Objectives: This study examined whether the polygenic risk score (PRS) calculated from the most recent genome-wide association study for bipolar disorder (BD) of European ancestry patients is significantly associated with BD diagnosis in the Korean population. Methods: The study included 417 Korean patients with BD and 497 healthy controls. Genotyping was performed using the Korean Biobank Array. Summary statistics of the European samples from the Psychiatric Genomic Consortium were used as base data to generate the PRS for each individual. The program PRSice-2 was used to calculate the PRS. Logistic regression was conducted to determine the association between BD diagnosis and PRS for BD after adjusting for age and sex. Results: PRS for BD was significantly higher in patients diagnosed with BD compared to healthy controls. The PRS at the p-value threshold of 0.01 best explained the variance of BD after adjusting for age and sex (R2 =0.0061, p=0.039). Subgroup analyses were performed for bipolar I and II subgroups. In bipolar I patients, the PRS at the p-value threshold of 0.01 best explained the diagnosis (R2 =0.0165, p=0.0055), whereas no significant result was found for bipolar II patients. Conclusion PRS for BD calculated for the Korean sample showed a significant association with the BD diagnosis. This result suggests an overlapping genetic risk for BD between the European and Korean populations.

Objectives: This study examined whether the polygenic risk score (PRS) calculated from the most recent genome-wide association study for bipolar disorder (BD) of European ancestry patients is significantly associated with BD diagnosis in the Korean population. Methods: The study included 417 Korean patients with BD and 497 healthy controls. Genotyping was performed using the Korean Biobank Array. Summary statistics of the European samples from the Psychiatric Genomic Consortium were used as base data to generate the PRS for each individual. The program PRSice-2 was used to calculate the PRS. Logistic regression was conducted to determine the association between BD diagnosis and PRS for BD after adjusting for age and sex. Results: PRS for BD was significantly higher in patients diagnosed with BD compared to healthy controls. The PRS at the p-value threshold of 0.01 best explained the variance of BD after adjusting for age and sex (R2 =0.0061, p=0.039). Subgroup analyses were performed for bipolar I and II subgroups. In bipolar I patients, the PRS at the p-value threshold of 0.01 best explained the diagnosis (R2 =0.0165, p=0.0055), whereas no significant result was found for bipolar II patients. Conclusion PRS for BD calculated for the Korean sample showed a significant association with the BD diagnosis. This result suggests an overlapping genetic risk for BD between the European and Korean populations.

Background: In South Korea, women aged 66 years are eligible for complimentary bone mineral density (BMD) screening via the National Screening Program for Transitional Ages. We aimed to evaluate the 10-year fracture risk in women receiving BMD screening between January 2008 and December 2015. Methods: BMD was classified as normal (T-score ≥–1.0 standard deviation [SD]), osteopenia (T-score <–1.0 SD and >–2.5 SD), and osteoporosis (T score ≤–2.5 SD) from dual-energy X-ray absorptiometry. Follow-up continued from the screening date until a diagnosis for clinical fragility fracture (including sites of the vertebrae, hip, pelvis, clavicle, humerus, forearm, wrist, lower leg, and ankle), censored at the earliest date of trauma, death, or December 2017; fracture was ascertained using diagnostic codes from the National Health Insurance Service database. A multivariable Cox proportional hazard model was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of fracture in women with osteopenia or osteoporosis relative to women with normal BMD. Results: Among the 271,197 women screened, 44.0% had osteopenia and 35.2% had osteoporosis. The 10 year cumulative incidence of fragility fractures was 31.1%, 37.5%, and 44.3% in women with normal BMD, osteopenia, and osteoporosis, respectively. Fracture risk was higher in women with osteopenia (HR, 1.31; 95% CI, 1.28 to 1.34) and osteoporosis (HR, 1.68; 95% CI, 1.64 to 1.72) than in women with normal BMD. Conclusion Women with osteopenia and women with osteoporosis, identified by the national BMD screening program, demonstrated a substantially elevated risk of fracture.

PURPOSE: Few studies investigated roles of body mass index (BMI) on gastric cancer (GC) risk according to Helicobacter pylori infection status. This study was conducted to evaluate associations between BMI and GC risk with consideration of H. pylori infection information. MATERIALS AND METHODS: We performed a case-cohort study (n=2,458) that consists of a subcohort, (n=2,193 including 67 GC incident cases) randomly selected from the Korean Multicenter Cancer Cohort (KMCC) and 265 incident GC cases outside of the subcohort. H. pylori infection was assessed using an immunoblot assay. GC risk according to BMI was evaluated by calculating hazard ratios (HRs) and their 95% confidence intervals (95% CIs) using weighted Cox hazard regression model. RESULTS: Increased GC risk in lower BMI group (< 23 kg/m²) with marginal significance, (HR, 1.32; 95% CI, 0.98 to 1.77) compared to the reference group (BMI of 23-24.9 kg/m²) was observed. In the H. pylori non-infection, both lower (< 23 kg/m²) and higher BMI (≥ 25 kg/m²) showed non-significantly increased GC risk (HR, 10.82; 95% CI, 1.25 to 93.60 and HR, 11.33; 95% CI, 1.13 to 113.66, respectively). However, these U-shaped associations between BMI and GC risk were not observed in the group who had ever been infected by H. pylori. CONCLUSION: This study suggests the U-shaped associations between BMI and GC risk, especially in subjects who had never been infected by H. pylori.
Body Mass Index ; Cohort Studies ; Helicobacter pylori ; Helicobacter ; Stomach Neoplasms

PURPOSE: The association between tobacco smoking and thyroid cancer remains uncertain. We evaluated the associations of active and passive smokingwith the risk of papillary thyroid cancer (PTC), the most common type of thyroid cancer, and with the BRAF(V600E) mutation, the most common oncogenic mutation in PTC related to poor prognosis. MATERIALS AND METHODS: We conducted this study with newly diagnosed PTC patients (n=2,142) and community controls (n=21,420) individually matched to cases for age and sex. Information on active and passive smoking and potential confounders were obtained from structured questionnaires, anthropometric measurements, and medical records. BRAF(V600E) mutation status was assessed in PTC patients. We evaluated the associations of active and passive smoking with PTC and BRAF(V600E) mutation risk using conditional and unconditional logistic regression models, respectively. RESULTS: We did not find associations between exposure indices of active and passive smoking and PTC risk in both men and women, except for the association between current smoking and lower PTC risk. Cumulative smoking ≥ 20 pack-years was associated with lower BRAF(V600E) mutation risk in male PTC patients (odds ratio [OR], 0.55; 95% confidence interval [CI], 0.30 to 1.00). The CI for the association was wider in female PTC patients (OR, 0.23; 95% CI, 0.02 to 2.62), possibly owing to a smaller sample size in this stratum. CONCLUSION: We did not find consistent associations between active and passive smoking and PTC risk. Cumulative smoking ≥ 20 pack-years was associated with lower BRAF(V600E) mutation risk in male PTC patients.
Case-Control Studies ; Female ; Humans ; Logistic Models ; Male ; Medical Records ; Prognosis ; Sample Size ; Smoke ; Smoking ; Thyroid Gland ; Thyroid Neoplasms ; Tobacco Smoke Pollution

BACKGROUND: The ongoing Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) aims to observe the natural course of papillary thyroid microcarcinoma (PTMC), develop a protocol for active surveillance (AS), and compare the long-term prognosis, quality of life, and medical costs between the AS and immediate surgery groups. METHODS: This multicenter prospective cohort study of PTMC started in June 2016. The inclusion criteria were suspicious of malignancy or malignancy based on fine needle aspiration or core needle biopsy, age of ≥18 years, and a maximum diameter of ≤1 cm. If there was no major organ involvement, no lymph node/distant metastasis, and no variants with poor prognosis, the patients were explained of the pros and cons of immediate surgery and AS before selecting AS or immediate surgery. Follow-up visits (physical examination, ultrasonography, thyroid function, and questionnaires) are scheduled every 6 months during the first 2 years, and then every 1 year thereafter. Progression was defined as a maximum diameter increase of ≥3, ≥2 mm in two dimensions, suspected organ involvement, or lymph node/distant metastasis. RESULTS: Among 439 enrolled patients, 290 patients (66.1%) chose AS and 149 patients (33.9%) chose immediate surgery. The median follow-up was 6.7 months (range, 0.2 to 11.9). The immediate surgery group had a larger maximum tumor diameter, compared to the AS group (7.1±1.9 mm vs. 6.6±2.0 mm, respectively; P=0.014). CONCLUSION: The results will be useful for developing an appropriate PTMC treatment policy based on its natural course and risk factors for progression.
Biopsy, Fine-Needle ; Biopsy, Large-Core Needle ; Cohort Studies* ; Follow-Up Studies ; Humans ; Neoplasm Metastasis ; Prognosis ; Prospective Studies* ; Quality of Life ; Risk Factors ; Thyroid Gland* ; Thyroid Neoplasms ; Ultrasonography

No abstract available.