: Multicenter, Retrospective, Observational Study
    Ye Seul Yang, Nam Hoon Kim, Jong Ha Baek, Seung-Hyun Ko, Jang Won Son, Seung-Hwan Lee, Sang Youl Rhee, Soo-Kyung Kim, Tae Seo Sohn, Ji Eun Jun,et al.

    Korean Diabetes Association
    Background: Recent diabetes management guidelines recommend that sodium-glucose cotransporter 2 inhibitors (SGLT2is) or glucagon-like peptide 1 receptor agonists (GLP-1RAs) with proven cardiovascular benefits should be prioritized for combination therapy in patients with type 2 diabetes mellitus (T2DM) and established cardiovascular disease (CVD). This study was aimed at evaluating SGLT2i or GLP-1RA usage rates and various related factors in patients with T2DM and established CVD.Methods: We enrolled adults with T2DM aged ≥30 years who were hospitalized due to established CVD from January 2019 to May 2020 at 13 secondary and tertiary hospitals in Korea in this retrospective observational study.Results: Overall, 2,050 patients were eligible for analysis among 2,107 enrolled patients. The mean patient age, diabetes duration, and glycosylated hemoglobin level were 70.0 years, 12.0 years, and 7.5%, respectively. During the mean follow-up duration of 9.7 months, 25.7% of the patients were prescribed SGLT2is after CVD events. However, only 1.8% were prescribed GLP-1RAs. Compared with SGLT2i non-users, SGLT2i users were more frequently male and obese. Furthermore, they had a shorter diabetes duration but showed worse glycemic control and better renal function at the time of the event. GLP-1RA users had a longer duration of diabetes and worse glycemic control at the time of the event than GLP-1RA non-users.Conclusion: The SGLT2i or GLP-1RA prescription rates were suboptimal in patients with T2DM and established CVD. Sex, body mass index, diabetes duration, glycemic control, and renal function were associated with the use of these agents.

  • Associations of omega-3 fatty acids vs. fenofibrate with adverse cardiovascular outcomes in people with metabolic syndrome: propensity matched cohort study
    Nam Hoon Kim, Ji Yoon Kim, Jimi Choi, and Sin Gon Kim

    Oxford University Press (OUP)
    Abstract Aims Omega-3 fatty acids and fenofibrates have shown some beneficial cardiovascular effects; however, their efficacy has not been compared. This study aimed to compare the effectiveness of currently available omega-3 fatty acids and fenofibrate for reducing major adverse cardiovascular events (MACE). Methods and results From a nationwide population-based cohort in South Korea (2008–2019), individuals with metabolic syndrome (≥30 years) who received statin with omega-3 fatty acids and those receiving statin with fenofibrate were matched by propensity score (n = 39 165 in both groups). The primary outcome was MACE, including ischaemic heart disease (IHD), ischaemic stroke (IS), and death from cardiovascular causes. The risk of MACE was lower [hazard ratio (HR), 0.79; 95% confidence interval (CI), 0.74–0.83] in the fenofibrate group than in the omega-3 fatty acid group. Fenofibrate was associated with a lower incidence of IHD (HR, 0.72; 95% CI, 0.67–0.77) and hospitalization for heart failure (HR, 0.90; 95% CI, 0.82–0.97), but not IS (HR, 0.90; 95% CI, 0.81–1.00) nor death from cardiovascular causes (HR, 1.07; 95% CI, 0.97–1.17). The beneficial effect of fenofibrate compared to omega-3 fatty acids was prominent in patients with preexisting atherosclerotic cardiovascular disease and those receiving lower doses of omega-3 fatty acids (≤2 g per day). Conclusion In a real-world setting, fenofibrate use was associated with a lower risk of MACE compared with low-dose omega-3 fatty acids when added to statins in people with metabolic syndrome.

  • Cancer Risk in Graves Disease with Radioactive 131I Treatment: A Nationwide Cohort Study
    Kyeong Jin Kim, Jimi Choi, Kyoung Jin Kim, Eyun Song, Ji Hee Yu, Nam Hoon Kim, Hye Jin Yoo, Ji A Seo, Nan Hee Kim, Kyung Mook Choi,et al.

    Society of Nuclear Medicine
    Visual Abstract Radioactive 131I (RAI) therapy has potential effects for the treatment of Graves disease (GD). However, whether RAI therapy for GD increases cancer risk remains controversial in medicine and public health. We aimed to investigate whether the risk of cancer increases in patients with GD receiving RAI therapy compared with those who did not. Methods: We used the Korean National Health Insurance Service’s National Health Information Database from 2004 to 2020 and defined GD as prescribing antithyroid drugs, RAI, or thyroidectomy as a treatment for GD (International Classification of Diseases, 10th revision, E05 group). We investigated the hazard ratios (HRs) of overall and site-specific cancers associated with RAI in patients with GD. Subsequent cancer was defined as a primary malignancy treated at least 1 y after RAI therapy. Results: In total, 10,737 patients with GD who received RAI therapy (7,193 women, 67.0%; mean age, 43.7 ± 13.4 y) were matched to 53,003 patients with GD who had never received RAI treatment (35,471 women, 66.9%; mean age, 43.8 ± 13.2 y) in a 1:4–5 ratio by age, sex, and health checkup data. The median follow-up duration was 8.7 y (interquartile range, 5.2–12.1 y), and the median cumulative RAI dose was 555 MBq (interquartile range, 370–630 MBq) in the RAI therapy group. During 2004–2020, the overall subsequent cancer rates were 5.66 and 5.84 per 1,000 person-years in the RAI and non-RAI groups, respectively, with an unadjusted HR of 0.97 (95% CI, 0.88–1.06); this remained at 0.96 (95% CI, 0.83–1.10) after adjustment for multiple clinical confounding factors. For cancer subtypes, the risk of leukemia was significantly increased, with an HR of 2.39 (95% CI, 1.17–4.91). However, a loss of statistical significance was observed after adjusting for confounding factors, which may be attributed to the limited number of absolute events. Moreover, cancer-specific mortality was not different between the RAI and the non-RAI groups, with an adjusted HR of 0.99 (95% CI, 0.66–1.47). Conclusion: This study identified that the overall cancer risk in patients with GD who received RAI therapy compared with those who did not was not significant in Korea. Further long-term studies are needed to determine the risks and advantages of RAI therapy in patients with GD.

  • Initial Combination Therapy in Type 2 Diabetes
    Ji Yoon Kim and Nam Hoon Kim

    Korean Endocrine Society
    Type 2 diabetes (T2D) is a progressive disease in which it is challenging to achieve long-term durable glycemic control. However, intensive glycemic control is crucial for preventing diabetes-related complications. Previous studies showed that monotherapy with a stepwise add-on approach was seldom effective for long-term durable glycemic control. Combination therapy, which refers to the use of two or more drugs to control hyperglycemia, has multiple benefits, including the ability to target a variety of pathophysiological processes underlying hyperglycemia. In clinical trials, initial combination therapy showed better glycemic control than monotherapy or a stepwise approach. Emerging evidence indicates that initial combination therapy is associated with preserved β-cell function and fewer complications in T2D. However, cost-effectiveness and adverse events with combination therapy are issues that should be considered. Therefore, initial combination therapy is an important option for patients with T2D that clinicians should consider with a view toward balancing benefits and potential harms. In this review, we summarize the literature addressing initial combination therapy in T2D, and we suggest optimal strategies based on clinical situations and patient characteristics.

  • Attention to Innate Circadian Rhythm and the Impact of Its Disruption on Diabetes
    Da Young Lee, Inha Jung, So Young Park, Ji Hee Yu, Ji A Seo, Kyeong Jin Kim, Nam Hoon Kim, Hye Jin Yoo, Sin Gon Kim, Kyung Mook Choi,et al.

    Korean Diabetes Association
    Novel strategies are required to reduce the risk of developing diabetes and/or clinical outcomes and complications of diabetes. In this regard, the role of the circadian system may be a potential candidate for the prevention of diabetes. We reviewed evidence from animal, clinical, and epidemiological studies linking the circadian system to various aspects of the pathophysiology and clinical outcomes of diabetes. The circadian clock governs genetic, metabolic, hormonal, and behavioral signals in anticipation of cyclic 24-hour events through interactions between a “central clock” in the suprachiasmatic nucleus and “peripheral clocks” in the whole body. Currently, circadian rhythmicity in humans can be subjectively or objectively assessed by measuring melatonin and glucocorticoid levels, core body temperature, peripheral blood, oral mucosa, hair follicles, rest-activity cycles, sleep diaries, and circadian chronotypes. In this review, we summarized various circadian misalignments, such as altered light-dark, sleep-wake, rest-activity, fasting-feeding, shift work, evening chronotype, and social jetlag, as well as mutations in clock genes that could contribute to the development of diabetes and poor glycemic status in patients with diabetes. Targeting critical components of the circadian system could deliver potential candidates for the treatment and prevention of type 2 diabetes mellitus in the future.

  • Clinical and Lifestyle Determinants of Continuous Glucose Monitoring Metrics in Insulin-Treated Patients with Type 2 Diabetes Mellitus
    Da Young Lee, Namho Kim, Inha Jung, So Young Park, Ji Hee Yu, Ji A Seo, Jihee Kim, Kyeong Jin Kim, Nam Hoon Kim, Hye Jin Yoo,et al.

    Korean Diabetes Association
    Background: There was limited evidence to evaluate the association between lifestyle habits and continuous glucose monitoring (CGM) metrics. Thus, we aimed to depict the behavioral and metabolic determinants of CGM metrics in insulin-treated patients with type 2 diabetes mellitus (T2DM).Methods: This is a prospective observational study. We analyzed data from 122 insulin-treated patients with T2DM. Participants wore Dexcom G6 and Fitbit, and diet information was identified for 10 days. Multivariate-adjusted logistic regression analysis was performed for the simultaneous achievement of CGM-based targets, defined by the percentage of time in terms of hyper, hypoglycemia and glycemic variability (GV). Intake of macronutrients and fiber, step counts, sleep, postprandial C-peptide-to-glucose ratio (PCGR), information about glucose lowering medications and metabolic factors were added to the analyses. Additionally, we evaluated the impact of the distribution of energy and macronutrient during a day, and snack consumption on CGM metrics.Results: Logistic regression analysis revealed that female, participants with high PCGR, low glycosylated hemoglobin (HbA1c) and daytime step count had a higher probability of achieving all targets based on CGM (odds ratios [95% confidence intervals] which were 0.24 [0.09 to 0.65], 1.34 [1.03 to 1.25], 0.95 [0.9 to 0.99], and 1.15 [1.03 to 1.29], respectively). And participants who ate snacks showed a shorter period of hyperglycemia and less GV compared to those without.Conclusion: We confirmed that residual insulin secretion, daytime step count, HbA1c, and women were the most relevant determinants of adequate glycemic control in insulin-treated patients with T2DM. In addition, individuals with snack consumption were exposed to lower times of hyperglycemia and GV.

  • Comparison of on-Statin Lipid and Lipoprotein Levels for the Prediction of First Cardiovascular Event in Type 2 Diabetes Mellitus
    Ji Yoon Kim, Jimi Choi, Sin Gon Kim, and Nam Hoon Kim

    Korean Diabetes Association
    Background: A substantial cardiovascular disease risk remains even after optimal statin therapy. Comparative predictiveness of major lipid and lipoprotein parameters for cardiovascular events in patients with type 2 diabetes mellitus (T2DM) who are treated with statins is not well documented.Methods: From the Korean Nationwide Cohort, 11,900 patients with T2DM (≥40 years of age) without a history of cardiovascular disease and receiving moderate- or high-intensity statins were included. The primary outcome was the first occurrence of major adverse cardiovascular events (MACE) including ischemic heart disease, ischemic stroke, and cardiovascular death. The risk of MACE was estimated according to on-statin levels of low-density lipoprotein cholesterol (LDL-C), triglyceride (TG), highdensity lipoprotein cholesterol (HDL-C), and non-HDL-C.Results: MACE occurred in 712 patients during a median follow-up period of 37.9 months (interquartile range, 21.7 to 54.9). Among patients achieving LDL-C levels less than 100 mg/dL, the hazard ratios for MACE per 1-standard deviation change in ontreatment values were 1.25 (95% confidence interval [CI], 1.07 to 1.47) for LDL-C, 1.31 (95% CI, 1.09 to 1.57) for non-HDL-C, 1.05 (95% CI, 0.91 to 1.21) for TG, and 1.16 (95% CI, 0.98 to 1.37) for HDL-C, after adjusting for potential confounders and lipid parameters mutually. The predictive ability of on-statin LDL-C and non-HDL-C for MACE was prominent in patients at high cardiovascular risk or those with LDL-C ≥70 mg/dL.Conclusion: On-statin LDL-C and non-HDL-C levels are better predictors of the first cardiovascular event than TG or HDL-C in patients with T2DM.

  • The Efficacy and Safety of Moderate-Intensity Rosuvastatin with Ezetimibe versus High-Intensity Rosuvastatin in High Atherosclerotic Cardiovascular Disease Risk Patients with Type 2 Diabetes Mellitus: A Randomized, Multicenter, Open, Parallel, Phase 4 Study
    Jun Sung Moon, Il Rae Park, Sang Soo Kim, Hye Soon Kim, Nam Hoon Kim, Sin Gon Kim, Seung Hyun Ko, Ji Hyun Lee, Inkyu Lee, Bo Kyeong Lee,et al.

    Korean Diabetes Association
    Background: To investigate the efficacy and safety of moderate-intensity rosuvastatin/ezetimibe combination compared to highintensity rosuvastatin in high atherosclerotic cardiovascular disease (ASCVD) risk patients with type 2 diabetes mellitus (T2DM).Methods: This study was a randomized, multicenter, open, parallel phase 4 study, and enrolled T2DM subjects with an estimated 10-year ASCVD risk ≥7.5%. The primary endpoint was the low-density lipoprotein cholesterol (LDL-C) change rate after 24-week rosuvastatin 10 mg/ezetimibe 10 mg treatment was non-inferior to that of rosuvastatin 20 mg. The achievement proportion of 10-year ASCVD risk <7.5% or comprehensive lipid target (LDL-C <70 mg/dL, non-high-density lipoprotein cholesterol <100 mg/dL, and apolipoprotein B <80 mg/dL) without discontinuation, and several metabolic parameters were explored as secondary endpoints.Results: A hundred and six participants were assigned to each group. Both groups showed significant reduction in % change of LDL-C from baseline at week 24 (–63.90±6.89 vs. –55.44±6.85, combination vs. monotherapy, <i>p</i>=0.0378; respectively), but the combination treatment was superior to high-intensity monotherapy in LDL-C change (%) from baseline (least square [LS] mean difference, –8.47; 95% confidence interval, –16.44 to –0.49; <i>p</i>=0.0378). The combination treatment showed a higher proportion of achieved comprehensive lipid targets rather than monotherapy (85.36% vs. 62.22% in monotherapy, <i>p</i>=0.015). The ezetimibe combination significantly improved homeostasis model assessment of β-cell function even without A1c changes (LS mean difference, 17.13; <i>p</i>=0.0185).Conclusion: In high ASCVD risk patients with T2DM, the combination of moderate-intensity rosuvastatin and ezetimibe was not only non-inferior but also superior to improving dyslipidemia with additional benefits compared to high-intensity rosuvastatin monotherapy.

  • Inhibition of adipose tissue angiogenesis prevents rebound weight gain after caloric restriction in mice fed a high-fat diet
    Hye-Jin Lee, Bo-Yeong Jin, Mi-Rae Park, Nam Hoon Kim, Kwan Sik Seo, Yong Taek Jeong, Tsutomu Wada, Jun-Seok Lee, Sang-Hyun Choi, and Dong-Hoon Kim

    Elsevier BV

  • Additive impact of diabetes and sarcopenia on all-cause and cardiovascular mortality: A longitudinal nationwide population-based study
    Eyun Song, Soon Young Hwang, Min Jeong Park, Ahreum Jang, Kyeong Jin Kim, Ji Hee Yu, Nam Hoon Kim, Hye Jin Yoo, Ji A. Seo, Sin Gon Kim,et al.

    Elsevier BV

  • Weight-adjusted waist as an integrated index for fat, muscle and bone health in adults
    Kyoung Jin Kim, Serhim Son, Kyeong Jin Kim, Sin Gon Kim, and Nam Hoon Kim

    Wiley
    AbstractBackgroundUnhealthy body composition, including high fat mass, low muscle mass and low bone mass, is a critical health issue in adults. The weight‐adjusted waist index (WWI) estimates fat and muscle mass and may have implications for bone health. We examined its association with body composition outcomes in a large Korean adult cohort.MethodsThis study used data from the Korean National Health and Nutrition Examination Survey (2008–2011). WWI was calculated as waist circumference (cm) divided by the square root of body weight (kg). Dual‐energy X‐ray absorptiometry was used to measure bone mineral density (BMD), appendicular lean mass (ALM) and total body fat percentage. Unhealthy body composition was defined as combined presence of high fat mass, low bone mass and low muscle mass.ResultsA total of 5983 individuals (3034 men [50.7%] and 2949 women [49.3%]; mean age: 63.5 ± 8.7 years) were included. WWI was positively correlated with total body fat percentage (r = 0.478, P < 0.001) and inversely with ALM/weight (r = −0.485, P < 0.001) and BMD at the lumbar spine (r = −0.187, P < 0.001), femoral neck (r = −0.269, P < 0.001) and total hip (r = −0.255, P < 0.001). Higher WWI quartiles correlated with lower BMD, T‐scores and ALM/weight, along with increased total body fat, evident in both genders and more pronounced in women, even after adjusting for confounders. This trend remained statistically significant across WWI quartiles for all analyses (P < 0.001). Higher WWI quartiles were also significantly associated with higher odds of unhealthy body composition, with adjusted odds ratio in the highest WWI group of 18.08 (95% CI, 4.32–75.61) in men and 6.36 (95% CI, 3.65–11.07) in women. The optimal cutoff values of WWI for unhealthy body composition were 10.4 cm/√kg in men and 10.5 cm/√kg in women.ConclusionsIn community‐dwelling adults, high WWI values are associated with unfavourable body composition outcomes, indicating high fat mass, low muscle mass and low bone mass. WWI can potentially serve as an integrated index of body composition, underscoring the need for further research to validate its use in clinical settings.

  • 2023 Clinical Practice Guidelines for Diabetes Mellitus of the Korean Diabetes Association
    Jong Han Choi, Kyung Ae Lee, Joon Ho Moon, Suk Chon, Dae Jung Kim, Hyun Jin Kim, Nan Hee Kim, Ji A Seo, Mee Kyoung Kim, Jeong Hyun Lim,et al.

    Korean Diabetes Association
    In May 2023, the Committee of Clinical Practice Guidelines of the Korean Diabetes Association published the revised clinical practice guidelines for Korean adults with diabetes and prediabetes. We incorporated the latest clinical research findings through a comprehensive systematic literature review and applied them in a manner suitable for the Korean population. These guidelines are designed for all healthcare providers nationwide, including physicians, diabetes experts, and certified diabetes educators who manage patients with diabetes or individuals at risk of developing diabetes. Based on recent changes in international guidelines and the results of a Korean epidemiological study, the recommended age for diabetes screening has been lowered. In collaboration with the relevant Korean medical societies, recently revised guidelines for managing hypertension and dyslipidemia in patients with diabetes have been incorporated into this guideline. An abridgment containing practical information on patient education and systematic management in the clinic was published separately.


  • All-cause and cause-specific mortality risks associated with calcium supplementation with or without vitamin D: A nationwide population-based study
    Kyoung Jin Kim, Jimi Choi, Kyeong Jin Kim, Nam Hoon Kim, and Sin Gon Kim

    Wiley
    BACKGROUND Current evidence regarding the mortality outcomes associated with calcium supplementation with or without low dose vitamin D is conflicting. OBJECTIVES To investigate the effects of calcium supplementation with or without vitamin D on all-cause and cause-specific mortalities in a large-scale cohort. METHODS This study used data from the Korean National Health Insurance System database and National Death Registry. A total of 27,846 participants aged >55 years who had taken calcium supplements with or without vitamin D for at least 90 days (calcium supplementation only [CaO], n = 6,256; calcium supplementation in combination with vitamin D [CaD], n = 21,590) were matched in a 1:1 ratio to those who did not take calcium or vitamin D supplements (control group) using propensity scores. RESULTS No difference in all-cause mortality risk was found between the CaO and control groups. [adjusted hazard ratio (HR) = 1.00; 95% confidence interval (CI): 0.92-1.10]. However, all-cause mortality was lower in the CaD group [HR = 0.85; 95% CI: 0.80-0.89] compared with that in the control group. Mortality risk associated with cardiovascular disease (CVD) was decreased in the CaD group when the daily vitamin D dose received was less than 1,000 IU [HR = 0.72; 95% CI: 0.64-0.81]. Subgroup analysis showed significant effect of vitamin D with calcium in individuals who were female, aged ≥65 years, or had previous history of cancer or CVD. CONCLUSION In combination with calcium, vitamin D supplementation provides better outcomes for all-cause mortality, particularly cardiovascular-associated mortality, in a duration-dependent manner. This article is protected by copyright. All rights reserved.

  • A Novel Anthropometric Parameter, Weight-Adjusted Waist Index Represents Sarcopenic Obesity in Newly Diagnosed Type 2 Diabetes Mellitus
    Min Jeong Park, Soon Young Hwang, Nam Hoon Kim, Sin Gon Kim, Kyung Mook Choi, Sei Hyun Baik, and Hye Jin Yoo

    Korean Society for the Study of Obesity
    Background As the metabolic significance of sarcopenic obesity (SO) is revealed, finding an appropriate index to detect SO is important, especially for type 2 diabetes mellitus (T2DM) patients with accompanying metabolic dysfunction. Methods Participants (n=515) from the Korea Guro Diabetes Program were included to compare how well waist circumference (WC), waist hip ratio (WHR), waist height ratio (WHtR), and the weight-adjusted waist index (WWI) predict SO in newly diagnosed T2DM patients. Sarcopenia was defined based on guidelines from the 2019 Asian Working Group for Sarcopenia as both low muscle mass (appendicular skeletal muscle [ASM]/height2 <7.0 kg/m2 for men, <5.4 kg/m2 for women) and strength (handgrip strength <28.0 kg for men, <18.0 kg for women) and/or reduced physical performance (gait speed <1.0 m/sec). Obesity was defined as a WC ≥90 cm in men and ≥85 cm in women. The WHR, WHtR, and WWI were calculated by dividing the WC by the hip circumference, height, and √ weight, respectively. Results The WC, WHR, and WHtR correlated positively with the fat and muscle mass represented by truncal fat amount (TFA) and ASM, whereas the WWI was proportional to the TFA and inversely related to ASM. Of the four indices, the WWI showed the highest area under the receiver operative characteristic curve for SO. The WWI also exhibited a positive correlation with albuminuria and the mean brachial-ankle pulse wave velocity, especially in patients aged ≥65 years. Conclusion The WWI is the preferable anthropometric index for predicting SO in T2DM patients, and it might be a proper index for predicting cardiometabolic risk factors in elderly people.

  • Linear association between radioactive iodine dose and second primary malignancy risk in thyroid cancer
    Kyeong Jin Kim, Kyoung Jin Kim, Jimi Choi, Nam Hoon Kim, and Sin Gon Kim

    Oxford University Press (OUP)
    Abstract Background We aimed to investigate whether the risk of second primary malignancy (SPM) in patients with thyroid cancer (TC) receiving radioactive iodine (RAI) therapy rises in a cumulative, dose-dependent manner compared with those not undergoing RAI. Methods Using the Korean National Health Insurance Service National Health Information Database (2002-2019), we investigated hazard ratios of SPM associated with RAI in TC. SPM was defined as a second primary malignancy diagnosed at least 1 year after TC diagnosis. Results Of 217 777 patients with TC (177 385 women and 40 392 men; mean [SD] age, 47.2 [11.6] years), 100 448 (46.1%) received RAI therapy. The median (IQR) follow-up duration was 7.7 (5.5-10.3) years, and the median (IQR) cumulative RAI dose was 3.7 (1.9-5.6) GBq. From 2004 to 2019, SPM incidence rates were 7.30 and 6.56 per 1000 person-years in the RAI and non-RAI groups, respectively, with an unadjusted hazard ratio of 1.09 (95% confidence interval = 1.05 to 1.13); this rate remained at 1.08 (95% confidence interval = 1.04 to 1.13) after adjustment for multiple clinical confounding factors. Notably, SPM risk increased significantly, from 3.7 GBq with full adjustments, and a strong linear association between cumulative RAI dose and SPM was observed in the restricted cubic spline analysis. Regarding cancer subtypes, myeloid leukemia and salivary gland, trachea, lung and bronchus, uterus, and prostate cancers were the most significantly elevated risks in patients who underwent RAI therapy. Conclusions This study identified that SPM risk increased linearly in a dose-dependent manner in patients with TC undergoing RAI therapy compared with those not undergoing RAI therapy.

  • Cytarabine induces cachexia with lipid malabsorption via zippering the junctions of lacteal in murine small intestine
    Mi-Rae Park, Hye-Jin Lee, Hye-Min Jang, Nam Hoon Kim, Jun-Seok Lee, Yong Taek Jeong, Inho Kim, Sang-Hyun Choi, Kwan Sik Seo, and Dong-Hoon Kim

    Elsevier BV


  • Association of long-term hyperglycaemia and insulin resistance with brain atrophy and cognitive decline: A longitudinal cohort study
    Ji Hee Yu, Regina E. Y. Kim, So Young Park, Da Young Lee, Hyun Joo Cho, Nam Hoon Kim, Hye Jin Yoo, Ji A Seo, Sin Gon Kim, Kyung Mook Choi,et al.

    Wiley
    To investigate the longitudinal changes in brain volume and cognitive function associated with diabetes at midlife, and to examine whether long‐term hyperglycaemia, insulin resistance or secretory function is associated with brain atrophy and cognitive decline.

  • Effect of a Wearable Device-Based Physical Activity Intervention in North Korean Refugees: Pilot Randomized Controlled Trial
    Ji Yoon Kim, Kyoung Jin Kim, Kyeong Jin Kim, Jimi Choi, Jinhee Seo, Jung-Been Lee, Jae Hyun Bae, Nam Hoon Kim, Hee Young Kim, Soo-Kyung Lee,et al.

    JMIR Publications Inc.
    Background Effective health interventions for North Korean refugees vulnerable to metabolic disorders are currently unelucidated. Objective This study aimed to evaluate the effects of digital health interventions in North Korean refugees using a wearable activity tracker (Fitbit device). Methods We conducted a prospective, randomized, open-label study on North Korean refugees aged 19-59 years between June 2020 and October 2021 with a 12-week follow-up period. The participants were randomly assigned to either an intervention group or a control group in a 1:1 ratio. The intervention group received individualized health counseling based on Fitbit data every 4 weeks, whereas the control group wore the Fitbit device but did not receive individualized counseling. The primary and secondary outcomes were the change in the mean daily step count and changes in the metabolic parameters, respectively. Results The trial was completed by 52 North Korean refugees, of whom 27 and 25 were in the intervention and control groups, respectively. The mean age was 43 (SD 10) years, and 41 (78.8%) participants were women. Most participants (44/52, 95.7%) had a low socioeconomic status. After the intervention, the daily step count in the intervention group increased, whereas that in the control group decreased. However, there were no significant differences between the 2 groups (+83 and –521 steps in the intervention and control groups, respectively; P=.500). The effects of the intervention were more prominent in the participants with a lower-than-average daily step count at baseline (&lt;11,667 steps/day). After the 12-week study period, 85.7% (12/14) and 46.7% (7/15) of the participants in the intervention and control groups, respectively, had an increased daily step count (P=.05). The intervention prevented the worsening of the metabolic parameters, including BMI, waist circumference, fasting blood glucose level, and glycated hemoglobin level, during the study period. Conclusions The wearable device–based physical activity intervention did not significantly increase the average daily step count in the North Korean refugees in this study. However, the intervention was effective among the North Korean refugees with a lower-than-average daily step count; therefore, a large-scale, long-term study of this intervention type in an underserved population is warranted. Trial Registration Clinical Research Information Service KCT0007999; https://cris.nih.go.kr/cris/search/detailSearch.do/23622

  • Serum fibroblast growth factor 1 and its association with pancreatic beta cell function and insulin sensitivity in adults with glucose intolerance
    Ji Yoon Kim, Jimi Choi, Yeongkeun Kwon, Sungsoo Park, Sin Gon Kim, and Nam Hoon Kim

    Frontiers Media SA
    BackgroundBeneficial role of fibroblast growth factor 1 (FGF1) in the regulation of glucose metabolism and adipose tissue remodeling was suggested in rodents. This study aimed to investigate the association between serum FGF1 levels and metabolic parameters in adults with glucose intolerance.MethodsSerum FGF1 levels were examined using an enzyme-linked immunosorbent assay in 153 individuals with glucose intolerance. Associations between serum FGF1 levels and metabolic parameters, including body mass index (BMI), glycated hemoglobin (HbA1c), and 75 g oral glucose tolerance test-derived parameters, including insulinogenic index (IGI), Matsuda insulin sensitivity index (ISI), and disposition index (DI), were examined.ResultsSerum FGF1 was detected in 35 individuals (22.9%), possibly due to the autocrine/paracrine nature of the peptide. IGI and DI levels were significantly lower in individuals with higher FGF1 levels than in those with lower FGF1 levels or undetectable FGF1 (p=0.006 and 0.005 for IGI and DI, respectively, after adjustment for age, sex, and BMI). Univariable and multivariable analyses using the Tobit regression model also revealed a negative association between FGF1 levels and IGI and DI. The regression coefficients per 1-SD of log-transformed IGI and DI were −0.461 (p=0.013) and −0.467 (p=0.012), respectively, after adjustment for age, sex, and BMI. In contrast, serum FGF1 levels were not significantly associated with ISI, BMI, or HbA1c.ConclusionsThe serum concentration of FGF1 was significantly elevated in individuals with low insulin secretion, suggesting a possible interaction between FGF1 and beta cell function in humans.

  • Metformin acts as a dual glucose regulator in mouse brain
    Bo-Yeong Jin, Hyun-Ju Kim, Mi-Jeong Oh, Na-Hee Ha, Yong Taek Jeong, Sang-Hyun Choi, Jun-Seok Lee, Nam Hoon Kim, and Dong-Hoon Kim

    Frontiers Media SA
    Aims: Metformin improves glucose regulation through various mechanisms in the periphery. Our previous study revealed that oral intake of metformin activates several brain regions, including the hypothalamus, and directly activates hypothalamic S6 kinase in mice. In this study, we aimed to identify the direct effects of metformin on glucose regulation in the brain.Materials and methods: We investigated the role of metformin in peripheral glucose regulation by directly administering metformin intracerebroventricularly in mice. The effect of centrally administered metformin (central metformin) on peripheral glucose regulation was evaluated by oral or intraperitoneal glucose, insulin, and pyruvate tolerance tests. Hepatic gluconeogenesis and gastric emptying were assessed to elucidate the underlying mechanisms. Liver-specific and systemic sympathetic denervation were performed.Results: Central metformin improved the glycemic response to oral glucose load in mice compared to that in the control group, and worsened the response to intraperitoneal glucose load, indicating its dual role in peripheral glucose regulation. It lowered the ability of insulin to decrease serum glucose levels and worsened the glycemic response to pyruvate load relative to the control group. Furthermore, it increased the expression of hepatic G6pc and decreased the phosphorylation of STAT3, suggesting that central metformin increased hepatic glucose production. The effect was mediated by sympathetic nervous system activation. In contrast, it induced a significant delay in gastric emptying in mice, suggesting its potent role in suppressing intestinal glucose absorption.Conclusion: Central metformin improves glucose tolerance by delaying gastric emptying through the brain-gut axis, but at the same time worsens it by increasing hepatic glucose production via the brain-liver axis. However, with its ordinary intake, central metformin may effectively enhance its glucose-lowering effect through the brain-gut axis, which could surpass its effect on glucose regulation via the brain-liver axis.