Reactivation of Bone Lining Cells are Attenuated Over Repeated Anti-sclerostin Antibody Administration.

Reactivation of bone lining cells (BLCs) is a crucial mechanism governing the anabolic action of anti-sclerostin antibody (Scl-Ab) via modeling-based bone formation; however, it remains unclear whether this reactivation can be attenuated after persistent administration of Scl-Ab. Here, we aimed to investigate the reproducibility of persistent Scl-Ab administration for the reactivation of BLCs, and to elucidate the relationship between the activity of BLCs and serum levels of N-terminal procollagen type I (P1NP) during chronic Scl-Ab administration. We conducted an osteoblast lineage tracing study. Briefly, Dmp1-CreERt2(+):Rosa26R mice were injected with 1 mg of 4-hydroxy-tamoxifen weekly from postnatal weeks four to eight. Mice were treated twice with either vehicle or Scl-Ab (25 mg/kg) at weeks 12, 16, and 20, and were euthanized at weeks 8, 12, 13, 16, 17, 20, and 21 (4-6 mice in each group). After euthanization, the number and thickness of X-gal (+) cells on the periosteum of the femoral bones and the serum levels of P1NP were quantified at each time point. Scl-Ab induced a significant increase in the thickness of X-gal (+) cells on periosteal bone surfaces at postnatal weeks 13 (after 1st dose), 17 (after 2nd dose), and 21 (after 3rd dose) compared to that in vehicle-treated mice (all P < 0.001). In the Scl-Ab group, significant increases in the thickness of labeled cells were observed between weeks 16 and 17 and weeks 20 and 21 (both P < 0.001). The percentage increase in X-gal (+) cell thickness was 108.9% from week 12 to week 13, 54.6% from week 16 to week 17, and 49.2% from week 20 to week 21 in the Scl-Ab group. Although Scl-Ab treatment increased the serum levels of P1NP at postnatal weeks 13 and 17 compared with those at week 12 (P = 0.017 and P = 0.038, respectively), the same was not observed at week 21 (P = 0.296). A significant increase in P1NP levels was observed between weeks 16 and 17 and weeks 20 and 21 in the Scl-Ab group (P = 0.005 and P = 0.007, respectively). The percentage increase in P1NP levels was 141.7% from weeks 12 to 13, 114.8% from weeks 16 to 17, and 99.4% from weeks 20 to 21. Serum P1NP levels were positively correlated with X-gal (+) cell thickness (R2 = 0.732, P < 0.001). Reactivation of BLCs is modestly attenuated, but reproducible, during persistent Scl-Ab administration. Serum P1NP levels appear to be an indicator of the impact of Scl-Ab on the conversion of BLCs into mature osteoblasts on periosteal bone surfaces, thus contributing to modeling-based bone formation.

Improved Erythrocyte Deformability Induced by Sodium-Glucose Cotransporter 2 Inhibitors in Type 2 Diabetic Patients.

PURPOSE: Sodium-glucose cotransporter 2 (SGLT-2) inhibitors are antidiabetic drugs that improve cardiovascular outcomes. Hemoglobin and hematocrit values increase after SGLT-2 inhibitor administration. Although these factors increase blood viscosity and the risk of cardiovascular disease, SGLT-2 inhibitors have protective effects on the cardiovascular system. The mechanisms for this paradoxical phenomenon remain unclear, and the effect of SGLT-2 inhibitors on hemorheology has not been studied. METHODS: We evaluated the hemorheological parameters of 63 patients of whom 38 received metformin with a dipeptidyl peptidase 4 (DPP-4) inhibitor, while 25 received metformin with SGLT-2 inhibitor. Blood viscosity was measured using a cone-and-plate viscometer, erythrocyte aggregation was measured using a modified erythrocyte sedimentation rate method, and erythrocyte membrane fluctuation was measured as deformability, using a diffraction optical tomography. RESULTS: Both blood viscosity and erythrocyte aggregation increased in the SGLT-2 inhibitor group, although erythrocyte deformability was significantly improved compared with that of the DPP-4 inhibitor group (DPP-4 inhibitor 43.71 ± 5.13 nm; SGLT-2 inhibitor 53.88 ± 4.88 nm; p < 0.001). When the two groups were compared after propensity score matching, no differences in blood viscosity at high shear rates and erythrocyte aggregation were observed, although erythrocyte deformability was significantly improved in the SGLT-2 inhibitor group (DPP-4 inhibitor 45.01 ± 5.28 nm; SGLT-2 inhibitor 53.14 ± 4.72 nm; p = 0.001). CONCLUSION: This study demonstrates that erythrocyte deformability was improved in the SGLT-2 inhibitor group compared with that in the DPP-4 inhibitor group. This improvement in erythrocyte deformability is expected to have a protective effect on the cardiovascular system.

Association of Triglyceride-Glucose Index with Bone Mineral Density in Non-diabetic Koreans: KNHANES 2008-2011.

The association of insulin resistance (IR), as indicated by the homeostasis model assessment of insulin resistance, with bone metabolism is yet to be clarified. We aimed to investigate the relationship of IR with bone mass by using the triglyceride-glucose (TyG) index as an alternative marker of IR. Data of 4810 non-diabetes individuals (2552 men aged ≥ 50 years and 2258 postmenopausal women) from the Korean National Health and Nutritional Examination Survey IV and V were analyzed. Bone mineral density (BMD) at the lumbar spine, femoral neck, total hip, and whole body were measured using dual-energy X-ray absorptiometry. After adjusting for confounding factors, there were inverse relationships of TyG index with femoral neck, total hip, and whole body BMD in men (ß = - 0.085, P < 0.001 at femoral neck; ß = - 0.046, P = 0.037 at total hip; ß = - 0.098, P < 0.001 at whole body). However, in women, femoral neck and whole body BMD were negatively associated with the TyG index (ß = - 0.071, P = 0.008 at femoral neck and ß = - 0.065, P = 0.005 at whole body). The highest TyG index tertile exhibited reduced femoral neck BMD in both sexes (P = 0.003 in men and P = 0.013 in women) and reduced whole body BMD in men (P < 0.001) after adjusting for confounders. When the study subjects were divided into BMI (body mass index) < 23 kg/m2 and ≥ 23 kg/m2 groups, the TyG index was significantly associated with femoral neck BMD only in the women with BMI < 23 kg/m2 (P = 0.009). We observed a significant association between the highest TyG index tertile and low bone mass at the femoral neck in women with BMI < 23 kg/m2 (P = 0.003) that was not observed in women with BMI ≥ 23 kg/m2 and men. In conclusion, IR evaluated using the TyG index was inversely associated with femoral neck BMD in non-diabetic men aged ≥ 50 years and postmenopausal women. The negative influence of IR on femoral neck BMD was robust in the women with BMI < 23 kg/m2. This indicates a differential effect of IR on BMD according to skeletal site, sex, and BMI.

Application of Machine Learning to Identify Clinically Meaningful Risk Group for Osteoporosis in Individuals Under the Recommended Age for Dual-Energy X-Ray Absorptiometry.

Dual-energy X-ray absorptiometry (DXA) is the gold standard for diagnosing osteoporosis; it is generally recommended in men ≥ 70 and women ≥ 65 years old. Therefore, assessment of clinical risk factors for osteoporosis is very important in individuals under the recommended age for DXA. Here, we examine the diagnostic performance of machine learning-based prediction models for osteoporosis in individuals under the recommended age for DXA examination. Data of 2210 men aged 50-69 and 1099 women aged 50-64 obtained from the Korea National Health and Nutrition Examination Survey IV-V were analyzed. Extreme gradient boosting (XGBoost) was used to find relevant clinical features and applied to three machine learning models: XGBoost, logistic regression, and a multilayer perceptron. For the prediction of osteoporosis, the XGBoost model using the top 20 features extracted from XGBoost showed the most reliable performance with area under the receiver operating characteristic curve (AUROC) of 0.73 and 0.79 in men and women, respectively. We compared the diagnostic accuracy of the Shapley additive explanation values based on a risk-score model obtained from XGBoost and conventional osteoporosis risk assessment tools for prediction of osteoporosis using optimal cut-off values for each model. We observed that a cut-off risk score of ≥ 28 in men and ≥ 47 in women was optimal to classify a positive screening for osteoporosis (an AUROC of 0.86 in men and 0.91 in women). The XGBoost-based osteoporosis-prediction model outperformed conventional risk assessment tools. Therefore, machine learning-based prediction models are a more suitable option than conventional risk assessment methods for screening osteoporosis in individuals under the recommended age for DXA examination.

A challenging TSH/GH co-secreting pituitary adenoma with concomitant thyroid cancer; a case report and literature review.

BACKGROUND: Thyroid stimulating hormone (TSH) secreting pituitary adenoma (TSHoma) with coexisting thyroid cancer is extremely rare, and proper treatment of both diseases may pose a unique clinical challenge. When TSHoma has plurihormonality, particularly involving the co-secretion of growth hormone (GH), management can be more complicated. Herein, we present a difficult-to-manage case of papillary thyroid cancer with an incurable TSH/GH-secreting pituitary adenoma. CASE PRESENTATION: A 59-year-old man was referred to our hospital due to memory impairment and inappropriate TSH level. Sella magnetic resonance imaging revealed a huge pituitary mass extending to the suprasellar area. Clinical diagnosis of TSH/GH co-secreting pituitary adenoma was made based on elevated free T4, total T3, serum α-subunit, insulin-like growth factor-1 levels and non-suppressible GH levels after oral glucose loading. Rectal cancer and multifocal papillary thyroid microcarcinoma (PTMC) were diagnosed during initial screening for internal malignancy; lower anterior resection was performed and close observation was planned for PTMC. Long-acting octreotide therapy was commenced, which resulted in a dramatic reduction in TSHoma size and facilitated control of hormonal excess. Total thyroidectomy and radioactive iodine (RAI) therapy were needed during follow up due to the growth of PTMC. After the surgery, the pituitary adenoma represented resistance to somatostatin analogue therapy and the tumor size gradually increased despite the addition of dopamine agonist therapy. Furthermore, TSH suppressive therapy with levothyroxine was impossible and an adequate TSH level for RAI therapy was unmountable. Late debulking pituitary surgery was ineffective, and the patient gradually deteriorated and lost to follow up. CONCLUSION: We report the first aggravated case of TSH/GH co-secreting pituitary tumor after total thyroidectomy for concomitant multifocal PTMC. Deferring of thyroid surgery until the TSHoma is well controlled may be the optimal therapeutic strategy in patients with TSHoma and coexistent thyroid cancer; ablative thyroid surgery may result in catastrophic pituitary tumor growth.

Surgery is a safe, effective first-line treatment modality for noninvasive prolactinomas.

PURPOSE: Dopamine agonists (DAs) have long been the recommended first-line treatment for prolactinoma. Given the remarkable developments in surgical techniques, however, surgery is on the rise. We compared the treatment outcomes of patients with noninvasive prolactinomas receiving two different initial treatments (DAs and transsphenoidal surgery). METHODS: We reviewed 745 patients with hyperprolactinemia or pituitary tumors treated from 2004 to 2020 at Chonnam National University Hwasun Hospital and identified 310 with prolactinomas. After selecting patients who had pituitary tumors with Knosp grade 0 to 1 with follow-up period over 1 year, 70 patients (29 who underwent surgery and 41 who received DAs as the initial treatment) were finally included for a comparative study. RESULTS: The surgery group exhibited better outcomes in terms of DA-free remission and the structural response, although the tumor size was significantly larger than in the DA group. The groups exhibited comparable results in terms of symptom control and the biochemical response. Univariate and multivariate analyses indicated that surgery as the initial treatment modality provided significantly better clinical outcomes in terms of DA-free remission. In the surgery group, a postoperative prolactin level < 10 ng/mL was the only significant predictor of DA-free remission. CONCLUSIONS: Transsphenoidal surgery showed comparable clinical outcomes in patients with prolactinomas, and low complication rates. The decision regarding the first-line treatment modality for non-invasive prolactinomas should be made on an individual basis.

Effect of Endogenous Parathyroid Hormone on Bone Geometry and Skeletal Microarchitecture.

Parathyroid hormone (PTH) has anabolic or catabolic effects on bones; however, the skeletal effect of endogenous PTH on cortical and trabecular bones is not yet clear. Therefore, we aimed to examine the effects of an excess and a deficiency of endogenous PTH on the lumbar spine trabecular bone score (TBS) and bone geometry using dual-energy X-ray absorptiometry. We retrospectively included 70 patients with primary hyperparathyroidism (PHPT), 26 patients with idiopathic or postoperative hypoparathyroidism (HypoPT), and 96 normal controls matched by age, sex, and body mass index. The bone mineral density (BMD) at the lumbar spine, femur neck, and total hip was higher in the HypoPT, followed by the controls and PHPT group (all P < 0.001). The TBS was significantly decreased in the PHPT group compared to the controls (P = 0.021); however, statistical significance disappeared after adjusting for the lumbar BMD (P = 0.653). There were no significant differences in the TBS between the HypoPT group and controls as well as the PHPT and HypoPT group. As for bone geometry parameters, the cross-sectional area, cross-sectional moment of inertia, and section modulus were higher in the HypoPT, followed by the controls and PHPT group (all P < 0.001); statistical significance remained after adjusting for the total hip BMD. We also observed a significantly increased cortical neck width in the HypoPT group compared to the PHPT group (P = 0.009). The buckling ratio was higher in the PHPT than the HypoPT group and controls (P = 0.018 and P = 0.013, respectively). The present study demonstrated that an excess of endogenous PTH had catabolic effects on both cortical and trabecular bones. Under conditions of endogenous PTH deficiency, the effect on cortical bone was pronounced, but that on trabecular bone was modest.

Dehydroepiandrosterone Sulfate and Free Testosterone but not Estradiol are Related to Muscle Strength and Bone Microarchitecture in Older Adults.

The study aimed to elucidate the relationship between sex steroids and muscle mass, muscle strength, and trabecular bone score (TBS) in a community-dwelling aged population. We analyzed 922 men > 60 years of age and 1244 postmenopausal women. Weak muscle strength was defined as hand grip strength < 26 kg for men and < 18 kg for women, whereas degraded bone microarchitecture was defined as a TBS ≤ 1.2. The mean age was 70.2 ± 6.8 years for men and 71.2 ± 6.7 years for women. Participants within higher dehydroepiandrosterone sulfate (DHEAS) and free testosterone (FT) tertiles were likely to be younger, have greater muscle mass, and have stronger hand grip strength. Based on logistic regression models, men within the lowest FT tertile had weaker muscle strength compared to those in the highest tertile (adjusted odds ratio [OR] 2.28; 95% confidence interval [CI] 1.33-3.91). Women within the lowest DHEAS and FT tertile had weaker muscle strength compared to those in the highest tertile (adjusted OR for DHEAS 1.42; 95% CI 1.02-1.99; adjusted OR for FT 1.77, 95% CI 1.26-2.48). Moreover, men within the lowest FT tertile exhibited degraded bone microarchitecture compared to those in the highest tertile (adjusted OR 2.57, 95% CI 1.46-4.51). However, estradiol was not related to muscle strength or bone microarchitecture in both sexes. In conclusion, in aged men, serum FT was closely associated with muscle strength and bone microarchitecture and in postmenopausal women, serum DHEAS and FT were related to muscle strength.

Metabolic characteristics of subjects with spine-femur bone mineral density discordances: the Korean National Health and Nutrition Examination Survey (KNHANES 2008-2011).

The diagnosis of osteoporosis is determined based on the lowest bone mineral density (BMD) T-score at the lumbar spine (LS) and hip. However, there are occasional marked discordances between the T-score of LS and femur neck (FN). We aimed to examine the prevalence and characteristics of individuals with spine-femur BMD discordance using a nationwide survey. A total of 3233 men aged ≥ 50 years and 2915 postmenopausal women were included from the Korean National Health and Nutrition Examination Surveys (2008-2011). The spine-femur discordance was defined as a difference of ≥ 1.5 SD between LS and FN BMD. Subjects were divided into three groups: low LS (LS < FN), low FN (LS > FN), and no discordance. Four-hundred and seventeen men (12.9%) and two hundred and ninety women (10%) exhibited spine-femur BMD discordance. The prevalence of hypertension and diabetes was higher in men and women with low FN BMD than in any other group. Fasting plasma glucose and homeostasis model assessment of insulin resistance was the highest in subjects with low FN BMD among the three groups. Low FN BMD revealed higher serum parathyroid hormone and lower 25-hydroxyvitamin D3 levels compared to any other group in women, but this was not observed in men. Osteoporosis was prevalent in subjects with discordance in both genders, particularly, in those with low LS BMD (31.6% in men and 63.5% in women). Given the high prevalence of spine-femur BMD discordance, low FN BMD may be associated with vitamin D deficiency and insulin resistance, but low LS BMD may present severe osteoporosis.

Amount of smoking, pulmonary function, and bone mineral density in middle-aged Korean men: KNHANES 2008-2011.

Smoking induces bone loss; however, data on the relationship between smoking history and bone mineral density (BMD) are lacking. Age and pulmonary function can affect BMD. We investigated the relationships among pack-years (PYs) of smoking, pulmonary function, and BMD in middle-aged Korean men (50-64 years old). This cross-sectional study used data from the Korean National Health and Nutrition Examination Survey, 2008-2011. All participants underwent BMD measurements using dual energy X-ray absorptiometry and pulmonary function tests using standardized spirometry. In total, 388 never-smokers and 1088 ever-smokers were analyzed. The number of PYs of smoking was negatively correlated with total hip BMD (r = -0.088; P = 0.004) after adjusting for age, height, and weight. Ever-smokers were classified into 3 groups according to PYs of smoking. The highest tertile (n = 482) exhibited significantly lower total hip bone mass than the lowest tertile (n = 214) after adjusting for confounding factors (age, height, weight, forced expiratory volume in 1 s (FEV1), alcohol consumption, physical activity, and vitamin D levels) that could affect bone metabolism (P = 0.003). In conclusion, smoking for >30 PYs was significantly associated with low hip BMD after adjusting for pulmonary function in middle-aged Korean men. Long-term smoking may be a risk factor for bone loss in middle-aged men independent of age, height, weight, and pulmonary function.

Extracorporeal Shock Wave Therapy Alters the Expression of Fibrosis-Related Molecules in Fibroblast Derived from Human Hypertrophic Scar.

Extracorporeal shock wave therapy (ESWT) considerably improves the appearance and symptoms of post-burn hypertrophic scars (HTS). However, the mechanism underlying the observed beneficial effects is not well understood. The objective of this study was to elucidate the mechanism underlying changes in cellular and molecular biology that is induced by ESWT of fibroblasts derived from scar tissue (HTSFs). We cultured primary dermal fibroblasts derived from human HTS and exposed these cells to 1000 impulses of 0.03, 0.1, and 0.3 mJ/mm². At 24 h and 72 h after treatment, real-time PCR and western blotting were used to detect mRNA and protein expression, respectively, and cell viability and mobility were assessed. While HTSF viability was not affected, migration was decreased by ESWT. Transforming growth factor beta 1 (TGF-ß1) expression was reduced and alpha smooth muscle actin (α-SMA), collagen-I, fibronectin, and twist-1 were reduced significantly after ESWT. Expression of E-cadherin was increased, while that of N-cadherin was reduced. Expression of inhibitor of DNA binding 1 and 2 was increased. In conclusion, suppressed epithelial-mesenchymal transition might be responsible for the anti-scarring effect of ESWT, and has potential as a therapeutic target in the management of post-burn scars.

The natural history and hip geometric changes of primary hyperparathyroidism without parathyroid surgery.

There have been few reports on changes in bone geometry in asymptomatic patients with primary hyperparathyroidism (PHPT) not treated surgically. We reviewed the records concerning biochemical parameters, bone mineral density (BMD), and hip geometry in 119 PHPT patients who did not undergo parathyroidectomy, followed up at one of three hospitals affiliated to Seoul National University from 1997 to 2013. We examined biochemical parameters over 7 years and BMD and hip geometry over 5 years of follow-up. We further compared hip geometry and BMD derived from dual-energy X-ray absorptiometry (DXA) between patients and age- and sex-matched controls. The median follow-up duration of 56 patients for whom surgery was not indicated was 33.9 months (range 11.2-131.2 months), and 19.6 % of these patients had disease progression during follow-up. Serum calcium levels remained stable for 7 years in all 119 patients. From a comparison of the PHPT patients for whom surgery was not indicated with controls, both male and postmenopausal female patients had significantly lower hip axis length (P < 0.001), cross-sectional moment of inertia (P < 0.001), cross-sectional area (P < 0.001), and section modulus (P < 0.001). In addition, cortical thickness was significantly decreased at 5 years compared with individual baseline values (P = 0.003). However, there was no significant change in BMD for the duration of the 5-year follow-up. DXA-derived geometry can detect skeletal change in asymptomatic PHPT patients for whom surgery is not indicated, supporting the concept that even mild PHPT can eventually compromise the cortical bones. Hip geometry is a potential tool for monitoring skeletal complication in asymptomatic PHPT patients.

Outcomes analysis of surgical and medical treatments for patients with primary aldosteronism.

Patients with aldosterone-producing adenomas are treated using surgery, and patients with idiopathic hyperaldosteronism receive medical treatment using mineralocorticoid receptor antagonists (MRAs). However, the outcomes of surgical and medical treatment for primary aldosteronism (PA) remain unclear. Therefore, we compared the outcomes of surgical and medical treatment for PA and aimed to identify a specific subgroup that might benefit from medical treatment. We identified 269 patients who were treated for PA (unilateral excess: 221 cases; bilateral excess: 48 cases) during 2000-2015 at the Seoul National University Hospital and two other tertiary centers. The main outcomes were the amelioration of hypertension and hypokalemia. Treatment improved hypertension in the surgical treatment group (78.2%) and the medical treatment group (55.6%) (p = 0.001). At the last follow-up, hypokalemia was normalized in the surgical treatment group (97.1%) and the medical treatment group (93.7%, p = 0.046). Among patients with unilateral aldosterone excess, surgery provided advantages in resolving hypertension without worsening renal function. Among patients who were >60 years old or had impaired renal function, surgical and medical treatment provided similar amelioration of hypokalemia and hypertension. Three patients developed hyperkalemia after surgery, and no patients developed hyperkalemia after initiating medical treatment. The surgical treatment group exhibited a lower postoperative estimated glomerular filtration rate (eGFR) and higher serum potassium levels, compared to the medical treatment group. Surgical treatment provided better hypertension and hypokalemia outcomes among patients with PA, compared to medical treatment. However, MRAs may be appropriate for elderly patients with impaired renal function.

Femoral geometry, bone mineral density, and the risk of hip fracture in premenopausal women: a case control study.

BACKGROUND: The purpose of this study was to determine the relationships among hip geometry, bone mineral density, and the risk of hip fracture in premenopausal women. METHODS: The participants in this case-control study were 16 premenopausal women with minimal-trauma hip fractures (fracture group) and 80 age-and BMI-adjusted controls. Subjects underwent dual-energy X-ray absorptiometry (DXA) to assess BMD at the proximal femur and to obtain DXA-derived hip geometry measurements. RESULTS: The fracture group had a lower mean femoral neck and total hip BMD than the control group (0.721 ± 0.123 vs. 0.899 ± 0.115, p <0.001 for the femoral neck BMD and 0.724 ± 0.120 vs. 0.923 ± 0.116, p <0.001 for the total hip BMD). In addition, participants in the fracture group had a longer hip axis length (HAL; p = 0.007), narrower neck shaft angle (NSA; p = 0.008), smaller cross sectional area (CSA; p < 0.001) and higher cross sectional moment of inertia (CSMI; p = 0.004) than those in control group. After adjusting for BMD, the fracture group still had a significantly longer mean HAL (p = 0.020) and narrower NSA (p = 0.006) than the control group. CONCLUSIONS: BMD is an important predictor of hip fracture in premenopausal women. Furthermore, HAL and NSA are BMD-independent predictors of hip fracture in premenopausal women. Hip geometry may be clinically useful for identification of premenopausal women for whom active fracture prevention should be considered.

Active Surveillance for Low-Risk Papillary Thyroid Carcinoma as an Acceptable Management Option with Additional Benefits: A Comprehensive Systematic Review.

BACKGRUOUND: Active surveillance (AS) has been introduced as a management strategy for low-risk papillary thyroid carcinoma (PTC) due to its typically indolent nature. Despite this, the widespread adoption of AS has encountered several challenges. The aim of this systematic review was to evaluate the safety of AS related to disease progression and its benefits compared with immediate surgery (IS). METHODS: Studies related to AS in patients with low-risk PTC were searched through the Ovid MEDLINE, Embase, Cochrane Library, and KoreaMed databases. Studies on disease progression, surgical complication, quality of life (QoL), and cost-effectiveness were separately analyzed and narratively synthesized. RESULTS: In the evaluation of disease progression, the proportions of cases with tumor growth ≥3 mm and a volume increase >50% were 2.2%-10.8% and 16.0%-25.5%, respectively. Newly detected lymph node metastasis was identified in 0.0%-1.4% of patients. No significant difference was found between IS and delayed surgery in surgical complications, including vocal cord paralysis and postoperative hypoparathyroidism. AS was associated with better QoL than IS. Studies on the cost-effectiveness of AS reported inconsistent data, but AS was more cost-effective when quality-adjusted life years were considered. CONCLUSION: AS is an acceptable management option for patients with low-risk PTC based on the low rate of disease progression and the absence of an increased mortality risk. AS has additional benefits, including improved QoL and greater QoL-based cost-effectiveness.

Evaluation and Management of Bone Health in Patients with Thyroid Diseases: A Position Statement of the Korean Thyroid Association.

Thyroid hormones play an important physiological role in maintaining adult bone structure and strength. Consequently, thyroid dysfunction is related to skeletal outcomes. Overt hyperthyroidism is an established cause of high bone turnover with accelerated bone loss, leading to osteoporosis and increased fracture risk. Hyperthyroidism induced by thyroid-stimulating hormone-suppressive therapy in patients with differentiated thyroid cancer is a cause of secondary osteoporosis. In contrast, there is a lack of evidence on the negative impact of hypothyroidism on bone health. Considering the clinical updates on the importance of bone health in thyroid dysfunction, the Task Force from the Clinical Practice Guidelines Development Committee of the Korean Thyroid Association recently developed a position statement on the evaluation and management of bone health of patients with thyroid diseases, particularly focused on endogenous hyperthyroidism and thyroid-stimulating hormone-suppressive therapy-associated hyperthyroidism in patients with differentiated thyroid cancer. Herein, we review the Korean Thyroid Association's position statement on the evaluation and management of bone health associated with thyroid diseases.

A Comprehensive Assessment of the Harms of Fine-Needle Aspiration Biopsy for Thyroid Nodules: A Systematic Review.

BACKGRUOUND: There have concerns related with the potential harms of fine-needle aspiration biopsy (FNAB). We aimed to summarize the clinical complications and evaluate the safety of FNAB. METHODS: Studies related with the harms of FNAB were searched on MEDLINE, Embase, Cochrane library, and KoreaMed from 2012 to 2022. Also, studies reviewed in the previous systematic reviews were evaluated. Included clinical complications were postprocedural pain, bleeding events, neurological symptoms, tracheal puncture, infections, post-FNAB thyrotoxicosis, and needle tract implantation of thyroid cancers. RESULTS: Twenty-three cohort studies were included in this review. Nine studies which were related with FNAB-related pain showed that most of the subjects had no or mild discomfort. The 0% to 6.4% of the patients had hematoma or hemorrhage after FNAB, according to 15 studies. Vasovagal reaction, vocal cord palsy, and tracheal puncture have rarely described in the included studies. Needle tract implantation of thyroid malignancies was described in three studies reporting 0.02% to 0.19% of the incidence rate. CONCLUSION: FNAB is considered to be a safe diagnostic procedure with rare complications, which are mainly minor events. Thorough assessement of the patients' medical condition when deciding to perform FNABs would be advisable to lower potential complications.

Elevated triglyceride levels are associated with increased risk for major adverse cardiovascular events in statin-naïve rheumatoid arthritis patients: A nationwide cohort study.

OBJECTIVES: To investigate the association between the four components of the lipid profile (total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C)) at baseline and composite major adverse cardiovascular events (MACEs) in statin-naïve rheumatoid arthritis (RA) patients with no previous history of cardiovascular events. METHODS: This nationwide population-based cohort study was performed on a total of 15,216 statin-naïve RA patients. The end point was a composite of clinical events, including myocardial infarction (MI), stroke, coronary revascularization, and cardiovascular death. We compared the incidence of and risk for clinical events according to each lipid variable. RESULTS: During follow-up (median 4.70 years), the incidence of MACE per 1000 person-years was 7.27. Among the four lipid components, only higher baseline TG levels were significantly associated with increased risk for composite MACE in RA subjects. The risk for composite MACE was significantly higher in the third (adjusted hazard ratio (HR), 1.35 [95% confidence interval (CI), 1.03-1.78]) and highest quartiles (adjusted HR, 1.74 [95%CI, 1.33-2.28]) of baseline TG level versus the lowest quartile. CONCLUSIONS: In statin-naïve RA patients, increased TG level is associated with increased risk for MACE. Therefore, screening and intervention for increased TG level may be clinically beneficial in this population.

Fracture Liaison Service in Korea: 2022 Position Statement of the Korean Society for Bone and Mineral Research.

Osteoporosis and osteoporotic fractures cause socioeconomic concerns, and medical system and policies appear insufficient to prepare for these issues in Korea, where the older adult population is rapidly increasing. Many countries around the world are already responding to osteoporosis and osteoporotic fractures by adopting fracture liaison service (FLS), and such an attempt has only begun in Korea. In this article, we introduce the operation methods for institutions implementing FLS and characteristics of services, and activities of the FLS Committee for FLS implementation in the Korean Society for Bone and Mineral Research. In addition, we hope that the current position statement will contribute to the implementation of FLS in Korea and impel policy changes to enable a multidisciplinary and integrated FLS operated under the medical system.

Early Thyroid Volume Reduction in Subacute Thyroiditis Can be a Potential Indicator for Hypothyroidism.

Background: Thyroid volume has been reported to decrease significantly after episodes of subacute thyroiditis (SAT); however, the relationship between thyroid volume and hypothyroidism remains unclear. This study assessed the association between thyroid volume changes and the hypothyroid phase in patients with SAT, a condition that can progress to persistent hypothyroidism. Methods: This retrospective study evaluated 37 patients diagnosed with SAT at the Department of Endocrinology and Metabolism of Chonnam National University Hwasun Hospital (CNUHH) between 2016 and 2021. Since we could not determine the clinical characteristics of patients with SAT before their episodes, 120 healthy individuals who underwent thyroid ultrasonography during regular check-ups from 2019 to 2021 at CNUHH were selected for comparison. Subgroup analyses were performed on patients with SAT with and without the hypothyroid phase during their clinical course. Results: Thyroid volume was significantly greater in SAT patients at the first visit than in controls (p<0.05), and it decreased constantly throughout the follow-up period. Subgroup analysis showed that the initial thyroid volumes were similar in patients with SAT with and without the hypothyroid phase. However, SAT patients with the hypothyroid phase had significantly smaller thyroid volumes at the 1 month (p=0.025) and 3 month (p=0.006) follow-up visits. The reduction rate of the thyroid volume was significantly different within the first month (p=0.009). Conclusion: A greater reduction in thyroid volume in SAT patients within 1 month of episode had a higher chance of developing a subsequent hypothyroid phase, which can lead to persistent hypothyroidism. Serial thyroid ultrasonography in patients with SAT, especially within the first month, may help in predicting the disease course of SAT.