Disparities in cause-specific mortality by health insurance type and premium: evidence from Korean NHIS-HEALS cohort study, 2002-2019.

BACKGROUND: Although one's socioeconomic status affects health outcomes, limited research explored how South Korea's National Health Insurance (NHI) system affects mortality rates. This study investigated whether health insurance type and insurance premiums are associated with mortality. METHODS: Based on the National Health Insurance Service-Health Screening cohort, 246,172 men and 206,534 women aged ≥ 40 years at baseline (2002-2003) were included and followed until 2019. Health insurance type was categorized as employee-insured (EI) or self-employed-insured (SI). To define low, medium, and high economic status groups, we used insurance premiums at baseline. Death was determined using the date and cause of death included in the cohort. Cox proportional hazard models were used to analyze the association between insurance factors and the overall and cause-specific mortality. RESULTS: The SI group had a significantly higher risk of overall death compared to the EI group (adjusted hazard ratio (HR) [95% confidence interval]: 1.13 [1.10-1.15] for men and 1.18 [1.15-1.22] for women), after adjusting for various factors. This trend extended to death from the five major causes of death in South Korea (cancer, cardiovascular disease, cerebrovascular disease, pneumonia, and intentional self-harm) and from external causes, with a higher risk of death in the SI group (vs. the EI group). Further analysis stratified by economic status revealed that individuals with lower economic status faced higher risk of overall death and cause-specific mortality in both sexes, compared to those with high economic status for both health insurance types. CONCLUSION: This nationwide study found that the SI group and those with lower economic status faced higher risk of overall mortality and death from the five major causes in South Korea. These findings highlight the potential disparities in health outcomes within the NHI system. To address these gaps, strategies should target risk factors for death at the individual level and governments should incorporate such strategies into public health policy development at the population level. TRIAL REGISTRATION: This study was approved by the Institutional Review Board of Chungbuk National University Hospital (CBNUH-202211-HR-0236) and adhered to the principles of the Declaration of Helsinki (1975).

Association between polycythemia and risk of ischemic stroke in males based on the national health insurance service-health screening cohort.

BACKGROUND: Polycythemia, a state in which the hematocrit or hemoglobin (Hb) concentration in the peripheral blood increases, is associated with several thrombosis-related diseases, of which cerebral infarction is relatively common. This study aimed to investigate the association between ischemic stroke and polycythemia, as a potential risk factor. RESEARCH DESIGN AND METHODS: This study included men who had undergone national health checkups between 2002 and 2003; the data were extracted from the Korean National Health Insurance Service-Health Screening database. The primary outcome was the risk ischemic stroke; adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for ischemic stroke were calculated using Cox proportional hazards regression models. RESULTS: In total, 207,737 male participants aged 40-79 years were included in this study. At the baseline, 13972 (6.7%) participants met the polycythemia criteria (Hb >16.5 g/dL). During the study period, 897 and 12,440 cases of ischemic stroke occurred in the polycythemia and normocythemia (13.0 g/dL ≤ Hb ≤16.5 g/dL) groups, respectively. Compared with the normocythemia group, the polycythemia group showed an adjusted HR (95% CI) for ischemic stroke of 1.12 (1.04-1.20). CONCLUSIONS: The risk of ischemic stroke was higher in participants with polycythemia than in those with normocythemia.

Metformin Use May Increase Risk of Pancreatic Cancer in Diabetic Women: An Analysis of the Korean National Health Insurance Service-National Health Screening Cohort Database.

BACKGROUND: In addition to its antidiabetic effects, metformin has pleiotropic effects, such as the inhibition of carcinogenesis. This study aimed to investigate the association between metformin use and pancreatic cancer risk in the Korean National Health Insurance Service (NHIS)-National Health Screening Cohort (HEALS). METHODS: Of the individuals in the Korean NHIS-HEALS, 29,271 men and 19,091 women were included in the final analysis after propensity score matching based on age, body mass index, and smoking status. The study population was categorized into three groups: metformin non-users with diabetes mellitus (DM), metformin users with DM, and non-diabetic users. A Cox proportional hazards regression model was used to examine the association between metformin use and pancreatic cancer. RESULTS: The median follow-up period was 12.9 years. The estimated pancreatic cancer incidence was highest in metformin users with DM, regardless of sex (P<0.001), and lowest in non-diabetic men and female metformin non-users (P=0.053). The hazard ratios (95% confidence interval) for pancreatic cancer incidence in metformin users and non-diabetic individuals were 1.116 (0.648-1.923) and 0.447 (0.259-0.771) in men and 2.769 (1.003-7.642) and 1.451 (0.529-3.984) in women, respectively, after full adjustment. CONCLUSION: Women with diabetes using metformin are at a higher risk of pancreatic cancer than women with diabetes not using metformin. Meanwhile, men with DM using metformin have a similar risk of pancreatic cancer as men with DM not using metformin.

Recent trends in opioid prescriptions in Korea from 2002 to 2015 based on the Korean NHIS-NSC cohort.

OBJECTIVES: Opioids are prescribed to treat moderate to severe pain. We investigated recent trends in opioid (morphine, oxycodone, fentanyl, and hydromorphone) prescriptions using data from the Korean National Health Insurance Service-National Sample Cohort between 2002 and 2015. METHODS: The morphine milligram equivalent (MME) was calculated to standardize the relative potency of opioids. The number (cases) or amount (MME) of annual opioid prescriptions per 10,000 registrants was computed to analyze trends in opioid prescriptions after age standardization. Joinpoint regression analysis was conducted to calculate the annual percentage change and average annual percentage change (AAPC). RESULTS: The number (cases) of prescriptions per 10,000 registrants increased from 0.07 in 2002 to 41.23 in 2015 (AAPC, 76.0%; 95% confidence interval [CI], 61.6 to 91.7). The MME per 10,000 registrants increased from 15.06 in 2002 to 40,727.80 in 2015 (AAPC, 103.0%; 95% CI, 78.2 to 131.3). The highest AAPC of prescriptions and MME per 10,000 registrants were observed in the elderly (60-69 years) and in patients treated at general hospitals. Fentanyl prescriptions increased most rapidly among the 4 opioids. CONCLUSIONS: Consumption of opioids greatly increased in Korea over the 14-year study period.

The association between triglyceride-glucose index, cardio-cerebrovascular diseases, and death in Korean adults: A retrospective study based on the NHIS-HEALS cohort.

BACKGROUND: The triglyceride-glucose (TyG) index is a reliable indicator of insulin resistance. We aimed to investigate the TyG index in relation to cardio-cerebrovascular diseases (CCVDs and mortality. METHODS: This retrospective study included 114,603 subjects. The TyG index was categorized into four quartiles by sex: Q1, <8.249 and <8.063; Q2, 8.249‒<8.614 and 8.063‒<8.403; Q3, 8.614‒< 8.998 and 8.403‒<8.752; and Q4, ≥8.998 and ≥8.752, in men and women, respectively. To calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the primary outcomes (CCVDs and all-cause mortality) and secondary outcomes (cardiovascular diseases [CVDs], cerebrovascular diseases [CbVDs], CCVD-related deaths, or all-cause deaths), Cox proportional hazards regression models were adopted. RESULTS: Compared to Q1, the HRs (95% CIs) for the primary outcomes of Q2, Q3, and Q4 were 1.062 (0.981‒1.150), 1.110 (1.024-1.204), and 1.151 (1.058-1.252) in men and 1.099 (0.986-1.226), 1.046 (0.938-1.166), and 1.063 (0.954-1.184) in women, respectively, after adjusted for age, smoking status, drinking status, physical activity, body mass index, systolic blood pressure, low-density lipoprotein cholesterol, economic status, and anti-hypertensive medications. Fully adjusted HRs (95% CIs) for CVDs of Q2, Q3, and Q4 were 1.114 (0.969-1.282), 1.185 (1.031-1.363), and 1.232 (1.068-1.422) in men and 1.238 (1.017-1.508), 1.183 (0.971-1.440), and 1.238 (1.018-1.505) in women, respectively. The adjusted HRs (95% CIs) for ischemic CbVDs of Q2, Q3, and Q4 were 1.005 (0.850-1.187), 1.225 (1.041-1.441), and 1.232 (1.039-1.460) in men and 1.040 (0.821-1.316), 1.226 (0.981-1.532), and 1.312 (1.054-1.634) in women, respectively, while the TyG index was negatively associated with hemorrhagic CbVDs in women but not in men. The TyG index was not significantly associated with CCVD-related death or all-cause death in either sex. CONCLUSIONS: Elevated TyG index was positively associated with the primary outcomes (CCVDs and all-cause mortality) in men and predicted higher risk of CVDs and ischemic CbVDs in both sexes.

Metformin use in cancer survivors with diabetes reduces all-cause mortality, based on the Korean National Health Insurance Service between 2002 and 2015.

ABSTRACT: Malignant neoplasms are the leading cause of death in Korea. We aimed to examine if metformin use in cancer survivors reduces all-cause mortality. This study was retrospectively designed based on data from the Korean National Health Insurance Service-National Health Screening Cohort (HEALS) between 2002 and 2015. The Kaplan-Meier estimator and log-rank test was performed to estimate the survival function according to metformin usage (3721 metformin non-users with diabetes, 5580 metformin users with diabetes, and 24,483 non-diabetic individuals). Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated using Cox proportional hazards regression models.The median follow-up duration was 4.2 years. The HRs (95% CIs) for all-cause mortality of metformin users and the non-diabetic group were 0.762 (0.683-0.850) and 1.055 (0.966-1.152) in men and 0.805 (0.649-0.999), and 1.049 (0.873-1.260) in women, respectively, compared with metformin non-users among diabetic cancer survivors, in a fully adjusted model. After stratifying metformin users into pre- and post-diagnosis of cancers, adjusted HRs (95% CIs) of pre- and post-diagnosis metformin users for all-cause mortality were 0.948 (0.839-1.071) and 0.530 (0.452-0.621) in men and 1.163 (0.921-1.469) and 0.439 (0.323-0.596) in women, respectively.Metformin use in cancer survivors with diabetes reduced overall mortality rates. In particular, metformin use after cancer diagnosis, not before cancer diagnosis, was inversely associated with overall mortality.Active treatment with metformin for diabetic cancer survivors after cancer diagnosis can improve their survival rates.

Metformin usage and the risk of colorectal cancer: a national cohort study.

PURPOSE: This study aimed to investigate the association between metformin usage and the risk of colorectal cancer (CRC) using data from the Korean National Health Insurance Service-National Health Screening Cohort database. METHODS: Data from the NHIS-HEALS cohort between 2002 and 2015 were longitudinally analyzed. Subjects were divided into three groups: metformin non-users with diabetes mellitus (DM), metformin users with DM, and no DM group. CRC was defined using the ICD-10 code (C18.0-C20.0) at the time of admission. Cox proportional hazard regression models were adopted after stepwise adjustment for confounders to investigate the association between metformin usage and colorectal cancer risk. RESULTS: During the follow-up period, of the total 323,430 participants, 2341 (1.33%) of the 175,495 males and 1204 (0.81%) of the 147,935 females were newly diagnosed with CRC. The estimated cumulative incidence of CRC was significantly different among the three groups based on Kaplan-Meier's survival curve (p values < 0.05 in both sexes). Compared with metformin non-users, hazard ratios (95% CIs) of metformin users and the no DM group were 0.66 (0.51-0.85) and 0.72 (0.61-0.85) in males and 0.59 (0.37-0.92) and 0.93 (0.66-1.29) in females, respectively, after being fully adjusted. CONCLUSIONS: Metformin users with diabetes appear to have a significantly lower risk of CRC compared with metformin non-users.

Metformin use reduced the overall risk of cancer in diabetic patients: A study based on the Korean NHIS-HEALS cohort.

BACKGROUND AND AIM: Several studies have reported the preventive effect of metformin on cancer development. This study aimed to investigate the relationship between use of metformin and risk of cancer in Koreans. METHODS AND RESULTS: This study was designed retrospectively using the National Health Insurance Service-National Health Screening Cohort conducted between 2002 and 2015. 40 to 69-year-old subjects who received a health screening examination from 2002 to 2003 were enrolled. Hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer were estimated in a multivariate Cox proportional regression analysis. A total of 323,430 subjects was enrolled (301,905 individuals without diabetes [No DM], 8643 diabetic patients with metformin treatment [metformin users], and 12,882 diabetic patients without metformin treatment [metformin non-users]). The median follow-up period was 12.7 years. Cumulative incidence of overall cancer was 7.9% (7.7, 10.3, and 11.1% in No DM, metformin users and non-users, respectively). Compared to metformin non-users, the fully adjusted HRs (95% CIs) of metformin users and No DM for overall cancer incidence were 0.73 (0.66-0.81) and 0.75 (0.64-0.88), respectively, in men and 0.83 (0.78-0.89) and 0.81 (0.72-0.92) in women. CONCLUSIONS: Diabetic patients receiving metformin treatment, and individuals without diabetes were at lower risk for cancer incidence than diabetic patients without metformin treatment.

Diabetes, Metformin, and Lung Cancer: Retrospective Study of the Korean NHIS-HEALS Database.

BACKGROUND: Metformin is the first option in managing type 2 diabetes mellitus (DM) and has pleotropic effects. We studied the incidence of lung cancer in patients who received metformin therapy. PATIENTS AND METHODS: This study was retrospectively designed and based on the Korean National Health Insurance Service-National Health Screening Cohort to determine whether metformin reduces lung cancer risk in the diabetic population. At baseline, all participants were 40 to 69 years old and were categorized into 3 groups: metformin nonrecipients with DM, metformin recipients with DM, and the nondiabetic group. RESULTS: A total of 336,168 individuals were included in the final analysis (314,291 nondiabetic individuals, 8806 metformin recipients, and 13,071 metformin nonrecipients). The study median follow-up period was 12.86 years. The estimated cumulative lung cancer incidence of metformin nonrecipients, metformin recipients, and the nondiabetic group was 1.80%, 1.97%, and 1.24% in men and 1.87%, 0.61%, and 0.41% in women, respectively (P < .05). Compared to metformin nonrecipients, the hazard ratios (95% confidence intervals) for lung cancer incidence of metformin recipients and the nondiabetic group were 1.287 (0.979-1.691) and 0.835 (0.684-1.019) in men and 0.664 (0.374-1.177) and 0.553 (0.359-0.890) in women, respectively. The hazard ratios (95% confidence intervals) were statistically significant in male ever smokers (0.784 [0.627-0.979]) and female nonsmokers (0.498 [0.320-0.774]) after stratification according to smoking status. CONCLUSION: Metformin therapy did not reduce lung cancer incidence in the diabetic population. However, individuals without DM were at a lower risk of lung cancer, especially in male ever smokers and female nonsmokers.

Metformin use reduced the risk of stomach cancer in diabetic patients in Korea: an analysis of Korean NHIS-HEALS database.

BACKGROUND: Diabetes mellitus (DM) increases atherosclerotic cardiovascular complications and cancer risks. Stomach cancer is the most common cancer in Korea. Although the survival rate of stomach cancer has improved, the disease burden is still high. METHODS: This retrospective study investigated the association between metformin use and stomach cancer incidence in a Korean population using the National Health Insurance Service-National Health Screening Cohort database. Participants aged 40-80 years old at the baseline period (2002-2003) were enrolled. The study population was categorized into three groups of metformin non-users with DM, metformin users with DM, and individuals without DM (No DM group). RESULTS: A total of 347,895 participants (14,922 metformin non-users, 9891 metformin users, and 323,082 individuals without DM) were included in the final analysis. The median follow-up duration was 12.70 years. The estimated cumulative incidence of stomach cancer was highest in metformin non-users and lowest in the No DM group (men vs. women: 3.75 vs. 1.97% in metformin non-users, 2.91 vs. 1.53% in metformin users, and 2.54 vs. 0.95% in the No DM group). Compared with metformin non-users, the hazard ratios (95% confidence intervals) for stomach cancer incidence of metformin users and the No DM group were 0.710 (0.579-0.870) and 0.879 (0.767-1.006) in men and 0.700 (0.499-0.981) and 0.701 (0.544-0.903) in women, respectively, after full adjustment. CONCLUSIONS: Metformin users with DM in the Korean population were at lower risk of stomach cancer incidence after controlling for potential confounding factors.

Inverse Association between Statin Use and Stomach Cancer Incidence in Individuals with Hypercholesterolemia, from the 2002-2015 NHIS-HEALS Data.

Purpose: To investigate the association between statin use and stomach cancer incidence in individuals with hypercholesterolemia. Materials and methods: To examine the cumulative effect of statins, we defined a statin user as one who used statins during 2002-2003 at baseline. Statin users were further classified into high and low users according to the medication possession rate. Statin non-users consisted of participants who had never used statins during the entire period of 2002-2015, despite having hypercholesterolemia (total cholesterol level ≥250 mg/dL at baseline). Ultimately, 17,737 statin users and 13,412 statin non-users were used in the analysis. We performed survival analyses, considering the diagnosis of stomach cancer as an event of interest. Results: Median follow-up duration was 12.9 years. The cumulative incidence rates of stomach cancer were lowest in high users (1.90% in men and 0.98% in women). Compared to non-users, hazard ratios (95% confidential intervals) for stomach cancer of low users and high users were 0.953 (0.755-1.203) and 0.526 (0.399-0.693) in men and 0.629 (0.457-0.865) and 0.370 (0.256-0.535) in women, respectively, after adjusting for possible confounders. Conclusions: We observed an inverse association between statin use and stomach cancer incidence in participants with hypercholesterolemia.

Statin use increased new-onset diabetes in hypercholesterolemic individuals: Data from the Korean National Health Insurance Service-National Health Screening Cohort database (NHIS-HEALS).

AIM: We investigated the association between statin use and new-onset diabetes (NODM) in Korean adults with hypercholesterolemia. METHODS: This study performed based on data from the National Health Insurance Service-National Health Screening Cohort for the years from 2002 to 2015. Statin users classified as high- or low- users according to medication possession ratio. Statin non-users consisted of hypercholesterolemic participants who never used statin over the entire follow-up period. 21,469 participants (10,880 statin users, 10,589 statin non-users) with a median follow-up period of 12.5 years were included. We estimated the NODM risk based on the survival analyses. In particular, to adjust for confounding effects, we considered Cox proportional hazards regression models over three stages. RESULTS: Compared to non-users, statin users had a significantly higher risk for NODM. The fully adjusted hazard ratios (aHRs) (95% confidential intervals [95% CIs]) of statin users for NODM were 1.43 (1.31-1.57) in men, and 1.86 (1.66-2.10) in women, respectively after adjusted confounding factors including age and lifestyle factors. Compared to high-users, aHRs (95% CIs) of low-users for NODM were 1.16 (1.03-1.30) and 1.28 (1.16-1.43) in men and women, respectively. CONCLUSIONS: In hypercholesterolemic patients, statin users have a higher risk of NODM than non-users.

Association between statin use and all-cause mortality in cancer survivors, based on the Korean health insurance service between 2002 and 2015.

BACKGROUND AND AIMS: Cancer is the number one cause of death in Korea. This study aimed to investigate if statin use in cancer survivors was inversely associated with all-cause mortality. METHODS AND RESULTS: Data from the 2002 to 2015 National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS) were used. The Kaplan-Meier estimator was used to estimate the survival function according to statin usage. Cox proportional hazards regression models were adopted after stepwise adjustment for potential confounders to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality. The median follow-up duration was 10.0 years. Statin users had a higher percentage of diabetes and hypertension in both sexes. Survival rates of statin users were higher than non-users (p-values <0.001 in men and 0.021 in women). Compared to non-users, the HRs (95% CIs) of statin users for all-cause mortality were 0.327 (0.194-0.553) in men and 0.287 (0.148-0.560) in women after adjustment for potential confounding factors. CONCLUSIONS: Statin users in cancer survivors had higher survival rate than non-users in both sexes.

Statin use and site-specific risk of colorectal cancer in individuals with hypercholesterolemia from the National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS).

BACKGROUND AND AIMS: We investigated the association between statin use and site-specific risk of colorectal cancer in individuals with hypercholesterolemia. METHODS AND RESULTS: This study is based on the National Health Insurance Service-National Health Screening Cohort, conducted during 2002-2015. Statin users were classified as high and low users according to medication possession ratio (MPR). Statin nonusers comprised participants who did not use statins during the entire follow-up period. In total, 17,737 statin users and 13,412 statin nonusers were included in the analysis, with a median follow-up period of 12.7 years. Cox proportional hazards regression models were adopted after stepwise adjustment for confounders to investigate prospective association between statin usage and colorectal cancer risk. In total, 378 (2.3%) of 16,588 male participants and 239 (1.6%) of 14,561 female participants had colorectal cancer during the follow-up period. Compared to nonusers, fully adjusted hazard ratios (HRs) (95% confidence intervals [95% CIs]) for colorectal cancer risk in high statin users were 0.56 (0.42-0.75) in men and 0.64 (0.46-0.90) in women. In men, the fully adjusted HRs for proximal and rectal cancer for high users were 0.29 (0.15-0.56) and 0.52 (0.35-0.78), respectively, compared to those for nonusers. In women, statistical significance was seen only in rectal cancer (HR 0.43 [0.25-0.72]) but not in proximal or distal colon cancer. CONCLUSIONS: High statin users with hypercholesterolemia were associated with lower risk of overall colorectal cancer, especially proximal colon cancer in men and rectal cancer in both sexes.

Inverse Association Between Statin Use and Overall Cancer Incidence in Individuals With Hypercholesterolemia, Based on the Korean Health Insurance Service Between 2002 and 2015.

The Korean National Health Insurance Service provided the Health Screening Cohort Database. To investigate the cumulative effect of statins on cancer development, we defined statin users as those who used statins during 2002 to 2003 at baseline. Statin users were divided into high and low users. Statin nonusers were defined as individuals who had never used statins during the entire period of 2002 to 2015, despite having hypercholesterolemia. In total, 17 737 statin users and 13 412 statin nonusers were included in the final analyses. The median follow-up duration was 12.6 years. Compared with nonusers, the hazard ratios (95% confidential intervals) for any cancer incidence of low users and high users were 1.047 (0.941-1.164) and 0.663 (0.589-0.747) in men and 1.057 (0.938-1.190) and 0.592 (0.517-0.678) in women, respectively, after fully adjusting for possible confounding factors. An inverse association between statin use and any cancer incidence in individuals with hypercholesterolemia was observed.

High Receipt of Statins Reduces the Risk of Lung Cancer in Current Smokers With Hypercholesterolemia: The National Health Insurance Service-Health Screening Cohort.

BACKGROUND: The incidence and mortality of lung cancer have risen steadily with the increasing popularity of tobacco smoking. Observational studies suggest that statins, which are widely used to lower cholesterol, may prevent lung cancer; however, other studies have produced conflicting results. We investigated the effect of statin receipt on lung cancer risk in Korean men according to smoking status. PATIENTS AND METHODS: We collected data from the 2002-2015 National Health Insurance Service-National Health Screening Cohort (NHIS-HEALS). We included a total of 16,588 men in the final analysis. We classified the participants as having high or low statin receipt or as not receiving statins. We used Cox proportional hazards regression models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for lung cancer risk by statin receipt after adjusting for potential confounders. RESULTS: We identified 363 patients with a new diagnosis of lung cancer from 2005 to 2015. Compared to participants who did not receive statins, high statin receipt resulted in a reduced lung cancer risk (HR = 0.64; 95% CI, 0.47, 0.85) after adjustment for confounders. Among current smokers, the fully adjusted HR for high statin receipt compared to those who did not receive statin therapy was 0.50 (95% CI, 0.32, 0.79). CONCLUSION: High statin receipt was associated with lower risk of lung cancer in Korean men with hypercholesterolemia, especially current smokers.

Randomized trial of subfascial infusion of ropivacaine for early recovery in laparoscopic colorectal cancer surgery.

BACKGROUND: There is a need for investigating the analgesic method as part of early recovery after surgery tailored for laparoscopic colorectal cancer (LCRC) surgery. In this randomized trial, we aimed to investigate the analgesic efficacy of an inverse 'v' shaped bilateral, subfascial ropivacaine continuous infusion in LCRC surgery. METHODS: Forty two patients undergoing elective LCRC surgery were randomly allocated to one of two groups to receive either 0.5% ropivacaine continuous infusion at the subfascial plane (n = 20, R group) or fentanyl intravenous patient controlled analgesia (IV PCA) (n = 22, F group) for postoperative 72 hours. The primary endpoint was the visual analogue scores (VAS) when coughing at postoperative 24 hours. Secondary end points were the VAS at 1, 6, 48, and 72 hours, time to first flatus, time to first rescue meperidine requirement, rescue meperidine consumption, length of hospital stay, postoperative nausea and vomiting, sedation, hypotension, dizziness, headache, and wound complications. RESULTS: The VAS at rest and when coughing were similar between the groups throughout the study. The time to first gas passage and time to first rescue meperidine at ward were significantly shorter in the R group compared to the F group (P = 0.010). Rescue meperidine was administered less in the R group; however, without statistical significance. Other study parameters were not different between the groups. CONCLUSIONS: Ropivacaine continuous infusion with an inverse 'v ' shaped bilateral, subfascial catheter placement showed significantly enhanced bowel recovery and analgesic efficacy was not different from IV PCA in LCRC surgery.

A Model for Predicting the Future Risk of Incident Erosive Esophagitis in an Asymptomatic Population Undergoing Regular Check-ups.

Erosive esophagitis is a major risk factor for Barrett esophagus and esophageal adenocarcinoma. Information regarding the putative risk factors for developing erosive esophagitis is considerably heterogeneous; thus, a risk model is required to clinically predict the incidence of erosive esophagitis. This study was to derive and validate a predictive model for the incidence of developing erosive esophagitis after negative index endoscopy in a population subjected to routine health check-ups. This retrospective cohort study of health check-ups included 11,535 patients who underwent repeated screening endoscopy after >3 years from a negative index endoscopy. We used logistic regression analysis to predict the incidence of erosive esophagitis, and a Simple Prediction of Erosive Esophagitis Development score for risk assessment was developed and internally validated using the split-sample approach. The development and validation cohorts included 5765 patients (675 with erosive esophagitis [11.7%]) and 5770 patients (670 with erosive esophagitis [11.6%]), respectively. The final model included sex, smoking behavior, body mass index, hypertension, and the triglyceride level as variables. This model predicted 667 cases of erosive esophagitis, yielding an expected-to-observed ratio of 1.00 (95% confidence interval [CI], 0.92-1.07). A simplified 5-item risk scoring system based on coefficients was developed, with a risk of erosive esophagitis of 6.2% (95% CI, 5.2-7.1) for the low-risk group (score ≤2), 15.1% (95% CI, 13.5-16.6) for the intermediate-risk group (score ≤3, 4), and 18.2% (95% CI, 15.2-21.3) for the high-risk group (score ≥5). The discriminative performance of the risk-prediction score was consistent in the derivation cohort and validation cohort (c-statistics 0.68 and 0.64, respectively); the calibration was good (Brier score 0.099 and 0.1, respectively). In conclusion, a simple risk-scoring model using putative risk factors can predict the future incidence of developing erosive esophagitis in asymptomatic populations.

ROC Estimation from Clustered Data with an Application to Liver Cancer Data.

In this article, we propose a regression model to compare the performances of different diagnostic methods having clustered ordinal test outcomes. The proposed model treats ordinal test outcomes (an ordinal categorical variable) as grouped-survival time data and uses random effects to explain correlation among outcomes from the same cluster. To compare different diagnostic methods, we introduce a set of covariates indicating diagnostic methods and compare their coefficients. We find that the proposed model defines a Lehmann family and can also introduce a location-scale family of a receiver operating characteristic (ROC) curve. The proposed model can easily be estimated using standard statistical software such as SAS and SPSS. We illustrate its practical usefulness by applying it to testing different magnetic resonance imaging (MRI) methods to detect abnormal lesions in a liver.

Identification of Imaging Predictors Discriminating Different Primary Liver Tumours in Patients with Chronic Liver Disease on Gadoxetic Acid-enhanced MRI: a Classification Tree Analysis.

OBJECTIVES: To identify predictors for the discrimination of intrahepatic cholangiocarcinoma (IMCC) and combined hepatocellular-cholangiocarcinoma (CHC) from hepatocellular carcinoma (HCC) for primary liver cancers on gadoxetic acid-enhanced MRI among high-risk chronic liver disease (CLD) patients using classification tree analysis (CTA). METHODS: A total of 152 patients with histopathologically proven IMCC (n = 40), CHC (n = 24) and HCC (n = 91) were enrolled. Tumour marker and MRI variables including morphologic features, signal intensity, and enhancement pattern were used to identify tumours suspicious for IMCC and CHC using CTA. RESULTS: On CTA, arterial rim enhancement (ARE) was the initial splitting predictor for assessing the probability of tumours being IMCC or CHC. Of 43 tumours that were classified in a subgroup on CTA based on the presence of ARE, non-intralesional fat, and non-globular shape, 41 (95.3 %) were IMCCs (n = 29) or CHCs (n = 12). All 24 tumours showing fat on MRI were HCCs. The CTA model demonstrated sensitivity of 84.4 %, specificity of 97.8 %, and accuracy of 92.3 % for discriminating IMCCs and CHCs from HCCs. CONCLUSIONS: We established a simple CTA model for classifying a high-risk group of CLD patients with IMCC and CHC. This model may be useful for guiding diagnosis for primary liver cancers in patients with CLD. KEY POINTS: • Arterial rim enhancement was the initial splitting predictor on CTA. • CTA model achieved high sensitivity, specificity, and accuracy for discrimination of tumours. • This model may be useful for guiding diagnosis of primary liver cancers.