Hyun Soon Sohn

The Association between Polypharmacy and Dementia: A Nested Case-Control Study Based on a 12-Year Longitudinal Cohort Database in South Korea

Dementia is a major concern among growing chronic diseases in the aging society and its association with polypharmacy has not been adequately assessed. The objective of this study was to determine the association between polypharmacy and dementia through multiple statistical approaches. We conducted a nested case-control study for newly diagnosed dementia cases using the South Korean National Health Insurance Service sample cohort database (2002–2013, n = 1,025,340). Interactions between polypharmacy (an average use of ≥5 prescription drugs daily) and comorbidities or potentially inappropriate medications (PIMs) were tested. The odds ratios (ORs) for dementia were analyzed according to the presence of comorbidities, PIM uses, the average number of prescribed daily drugs, and significant interactions with polypharmacy using univariate and multiple logistic regression analyses. A higher prevalence of comorbidities, history of PIM use, higher PIM exposure, and higher proportion of polypharmacy were noted among cases than in controls. In the univariate analysis, the OR for dementia increased significantly with the increase in the number of prescribed drugs [1–<5 drugs: 1.72, 95% confidence interval (CI): 1.56–1.88; 5–<10 drugs: 2.64, 95% CI: 2.32–3.05; ≥10 drugs: 3.35, 95% CI: 2.38–4.71; <1 drug used as reference]. Polypharmacy was correlated with comorbidities and PIM use, and significant interactions were observed between polypharmacy and anticholinergics; H2-receptor antagonists; and comorbidities such as hypertension, peripheral or cerebrovascular disease, congestive heart failure, hemiplegia, diabetes, depression, all other mental disorders, chronic obstructive pulmonary disease, peptic ulcer disease, and chronic liver disease (p<0.001). In the multiple regression analysis, most cases exhibited increasing ORs for dementia with increasing polypharmacy levels. Moreover, the increase in OR was more evident in the absence of drugs or comorbidities that showed significant interactions with polypharmacy than in their presence. Polypharmacy increases the risk of PIM administration, and as some PIMs may have cognition-impairing effects, prolonged polypharmacy may result in dementia. Therefore, efforts are needed to limit or decrease the prescription of medications that have been associated with risk of dementia in the elderly.

Higher systemic antibiotic consumption in a population of South Korea (2008 - 2009).

This study was conducted to investigate overall systemic antibiotic consumption levels and specific patterns using standardized Anatomical Therapeutic Chemical/Defined Daily Dose (ATC/DDD) methodology. National Health Insurance claims data during 2008 and 2009 was used. Antibiotic prescription data was classified using the ATC system and converted into DDD. Consumption figures were presented as the number of DDD per 1,000 inhabitants per day (DID). Detailed information on indications and seasonal variations, age and institutional determinants on antibiotic consumption were also explored. Total consumption was slightly increased from 24.3 to 25.2 DID in 2009 compared to 2008. The most frequently prescribed antibiotic was amoxicillin/clavulanic acid (5.1 and 5.2 DID, in 2008 and 2009, respectively), followed by cefaclor (3.0 and 3.3 DID) and amoxicillin (3.3 and 3.2 DID). Respiratory system diseases were the main causes of antimicrobial prescription (47.3%) and acute forms of bronchitis, tonsillitis and sinusitis were the most common diseases. There were typical seasonal fluctuations with heightened winter peaks. Consumption figures under 5 years of age (41.6 and 43.3 DID) were even higher than figures in aged 65 - 80 (36.2 and 39.1 DID). Antibiotic consumption in South Korea remained high compared with other OECD countries. Efforts to increase prudent antibiotic use, especially for upper respiratory system infections and for younger children, should be made to decrease antibiotic use.

Prescribed drugs and polypharmacy in healthcare service users in South Korea: an analysis based on National Health Insurance Claims data.

OBJECTIVE This study was conducted to analyze and compare the exposure to individually prescribed drugs and the prevalence of polypharmacy according to age group and concomitant disease in South Korea. METHODS The use of prescribed drugs was evaluated according to average numbers of prescription drugs used daily during a year or month, using the Korean Health Insurance Claims Database, which is representative of over 90% of citizens, in 2010 and 2011. The use of prescribed drugs was also analyzed according to concomitant diseases and age. Polypharmacy was defined as the use of 5 or more drugs daily during a specific observation period, and proportions of polypharmacy users were calculated according to comorbidity and age group. RESULTS The annual average numbers of daily used prescription drugs in 2010 and 2011 were 0.3 (SD = 0.5), 0.4 (SD = 0.7), 1.2 (SD = 1.5), and 2.3 (SD = 2.0) for people aged < 20 years, 20-49 years, 50-64 years, and ≥ 65 years, respectively. Proportions of individuals demonstrating polypharmacy increased with age and were 9.5% and 44.1% for elderly individuals in the year- and month-based analyses, respectively. The annual average number of daily medications used increased by ~2 drugs in the concomitant disease group, and the higher mortality group used a higher number of prescribed drugs than the lower mortality group. CONCLUSIONS The results highlight the elevated burden of multi-medication in elderly patients, and the study found that prescribed drug use increased with age and the number of concomitant diseases.

Living arrangements, chronic diseases, and prescription drug expenditures among Korean elderly: vulnerability to potential medication underuse.

BackgroundInsufficient social security combined with family structure changes has resulted in a poverty of the elderly. The objective of this study was to examine an association of living arrangements of the elderly with chronic disease prevalence and prescription drug use.Methods2008 Korea Health Panel Survey (KHPS) data were used in this study. Information on living arrangements, socio-demographics, health behaviors, chronic disease prevalence and healthcare expenditures including out-of-pocket (OOP) prescription drug expenditures for elderly aged 65 or older were collected from self-reported diaries and receipts. OOP prescription drug expenditure as a total cost that subject paid to a pharmacy for prescription drugs was examined. Logistic regression was used to identify differences in major chronic disease prevalence by living arrangements. The association of living arrangements with prescription drug use was analyzed using generalized linear model with a log link and a gamma variance distribution.ResultsProportions of elderly living alone, elderly living with a spouse only, and elderly living with adults aged 20–64 were 14.5%, 48.3%, and 37.2%, respectively. Elderly living alone showed 2.43 odds ratio (OR) (95% confidence interval (CI) = 1.66-3.56) for having major chronic diseases prevalence compared to elderly living with adults. Despite a higher major chronic disease prevalence, elderly living alone showed lower OOP prescription drug expenditures (Cost Ratio = 0.80, 95% CI = 0.67-0.97) after adjusting for the number of major chronic diseases. Total OOP prescription drug expenditures were significantly lower in patients with a low income level versus high income level.ConclusionsEven though elderly living alone had a higher risk of chronic disease, they spent less on OOP prescription drug expenditures. Optimal drug use is important for elderly with chronic diseases to achieve good health outcomes and quality of life. Public health policies should be supplemented to optimize medical treatment for vulnerable elderly living alone.

Evidence supporting the need for considering the effects of smoking on drug disposition and effectiveness in medication practices: a systematic narrative review.

This study was conducted to provide a narrative overview of interactions between smoking and drug effectiveness/ pharmacokinetics. Database searches were performed to identify review articles published prior to March 10, 2013. Eligible articles reporting altered pharmacokinetic profiles, drug response, or adverse drug effects due to drug-smoking interactions were selected. Information on mechanism of action and clinical effects from the selected articles (n = 83) were summarized by therapeutic drug class. For cardiovascular drugs, smoking effects were variable. Smoking reduced aspirin response but increased clopidogrel response by increasing active metabolites. Warfarin, which has a narrow therapeutic range, required dosage adjustment in smokers due to its rapid clearance. Smoking is a risk factor for respiratory disease, leading to a lower response to corticosteroid and requiring increased doses or additional drugs. Higher doses of theophylline and some antipsychotics, which are mainly metabolized by CYP1A2, are required to reach an optimal plasma concentration in smokers. Smoking is also a risk factor for cancer, especially for lung cancer. Erlotinib or gefitinib are epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) for lung cancer and showed lower anticancer effects in smokers. This summary of the interactions between smoking and drug pharmacological properties will aid healthcare professionals in providing patients with appropriate drug therapies, and emphasizes the need for considering smoking status as a patient factor in the clinical setting.

Association of Parkinsonism or Parkinson Disease with Polypharmacy in the Year Preceding Diagnosis: A Nested Case–Control Study in South Korea

IntroductionPublished studies on the association between polypharmacy and parkinsonism or Parkinson disease are very limited.ObjectiveThe objective of this study was to investigate whether polypharmacy is associated with parkinsonism or Parkinson disease in elderly patients.MethodsFrom a South Korean national health insurance sample cohort database for 2002–2013, we matched parkinsonism cases (defined by diagnosis codes for parkinsonism/Parkinson disease) and Parkinson disease cases (patients who had records for both Parkinson disease diagnosis and anti-Parkinson disease drug prescriptions) with controls. Logistic regression analysis evaluated the associations of parkinsonism/Parkinson disease with polypharmacy (i.e., five or more prescribed daily drugs) during the year preceding parkinsonism/Parkinson disease diagnosis, medications potentially associated with parkinsonism, and comorbidity status (using the Charlson Comorbidity Index score and hospitalization records).ResultsThe study population included 6209 cases and 24,836 controls for parkinsonism and 1331 cases and 5324 controls for Parkinson disease. In univariate logistic regression, odds ratios for parkinsonism/Parkinson disease increased significantly with increased polypharmacy, medications potentially associated with parkinsonism, Charlson Comorbidity Index score, or prior hospitalizations. In multiple logistic regression, odds ratios for parkinsonism/Parkinson disease (adjusted for medications potentially associated with parkinsonism and comorbidities) also increased with increased polypharmacy. Odds ratios (95% confidence interval) for Parkinson disease were higher than those for parkinsonism with stronger statistical significance: 1.41 (1.28–1.55) and 2.17 (1.84–2.57) for parkinsonism and 2.87 (2.30–3.58) and 4.75 (3.39–6.66) for Parkinson disease for between five and ten prescribed daily drugs and ten or more drugs, respectively.ConclusionsPolypharmacy in the year preceding diagnosis may be associated with an increased risk for parkinsonism/Parkinson disease. Medications potentially associated with parkinsonism were assumed to increase the risk for parkinsonism/Parkinson disease, but more studies are required to confirm this relationship.

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.

Patient response to insurer-led intervention for medication adherence - a pilot study based on claims data in Korea.

OBJECTIVE This study was designed to investigate patient responses to a medication counseling intervention program piloted by the National Health Insurance Service (NHIS), the national health insurer in Korea, to improve medication management in patients with hypertension, hyperlipidemia, or diabetes. METHODS AND MATERIALS Interventions were conducted from July to September 2013 through direct mailing followed by two telephone-initiated counseling sessions for the medication discontinuation group (< 80% medication possession ratio (MPR) and ≥ 2 months of discontinuation) and the medication over-possession group (≥ 150% MPR). The telephone intervention was applied through two models: model 1 (counseling by NHIS staff only) and model 2 (counseling by NHIS staff with contract-based working pharmacists in community pharmacies). Multivariate logistic regression analysis was performed to identify factors affecting favorable responses of patients to the telephone-initiated intervention. Patient responses to the telephone-initiated intervention were evaluated by a counselor. RESULTS In all, 891 patients were counseledvia telephone. Patient responses to the telephone-initiated intervention were favorablein 57.6%, neutral in 17.4% and not favorable in 24.9% overall. Counseling by NHIS staff together with pharmacists (model 2) produced more favorable responses from patients than counseling by NHIS staff alone (model 1) (OR 2.73, 95% CI 1.97 - 3.77). CONCLUSION Our findings of favorable responses to interventions support a personalized approach by the NHIS to improve patient behavior for medication adherence.

What are the patient factors affecting repetitive use of injectable pain relievers in outpatient care settings

Targeting repeated injection users with education interventions aimed at highlighting the extent of their current use and increasing awareness of the oral preparation options may reduce unnecessary injection use. The aim of this retrospective observational study was to investigate the patient factors related to repeated use of injection formulation analgesics in patients with musculoskeletal disorders who were frequent users of ambulatory healthcare services. Population-based national health insurance claims data for the time period July 2011 - December 2011 were analyzed. Patients aged 18 - 80 years with a musculoskeletal disorder, attended ambulatory healthcare settings > 25 times, and were prescribed pain relievers such as non-steroidal anti-inflammatory drugs and narcotic analgesics in an oral formulation for ≥ 14 days or in an injection formulation ≥ 3 times during the study period were included in the study. There were 742,675 repeated systemic analgesic users, and 64.1% (n = 476,021) of these patients were injection users. The average use of injections per patient during the 6-month period was 8.3. Tramadol was the most frequently prescribed medication for injection, followed by diclofenac, piroxicam, and ketorolac. Statistical analyses showed significant correlations between prevalent injection formulation use and patient factors such as gender, age, area of residence, days of healthcare utilization, number of healthcare centers visited, type of healthcare center visited, total medical expenditure, and total out-of-pocket expenditure. These factors could possibly be used to determine the target population for educational interventions aimed at changing behavior relating to the preference for injectable formulations.