Effects of depression on medication adherence in HIV/AIDS patients: Korea HIV/AIDS cohort study.

BACKGROUND: The number of people with HIV/AIDS has consistently increased in Korea since the first case of HIV/AIDS infection was reported in 1985. The depressive symptoms of patients with HIV/AIDS may lead to medication non-adherence. This study sought to investigate the cross-sectional and longitudinal association between depression and antiretroviral treatment adherence in the Korean HIV/AIDS population. METHODS: We included participants of the Korea HIV/AIDS cohort study between 2009 and 2017. All information was collected at the enrollment and every annual visit, including sociodemographic characteristics, health-related behaviors, HIV/AIDS infection-related factors, depression score, and frequency of skipped medication. We performed a cross-sectional analysis of 601 participants registered between 2009 and 2017. Longitudinal data were evaluated by panel regression analysis in 515 patients who registered from 2009 to 2013. RESULTS: In cross-sectional analysis, the HIV/AIDS patients with depressive symptoms were more likely to be non-adherent (adjusted OR = 0.52, 95 % CI 0.34, 0.79, p = 0.002). Medication adherence was significantly associated with a health-related lifestyle; the adjusted odds ratio of the non-smoking and non-drinking group was 1.75 (95 % CI 1.05, 2.90, p = 0.031). The longitudinal panel regression model revealed a significant negative impact of depression on medication adherence (adjusted OR = 0.50, 95 % CI 0.30, 0.84, p = 0.009). Non-smoking and non-drinking participants were 2.31 times more likely to adhere to antiretroviral treatment (95 % CI 1.29, 4.15, p = 0.005). CONCLUSIONS: Our finding of depression and lifestyle modifications being significant contributors underscore the importance of proactive interventions to optimize the treatment outcomes of PLWH.

Effect of Pharmacist-Led Intervention in Elderly Patients through a Comprehensive Medication Reconciliation: A Randomized Clinical Trial.

PURPOSE: Polypharmacy can cause drug-related problems, such as potentially inappropriate medication (PIM) use and medication regimen complexity in the elderly. This study aimed to investigate the feasibility and effectiveness of a collaborative medication review and comprehensive medication reconciliation intervention by a pharmacist and hospitalist for older patients. MATERIALS AND METHODS: This comprehensive medication reconciliation study was designed as a prospective, open-label, randomized clinical trial with patients aged 65 years or older from July to December 2020. Comprehensive medication reconciliation comprised medication reviews based on the PIM criteria. The discharge of medication was simplified to reduce regimen complexity. The primary outcome was the difference in adverse drug events (ADEs) throughout hospitalization and 30 days after discharge. Changes in regimen complexity were evaluated using the Korean version of the medication regimen complexity index (MRCI-K). RESULTS: Of the 32 patients, 34.4% (n=11/32) reported ADEs before discharge, and 19.2% (n=5/26) ADEs were reported at the 30-day phone call. No ADEs were reported in the intervention group, whereas five events were reported in the control group (p=0.039) on the 30-day phone call. The mean acceptance rate of medication reconciliation was 83%. The mean decreases of MRCI-K between at the admission and the discharge were 6.2 vs. 2.4, although it was not significant (p=0.159). CONCLUSION: As a result, we identified the effect of pharmacist-led interventions using comprehensive medication reconciliation, including the criteria of the PIMs and the MRCI-K, and the differences in ADEs between the intervention and control groups at the 30-day follow-up after discharge in elderly patients. TRIAL REGISTRATION: (Clinical trial number: KCT0005994).

Seasonal influenza vaccine uptake among adults with disabilities in Korea.

BACKGROUND: Previous research on vaccination among people with disabilities has focused on children or adolescents. OBJECTIVE: To examine variations in seasonal influenza vaccination (SIV) uptake according to disability type and age group and explore the vulnerable groups and risk factors of non-vaccination to identify areas of policy support in Korea. METHODS: This pooled cross-sectional study included adults who participated in the 2011, 2014, and 2017 National Survey of Persons with Disabilities. The dependent variable was SIV uptake. Age-stratified multivariate logistic regression was conducted to assess its relationship with disability characteristics. RESULTS: Among 18,069 adults with disabilities, the overall SIV uptake rate increased with age (33.8%, 50.1%, and 85.3% in 20-49, 50-65, and ≥65 years, respectively). In the multivariate analyses (reporting the adjusted odds ratio and 95% confidence interval), severe disability was associated with lower and higher SIV uptake rates in older adults and younger age-groups (0.88, 0.76-1.01; 1.62, 1.42-1.86; and 1.54, 1.24-1.92 in those aged ≥65; 50-64; and 20-49 years), respectively. Health behaviors (regular doctor visits, general health examinations, and non-smoking) were significantly associated with higher odds of SIV uptake. After adjusting for covariates (age, medical conditions, functional ability, and behavioral factors), individuals with brain, epileptic, and psychiatric disabilities showed lower odds of SIV uptake compared to those with internal organ disabilities across all age groups. CONCLUSIONS: Policy initiatives that can improve the health behaviors of people with disabilities (especially the elderly and people with intellectual, brain, epilepsy, and psychiatric disabilities) to promote SIV uptake are needed.

Drug Lag and Associated Factors for Approved Drugs in Korea Compared with the United States.

(1) Background: Drug lag, the delay between the first global regulatory approval and approval by the national health authorities in other countries, impacts the accessibility of drugs. Although the Korean pharmaceutical market has grown significantly, most of its innovative drugs for public health depend on imports from foreign pharmaceutical markets. (2) Methods: We extracted data from the official websites of the Korean Ministry of Food and Drug Safety (MFDS) and the US Food and Drug Administration. Information on new molecule entity drugs, approved as imported drugs by MFDS from 2000 to 2019, was extracted. Multivariate Cox proportional hazard models on drug approval were estimated. (3) Results: In total, 424 drugs were analyzed. Orphan drugs designated by MFDS were less likely to receive approval (HR = 0.731, 95% CI: 0.572-0.934). The drugs with Korean MAHs were less likely to obtain drug approval than those with MAHs of subsidiaries of multinational pharmaceutical companies (HR = 0.524, 95% CI: 0.371-0.738). In the analyses for non-orphan drugs (n = 37), oncology drugs that need local clinical study (HR = 0.247, 95% CI: 0.093-0.657) and drugs that need more patients in a local clinical study (HR = 0.993, 95% CI: 0.988-0.999) were less likely to receive approval, with longer drug lag. The higher number of clinical studies in Korea was associated with a shorter drug lag (HR = 2.133, 95% CI: 1.196-3.805). (4) Conclusions: Our findings imply that Korean pharmaceutical companies should augment their research capabilities for new drug development. Furthermore, consideration of orphan drugs used in rare diseases is needed for drug approval to ensure the availability of these drugs in the market without approval delays.

Mental Disorders and Suicide Risk among Cancer Patients: A Nationwide Cohort Study.

Although cancer patients are known to experience mental disorders and face suicide risk, little is known about the relationship between mental illness and death by suicide in this group. As such, this study aims to examine the association between mental disorders and suicide risk among cancer patients. We used nationally representative cohort data, and included newly diagnosed cancer patients from 2004 to 2012 with whom we followed-up throughout 2013. We used the clinical diagnoses of all mental disorders as an independent variable and suicide death as a dependent variable to estimate the adjusted hazard ratio (AHR) of suicide deaths in patients with cancer using a Cox proportional hazard model. Among total cancer patients (n = 36,220), the 10,567 patients with mental disorders showed higher suicide risk than non-cancer patients (AHR, 1.53; 95% confidence interval [CI], 1.07-2.17), particularly in those who experienced mental disorders prior to cancer diagnosis (AHR, 2.24; 95% CI, 1.35-3.71). Suicide risk among cancer patients who had mood disorders (AHR, 2.23, 95% CI, 1.31-3.81) or anxiety and somatoform disorders (AHR, 1.61, 95% CI, 1.02-2.55) was higher than for those without mental disorders. Suicide risk of stomach (AHR, 3.32; 95% CI, 1.36-8.10) and liver (AHR, 7.57; 95% CI, 1.86-30.72) cancer patients who had mental disorders was higher than for patients without mental disorders. Cancer patients with mental disorders are at increased risk for suicide. During follow-ups after cancer diagnosis, early mental health support needs were provided to patients with mental disorders.

Cost-Effectiveness Analysis of Home-Based Hospice-Palliative Care for Terminal Cancer Patients.

Purpose: We compared cost-effectiveness parameters between inpatient and home-based hospice-palliative care services for terminal cancer patients in Korea. Methods: A decision-analytic Markov model was used to compare the cost-effectiveness of hospice-palliative care in an inpatient unit (inpatient-start group) and at home (home-start group). The model adopted a healthcare system perspective, with a 9-week horizon and a 1-week cycle length. The transition probabilities were calculated based on the reports from the Korean National Cancer Center in 2017 and Health Insurance Review & Assessment Service in 2020. Quality of life (QOL) was converted to the quality-adjusted life week (QALW). Modeling and cost-effectiveness analysis were performed with TreeAge software. The weekly medical cost was estimated to be 2,481,479 Korean won (KRW) for inpatient hospice-palliative care and 225,688 KRW for home-based hospice-palliative care. One-way sensitivity analysis was used to assess the impact of different scenarios and assumptions on the model results. Results: Compared with the inpatient-start group, the incremental cost of the home-start group was 697,657 KRW, and the incremental effectiveness based on QOL was 0.88 QALW. The incremental cost-effectiveness ratio (ICER) of the home-start group was 796,476 KRW/QALW. Based on one-way sensitivity analyses, the ICER was predicted to increase to 1,626,988 KRW/QALW if the weekly cost of home-based hospice doubled, but it was estimated to decrease to -2,898,361 KRW/QALW if death rates at home doubled. Conclusion: Home-based hospice-palliative care may be more cost-effective than inpatient hospice-palliative care. Home-based hospice appears to be affordable even if the associated medical expenditures double.

Potentially inappropriate prescribing of cardiovascular system and antiplatelet/anticoagulant drugs among elderly patients: a Korean population-based national study.

OBJECTIVES: To investigate the prevalence of potentially inappropriate prescribing (PIP) for cardiovascular system (CVS) and antiplatelet/anticoagulant (AP/AC) drugs among Korean elderly patients, using the Screening Tool of Older Persons' Prescriptions (STOPP) criteria version 2 and to identify the risk factors related to PIP. METHODS: The 2016 National Aged Patient Sample data, comprising National Health Insurance claim records for a random sample of 20% of patients aged ≥ 65 years, were used to calculate PIP prevalence of outpatient prescriptions. For criteria including drug-disease interactions, PIP prevalence per indication was estimated. RESULTS: Among 1,274,148 elderly patients and 27,062,307 outpatient prescription claims, 100,085 patients (7.85%) and 341,664 claims (1.27%) had one or more PIP. The most frequent PIP was "non-steroidal anti-inflammatory drug with concurrent antiplatelet agent (s) without proton-pump inhibitor prophylaxis" in the claim-level (0.97%) and patient-level (6.33%) analyses. "Beta-blocker with bradycardia" (16.47% of claims) and "angiotensin receptor blockers in patients with hyperkalaemia" (23.89% of claims) showed the highest PIP prevalence per indication. Logistic regression analysis revealed that, among the patient and health care provider characteristics, female, older age, more severe comorbidities, polypharmacy, higher level of healthcare organization, and specialty of prescriber were significantly associated with a higher risk of PIP. CONCLUSIONS: Our findings of a high prevalence of PIP for CVS and AP/AC drugs among the elderly suggest that an effective strategy is urgently needed to improve the prescription practices of these drugs.

Immediate and Long-Term Outcomes of Reperfusion Therapy in Patients With Cancer.

Background and Purpose: Patients with acute stroke are often accompanied by comorbidities, such as active cancer. However, adequate treatment guidelines are not available for these patients. The purpose of this study was to evaluate the association between cancer and the outcomes of reperfusion therapy in patients with stroke. Methods: We compared treatment outcomes in patients who underwent reperfusion therapy, using a nationwide reperfusion therapy registry. We divided the patients into 3 groups according to cancer activity: active cancer, nonactive cancer, and without a history of cancer. We investigated reperfusion processes, 24-hour neurological improvement, adverse events, 3-month functional outcome, and 6-month survival and related factors after reperfusion therapy. Results: Among 1338 patients who underwent reperfusion therapy, 62 patients (4.6%) had active cancer, 78 patients (5.8%) had nonactive cancer, and 1198 patients (89.5%) had no history of cancer. Of the enrolled patients, 969 patients received intravenous thrombolysis and 685 patients underwent endovascular treatment (316 patients received combined therapy). Patients with active cancer had more comorbidities and experienced more severe strokes; however, they showed similar 24-hour neurological improvement and adverse events, including cerebral hemorrhage, compared with the other groups. Although the functional outcome at 3 months was poorer than the other groups, 36.4% of patients with active cancer showed functional independence. Additionally, 52.9% of the patients with determined stroke etiology showed functional independence despite active cancer. During the 6-month follow-up, 46.6% of patients with active cancer died, and active cancer was independently associated with poor survival (hazard ratio, 3.973 [95% CI, 2.528­6.245]). Conclusions: In patients with active cancer, reperfusion therapy showed similar adverse events and short-term outcomes to that of other groups. While long-term prognosis was worse in the active cancer group than the nonactive cancer groups, not negligible number of patients had good functional outcomes, especially those with determined stroke mechanisms.

A comparison of medication adherence and viral suppression in antiretroviral treatment-naïve patients with HIV/AIDS depending on the drug formulary.

Antiretroviral treatment (ART) adherence is highlighted in management of patients living with human immunodeficiency virus. In South Korea, ART medication research has rarely been conducted due to the low economic burden associated with government-funded treatment. This cross-sectional study aimed to compare the pill burden impact between ART regimen compliance and HIV-RNA viral load suppression. Data were collected from 2008 to 2016 at a general hospital in South Korea. A total of 210 HIV/AIDS treatment-naïve patients were grouped as follows: single-tablet regimen (STR, one tablet/day), mild pill burden (two-four tablets/day), and heavy pill burden (≥ five tablets/day). Patients were analyzed according to gender, age at index date, medical insurance type, comorbidities, depression, HIV/AIDS disease burden as indicated by HIV-RNA viral load and CD4, and laboratory variables. In a multivariate logistic regression model, the STR group demonstrated adherence 5.10 times more often than the heavy pill burden group. Females and patients with an initial viral load of 500,000 or more were 0.090- and 0.040-fold less adherent to the ART regimen. Among these patients, 95% or more of the MPR group were 7.38 times more likely to have a lower limit of detection (LLOD) of viral load suppression. The highest initial viral load group was 0.090-fold less likely to have an LLOD than the reference group. These results suggest that a single-tablet regimen could improve medication adherence and the clinical virologic outcome. Therefore, general population research on ART adherence and polypharmacy is needed.

Smoking Cessation, Weight Change, Diabetes, and Hypertension in Korean Adults.

INTRODUCTION: This study investigates the association of smoking cessation and postcessation weight gain with the development of type 2 diabetes mellitus and hypertension. METHODS: A total of 96,524 individuals without diabetes mellitus and hypertension aged ≥20 years between 2006 and 2008 were included, with follow-up until December 31, 2015. Smoking status and weight changes were monitored for 2 years. Hazard ratios and 95% CIs were calculated for the respective risks of the 2 conditions. Analyses were completed in 2020. RESULTS: Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.90 (95% CI=0.85, 0.96) and 1.00 (95% CI=0.95, 1.05) in recent quitters, 0.89 (95% CI=0.84, 0.95) and 0.92 (95% CI=0.88, 0.97) in long-term quitters, and 0.82 (95% CI=0.78, 0.86) and 0.92 (95% CI=0.89, 0.95) in never smokers. Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.86 (95% CI=0.80, 0.93) and 0.98 (95% CI=0.92, 1.04) in recent quitters with no weight gain, 0.94 (95% CI=0.87, 1.03) and 1.00 (95% CI=0.94, 1.07) in those with 0.1-5 kg weight gain, 0.93 (95% CI=0.73, 1.19) and 1.14 (95% CI=0.96, 1.36) in those with 5.1-10 kg weight gain, and 1.49 (95% CI=0.84, 2.62) and 1.10 (95% CI=0.68, 1.77) in those with a weight gain of >10 kg. CONCLUSIONS: Smoking cessation with no subsequent weight gain is associated with a reduced risk of developing type 2 diabetes. However, weight gain after smoking cessation attenuates the reduced risk of type 2 diabetes. The association between recent quitting and incident hypertension was nonsignificant, whereas long-term quitters had reduced risk of developing hypertension and type 2 diabetes.

Association of smoking cessation after new-onset type 2 diabetes with overall and cause-specific mortality among Korean men: a nationwide population-based cohort study.

INTRODUCTION: This study aimed to examine the association between smoking cessation after new-onset type 2 diabetes and overall and cause-specific mortality risks among Korean men. RESEARCH DESIGN AND METHODS: The Korean National Health Insurance Service-National Health Screening Cohort database was searched, and 13 377 Korean men aged ≥40 years diagnosed with new-onset type 2 diabetes between 2004 and 2007 were included and followed up until 2013. We defined smoking status changes by comparing participants' answers in the last survey before diagnosis to those in the first survey after diagnosis. We estimated the adjusted HR (AHR) and 95% CI for mortality risk using multivariable Cox proportional hazards regression models. RESULTS: We identified 1014 all-cause mortality events (cancer, n=406 and cardiovascular disease (CVD), n=184) during an average follow-up duration of 7.2 years. After adjustment for all confounding factors, the reduced risk of all-cause mortality was more significant among short-term quitters (AHR 0.78; 95% CI 0.64 to 0.95), long-term quitters (AHR 0.68; 95% CI 0.54 to 0.85), and never smokers (AHR 0.66; 95% CI 0.56 to 0.78) compared with current smokers (p for trend <0.001). The lower risk of mortality from cancer was significant among the short-term quitters (AHR 0.60; 95% CI 0.44 to 0.83), long-term quitters (AHR 0.67; 95% CI 0.46 to 0.90), and never smokers (AHR 0.50; 95% CI 0.39 to 0.65) compared with current smokers (p for trend <0.001). There was no significant association between changes in smoking status and death from CVD. Smoking cessation after diagnosis in non-obese individuals (AHR 0.73; 95% CI 0.58 to 0.92) and exercisers (AHR 0.54; 95% CI 0.38 to 0.76) was significantly associated with reduced mortality risk than current smoking. CONCLUSIONS: Smoking cessation after new-onset type 2 diabetes was associated with reduced mortality risk.

Association of employment status and income with self-rated health among waged workers with disabilities in South Korea: population-based panel study.

OBJECTIVE: This study aimed to examine the association of employment status and income with self-rated health among waged workers with disabilities in South Korea. METHODS: This study used the Panel Survey of Employment for the Disabled from 2011 to 2015. A total of 951 waged workers with disabilities were selected as baseline subjects in 2011 and were followed up for 5 years. This study used a generalised linear mixed model after adjusting for covariates. RESULTS: Among 951 waged workers with disabilities, the results showed that 39.3% of workers with disabilities reported poor self-rated health. Workers with disabilities with a precarious employment status and lower income were 1.22 (95% CI 1.21 to 1.23) and 1.81 (95% CI 1.80 to 1.83) times more likely to have poor self-rated health than those with permanent employment and higher income, respectively. A subgroup analysis found that precarious workers with disabilities in lower income households had higher possibilities of poor self-rated health. CONCLUSION: This study suggests that precarious employment and lower income of waged workers with disabilities are significantly associated with poor self-rated health compared with those with permanent jobs or higher income.

Body mass index and clinical outcomes in patients after ischaemic stroke in South Korea: a retrospective cohort study.

OBJECTIVES: Although obesity is a risk factor for stroke, its impact on mortality in patients with stroke remains unclear. In this study, we aimed to evaluate the relationship between body mass index (BMI) and mortality due to ischaemic stroke among adults aged 20 years and above in Korea. DESIGN: Retrospective cohort study. SETTING: A tertiary-hospital-based stroke registry linked to the death records. PARTICIPANTS: 3599 patients admitted for ischaemic stroke from January 2007 to June 2013. OUTCOME MEASURES: The HRs for all-cause and stroke-related mortality were calculated using Cox proportional hazards models. Progression from stroke-related mortality was assessed using the Fine-Grey competing risk model, treating other-cause mortality as a competing risk. Adjustments were made for age, gender, smoking status, Charlson comorbidity index, cardiovascular or non-cardiovascular comorbidities, stroke severity, severity related to other medical conditions, complications and enrolment year. We repeated the analysis with stratification based on age groups (less than 65 vs 65 years and above). RESULTS: For stroke-related mortality, there was no significant difference among the four BMI groups. The risk of all-cause mortality was 36% higher in the underweight group than in the normal weight group (long-term HR=1.36, 95% CI: 1.04 to 1.79), whereas the mortality risk of the obese group was significantly lower (HR=0.66, 95% CI: 0.54 to 0.81). Although this relationship was not estimated in the younger group, it was found that obesity had a protective effect on the all-cause mortality in the elderly (long-term HR=0.66, 95% CI: 0.52 to 0.83). CONCLUSIONS: Obesity is more likely to reduce mortality risk than normal weight, especially in elderly patients.

Utilization patterns of insulin for patients with type 2 diabetes from national health insurance claims data in South Korea.

Type 2 diabetes mellitus (T2DM) is a chronic disease that requires long-term therapy and regular check-ups to prevent complications. In this study, insurance claim data from the National Health Insurance Service (NHIS) of Korea were used to investigate insulin use in T2DM patients according to the economic status of patients and their access to primary physicians, operationally defined as the frequently used medical care providers at the time of T2DM diagnosis. A total of 91,810 participants were included from the NHIS claims database for the period between 2002 and 2013. The utilization pattern of insulin was set as the dependent variable and classified as one of the following: non-use of antidiabetic drugs, use of oral antidiabetic drugs only, or use of insulin with or without oral antidiabetic drugs. The main independent variables of interest were level of income and access to a frequently-visited physician. Multivariate Cox proportional hazards analysis was performed. Insulin was used by 9,281 patients during the study period, while use was 2.874 times more frequent in the Medical-aid group than in the highest premium group [hazard ratio (HR): 2.874, 95% confidence interval (CI): 2.588-3.192]. Insulin was also used ~50% more often in the patients managed by a frequently-visited physician than in those managed by other healthcare professionals (HR: 1.549, 95% CI: 1.434-1.624). The lag time to starting insulin was shorter when the patients had a low income and no frequently-visited physicians. Patients with a low level of income were more likely to use insulin and to have a shorter lag time from diagnosis to starting insulin. The likelihood of insulin being used was higher when the patients had a frequently-visited physician, particularly if they also had a low level of income. Therefore, the economic statuses of patients should be considered to ensure effective management of T2DM. Utilizing frequently-visited physicians might improve the management of T2DM, particularly for patients with a low income.

Healthcare use among persons with visual impairment: Difference-in-difference estimations.

BACKGROUND: Studies on healthcare service use among persons with visual impairments in countries with different healthcare systems are needed for drawing global inferences. OBJECTIVE: The goal was to assess the impact of visual impairment on healthcare service use. METHODS: A retrospective cohort study on health insurance claims data from the National Health Insurance System (NHIS) was conducted. All data from 2002 to 2013 for 2206 and 8824 persons with and without visual impairments, respectively, were extracted and aggregated monthly, generating a total of 162,876 and 568,459 person-month observations, respectively. The dependent variable was total expenditures. Difference-in-difference estimations based on a multivariate log-normal random-effect regression were employed. RESULTS: Persons with visual impairments spent 5.7% and 6.8% more on total healthcare expenditures per month and outpatient healthcare expenditures, respectively, than those without visual impairments, after adjusting for pre-impairment differences. Further results revealed an upward trend in expenditures, particularly among those with visual impairments; this increase was the highest during the year prior impairment (approximately 32% and 21% more for total and outpatient services, respectively, compared with baseline). Inpatient healthcare expenditures showed a similar increase (by approximately 26%) during the year prior impairment compared with baseline; however, the magnitude dropped to approximately 14% and 6% during the 1st and 2nd years of impairment, respectively. Conversely, the annual pattern of expenditure increase was parallel over time for persons without visual impairments, regardless of service. CONCLUSION: Our findings suggest a need for health management and effective care use, particularly the year prior to visual impairment onset.

Potentially inappropriate medication and hospitalization/emergency department visits among the elderly in Korea.

OBJECTIVE: To investigate the association between potentially inappropriate medicine (PIM) use, defined using the American Geriatric Society (AGS) 2012 Beers criteria, and the risk of hospitalization or emergency department (ED) visits in elderly patients, and to examine the most frequently used PIMs among patients with adverse outcomes. DESIGN/SETTING: This was a retrospective study using National Health Insurance claims data from 2010 to 2012. INTERVENTION(S): Elderly patients who took PIMs are compared to those who were not taking PIMs. STUDY PARTICIPANTS: Elderly patients (n = 79 552) who visited medical institutions in Jeju Island during 2011. MAIN OUTCOME MEASURE: Hospitalization and ED visits were evaluated according to whether the patients took PIMs during the study period. The most frequent medications used by the PIM group were also investigated. RESULTS: The likelihood of hospitalization was higher in older patients who took at least one PIM than in those who were not taking PIMs during the study period (odds ratio 2.25, 95% confidence interval 2.09-2.44). Patients taking PIMs were more likely to visit EDs (odds ratio 1.59, 95% confidence interval 1.50-1.67). Among patients who were hospitalized or visited EDs, 45.5% had taken at least one PIM on that day. The most commonly used PIMs included chlorpheniramine maleate, diazepam, metoclopramide HCl and diclofenac sodium. CONCLUSION: Our findings indicate that PIM use can lead to negative health consequences, providing further evidence of the inappropriateness of these medications. Thus, pharmaceutical policies regarding PIM use may need to be implemented for elderly adults in Korea.

Health Behaviors and Medication Adherence in Elderly Patients.

PURPOSE: To explore the relationships of selected health behaviors to medication adherence. DESIGN: A retrospective cohort study. SETTING: Data from Korean national health insurance claims between January 2010 and June 2011. SUBJECTS: Patients aged 65 years and older with hypertension (N = 662,170), hyperlipidemia (N = 244,702), or diabetes (N = 179,285). MEASURES: Medication adherence as a medication possession ratio from January to June 2011 as a dependent variable. The waist circumference (cm) and the body mass index (weight in kilogram divided by height in meter squared) as a marker for obesity. Smoking, drinking, and physical activity as main independent variables. ANALYSIS: A multivariate logistic regression. RESULTS: Nonobese patients, as based on the waist circumference, were more likely to adhere to their medication (by 8.9% for hypertension, 6.2% for diabetes, and 3.5% for hyperlipidemia). Current smokers were less likely to adhere to their medication (by 8.7% for hypertension and 6.8% for diabetes), and moderate and heavy drinkers were also less likely to show medication adherence for diabetes (by 12.9% and 6.4%). Mild physical activity was related to a 1.1% to 1.8% increase in the likelihood of medication adherence across the three disease groups. CONCLUSION: Health promotion programs for self-care health behaviors of elderly patients should emphasize good medication adherence to achieve successful self-management of diseases.

Assessment of the Price-Volume Agreement Program in South Korea.

The Price-Volume Agreement Program (PVAP) was promulgated in 2007 in South Korea as the first attempt to adjust drug pricing according to total consumption in order to contain drug expenditure. This study was designed to assess the impact of the PVAP on diabetes drug expenditure for a period of a 10-year period (2003-2012) using claims data from the National Health Insurance Service. We estimated a multilevel mixed-effects linear regression model by comparing the level of total monthly diabetes drug expenditure for drugs subject to PVAP and existing drugs after adjusting the average differences in drug expenditure before and after the PVAP. The monthly total expenditure for drugs that were newly listed through the PVAP (negotiation drugs) was 7.03% higher on average compared to that for existing drugs, controlling for the baseline differences in expenditure before and after the PVAP. This increase was observed in all four subgroups of diabetes drugs, including sitagliptin, vildagliptin, exenatide, and others. The growth rate of total diabetes drug expenditure was reduced after the PVAP despite the sustained escalation of expenditure levels, which may imply that the PVAP has the potential to be an effective tool for drug expenditure control in the long term.

Effects of delisting nonprescription combination drugs on health insurance expenditures for pharmaceuticals in Korea.

In November 2006, 727 combination drugs in 24 therapeutic classes were delisted in the national formulary in Korea to reduce the country's pharmaceutical expenditure, making these 727 drugs non-reimbursable. This study examines the effects of this delisting on national health insurance expenditures for pharmaceuticals. An interrupted time series analysis was conducted for the period from January 2005 to August 2007 by using administrative claims from Korea's National Health Insurance. The main outcome variable was the total pharmaceutical expenditure measured as a whole and based on the level of health care institutions and therapeutic classes. Comparison between exposure group (delisted drugs) and non-exposure group (listed drugs) were done. No changes in the level of or trend in the total pharmaceutical expenditure were detected. However, the delisting reduced pharmaceutical expenditures in clinics. Delisting effects were also observed according to therapeutic classes of drugs. The results indicate that any delisting should take into account the type of drug.

Do Physicians Change Prescription Practice in Response to Financial Incentives?

We assessed the impact on physician prescription behaviors of an outpatient prescription incentive program providing financial rewards to primary care physicians for saving prescription costs in South Korea. A 10% sample of clinics (N = 1,625) was randomly selected from all clinics in the National Health Insurance claims database for the years 2009-2012, and all claims with the primary diagnosis of peptic ulcer or gastro-esophageal reflux diseases were extracted from those clinics' data. A clinic-level random-effects model was used. After the program, clinics in general medicine showed a lower prescription rate (by 0.8 percentage points), lower number of medicines prescribed (by 0.02), lower prescription duration (by 0.15 days), and lower drug expenditure per claim (by 740 won). Small clinics on the <25th percentile of a regional sum of monthly drug expenditure had shorter prescription duration (by 0.76 days), while large clinics on the ≥75th percentile and clinics in group practice had a higher prescription rate (by 1.5 and 2.5 percentage points, respectively) and a higher number of medicines prescribed (by 0.03 for group practice only) after the program. The outpatient prescription incentive program worked as intended only in certain subgroup clinics for the target medicines.