Supervised Relation Extraction Between Suicide-Related Entities and Drugs: Development and Usability Study of an Annotated PubMed Corpus.

BACKGROUND: Drug-induced suicide has been debated as a crucial issue in both clinical and public health research. Published research articles contain valuable data on the drugs associated with suicidal adverse events. An automated process that extracts such information and rapidly detects drugs related to suicide risk is essential but has not been well established. Moreover, few data sets are available for training and validating classification models on drug-induced suicide. OBJECTIVE: This study aimed to build a corpus of drug-suicide relations containing annotated entities for drugs, suicidal adverse events, and their relations. To confirm the effectiveness of the drug-suicide relation corpus, we evaluated the performance of a relation classification model using the corpus in conjunction with various embeddings. METHODS: We collected the abstracts and titles of research articles associated with drugs and suicide from PubMed and manually annotated them along with their relations at the sentence level (adverse drug events, treatment, suicide means, or miscellaneous). To reduce the manual annotation effort, we preliminarily selected sentences with a pretrained zero-shot classifier or sentences containing only drug and suicide keywords. We trained a relation classification model using various Bidirectional Encoder Representations from Transformer embeddings with the proposed corpus. We then compared the performances of the model with different Bidirectional Encoder Representations from Transformer-based embeddings and selected the most suitable embedding for our corpus. RESULTS: Our corpus comprised 11,894 sentences extracted from the titles and abstracts of the PubMed research articles. Each sentence was annotated with drug and suicide entities and the relationship between these 2 entities (adverse drug events, treatment, means, and miscellaneous). All of the tested relation classification models that were fine-tuned on the corpus accurately detected sentences of suicidal adverse events regardless of their pretrained type and data set properties. CONCLUSIONS: To our knowledge, this is the first and most extensive corpus of drug-suicide relations.

Prevalence and causative drugs of drug-induced Parkinsonism in pediatric patients.

Although several studies provided evidence on the epidemiology of drug-induced Parkinsonism (DIP) and its causative drugs, it is still limited in pediatrics. This study aimed to investigate the prevalence and risk of DIP in pediatrics. We used the Health Insurance Review and Assessment Service-Pediatric Patients Sample in Korea between 2010 and 2017 to estimate the annual prevalence of DIP and causative drug use using a cross-sectional design. The risk of DIP associated with causative drugs was evaluated using a case-crossover design. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated using a conditional logistic regression. A total of 2925 pediatric patients had diagnosed with DIP from 2010 to 2017. Most patients were aged between 12 and19 years old, and 99.8% had any diagnosis of mental health disorder (MHD). During the study period, the prevalence of DIP increased by 10.0-fold from 2010 to 2017. All causative drugs showed a corresponding increase in their use, with atypical antipsychotics being the most prominent (increase ratio, 2.07). For both in the prevalence of DIP and atypical antipsychotic use, the increment was much bigger in patients with non-psychotic MHD than that in patients with psychotic MHD. In the case-crossover study, antipsychotics showed the largest aOR with DIP. Risperidone among antipsychotics showed the highest risk for DIP (aOR = 7.09, 95% CI = 3.83-13.09), followed by aripiprazole (aOR = 5.03, 95% CI = 2.88-8.80). This study suggests that the increase in DIP prevalence in pediatric patients might be because of the increased use of atypical antipsychotics.

Remission of type 2 diabetes after gastrectomy for gastric cancer: diabetes prediction score.

BACKGROUND: Although type 2 diabetes (T2D) remission after gastric cancer surgery has been reported, little is known about the predictors of postoperative T2D remission. METHODS: This study used data from a nationwide cohort provided by the National Health Insurance Service in Korea. We developed a diabetes prediction (DP) score, which predicted postoperative T2D remissions using a logistic regression model based on preoperative variables. We applied machine-learning algorithms [random forest, XGboost, and least absolute shrinkage and selection operator (LASSO) regression] and compared their predictive performances with those of the DP score. RESULTS: The DP score comprised five parameters: baseline body mass index (< 25 or ≥ 25 kg/m2), surgical procedures (subtotal or total gastrectomy), age (< 65 or ≥ 65 years), fasting plasma glucose levels (≤ 130 or > 130 mg/dL), and antidiabetic medications (combination therapy including sulfonylureas, combination therapy not including sulfonylureas, single sulfonylurea, or single non-sulfonylurea]). The DP score showed a clinically useful predictive performance for T2D remission at 3 years after surgery [training cohort: area under the receiver operating characteristics (AUROC) 0.73, 95% confidence interval (CI), 0.71-0.75; validation cohort: AUROC 0.72, 95% CI 0.69-0.75], which was comparable to that of the machine-learning models (random forest: AUROC 0.71, 95% CI 0.68-0.74; XGboost: AUROC 0.70, 95% CI 0.67-0.73; LASSO regression: AUROC 0.75, 95% CI 0.73-0.78 in the validation cohort). It also predicted the T2D remission at 6 and 9 years after surgery. CONCLUSIONS: The DP score is a useful scoring system for predicting T2D remission after gastric cancer surgery.

Risk of seizures associated with antipsychotic treatment in pediatrics with psychiatric disorders: a nested case-control study in Korea.

Antipsychotic drugs raise seizure risk in adults, and antipsychotic drug use is increasing among pediatric psychiatric disorder patients. However, few studies have examined seizure risk in this younger patient population. To evaluate seizure risk in pediatric patients on antipsychotics, we conducted a nested case-control study using a nationwide database. Patient information was retrieved from the Korean Health Insurance Review and Assessment (HIRA) database from 2008-2018. Antipsychotic use among newly diagnosed psychiatric patients was gathered starting 1 year before the index date and categorized as recent, past, consistent, or none. Seizure cases among these patients were defined based on (1) prescription of antiepileptic drugs or (2) an electroencephalography (EEG) examination among patients with seizure diagnostic code. A conditional logistic regression model was constructed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for seizure risk due to antipsychotic use. In total, 1523 seizure cases and 6092 seizure-free controls aged 8-19 years with newly diagnosed psychiatric disorders were included for analysis. Logistic regression revealed a significant association between antipsychotic use and seizure development (recent users OR = 4.03, 95% CI 3.4-4.79; consistent users: OR = 2.84, 95% CI 2.44-3.3). Seizure risk enhanced further with an increase in the number of antipsychotic drugs used. Risperidone, aripiprazole, quetiapine, olanzapine, paliperidone, and blonanserin were independently associated with greater seizure risk. Pediatric patients receiving antipsychotics, especially new or multiple antipsychotic users, should be carefully monitored for seizure development.

Lifetime survival and medical costs of lung cancer: a semi-parametric estimation from South Korea.

BACKGROUND: It is essential to have information on the disease burden of lung cancer at an individual level throughout the life; however, few such results have been reported. Thus, this study aimed to assess the lifetime disease burden in patients with lung cancer by assessing various factors, such as survival, years of life lost (YLL) and medical expenditure in South Korea based on real-world data and extrapolation. METHODS: Newly diagnosed lung cancer patients (n = 2919) in 2004-2010 were selected and observed until the end of 2015 using nationwide reimbursement claim database. The patients were categorised into the Surgery group, Chemo and/or Radiotherapy group (CTx/RTx), and Surgery+CTx/RTx according to their treatment modality. Age- and sex-matched control subjects were selected from among general population using the life table. The survival and cost data after diagnosis were analysed by a semi-parametric method, the Kaplan-Meier analysis for the first 100 months and rolling extrapolation algorithm for 101-300 months. YLL were derived from the difference in survival between patients and controls. RESULTS: Lifetime estimates (standard error) were 4.5 (0.2) years for patients and 14.5 (0.1) years for controls and the derived YLL duration was 10.0 (0.2) years. Lifetime survival years showed the following trend: Surgery (14.2 years) > Surgery+CTx/RTx (8.5 years) > CTx/RTx group (3.0 years), and YLL were increased as lifetime survival years decreased (2.3, 8.7, 12.2 years, respectively). The mean lifetime medical cost was estimated at 30,857 USD/patient. Patients in the Surgery group paid higher treatment cost in first year after diagnosis, but the overall mean cost per year was lower at 4359 USD compared with 7075USD of Surgery+CTx/RTx or 7626USD of CTx/RTx group. CONCLUSIONS: Lung cancer has resulted in about 10 years of life lost in overall patients. The losses were associated with treatment modality, and the results indicated that diagnosing lung cancer in patients with low stage disease eligible for surgery is beneficial for reducing disease burden in terms of survival and treatment cost per year throughout the life.

Assessing the Labeling Information on Drugs Associated With Suicide Risk: Systematic Review.

BACKGROUND: Drug-induced suicide (DIS) is a severe adverse drug reaction (ADR). Although clinical trials have provided evidence on DIS, limited investigations have been performed on rare ADRs, such as suicide. OBJECTIVE: We aimed to systematically review case reports on DIS to provide evidence-based drug information. METHODS: We searched PubMed to obtain case reports regarding DIS published until July 2021. Cases resulting from drugs that are no longer used or are nonapproved, substance use, and suicidal intentions were excluded. The quality of each case report was assessed using the CASE (Case Reports) checklist. We extracted data regarding demographics, medication history, suicide symptoms, and symptom improvement and evaluated the causality of DIS using the Naranjo score. Furthermore, to identify the potential suicidal risk of the unknown drugs, we compared the results of the causality assessment with those of the approved drug labels. RESULTS: In 83 articles, we identified 152 cases involving 61 drugs. Antidepressants were reported as the most frequent causative drugs of DIS followed by immunostimulants. The causality assessment revealed 61 cases having possible, 89 cases having probable, and 2 cases having definite relationships with DIS. For approximately 85% of suspected drugs, the risk of suicidal ADRs was indicated on the approved label; however, the approved labels for 9 drugs, including lumacaftor/ivacaftor, doxycycline, clozapine, dextromethorphan, adalimumab, infliximab, piroxicam, paclitaxel, and formoterol, did not provide information about these risks. CONCLUSIONS: We found several case reports involving drugs without suicide risk information on the drug label. Our findings might provide valuable insights into drugs that may cause suicidal ADRs.

Discontinuation of blood pressure-lowering, glucose-lowering, and lipid-lowering medications after bariatric surgery in patients with morbid obesity: a nationwide cohort study in South Korea.

BACKGROUND: Limited evidence exists on the patterns of medication use for hypertension, diabetes mellitus (DM), and dyslipidemia after bariatric surgery among Asian patients. OBJECTIVES: To investigate the patterns in the use of blood pressure-lowering, glucose-lowering, and lipid-lowering medications following BS in Korean patients with morbid obesity. SETTING: This study is a retrospective cohort study using the Health Insurance Review and Assignment claims database of South Korea (from 2019 to 2021). METHODS: We included patients who underwent BS between 2019 and 2020 in South Korea. We evaluated the treatment patterns of blood pressure-lowering, glucose-lowering, and lipid-lowering medications at 3-month intervals for 1-year following BS, including medication use, individual medication classes, and the number of medications prescribed. Furthermore, we estimated remission rates for each disorder based on patient characteristics by defining patients who discontinued their medications for at least 2 consecutive quarters as remission. RESULTS: A total of 3810 patients were included in this study. For 1-year following BS, a marked decrease in the number of patients using blood pressure-lowering, glucose-lowering, and lipid-lowering medications was observed. The most remarkable decrease occurred in glucose-lowering medications, which decreased by approximately -75.1% compared with that at baseline. This tendency was consistently observed when analyzing both the number of medications prescribed and the specific medication classes. Regarding remission rates, patients who were female, younger, and received the biliopancreatic diversion-duodenal switch as their BS showed a relatively higher incidence of remission than other groups. CONCLUSIONS: BS was associated with a decrease in the use of medications for hypertension, diabetes mellitus (DM), and dyslipidemia.

The relative importance of friendship to happiness increases with age.

Happiness is predicted by social relationships in general and contact frequency in particular. This study aims to examine if the relative importance of social contacts with the closest family/relative, friend, and neighbor in happiness changes with advancing age. We used data for all participants aged 19 years and older (n = 229,099) in the 2019 Community Health Survey, which measured the frequency of contact with the closest relative/family, neighbor, and friend among a representative sample of Koreans between August 16 and October 31, 2019. The Shapley value decomposition method was used to measure the relative importance of each predictor of happiness. Overall, contact frequency was positively associated with happiness (p<0.001). The relative importance value of contact with the closest family, neighbor, and friend to happiness increased from 4.70%, 3.98%, and 7.35%, respectively, in the 19-29 years group to 8.09%, 4.44%, and 11.00%, respectively, in the 60 years and older group. Frequent interactions with the closest friend could have a greater impact on happiness in old age than those with the closest family and neighbor.

Psychiatric Comorbidities and Schizophrenia in Youths With Attention-Deficit/Hyperactivity Disorder.

Importance: The association between attention-deficit/hyperactivity disorder (ADHD) and schizophrenia has received increased attention; however, evidence on the association between psychiatric comorbidities and subsequent schizophrenia in patients with ADHD is limited. Objective: To investigate the risk of being diagnosed with schizophrenia in children and adolescents with ADHD considering the presence of psychiatric comorbidity. Design, Setting, and Participants: This was a population-based, retrospective cohort study using the Health Insurance Review and Assessment claims database from January 1, 2007, to December 31, 2019. Participants were children and adolescents aged 5 to 19 years who received an ADHD diagnosis between January 1, 2010, and December 31, 2018, in the nationwide claims data of Korea. Data were analyzed from January 2010 to December 2019. Interventions or Exposures: The presence of psychiatric comorbidity was assessed from diagnosis records within 1 year before ADHD diagnosis. Comorbidities were further categorized according to the number of comorbidities and specific comorbid disorders. Main Outcomes and Measures: Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% CIs, examining the association between psychiatric comorbidities and the risk of being diagnosed with schizophrenia. Furthermore, the occurrence of psychiatric comorbidity during the follow-up period was explored among patients without psychiatric comorbidity at baseline. Results: A total of 211 705 patients with newly diagnosed ADHD were included. A total of 157 272 patients (74.3%) were male, and the age of 5 to 9 years showed the highest distribution (115 081 patients [54.4%]). Patients with psychiatric comorbidity had a significantly higher risk of being diagnosed with schizophrenia than those without (adjusted HR, 2.14; 95% CI, 2.05-2.23). The association between schizophrenia and psychiatric comorbidity became progressively greater with the increasing number of comorbidities. Several individual psychiatric disorders showed an association with development of schizophrenia, with ASD, intellectual disability, tic disorder, depression, and bipolar disorder being the top 5 disorders most associated. Furthermore, 3244 patients (73.8%) without psychiatric comorbidities experienced the emergence of other psychiatric disorders before schizophrenia occurrence. Conclusions and Relevance: In this retrospective cohort study involving children and adolescents with ADHD, the presence of psychiatric comorbidity in patients with ADHD was associated with an increased risk of being diagnosed with schizophrenia, with an increased risk observed in multiple comorbidities and a wide variety of comorbidities. These findings highlight the significance of assessing and managing psychiatric comorbidities in patients with ADHD to decrease subsequent schizophrenia risk and allow for early intervention.

Comparison of prediction methods for treatment continuation of antipsychotics in children and adolescents with schizophrenia.

OBJECTIVE: There is little evidence for finding optimal antipsychotic treatment for schizophrenia, especially in paediatrics. To evaluate the performance and clinical benefit of several prediction methods for 1-year treatment continuation of antipsychotics. DESIGN AND SETTINGS: Population-based prognostic study conducting using the nationwide claims database in Korea. PARTICIPANTS: 5109 patients aged 2-18 years who initiated antipsychotic treatment with risperidone/aripiprazole for schizophrenia between 2010 and 2017 were identified. MAIN OUTCOME MEASURES: We used the conventional logistic regression (LR) and common six machine-learning methods (least absolute shrinkage and selection operator, ridge, elstic net, randomforest, gradient boosting machine, and superlearner) to derive predictive models for treatment continuation of antipsychotics. The performance of models was assessed using the Brier score (BS), area under the receiver operating characteristic curve (AUROC) and area under the precision-recall curve (AUPRC). The clinical benefit of applying these models was also evaluated by comparing the treatment continuation rate between patients who received the recommended medication by models and patients who did not. RESULTS: The gradient boosting machine showed the best performance in predicting treatment continuation for risperidone (BS, 0.121; AUROC, 0.686; AUPRC, 0.269). Among aripiprazole models, GBM for BS (0.114), SuperLearner for AUROC (0.688) and random forest for AUPRC (0.317) showed the best performance. Although LR showed lower performance than machine learnings, the difference was negligible. Patients who received recommended medication by these models showed a 1.2-1.5 times higher treatment continuation rate than those who did not. CONCLUSIONS: All prediction models showed similar performance in predicting the treatment continuation of antipsychotics. Application of prediction models might be helpful for evidence-based decision-making in antipsychotic treatment.

Association of Treatment With Antipsychotics, Antidepressants, or Both With Movement Disorders and Seizures Among Children and Adolescents With Depression in Korea.

Importance: Little evidence exists on neurological adverse events (movement disorders and seizures) that occur during adjuvant use of antipsychotics with antidepressants, especially in children and adolescents. Objective: To assess the association between neurological adverse events (movement disorders, including parkinsonism, dystonia, extrapyramidal symptoms, chorea, and tic, and seizures) and the adjuvant use of antipsychotics in children and adolescents with depression. Design, Setting, and Participants: A retrospective cohort study using the Health Insurance Review and Assessment claims database in Korea between 2008 and 2018. The study population was children and adolescents aged 2 to 18 years with depression who began treatment with antidepressants between January 1, 2010, and December 31, 2018. Data were analyzed between December 9, 2020, and December 10, 2021. Exposure: Time-varying exposure to antidepressants, antipsychotics, and concomitant use of antidepressants and antipsychotics. Concomitant use was further subdivided according to the antipsychotic treatment status (dose and agent). Main Outcomes and Measures: The extended Cox proportional hazards regression model, with adjustment for sex, age, health insurance type, psychiatric comorbidities, psychiatric hospitalization, and comedication with other psychotropic drugs, was used to estimate adjusted hazard ratios (aHRs) and 95% CIs for the associations of movement disorders and seizures with use of antidepressants and antipsychotics. Results: A total of 9890 patients were included in the study: 9541 (mean [SD] age, 14.8 [2.8] years; 4956 [51.9%] female) and 7731 (mean [SD] age, 14.9 [2.7] years; 4150 [53.7%] female) met the inclusion criteria for movement disorders and seizures, respectively. For movement disorders, associations were found between concomitant use (aHR, 3.68; 95% CI, 3.06-4.44) and antipsychotic-only use (aHR, 3.84; 95% CI, 3.03-4.87) compared with antidepressant-only use, but their CIs overlapped. The associations with seizure were similar (concomitant use: aHR, 2.06; 95% CI, 1.66-2.55; antipsychotic-only use: aHR, 2.05; 95% CI, 1.53-2.75). With concomitant use, the aHRs gradually increased with increasing doses of antipsychotics. Haloperidol had the highest aHR, 7.15 (95% CI, 3.89-10.00) for movement disorders. The highest aHR for seizure was observed with quetiapine (aHR, 2.36; 95% CI, 1.55-3.59), followed by aripiprazole (aHR, 2.05; 95% CI, 1.52-2.77). Conclusions and Relevance: In this cohort study, adjunctive antipsychotics with antidepressants were associated with movement disorders and seizures compared with antidepressant monotherapy in children and adolescents with depression. These results suggest that careful consideration of the risk-benefit profile of the antipsychotic use as adjuvant therapy in this population is needed.

Survival and medical costs of melanoma patients with subsequent cancer diagnoses: A South Korean population-based retrospective cohort study.

AIM: Subsequent cancers (SCs) after melanoma diagnosis further increases the risks of mortality and medical costs. This population-based analysis aimed to evaluate risk factors for SC, mortality, and medical costs of melanoma patients with SC. METHODS: A retrospective cohort analysis was conducted using a nationwide claims database during 2002-2017 in South Korea. SC was defined as having other types of cancer diagnoses other than subsequent melanoma during-up to 5 years after melanoma diagnosis. Melanoma patients were divided into patients with and without SC, and the overall and subgroup survival rates, the risk of developing SC, and the total medical costs were analyzed using a Kaplan-Meier method and regressions. RESULTS: A total of 3740 melanoma patients were included in the analysis (mean age, 62.3 ± 15.4 y; 47.2% men), and 2273 patients (1157 within 2 months, 756 after 2 months of melanoma diagnosis) had SC. Higher Charlson comorbidity index score and male sex significantly increased the risk of developing SC. Five-year survival rate and cumulative medical costs were 62.3% (95% confidence interval [CI], 60.8-63.9) and $21,413, respectively, in all patients. Patients with SC diagnosed after 2 months showed the lowest survival rate of 47.8% (95% CI, 44.3-51.4) and the highest costs of $27,081, showing a mortality hazard ratio of 1.65 (range, 1.46-1.86) and a cost ratio of 1.189 (range, 1.112-1.271) compared with those without SC. CONCLUSION: This study presented survival outcomes and medical costs in melanoma patients and confirmed that SC after the first diagnosis of melanoma significantly increased disease burden in terms of mortality and medical costs.

Association Between Antipsychotic Treatment and Neurological Adverse Events in Pediatric Patients: A Population-Based Cohort Study in Korea.

Background: Potential adverse effects might be caused by increasing the number of antipsychotic prescriptions. However, the empirical evidence regarding pediatric psychiatric patients is insufficient. Therefore, we explored the antipsychotic-induced adverse effects focusing on the neurological system. Method: Using the medical information of pediatric patients retrieved from the claims data of Health Insurance Review and Assessment in Korea, we identified those psychiatric patients who were started on antipsychotic treatment at age 2-18 years between 2010 and 2018 (n = 10,969). In this study, movement disorders and seizures were considered as major neurological adverse events. The extended Cox model with time-varying covariates was applied to explore the association between antipsychotic medication and adverse events. Findings: Total 1,894 and 1,267 cases of movement disorders and seizures occurred in 32,046 and 33,280 person-years, respectively. The hazard risks of neurological adverse events were 3-8 times higher in the exposed to antipsychotics period than in the non-exposure period. Among the exposure periods, the most dangerous period was within 30 days of cumulative exposure. High doses or polypharmacy of antipsychotics was associated with increased risks of neurological adverse events. Among individual antipsychotics, haloperidol showed the highest risk of developing movement disorders among the examined agents. Quetiapine showed a lower risk of developing movement disorders but a higher risk of developing seizures than risperidone. Conclusion: These findings suggest that antipsychotics should be used with caution in pediatric patients, especially regarding initial exposure, high dose, and polypharmacy.

Cost-effectiveness of Bariatric Surgery for People with Morbid Obesity in South Korea.

OBJECTIVE: This study aimed to evaluate the cost-effectiveness of bariatric surgery (BS) compared to non-surgical treatment (NST) in Korean people with morbid obesity according to comorbidities and body mass index (BMI) severity. METHODS: The target cohort was people with morbid obesity, defined as BMI of ≥ 35 kg/m2, or obese people with BMI of 30-34.9 kg/m2 having obesity-related comorbidities. A decision-tree model for 1-year obesity treatment and Markov model for the rest of life were used. In the decision-tree model, the comorbidity remission rate and BMI change after 1-year treatment were decided based on a prospective clinical trial. In the Markov model, the transition probabilities were calculated considering the BMI level and age. The starting age of 20 years, a cycle length of 1 year, a time horizon of 80 years, and a 5% discount rate were applied for the base case from the healthcare system perspective. RESULTS: In the base case, BS improved quality-adjusted life years (QALYs) and was the cost-effective option in total cohort (incremental cost-effectiveness ratio of BS vs. NST was 674 USD/QALY). It was shown to be cost-effective in all subgroup analyses based on BMI level. In particular, BS was a dominant alternative for the subgroup with basal BMI of 35.0-37.4 kg/m2. Various sensitivity analyses showed the robustness of results indicating the cost-effectiveness of BS. CONCLUSION: BS at BMI of > 30 kg/m2 was more effective than NST for a reduction in BMI and remission of obesity-related comorbidities and was cost-effective in Korea.

Effect of late-life weight change on dementia incidence: a 10-year cohort study using claim data in Korea.

BACKGROUND: The association between body mass index (BMI) in late-life and dementia risk remains unclear. We investigated the association between BMI changes over a 2-year period and dementia in an elderly Korean population. METHODS: We examined 67 219 participants aged 60-79 years who underwent BMI measurement in 2002/2003 and 2004/2005 as part of the National Health Insurance Service-Health Screening Cohort. Baseline characteristics including BMI, socioeconomic status and cardiometabolic risk factors were measured at baseline (2002/2003). The difference between BMI at baseline and at the next health screening (2004/2005) was used to calculate the BMI change. After 2 years, the incidence of dementia was monitored for a mean 5.3 years from 2008 to 2013. Multivariate HRs for dementia incidence were estimated on the basis of baseline BMI and its changes after adjusting for various other risk factors. A subgroup analysis was conducted to determine the effects of baseline BMI and BMI changes. RESULTS: We demonstrated a significant association between late-life BMI changes and dementia in both sexes (men: >-10% HR=1.26, 95% CI 1.08 to 1.46, >+10% HR=1.25, 95% CI 1.08 to 1.45; women: >-10% HR=1.15, 95% CI 1.03 to 1.29, >+10% HR=1.17, 95% CI 1.05 to 1.31). However, the baseline BMI was not associated with dementia, except in underweight men. After stratification based on the baseline BMI, the BMI increase over 2 years was associated with dementia in men with a BMI of <25 kg/m2 and women with a BMI of 18.5-25 kg/m2, but not in the obese subgroup in either sex. However, BMI decrease was associated with dementia in those with a BMI of ≥18.5 kg/m2, but not in the underweight subgroup in either sex. CONCLUSION: Both weight gain and weight loss may be significant risk factors associated with dementia. Continuous weight control and careful monitoring of weight changes are necessary to prevent dementia development.

Prescribing patterns of polypharmacy in Korean pediatric patients.

BACKGROUND: Several studies have examined the risk and health outcomes related to polypharmacy among the elderly. However, information regarding polypharmacy among pediatric patients is lacking. OBJECTIVE: The aim of this study was to investigate the prevalence of polypharmacy and its related factors among the pediatric population of South Korea. METHODS: We used national claim data from the Health Insurance Review and Assessment Service-Pediatric Patients Sample (HIRA-PPS) in Korea originating from 2012 through 2016. Polypharmacy was defined as a daily average of two or more drugs used yearly. Complex chronic conditions (CCCs) were examined to evaluate concomitant chronic diseases in pediatric patients. Age-specific contraindications and potential drug-drug interactions were assessed according to criteria established by the Korea Institute of Drug Safety & Risk Management (KIDS). Descriptive statistics and logistic regression were conducted to analyze the status of polypharmacy and its associated risk factors in pediatric patients. RESULTS: The 5-year prevalence of pediatric polypharmacy in pediatric patients was 3.7%. The prevalence of polypharmacy was much higher in younger pediatric patients: 9.5% for patients between the ages of 1-7 years, 0.9% for ages 6-11 years, and 1.1% for ages 12-19 years. Pediatric patients with CCCs, Medical Aid benefits, or a hospital admission history had a significantly higher prevalence of polypharmacy when compared to their counterparts without those conditions. The most commonly prescribed drugs were respiratory agents (29%) followed by anti-allergic drugs (18.7%), central nervous system agents (15.9%), antibiotics (10.1%), and gastrointestinal drugs (7.7%). There was a positive correlation between the daily average number of inappropriate prescriptions and the degree of polypharmacy, especially in pediatric patients between the ages of 1-7 years. Contraindications and potential drug-drug interactions occurred in 11.0% and 10.1% of patients exposed to polypharmacy, respectively. CONCLUSIONS: One in ten pediatric patients under the age of 7 years was prescribed two or more concurrent drugs on average per day. Furthermore, pediatric patients exposed to polypharmacy showed an increased risk of inappropriate drug use. The implementation of a medication review system that considers pediatric patient polypharmacy exposure would reduce inappropriate drug use and prevent unwanted adverse outcomes.

Economic burden of lung cancer: A retrospective cohort study in South Korea, 2002-2015.

We evaluated the survival rates and medical expenditure in patients with lung cancer using a nationwide claims database in South Korea. A retrospective observational cohort study design was used, and 2,919 lung cancer patients and their matched controls were included. Medical expenditures were analyzed with the Kaplan-Meier sample average method, and patients were categorized into 4 groups by operation and primary treatment method (i.e. Patients with operation: OP = surgery, OP+CTx/RTx = surgery with anti-cancer drugs or radiotherapy; Patients without operation: CTx/RTx = anti-cancer drugs or radiotherapy, Supportive treatment). The 5-year medical expenditure per case was highest in the OP+CTx/RTx group ($36,013), followed by the CTx/RTx ($23,134), OP ($22,686), and supportive treatment group ($3,700). Lung cancer-related anti-cancer drug therapy was the major cost driver, with an average 53% share across all patients. Generalized linear regression revealed that monthly medical expenditure in lung cancer patients, after adjustment for follow-up month, was approximately 3.1-4.3 times higher than that in the control group (cost ratio for OP = 3.116, OP+CTx/RTx = 3.566, CTx/RTx = 4.340, supportive treatment = 4.157). The monthly medical expenditure at end of life was estimated at $2,139 for all decedents, and approximately a quarter of patients had received chemotherapy in the last 3 months. In conclusion, this study presented the quantified treatment costs of lung cancer on various aspects compared with matched controls according to the treatment of choice. In this study, patients with operation incurred lower lifetime treatment costs than patients with CTx/RTx or supportive treatment, indicating that the economic burden of lung cancer was affected by treatment method. Further studies including both cancer stage and treatment modality are needed to confirm these results and to provide more information on the economic burden according to disease severity.