• 제목/요약/키워드: Cohort model

검색결과 392건 처리시간 0.028초

여성 노인에서 출산력과 고관절 골절 발생간의 관련성 : 코호트 연구 (Reproductive History and Hip Fracture in the Elderly Women in Korea : A Cohort Study)

  • 이승미;김윤이;윤경은;박병주
    • Journal of Preventive Medicine and Public Health
    • /
    • 제35권4호
    • /
    • pp.305-312
    • /
    • 2002
  • Objectives : The reproductive history of women has been suggested to have a possible influence on the risk of osteoporotic fractures. The purpose of this study was to assess the association between reproductive history and hip fractures in the elderly women. Methods : The study subjects were drawn from women members of the Korean Elderly Pharmacoepidemiologic Cohort (KEPEC), aged 65 years or over, whose reproductive histories were available, and who were beneficiaries of the Korea Medical Insurance Corporation (KMIC) in 1993 and lived in Busan city, Korea. The information on reproductive histories, and possible confounders, were collected from mailed questionnaires. Potential hip fracture cases were collected from the claims data obtained between 1993 and 1998, with a hospital survey conducted to confirm the final diagnoses. Rate ratios and their 95% confidence intervals, were calculated using a Cox's proportional hazard model. Results : Following up 5,215 women for 6 years, 51 cases were confirmed with hip fractures. When adjusted for age, weight and physical activity, the rate ratio of hip fractures in women who had given birth three or more times was 0.56 (95% CI: 0.25-1.25), compared with those who had given birth two or less times. When adjusted for age, number of births, weight and physical activity, the rate ratio in women who first gave birth when younger than 22 years was 0.60 (95% CI: 0.34-1.08) compared with those who had giving birth at 22 years or older. Conclusions : According to these findings, an early age when first giving birth might decrease the risk of hip fractures in elderly Korean women.

Clinical Prognostic Score for Predicting Disease Remission with Differentiated Thyroid Cancers

  • Somboonporn, Charoonsak;Mangklabruks, Ampica;Thakkinstian, Ammarin;Vatanasapt, Patravoot;Nakaphun, Suwannee
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권6호
    • /
    • pp.2805-2810
    • /
    • 2016
  • Background: Differentiated thyroid cancer is the most common endocrine malignancy with a generally good prognosis. Knowing long-term outcomes of each patient helps management planning. The study was conducted to develop and validate a clinical prognostic score for predicting disease remission in patients with differentiated thyroid cancer based on patient, tumor and treatment factors. Materials and Methods: A retrospective cohort study of 1,217 differentiated thyroid cancer patients from two tertiary-care hospitals in the Northeast of Thailand was performed. Associations between potential clinical prognostic factors and remission were tested by Cox proportional-hazards analysis in 852 patients (development cohort). The prediction score was created by summation of score points weighted from regression coefficients of independent prognostic factors. Risks of disease remission were estimated and the derived score was then validated in the remaining 365 patients (validation cohort). Results: During the median follow-up time of 58 months, 648 (76.1%) patients in the development cohort had disease remission. Five independent prognostic factors were identified with corresponding score points: duration from thyroid surgery to $^{131}I$ treatment (0.721), distant metastasis at initial diagnosis (0.801), postoperative serum thyroglobulin level (0.535), anti-thyroglobulin antibodies positivity (0.546), and adequacy of serum TSH suppression (0.293). The total risk score for each patient was calculated and three categories of remission probability were proposed: ${\leq}1.628$ points (low risk, 83% remission), 1.629-1.816 points (intermediate risk, 87% remission), and ${\geq}1.817$ points (high risk, 93% remission). The concordance (C-index) was 0.761 (95% CI 0.754-0.767). Conclusions: The clinical prognostic scoring model developed to quantify the probability of disease remission can serve as a useful tool in personalized decision making regarding treatment in differentiated thyroid cancer patients.

The Relationship Between Night Shift Work and the Risk of Abnormal Thyroid-Stimulating Hormone: A Hospital-Based Nine-Year Follow-up Retrospective Cohort Study in Taiwan

  • Chen, Hsin-Hao;Chiu, Hsiao-Hui;Yeh, Tzu-Lin;Lin, Chi-Min;Huang, Hsin-Yi;Wu, Shang-Liang
    • Safety and Health at Work
    • /
    • 제12권3호
    • /
    • pp.390-395
    • /
    • 2021
  • Background: Health-care providers typically undergo shift work and are subjected to increased stress. Night shift work may induce disturbed sleep cycles and circadian rhythm. The objective of this study was to explore if night shift workers (NSWs) show an increased risk of abnormal thyroid-stimulating hormone (TSH). Methods: We conducted a retrospective cohort study of 574 employees without thyroid disease and abnormal TSH at baseline who underwent annual check-ups between 2007 and 2016 in a medical center. NSWs were defined as those with working time schedules other than daytime hours. We calculated the incidence rate and estimated the adjusted hazard ratio (HR) for incident abnormal TSH and subclinical hypothyroidism compared with non-NSWs using a Cox regression model. Results: A total of 56 incident abnormal TSH cases and 39 subclinical hypothyroidism cases in NSWs were identified during 3000 person-years of follow-up. In models adjusted for age, sex, obesity, and working departments, we found no increased relative risk for incident abnormal TSH (HR: 0.72, 95% confidence interval: 0.33-1.60) or subclinical hypothyroidism (HR: 0.52, 95% confidence interval: 0.19-1.45) when comparing NSWs to non-NSWs; nor were incidence rates significantly different among exclusively medical employees after excluding administrative staff. Conclusion: In this hospital-based nine-year follow-up retrospective cohort study, NSWs were not associated with increased relative risk of incident abnormal TSH and subclinical hypothyroidism, in contrast to previous cross-sectional studies.

베이비부머의 자본역동과 삶의 질의 구조모형: 출생코호트의 조절효과 (A Structural Model of Baby Boomers' Capital Dynamics and Quality of Life: Moderated by Birth Cohort)

  • 신학진
    • 디지털융복합연구
    • /
    • 제17권8호
    • /
    • pp.429-437
    • /
    • 2019
  • 본 연구는 전주시에 거주하는 베이비부머의 다양한 자본역동과 역동이 삶의 질에 미치는 영향을 확인했다. 더불어 초기와 후기베이비부머로 구분되는 출생코호트의 조절효과를 검증했다. 검증을 위해 303 베이비부머를 대상으로 구조방정식모델링을 적용했다. 연구결과는 첫째, 베이비부머의 인적자본은 심리자본, 경제자본, 사회자본, 삶의 질에 직간접 영향을 미쳤다. 둘째, 경제자본은 심리자본, 사회자본, 삶의 질에 직간접 영향을 미쳤다. 셋째, 심리자본은 사회자본, 삶의 질에 직간접 영향을 미쳤다. 넷째, 사회자본은 삶의 질에 직접 영향을 미쳤다. 다섯째, 출생코호트는 경제자본이 심리자본과 삶의 질에 미치는 영향을 조절했다. 검증된 자원역동과 조절효과는 베이비부머의 삶의 질에 대한 이해와 중재방향을 제공했다. 향후 연구지역을 농촌과 대도시로, 연구대상을 베이비붐 이후세대로 확장을 권고한다.

The Risk of Colorectal Cancer After Cholecystectomy or Appendectomy: A Population-based Cohort Study in Korea

  • Lee, Joonki;Choe, Sunho;Park, Ji Won;Jeong, Seung-Yong;Shin, Aesun
    • Journal of Preventive Medicine and Public Health
    • /
    • 제51권6호
    • /
    • pp.281-288
    • /
    • 2018
  • Objectives: We investigated the association between cholecystectomy or appendectomy and the subsequent risk of colorectal cancer (CRC) in the Korean population. Methods: A retrospective cohort study was conducted with the National Health Insurance Service-National Sample Cohort of Korea; this sample was followed up from January 1, 2002, until the date of CRC incidence, loss to follow-up, or December 31, 2015. The exposure status of cholecystectomy and appendectomy was treated as a time-varying covariate. The calculated risk of CRC was stratified by follow-up period, and the association between these surgical procedures and CRC was investigated by a Cox regression model applying appropriate lag periods. Results: A total of 707 663 individuals were identified for analysis. The study population was followed up for an average of 13.66 years, and 4324 CRC cases were identified. The hazard ratio (HR) of CRC was elevated in the first year after cholecystectomy (HR, 1.71; 95% confidence interval [CI], 1.01 to 2.89) and in the first year and 2-3 years after appendectomy (HR, 4.22; 95% CI, 2.87 to 6.20; HR, 2.34; 95% CI, 1.36 to 4.03, respectively). The HRs of CRC after applying 1 year of lag after cholecystectomy and 3 years of lag after appendectomy were 0.80 (95% CI, 0.57 to 1.13) and 0.77 (95% CI, 0.51 to 1.16), respectively. Conclusions: The risk of CRC increased in the first year after cholecystectomy and appendectomy, implying the possibility of bias. When appropriate lag periods after surgery were applied, no association was found between cholecystectomy or appendectomy and CRC.

Correlation between Physical Activity and Lung Function in Dusty Areas: Results from the Chronic Obstructive Pulmonary Disease in Dusty Areas (CODA) Cohort

  • Han, Yuri;Heo, Yeonjeong;Hong, Yoonki;Kwon, Sung Ok;Kim, Woo Jin
    • Tuberculosis and Respiratory Diseases
    • /
    • 제82권4호
    • /
    • pp.311-318
    • /
    • 2019
  • Background: Although physical activity is known to be beneficial to lung function, few studies have been conducted to investigate the correlation between physical activity and lung function in dusty areas. Therefore, the purpose of this study is to investigate the correlation between physical activity and lung function in a Korean cohort including normal and COPD-diagnosed participants. Methods: Data obtained from the COPD in dusty areas (CODA) cohort was analyzed for the following factors: lung function, symptoms, and information about physical activity. Information on physical activity was valuated using questionnaires, and participants were categorized into two groups: active and inactive. The evaluation of the mean lung function, modified Medical Research Council dyspnea grade scores, and COPD assessment test scores was done based on the participant physical activity using a general linear model after adjusting for age, sex, smoking status, pack-years, height, and weight. In addition, a stratification analysis was performed based on the smoking status and COPD. Results: Physical activity had a correlation with high forced expiratory volume in 1 second ($FEV_1$) among CODA cohort (p=0.03). While the active group exhibited significantly higher $FEV_1$ compared to one exhibited by the inactive group among past smokers (p=0.02), no such correlation existed among current smokers. There was no significant difference observed in lung function after it was stratified by COPD. Conclusion: This study established a positive correlation between regular physical activity in dusty areas and lung function in participants.

The Prognostic Value of Lymph Node Ratio after Neoadjuvant Chemotherapy in Patients with Locally Advanced Gastric Adenocarcinoma

  • Zhu, Kankai;Jin, Hailong;Li, Zhijian;Gao, Yuan;Zhang, Qing;Liu, Xiaosun;Yu, Jiren
    • Journal of Gastric Cancer
    • /
    • 제21권1호
    • /
    • pp.49-62
    • /
    • 2021
  • Purpose: This study aimed to investigate the prognostic value of lymph node ratio (LNR) in patients with locally advanced gastric cancer who received neoadjuvant chemotherapy. Materials and Methods: We retrospectively enrolled gastric cancer patients treated with neoadjuvant chemotherapy and curative surgery at the First Affiliated Hospital of Zhejiang University from 2004 to 2015 as the study cohort. Patients with the same inclusion criteria treated in 2016-2017 were enrolled as the validation cohort. Kaplan-Meier curves were assessed using the log-rank test to analyze the differences in overall survival (OS). Multivariate survival analysis was performed using the Cox proportional hazards model. The areas under the receiver operating characteristic curve of ypN and LNR categories for predicting the actual 3-year OS were compared. Results: A total of 265 patients were included in the proposal cohort. The median number of retrieved lymph nodes (rLNs) was 32. The number of positive lymph nodes (pLNs) increased as rLN increased (P=0.037), but the LNR remained relatively constant (P=0.462). The LNR was categorized into 4 groups according to the prognosis: ypNr0, node-negative with rLN>25; ypNr1, node-negative with rLN≤25 or 00.3. In the validation cohort of 43 enrolled patients, there was a clear distinction in OS that significantly (P<0.001) varied depending on the LNR values and LNR was the only independent prognostic factor in multivariate analysis (P<0.001). Conclusions: LNR was an independent prognostic factor for survival of patients with gastric cancer after preoperative chemotherapy and might be an alternative predictor for ypN stage.

동집단 자료의 주의력 결핍 과잉행동 장애를 종점으로 한 납의 벤치마크 용량 하한 도출 (Derivation of benchmark dose lower limit of lead for ADHD based on a longitudinal cohort data set)

  • 김병수;김대희;하미나;권호장
    • Journal of the Korean Data and Information Science Society
    • /
    • 제25권5호
    • /
    • pp.987-998
    • /
    • 2014
  • 본 연구에서는 우리나라 환경부에서 최근에 구축한 아동 동집단 경시적 자료인 아동 건강과 환경 연구 (CHEER) 자료에 기초하여 주의력 결핍 과잉행동 장애 (ADHD)와 혈중 납 농도의 상관을 선형혼합모형을 사용하여 규명하고, CHEER 자료의 경시적 특성으로 나타나는 ADHD 점수의 "평균으로의 회귀" 현상을 보고하고자 한다. 또한 ADHD를 종점으로 한 혈중 납 농도의 용량-반응 곡선을 도출하며, 이렇게 도출된 용량-반응 곡선에 기초하여 몇 가지 상황 하에서 독성기준치인 벤치마크 용량 하한 (BMDL)을 유도한다.

아동청소년 성폭력 피해자들을 위한 코호트 연구 : 코호트 구축과 초기 평가 결과 (A Cohort Study of Children and Adolescents Victims with Sexual Abuse in Korea and Their Initial Assessment Results)

  • 김경윤;이나현;천근아;송동호
    • 정신신체의학
    • /
    • 제27권1호
    • /
    • pp.13-24
    • /
    • 2019
  • 연구목적 코호트 연구의 목적은 국내 아동청소년 성폭력 피해자 코호트 시스템 구축과 피해자들의 정신건강에 작용하는 위험요인과 보호요인을 규명하기 위함이며, 이 연구는 코호트 참여자들의 참여 당시 초기 평가 결과를 분석한 예비 결과이다. 방 법 서울 해바라기아동센터를 통해 3년 7개월간 모집한 19세 이하의 65명 아동청소년 성폭력 피해자 및 그 가족들의 인구학적, 성폭력 관련 요인 및 정신심리학적 상태와 정신건강학적 진단을 평가하여 초기자료를 분석하였다. 결 과 초기 평가 자료의 예비 분석 결과는 다음과 같다. 여성 대상자 56명, 대상자 평균나이 12.4세(SD=4.4), 성폭력 추행 71.8%, 친족 및 지인 가해자 87.1% 였고, 피해자의 61.5%가 성폭력 피해와 관련된 정신의학적 진단을 받았으며 이중 외상 후 스트레스 장애가 29.2%, 우울장애가 23.1%로 나타났다. 피해 이후 발고까지 걸린 기간은 평균 1.5년이었다. IES-R-K, TSCYC 외상 후 스트레스장애-회피 항목과 CBCL의 총문제행동 항목이 임상적으로 유의하게 증가한 결과를 나타내었다. 결 론 아동청소년 성폭력 피해자는 정신건강학적 문제가 발생할 위험성이 높은 경향을 가지고 있다. 코호트 연구는 국내 성폭력 피해자들의 정신건강에 영향을 미치는 위험요인과 보호요인을 확인하고 예측모형을 설립할 수 있을 것이다.

Development of a Risk Scoring Model to Predict Unexpected Conversion to Thoracotomy during Video-Assisted Thoracoscopic Surgery for Lung Cancer

  • Ga Young Yoo;Seung Keun Yoon;Mi Hyoung Moon;Seok Whan Moon;Wonjung Hwang;Kyung Soo Kim
    • Journal of Chest Surgery
    • /
    • 제57권3호
    • /
    • pp.302-311
    • /
    • 2024
  • Background: Unexpected conversion to thoracotomy during planned video-assisted thoracoscopic surgery (VATS) can lead to poor outcomes and comparatively high morbidity. This study was conducted to assess preoperative risk factors associated with unexpected thoracotomy conversion and to develop a risk scoring model for preoperative use, aimed at identifying patients with an elevated risk of conversion. Methods: A retrospective analysis was conducted of 1,506 patients who underwent surgical resection for non-small cell lung cancer. To evaluate the risk factors, univariate analysis and logistic regression were performed. A risk scoring model was established to predict unexpected thoracotomy conversion during VATS of the lung, based on preoperative factors. To validate the model, an additional cohort of 878 patients was analyzed. Results: Among the potentially significant clinical variables, male sex, previous ipsilateral lung surgery, preoperative detection of calcified lymph nodes, and clinical T stage were identified as independent risk factors for unplanned conversion to thoracotomy. A 6-point risk scoring model was developed to predict conversion based on the assessed risk, with patients categorized into 4 groups. The results indicated an area under the receiver operating characteristic curve of 0.747, with a sensitivity of 80.5%, specificity of 56.4%, positive predictive value of 1.8%, and negative predictive value of 91.0%. When applied to the validation cohort, the model exhibited good predictive accuracy. Conclusion: We successfully developed and validated a risk scoring model for preoperative use that can predict the likelihood of unplanned conversion to thoracotomy during VATS of the lung.