The Association of Smoking Status with Diabetic Microvascular Complications in Korean Patients with Type 2 Diabetes.

PURPOSE: Few studies have investigated the association between smoking and microvascular complications in the Asian population with type 2 diabetes mellitus (T2DM). We aimed to investigate the relationship between smoking status and microvascular complications in Korean patients with T2DM. MATERIALS AND METHODS: From the Korean National Diabetes Program cohort, we included 2316 Korean male with T2DM who had baseline clinical information available, including their smoking status, and underwent diabetic complication studies. RESULTS: Compared to non-smokers, current smokers had higher odds of any-microvascular complications [adjusted odds ratio (aOR) 1.45, 95% confidence interval (CI) 1.07-1.97, p=0.016]. The odds of neuropathy were significantly higher; however, the odds of retinopathy were significantly lower in current smokers than in nonsmokers (all p<0.05). Among those who underwent repeated complication tests after 3 years, the risk of newly developed retinopathy was significantly increased in ex-smokers [aOR 3.77 (95% CI 1.61-8.87), p=0.002]. Within ex-smokers, long smoking duration and smoking cessation within the recent 5 years were associated with an increased risk of newly developed retinopathy (all p<0.05). CONCLUSION: Male smokers had higher odds of having overall diabetic microvascular complications, including neuropathy. However, the odds of having retinopathy were significantly lower among current smokers. More attention and research are needed regarding the increased risk of retinopathy development in ex-smokers who have recently stopped smoking after a long history of smoking.

On-Chip Annealing Using Embedded Micro-Heater for Highly Sensitive and Selective Gas Detection.

The demand for gas sensing systems that enable fast and precise gas recognition is growing rapidly. However, substantial challenges arise from the complex fabrication process of sensor arrays, time-consuming data transmission to an external processor, and high energy consumption in multi-stage data processing. In this study, a gas sensing system using on-chip annealing for fast and power-efficient gas detection is proposed. By utilizing a micro-heater embedded in the gas sensor, the sensing material of adjacent sensors in the same substrate can be easily varied without further fabrication steps. The response to oxidizing gas is constrained in metal oxide (MOX) sensing material with small grain sizes, as the depletion width of grain cannot extend beyond the grain size during the gas reaction. On the other hand, the response to reducing gases and humidity, which decrease the depletion width, is less affected by grain sizes. A readout circuit integrating a differential amplifier and dual FET-type gas sensors effectively emphasizes the response to oxidizing gases by canceling the response to reducing gases and humidity. The selective on-chip annealing method is applicable to various MOX sensing materials, demonstrating its potential for application in commercial fields due to its simplicity and expandability.

Reconfigurable Manipulation of Oxygen Content on Metal Oxide Surfaces and Applications to Gas Sensing.

Oxygen vacancies and adsorbed oxygen species on metal oxide surfaces play important roles in various fields. However, existing methods for manipulating surface oxygen require severe settings and are ineffective for repetitive manipulation. We present a method to manipulate the amount of surface oxygen by modifying the oxygen adsorption energy by electrically controlling the electron concentration of the metal oxide. The surface oxygen control ability of the method is verified using first-principles calculations based on density functional theory (DFT), X-ray photoelectron spectroscopy (XPS), and electrical resistance analysis. The presented method is implemented by fabricating oxide thin film transistors with embedded microheaters. The method can reconfigure the oxygen vacancies on the In2O3, SnO2, and IGZO surfaces so that specific chemisorption dominates. The method can selectively increase oxidizing (e.g., NO and NO) and reducing gas (e.g., H2S, NH3, and CO) reactions by electrically controlling the metal oxide surface to be oxygen vacancy-rich or adsorbed oxygen species-rich. The proposed method is applied to gas sensors and overcomes their existing limitations. The method makes the sensor insensitive to one gas (e.g., H2S) in mixed-gas environments (e.g., NO2+H2S) and provides a linear response (R2 = 0.998) to the target gas (e.g., NO2) concentration within 3 s. We believe that the proposed method is applicable to applications utilizing metal oxide surfaces.

Risk of Fractures in Thyroid Cancer Patients With Postoperative Hypoparathyroidism: A Nationwide Cohort Study in Korea.

Postoperative hypoparathyroidism (PO-hypoPT) is an uncommon complication of total thyroidectomy in thyroid cancer patients. Although long-term hypoPT causes characteristic changes in bone metabolism, the risk of fractures in hypoPT remains inconclusive. We investigated the risk of fractures in Korean thyroid cancer patients with PO-hypoPT. This was a retrospective cohort study using data from the Korea Central Cancer Registry and Korean National Health Insurance Service. We analyzed 115,821 thyroid cancer patients aged ≥18 years, who underwent total thyroidectomy between 2008 and 2016. The risk of any fractures, including vertebral, hip, humerus, and wrist fractures, according to parathyroid function after total thyroidectomy, was analyzed using the multivariable Cox proportional hazard model. The PO-hypoPT and preserved parathyroid function groups included 8789 (7.6%) and 107,032 (92.4%) patients, respectively. Over a mean follow-up duration of 4.8 years, 159 (1.8%) and 2390 (2.2%) fractures occurred in the PO-hypoPT and preserved parathyroid function groups, respectively. The risk of any fractures was significantly lower in the PO-hypoPT group than in the preserved parathyroid function group (hazard ratio [HR] = 0.83; 95% confidence interval [CI] 0.70-0.98; p = 0.037) after adjusting for confounders. Regarding the fracture site, only the risk of vertebral fractures was significantly lower in the PO-hypoPT group compared with the preserved parathyroid function group (HR = 0.67; 95% CI 0.47-0.96; p = 0.028) after adjusting for confounders. Subgroup analyses showed that bone mineral density measurements and calcium supplementation interacted with the relationship between PO-hypoPT and the risk of any fractures (p for interactions = 0.010 and 0.017, respectively). PO-hypoPT was associated with a lower risk of fractures in thyroid cancer patients, especially at the vertebra. The relatively low bone turnover caused by PO-hypoPT and appropriate management for PO-hypoPT with active vitamin D and calcium may prevent the deterioration of skeletal health in thyroid cancer patients who can easily be exposed to long-term overtreatment with levothyroxine. © 2023 American Society for Bone and Mineral Research (ASBMR).

Transducer-Aware Hydroxy-Rich-Surface Indium Oxide Gas Sensor for Low-Power and High-Sensitivity NO2 Gas Sensing.

Low-power metal oxide (MOX)-based gas sensors are widely applied in edge devices. To reduce power consumption, nanostructured MOX-based sensors that detect gas at low temperatures have been reported. However, the fabrication process of these sensors is difficult for mass production, and these sensors are lack uniformity and reliability. On the other hand, MOX film-based gas sensors have been commercialized but operate at high temperatures and exhibit low sensitivity. Herein, commercially advantageous highly sensitive, film-based indium oxide sensors operating at low temperatures are reported. Ar and O2 gases are simultaneously injected during the sputtering process to form a hydroxy-rich-surface In2O3 film. Conventional indium oxide (In2O3) films (A0) and hydroxy-rich indium oxide films (A1) are compared using several analytical techniques. A1 exhibits a work function of 4.92 eV, larger than that of A0 (4.42 eV). A1 exhibits a Debye length 3.7 times longer than that of A0. A1 is advantageous for gas sensing when using field effect transistors (FETs) and resistors as transducers. Because of the hydroxy groups present on the surface of A1, A1 can react with NO2 gas at a lower temperature (∼100 °C) than A0 (180 °C). Operando diffuse reflectance infrared Fourier transform spectrometry (DRIFTS) shows that NO2 gas is adsorbed to A1 as nitrite (NO2-) at 100 °C and nitrite and nitrate (NO3-) at 200 °C. After NO2 is adsorbed as nitrate, the sensitivity of the A1 sensor decreases and its low-temperature operability is compromised. On the other hand, when NO2 is adsorbed only as nitrite, the performance of the sensor is maintained. The reliable hydroxy-rich FET-type gas sensor shows the best performance compared to that of the existing film-based NO2 gas sensors, with a 2460% response to 500 ppb NO2 gas at a power consumption of 1.03 mW.

Recovery of off-state stress-induced damage in FET-type gas sensor using self-curing method.

The need for high-performance gas sensors is driven by concerns over indoor and outdoor air quality, and industrial gas leaks. Due to their structural diversity, vast surface area, and geometric tunability, metal oxides show significant potential for the development of gas sensing systems. Despite the fact that several previous reports have successfully acquired a suitable response to various types of target gases, it remains difficult to maintain the reliability of metal oxide-based gas sensors. In particular, the degradation of the sensor platform under repetitive operation, such as off-state stress (OSS) causes significant reliability issues. We investigate the impact of OSS on the gas sensing performances, including response, low-frequency noise, and signal-to-noise ratio of horizontal floating-gate field-effect-transistor (FET)-type gas sensors. The 1/f noise is increased after the OSS is applied to the sensor because the gate oxide is damaged by hot holes. Therefore, the SNR of the sensor is degraded by the OSS. We applied a self-curing method based on a PN-junction forward current at the body-drain junction to repair the damaged gate oxide and improve the reliability of the sensor. It has been demonstrated that the SNR degradation caused by the OSS can be successfully recovered by the self-curing method.

In-Memory-Computed Low-Frequency Noise Spectroscopy for Selective Gas Detection Using a Reducible Metal Oxide.

Concerns about indoor and outdoor air quality, industrial gas leaks, and medical diagnostics are driving the demand for high-performance gas sensors. Owing to their structural variety and large surface area, reducible metal oxides hold great promise for constructing a gas-sensing system. While many earlier reports have successfully obtained a sufficient response to various types of target gases, the selective detection of target gases remains challenging. In this work, a novel method, low-frequency noise (LFN) spectroscopy is presented, to achieve selective detection using a single FET-type gas sensor. The LFN of the sensor is accurately modeled by considering the charge fluctuation in both the sensing material and the FET channel. Exposure to different target gases produces distinct corner frequencies of the power spectral density that can be used to achieve selective detection. In addition, a 3D vertical-NAND flash array is used with the fast Fourier transform method via in-memory-computing, significantly improving the area and power efficiency rate. The proposed system provides a novel and efficient method capable of selectively detecting a target gas using in-memory-computed LFN spectroscopy and thus paving the way for the further development in gas sensing systems.

Highly Selective and Low-Power Carbon Monoxide Gas Sensor Based on the Chain Reaction of Oxygen and Carbon Monoxide to WO3.

Carbon monoxide (CO) poisoning can easily occur in industrial and domestic settings, causing headaches, loss of consciousness, or death from overexposure. Commercially available CO gas sensors consume high power (typically 38 mW), whereas low-power gas sensors using nanostructured materials with catalysts lack reliability and uniformity. A low-power (1.8 mW @ 392 °C), sensitive, selective, reliable, and practical CO gas sensor is presented. The sensor adopts floated WO3 film as a sensing material to utilize the unique reaction of lattice oxide of WO3 with CO gas. The sensor locally modulates the electron concentration in the WO3 film, allowing O2 and CO gases to react primarily in different sensing areas. Electrons generated by the CO gas reaction can be consumed for O2 gas adsorption in a remote area, and this promotes the additional reaction of CO gas, boosting sensitivity and selectivity. The proposed sensor exhibits a 39.5 times higher response than the conventional resistor-type gas sensor fabricated on the same wafer. As a proof of concept, sensors with In2O3 film are fabricated, and the proposed sensor platform shows no advantage in detecting CO gas. Fabrication of the proposed sensor is reproducible and inexpensive due to conventional silicon-based processes, making it attractive for practical applications.

Synergistic improvement of sensing performance in ferroelectric transistor gas sensors using remnant polarization.

Gaseous pollutants, including nitrogen oxides, pose a severe threat to ecosystems and human health; therefore, developing reliable gas-sensing systems to detect them is becoming increasingly important. Among the various options, metal-oxide-based gas sensors have attracted attention due to their capability for real-time monitoring and large response. In particular, in the field of materials science, there has been extensive research into controlling the morphological properties of metal oxides. However, these approaches have limitations in terms of controlling the response, sensitivity, and selectivity after the sensing material is deposited. In this study, we propose a novel method to improve the gas-sensing performance by utilizing the remnant polarization of ferroelectric thin-film transistor (FeTFT) gas sensors. The proposed FeTFT gas sensor has IGZO and HZO as the conducting channel and ferroelectric layer, respectively. It is demonstrated that the response and sensitivity of FeTFT gas sensors can be modulated by engineering the polarization of the ferroelectric layer. The amount of reaction sites in IGZO, including electrons and oxygen vacancy-induced negatively charged oxygen, is changed depending on upward and downward polarization. The results of this study provide an essential foundation for further development of gas sensors with tunable sensing properties.

Relationships Between Pulmonary Function and Composite Indices of Femoral Neck Strength in Korean Men (KNHANES IV).

BACKGROUND: Despite the close relationship between osteoporosis and chronic pulmonary diseases, few studies have evaluated relationships between pulmonary functions and bone quality. We investigated associations between pulmonary function test results and femoral neck strength indices (SIs) in Korean men. METHODS: This population-based, cross-sectional study was conducted using data from the Korea National Health and Nutrition Examination Survey IV on 936 men aged ≥ 19 years. Pulmonary functions (forced vital capacity [FVC] and forced expiratory volume in one second [FEV1]) were measured using a dry rolling seal spirometer. Femoral neck SIs, relative to load, were calculated by hip dual-energy X-ray absorptiometry for compression strength index (CSI), bending strength index (BSI), and impact strength index (ISI). RESULTS: The 443 (47.3%) of the 936 men were current smokers. FVC, FVC percentage with respect to the expected normal value, FEV1, and FEV1 percentage with respect to the expected normal value (FEV1p) were positively associated with CSI and BSI after adjusting for confounders, including smoking history (ß = 0.003-0.223, P = 0.005-0.036). FEV1 and FEV1p were positively associated with ISI (ß = 0.000-0.014, P = 0.010-0.025). Of components of femoral neck SIs, bone mineral density was correlated with FEV1 and FEV1p (ß = 0.001-0.037, P = 0.017-0.019). After adjusting for all confounders, all femoral neck SIs increased with FVC quintiles (P for trends = 0.001-0.012), and CSI and BSI increased with FEV1 quintiles (P for trends = 0.034-0.043). CONCLUSION: Reduced pulmonary function was correlated with reduced femoral neck strength, even after adjusting for smoking history in Korean men. Femoral neck SIs might be useful tools for evaluating bone health in men with reduced pulmonary function.

Effect of charge storage engineering on the NO2 gas sensing properties of a WO3 FET-type gas sensor with a horizontal floating-gate.

In this paper, we investigate the effects of charge storage engineering (CSE) on the NO2 gas sensing properties such as response, recovery, and sensitivity of a FET-type gas sensor with a horizontal floating-gate (FG) having tungsten trioxide (WO3) as a sensing layer. When the FET transducer is set at an erase state (ΔVth = -2 V), the holes injected into the FG by Fowler-Nordheim (F-N) tunneling increase the electron concentration at the WO3-passivation layer interface. Accordingly, an oxidizing gas, NO2, can take more electrons from WO3, which increases the change in the FG voltage (ΔVFG) by a factor of 2.4. Also, the recovery speed of the sensor in the erase state can be improved by applying pre-bias (Vpre) which is larger than the read bias (Vread). As the carriers in the WO3 film that can interact with NO2 increase by the excess holes stored in the FG by the erase operation, the sensitivity of the sensor also increases 3.2 times. The effects of CSE on various sensing performances are explained using energy band diagrams.

Discrimination of Lycium chinense and L. barbarum Based on Metabolite Analysis and Hepatoprotective Activity.

Lycii Fructus is a traditional medicine used to prevent liver and kidney diseases, which commonly derives from Lycium chinense and Lycium barbarum. Here, the extracts and ethyl acetate-soluble fractions of L. chinense fruits exhibited better hepatoprotective effects than those of L. barbarum, which was likely due to differences in their composition. Therefore, GC-MS and HPLC analyses were conducted to characterize the metabolite differences between L. chinense and L. barbarum. Based on amino acid (AA) and phenolic acid (PA) profiling, 24 AAs and 9 PAs were identified in the two species. Moreover, each species exhibited unique and readily distinguishable AA and PA star graphic patterns. HPLC analysis elucidated composition differences between the ethyl acetate-soluble layers of the two compounds. Further, NMR analysis identified their chemical structures as 4-(2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl)butanoic acid and p-coumaric acid. The higher content of 4-(2-formyl-5-(hydroxymethyl)-1H-pyrrol-1-yl)butanoic acid was detected in L. chinense, whereas the content of p-coumaric acid was higher in L. barbarum. Therefore, the differences in the relative contents of these two secondary metabolites in the ethyl acetate-soluble layer of Lycii Fructus could be a good marker to discriminate between L. chinense and L. barbarum.

Proposition of deposition and bias conditions for optimal signal-to-noise-ratio in resistor- and FET-type gas sensors.

In the field of gas sensor studies, most researchers are focusing on improving the response of the sensors to detect a low concentration of gas. However, factors that make a large response, such as abundant or strong adsorption sites, also work as a source of noise, resulting in a trade-off between response and noise. Thus, the response alone cannot fully evaluate the performance of sensors, and the signal-to-noise-ratio (SNR) should additionally be considered to design gas sensors with optimal performance. In this regard, thin-film-type sensing materials are good candidates thanks to their moderate response and noise level. In this paper, we investigate the effects of radio frequency (RF) sputtering power for deposition of sensing materials on the SNR of resistor- and field-effect transistor (FET)-type gas sensors fabricated on the same Si wafer. In the case of resistor-type gas sensors, the deposition conditions that improve the response also worsen the noise either by increasing the scattering at the bulk or damaging the interface of the sensing material. Among resistor-type gas sensors with sensing materials deposited with different RF powers, a sensor with low noise shows the largest SNR despite its small response. However, the noise of FET-type gas sensors is not affected by changes in RF power and thus there is no trade-off between response and noise. The results reveal different noise sources depending on the deposition conditions of the sensing material, and provide design guidelines for resistor- and FET-type gas sensors considering noise for optimal performance.

Assessment of patient-reported outcomes (PROs): treatment satisfaction, medication adherence, and quality of life (QoL) and the associated factors in postmenopausal osteoporosis (PMO) patients in Korea.

Patient-reported outcomes (PROs) provide practical guides for treatment; however, studies that have evaluated PROs of women in Korea with postmenopausal osteoporosis (PMO) are lacking. This cross-sectional, multi-center (29 nationwide hospitals) study, performed from March 2013 to July 2014, aimed to assess PROs related to treatment satisfaction, medication adherence, and quality of life (QoL) in Korean PMO women using osteoporosis medication for prevention/treatment. Patient demographics, clinical characteristics, treatment patterns, PROs, and experience using medication were collected. The 14-item Treatment Satisfaction Questionnaire for Medication (TSQM) (score-range, 0-100; domains: effectiveness, side effects, convenience, global satisfaction), Osteoporosis-Specific Morisky Medication Adherence Scale (OS-MMAS) (score-range, 0-8), and EuroQol-5 dimensions questionnaire (index score range, - 0.22 to 1.0; EuroQol visual analog scale score range, 0-100) were used. To investigate factors associated with PROs, linear (treatment satisfaction/QoL) or logistic (medication adherence) regression analyses were conducted. A total of 1804 patients (age, 62 years) were investigated; 60.1% used bisphosphonate, with the majority (67.2%) using weekly medication, 27.8% used daily hormone replacement therapy, and 12.1% used daily selective estrogen receptor modulator. Several patients reported gastrointestinal (GI) events (31.6%) and dental visits due to problems (24.1%) while using medication. Factors associated with the highest OS-MMAS domain scores were convenience and global satisfaction. GI events were associated with non-adherence. TSQM scores for effectiveness, side effects, and GI risk factors were significantly associated with QoL. Our study elaborately assessed the factors associated with PROs of Korean PMO women. Based on our findings, appropriate treatment-related adjustments such as frequency/choice of medications and GI risk management may improve PROs.

Observation of physisorption in a high-performance FET-type oxygen gas sensor operating at room temperature.

Oxygen (O2) sensors are needed for monitoring environment and human health. O2 sensing at low temperature is required, but studies are lacking. Here we report, for the first time, that the performance of a field effect transistor (FET)-type O2 sensor operating at 25 °C was improved greatly by a physisorption sensing mechanism. The sensing material was platinum-doped indium oxide (Pt-In2O3) nanoparticles formed by an inkjet printer. The FET-type sensor showed excellent repeatability under a physisorption mechanism and showed much better sensing performance than a resistor-type sensor fabricated on the same wafer at 25 °C. The sensitivity of the sensor increased with increasing Pt concentration up to ∼10% and decreased with further increasing Pt concentration. When the sensing temperature reached 140 °C, the sensing mechanism of the sensor changed from physisorption to chemisorption. Interestingly, the pulse pre-bias before the read bias affected chemisorption but had no effect on physisorption.

Characteristics of Adrenal Incidentalomas in a Large, Prospective Computed Tomography-Based Multicenter Study: The COAR Study in Korea.

PURPOSE: Previous studies on adrenal incidentalomas (AIs) are limited by their retrospective design, small numbers of patients, Western populations, or use of an outdated imaging technique. We investigated the characteristics of AIs in Korean patients and compared them with those reported in the largest retrospective study in Italy to discover the effects of improved imaging techniques and ethnicity differences. MATERIALS AND METHODS: This was a prospective, multicenter, cross-sectional observational study including 1005 Korean patients. Levels of plasma adrenocorticotrophic hormone, 24-h urinary free cortisol (UFC), serum cortisol after a 1 mg-dexamethasone suppression test, 24-h urinary fractionated metanephrine, and plasma aldosterone and plasma renin activity were measured. All AIs were characterized using computed tomography (CT). RESULTS: Compared with the results of the Italian study, AIs in Korean patients were observed more frequently in men and predominantly on the left side. Korean patients with AIs were slightly younger, and fewer patients underwent surgery. Most AIs were nonfunctional in both studies, while fewer subclinical hypercortisolism and more primary aldosteronism (PA) cases were detected in Korean patients. In our study, high UFC levels showed very low sensitivity, compared to those in the Italian study. In pheochromocytoma or PA cases, there were no hormonal differences between the studies. AIs in Korean patients were smaller, such that a lower cutoff size for detecting adrenocortical carcinoma (ACC) could be warranted. CONCLUSION: Recent advances in CT technology were leveraged to provide accurate characteristics of AIs and to detect smaller ACCs.

The Effect on Bone Outcomes of Adding Exercise to Supplements for Osteopenic Breast Cancer Survivors: A Pilot Randomized Controlled Trial.

BACKGROUND: Cancer treatment-induced bone loss is an important long-term effect in breast cancer survivors, but evidence regarding lifestyle interventions for preventing cancer treatment-induced bone loss is lacking. OBJECTIVE: The aim of this study was to investigate the feasibility, safety, and effects of a 6-month combined home-based exercise and calcium and vitamin D supplements (EX + SUPP) intervention compared with calcium and vitamin D supplements alone (SUPP) on bone health of osteopenic breast cancer survivors. METHODS: In this pilot randomized controlled trial, we enrolled 43 women with breast cancer who were diagnosed as osteopenic through bone mineral density screening. Women were randomly assigned to the EX + SUPP group (n = 23) or the SUPP group (n = 20). RESULTS: The rates of participant retention (90.7%) and of counseling calls delivered to the EX + SUPP group (90.3%) were high. The average exercise adherence rate was 69.5% for weight-bearing exercise and 48.5% for resistance exercise. The EX + SUPP group reported no injuries or adverse events. Despite positive findings of adherence and safety, no significant group differences were observed for bone mineral density, bone turnover marker, or physical performance. CONCLUSIONS: A home-based exercise program for bone health among osteopenic breast cancer survivors is feasible and safe. There was no significant additive effect of exercise on bone outcomes under the conditions studied, however, suggesting the need for a larger trial. IMPLICATIONS FOR PRACTICE: Effective exercise intervention may require more intensive components such as higher loading forces and longer duration for improving bone health among this population.

Change of Bone Mineral Density and Biochemical Markers of Bone Turnover in Patients on Suppressive Levothyroxine Therapy for Differentiated Thyroid Carcinoma.

Untreated hyperthyroidism and high-dose thyroid hormone are associated with osteoporosis, and increased bone mineral density (BMD) has been demonstrated in postmenopausal females with hypoparathyroidism. Studies on the effect of suppressive levothyroxine (LT4) therapy on BMD and bone metabolism after total thyroidectomy in patients with differentiated thyroid carcinoma have presented conflicting results, and few studies in relation to the status of hypoparathyroidism have been studied. One hundred postmenopausal women and 24 premenopausal women on LT4 suppression therapy were included in this study. BMD of lumbar spine and femur and bone turnover markers were measured at the baseline and during the follow-up period up to 18 months using dual energy X-ray absorptiometry. Biochemical marker of bone resorption was measured by urine deoxypyridinoline and bone formation by serum osteocalcin. The age ranged from 36 to 64 years old. Thyroid stimulating hormone (TSH) was suppressed during the study. The results showed that BMD of femur and lumbar spine were not significantly changed in both pre- and postmenopausal women except femur neck in postmenopausal women without hypoparathyroidism. Patients with hypoparathyroidism had higher BMD gain than those without hypoparathyroidism in total hip (1.25 vs. -1.18%, P=0.015). Biochemical markers of bone turnover, serum osteocalcin, and urine deoxypyridinoline did not show significant change. In conclusion, patients with well differentiated thyroid carcinoma are not at a great risk of bone loss after LT4 suppressive therapy. The state of hypoparathyroidism is associated with increased BMD, particularly in postmenopausal women.