Prevalence and predictors of premature discontinuation of dual antiplatelet therapy after drug-eluting stent implantation: importance of social factors in Asian patients

Prevalence and associated factors of premature discontinuation of antiplatelet therapy after ischemic stroke: a nationwide population-based study

BACKGROUND

We tried to evaluate the prevalence of premature discontinuation of antiplatelets and its affecting factors after ischemic stroke using large-sized representative national claims data.

METHODS

Patients aged 20 years or older with newly confirmed ischemic stroke who started aspirin or clopidogrel for the first time were selected from 2003 to 2010 National Health Insurance Service-National Sample Cohort (NHIS-NSC) of South Korea (n = 4621), a randomly collected sample which accounts for 2.2% (n = 1,017,468) of total population (n = 46,605,433). The prevalence of discontinuation of antiplatelets was measured every 6 months until the 24 months since the first prescription. Then we classified the participants into 2 groups according to the discontinuation status at 12 months and assessed the factors influencing premature discontinuation of antiplatelets within 12 months.

RESULTS

Among total participants, 35.5% (n = 1640) discontinued antiplatelets within 12 months and 58.5% (n = 2704) discontinued them within 24 months. The remaining 41.5% (n = 1917) continued them for 24 months or more. In the multivariate logistic regression analysis, initiating treatment with aspirin monotherapy [adjusted OR (aOR), 2.66, 95% CI 2.17-3.25] was the most prominent determinant of premature discontinuation within 12 months followed by CCI score ≥ 6 (aOR 1.50, 95% CI 1.31-1.98), and beginning treatment with clopidogrel monotherapy (aOR 1.41, 95% CI 1.15-1.72). Rural residency (aOR 1.36, 95% CI 1.14-1.62), < 4 total prescribed drugs (aOR 1.24, 95% CI 1.05-1.47), lower income (aOR 1.20, 95% CI 1.03-1.40 for middle income class and OR 1.21, 95% CI 1.02-1.45 for low income class), and ages ≥70 years (aOR 1.15, 95% CI 1.00-1.31) were also significantly associated with premature discontinuation of antiplatelets within 12 months.

CONCLUSIONS

The prevalence of premature discontinuation of antiplatelets after ischemic stroke was quite high. Thus, by understanding factors associated with premature discontinuation, a more strategic approach is required for the physicians to improve persistence with antiplatelets.

Clopidogrel-induced Pill Oesophagitis

Antiplatelet agents are routinely given to prevent thrombosis of coronary stents. Often this occurs during or immediately after the procedure, while the patient is still on the catheterisation laboratory table. Ingestion of pills while supine sometimes causes mild dysphagia and discomfort but, rarely, it can cause a more severe complication. We report a case of clopidogrel ingested during PCI, which caused chest pain and pill oesophagitis after the procedure. Conservative treatment was effective, symptoms resolved, and follow-up endoscopy showed resolution of the oesophageal inflammation.

Association between cognitive impairment and poor antihypertensive medication adherence in elderly hypertensive patients without dementia

Adherence to antihypertensive medication is a critical factor to control blood pressure and prevent complications. However, cognitive impairment can negatively affect medication adherence. In this study, we investigated the association between cognitive function and antihypertensive medication adherence among elderly hypertensive patients using the Korean National Health Insurance Service National Sample Cohort Data of the Elderly Cohort. The study included 20,071 elderly hypertensive patients and the prevalence of poor medication adherence to antihypertensive medications was 16.4%. A multivariate logistic regression analysis showed that lower cognitive function was associated with poor medication adherence (adjusted odds ratio 0.980, 95% confidence interval 0.961–0.999). Additionally, high income levels, living in metropolitan areas, and comorbidities (such as stroke, coronary heart disease, diabetes, and dyslipidemia) were positively associated with medication adherence, while patients diagnosed with cancers showed poor medication adherence. Our study demonstrated that cognitive impairment is a possible risk factor for poor antihypertensive medication adherence, even in patients without dementia. Thus, clinicians involved with geriatric care should monitor patients’ cognitive function and medication adherence. And if a patient shows cognitive impairment, clinicians need to educate patients and caregivers about the importance of proper adherence, and consider proper interventions to optimize the cognitive function of elderly patients.

Prevalence and Predictors of Early Discontinuation of Dual-Antiplatelet Therapy After Drug-Eluting Stent Implantation in Korean Population

The administration of antiplatelet drugs for months after a drug-eluting stent implantation is critical in decreasing the risk of complications, and premature discontinuation of antiplatelet therapy before the recommended period is the most important predictor for late complications. Therefore, we investigated the prevalence and associated factors of premature discontinuation of antiplatelet therapy in patients in Korea. This retrospective cohort study was conducted using the Korean National Health Insurance Service-National Sample Cohort data. Patients who were treated with dual-antiplatelet therapy (DAPT) were identified with medication prescription data. The Kaplan-Meier failure time plot was used to illustrate the cumulative probability of treatment discontinuation. Cox regression analysis was conducted to compare predictors of early discontinuation of DAPT. The characteristics of the early discontinuation group were not significantly different from the guideline concordance group, except for a higher prevalence of disability and a lower rate of chronic kidney disease. In a Cox regression model, the presence of hypertension was identified as a negative predictor of early discontinuation, and disability was not a statistically significant predictor. The prevalence of early discontinuation was 31.0% and seems to be significantly higher than those reported from prospective studies, which may more accurately reflect the real-world situation. In conclusion, physicians should make more effort to educate patients on the risk associated with premature discontinuation of antiplatelet therapy after percutaneous coronary intervention with drug-eluting stent, and further studies investigating the reasons for nonadherence of DAPT are needed to improve DAPT compliance.

Systematic reviews: causes of non-adherence to P2Y12 inhibitors in acute coronary syndromes and response to intervention

To understand the factors associated with non-adherence to oral antiplatelet (OAP) therapy in acute coronary syndromes (ACS), and where interventions have modified these factors. Linked systematic reviews were undertaken in accordance with the Preferred Reporting Items for Systematic reviews and Meta-analysis guidelines, using CINAHL Plus, MEDLINE, PsycINFO and PubMed databases. The searches were limited to studies available in English and published from 2000 onwards; last run in June 2015. Review 1: factors. Fifteen articles were identified that reported 25 different factors associated with OAP non-adherence. Factors were categorised into: Demographic, Treatment, Healthcare System Processes, Clinical, Opportunity (ie, factors outside the patients, such as cost and healthcare access) and Psychosocial. It was not possible to determine if any of these factors were more impactful than others, either overall or temporally. Review 2: interventions. Six articles were identified that described interventions targeting adherence in patients with acute coronary syndromes (ACS)/coronary artery disease (CAD). Four broad categories of intervention were identified: treatment counselling and education, educational materials, SMS reminders and telephone monitoring and reinforcement delivered different practitioners. Only reminder-based interventions had a consistently successful impact on adherence outcomes at both 3 and 12 months. A number of factors are associated with OAP non-adherence, and encouragingly, there is some evidence of the effectiveness of intervention to modify treatment adherence in patients with ACS/CAD. Future evaluations ensuring a better cohesion between the factors studied as associated with non-adherence and those targeted by intervention would further increase understanding and lead to improved results.

Adherence to dual antiplatelet therapy after coronary stenting: a systematic review

BACKGROUND

Adherence to dual antiplatelet therapy (DAPT) is critical after coronary stenting. Although adherence rates are frequently assessed in clinical trials, adherence rates in the unselected population recommended for treatment but beyond clinical trials are largely unknown. Therefore, we performed a systematic review of published observational studies to describe rates of DAPT adherence, trends in DAPT use over time, and patient-level factors associated with nonadherence.

HYPOTHESIS

DAPT adherence declines with increasing time after drug-eluting stent implantation.

METHODS

PubMed, Cumulative Index to Nursing and Allied Health Literature, Embase, and Web of Knowledge were searched through November 20, 2012 for studies including patients receiving 1 or more drug-eluting stents and reporting the use of aspirin and/or thienopyridines, or assessing factors associated with nonadherence to DAPT after bare metal or drug-eluting stent placement.

RESULTS

We included 34 studies in the description of DAPT adherence and 11 studies in the description of factors associated with nonadherence. Adherence to DAPT and thienopyridines was high at 1 month but declined by 12 months. Aspirin adherence was at least 90% throughout. Factors associated with nonadherence included bleeding, lower education level, immigrant status, and lack of education regarding DAPT.

CONCLUSIONS

DAPT adherence is suboptimal at 12 months, and interventions to increase adherence should focus on reducing bleeding risk and improving communication between patients and physicians.

Clopidogrel Therapy Discontinuation Following Drug Eluting Stent Implantation in Real World Practice in Israel

Background

Incidence and predictors of clopidogrel discontinuation after drug eluting stent (DES) implantation, in real world practice, are poorly known.

Methods

Prospective study included all patients who underwent implantation of at least one DES between February 2006 and January 2007. Predictors of clopidogrel discontinuation were assessed by a multivariable analysis.

Results

In 269 patients, mean period for clopidogrel therapy was 13.2 ± 7.2 month. Twenty eight patients (10.4%) discontinued clolopidogrel prematurely (< 3 months). Early clopidogrel discontinuation was a predictor of late stent thrombosis (P = 0.005) and urgent target vessel revascularization (P = 0.05). There was a trend for higher cardiac mortality among that group (P = 0.07). By 12 months, 173 patients (64.3%) have discontinued clopidogrel therapy. The most frequent circumstance to stop clopidogrel before 12 months was recommendation of family physician. Patients that were followed by cardiologist were more encouraged to longer clopidogrel therapy. In multivariable analysis being non Jew (OR 19.2, 95% CI 2.4 to 142, P = 0.005), not followed by cardiologist (OR 4.7, 95% CI 1 to 23.1, P = 0.05) and lack of information regarding the importance of clopidogrel maintenance at discharge from hospital (OR 10.8, 95% CI 2.7 to 42.9, P = 0.001) were independent predictors of early clopidogrel discontinuation.

Conclusions

Clopidogrel discontinuation, in real world practice is not unusual and related to poor outcome. Education for general physicians, clear instructions about the importance of antiplatelet maintenance at discharge and follow up by an expert cardiologist are opportunities to improve adherence do antiplatelet therapy following DES implantation.

Low mean corpuscular hemoglobin level is a predictor of discontinuation of antiplatelet therapy in patients with acute coronary syndrome

OBJECTIVE

Premature discontinuation of antiplatelet therapy (APT) increases the risk of thrombosis in patients who have undergone placement of a drug-eluting stent for acute coronary syndrome (ACS). The goal of the present study was to identify predictors of patients who would prematurely discontinue APT following stent implantation.

METHODS

One-hundred and sixty-one ACS patients who underwent percutaneous coronary intervention in our institution between November 2004 and September 2008 were enrolled in this study.

RESULTS

Over the 12-month follow-up period, 18 patients (11.2%) discontinued APT. Among baseline demographic and laboratory variables, multivariate analysis revealed that mean corpuscular hemoglobin (MCH) level was an independent risk factor for APT discontinuation (OR: 0.738, p=0.017). Kaplan-Meier survival analysis showed that the incidence of APT discontinuation was significantly higher in patients with low MCH (<30.0 pg) than in patients with high MCH (≥30.0 pg) (p=0.0006).

CONCLUSION

Low baseline MCH level was a predictor of APT discontinuation in ACS patients. Thus, careful consideration should be made before employing a drug-eluting stent in patients with low MCH levels.