Impact of Optimal Medical Therapy at Discharge on One-year Direct Medical Costs in Patients with Acute Coronary Syndromes: A Retrospective, Observational Database Analysis in China

Use of secondary prevention medications in metropolitan and non-metropolitan areas: an analysis of 41,925 myocardial infarctions in Australia

BACKGROUND

People in remote areas may have more difficulty accessing healthcare following myocardial infarction (MI) than people in metropolitan areas. We determined whether remoteness was associated with initial and 12-month use of secondary prevention medications following MI in Victoria, Australia.

METHOD

We included all people alive at least 90 days post-discharge following MI between July 2012 and June 2017 in Victoria, Australia (n=41,925). We investigated dispensing of P2Y12 inhibitors (P2Y12i), statins, ACE-inhibitors or angiotensin receptor blockers (ACEI/ARBs), and beta-blockers within 90 days post-discharge. We estimated 12-month medication use using proportion of days covered (PDC). Remoteness was determined using the Accessibility/Remoteness Index of Australia (ARIA). Data were analyzed using adjusted parametric regression models stratified by STEMI and NSTEMI.

RESULTS

There were 10,819 STEMI admissions and 31,106 NSTEMI admissions. Following adjustment across NSTEMI and STEMI, there were no medication classes dispensed in the 90-days post-discharge that differed in a clinically significant way from the least remote (ARIA=0) to the most remote (ARIA=4.8) areas. The largest difference for NSTEMI were ACEi/ARB, with 71%(95%CI 70-72%) versus 80%(76%-83%). For STEMI, it was statins with 89%(88-90%) versus 95%(91-97%). Predicted PDC for STEMI and NSTEMI were not clinically significant across remoteness, with the largest difference in NSTEMI being P2Y12i with 48%(47-50%) versus 55%(51-59%), and in STEMI it was ACEi/ARB with 68%(67-69%) versus 76%(70-80%).

CONCLUSION

Remoteness does not appear to be a clinically significant driver for medication use following MI. Possible differences in cardiovascular outcomes in metropolitan and non-metropolitan areas are not likely to be explained by access to secondary prevention medications.

Cost-effectiveness analysis of screening for peripheral artery disease in patients with coronary artery disease in China: A Markov model

BACKGROUND

The innovative pharmacological combination of low-dose rivaroxaban plus aspirin provides clinicians with an ideal opportunity to intensify the medical treatment of patients with coronary artery disease (CAD) and comorbid peripheral artery disease (PAD). We aimed to determine the cost-effectiveness of PAD screening using the ankle-brachial index (ABI) test in patients with CAD (with rivaroxaban administered if the PAD screening was positive) compared with no-screening strategy in China.

METHODS

A Markov decision model using a 1-month cycle was developed to simulate the 25-year effectiveness and cost of PAD screening on 75-year-old patients with CAD in China, evaluating the quality-adjusted life years (QALYs) and incremental cost-effectiveness ratio (ICER). One-way, two-way, and probabilistic sensitivity analyses were conducted to assess the impact of variations in the key parameters for ICERs.

RESULTS

Our model found an incremental cost of RMB4,959 (US$740) and an incremental QALY of 0.054 after one-time ABI screening, leading to an ICER of RMB91,936 (US$13,717) per QALY gained over a 25-year period. The reduction in all-cause mortality related to rivaroxaban and its cost were the factors most affecting the ICER. The screening would become cost-effective by decreasing the monthly cost of rivaroxaban to RMB184.5 (US$27.5) or by using domestic-brand rivaroxaban according to the threshold of a willingness to pay RMB72,447 (US$10,809) per QALY gained.

CONCLUSIONS

Our study demonstrated that ABI screening for PAD to decide on low-dose rivaroxaban administration was not cost-effective for patients with CAD in China. Nevertheless, policy-guided cost changes for domestic-brand rivaroxaban could easily resolve this issue.

Generating Practice-Based Evidence in the Use of Guideline-Recommended Combination Therapy for Secondary Prevention of Acute Myocardial Infarction

Background: Clinical guidelines recommend beta-blockers, angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers, and statins for the secondary prevention of acute myocardial infarction (AMI). It is not clear whether variation in real-world practice reflects poor quality-of-care or a balance of outcome tradeoffs across patients. Methods: The study cohort included Medicare fee-for-service beneficiaries hospitalized 2007-2008 for AMI. Treatment within 30-days post-discharge was grouped into one of eight possible combinations for the three drug classes. Outcomes included one-year overall survival, one-year cardiovascular-event-free survival, and 90-day adverse events. Treatment effects were estimated using an Instrumental Variables (IV) approach with instruments based on measures of local-area practice style. Pre-specified data elements were abstracted from hospital medical records for a stratified, random sample to create "unmeasured confounders" (per claims data) and assess model assumptions. Results: Each drug combination was observed in the final sample (N = 124,695), with 35.7% having all three, and 13.5% having none. Higher rates of guideline-recommended treatment were associated with both better survival and more adverse events. Unmeasured confounders were not associated with instrumental variable values. Conclusions: The results from this study suggest that providers consider both treatment benefits and harms in patients with AMIs. The investigation of estimator assumptions support the validity of the estimates.

Real-World Data for Healthcare Research in China: Call for Actions

OBJECTIVES

This study aimed to provide an overview of major data sources in China that can be potentially used for epidemiology, health economics, and outcomes research; compare them with similar data sources in other countries; and discuss future directions of healthcare data development in China.

METHODS

The study was conducted in 2 phases. First, various data sources were identified through a targeted literature review and recommendations by experts. Second, an in-depth assessment was conducted to evaluate the strengths and limitations of administrative claims and electronic health record data, which were further compared with similar data sources in developed countries.

RESULTS

Secondary databases, including administrative claims and electronic health records, are the major types of real-world data in China. There are substantial variations in available data elements even within the same type of databases. Compared with similar databases in developed countries, the secondary databases in China have some general limitations such as variations in data quality, unclear data usage mechanism, and lack of longitudinal follow-up data. In contrast, the large sample size and the potential to collect additional data based on research needs present opportunities to further improve real-world data in China.

CONCLUSIONS

Although healthcare data have expanded substantially in China, high-quality real-world evidence that can be used to facilitate decision making remains limited in China. To support the generation of real-world evidence, 2 fundamental issues in existing databases need to be addressed-data access/sharing and data quality.

Current trends in optimal medical therapy after PCI and its influence on clinical outcomes in China

Background

Limited data were available on the current trends in optimal medical therapy (OMT) after PCI and its influence on clinical outcomes in China. We aimed to evaluate the utilization and impact of OMT on the main adverse cardiovascular and cerebrovascular events (MACCEs) in post-PCI patients and analyzed the factors predictive of OMT after discharge.

Methods

We collected data from 3812 individuals from 2016.10 to 2017.09 at TEDA International Cardiovascular Hospital. They were classified into an OMT group and a non-OMT group according to their OMT status, which was defined as the combination of dual antiplatelet therapy, statins, β-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers after PCI. Multivariable Cox regression models were developed to assess the association between OMT and MACCEs, defined as all-cause mortality, nonfatal myocardial infarction, stroke, and target vessel revascularization. A logistic regression model was established to analyze the factors predictive of OMT.

Results

Our results revealed that the proportion of patients receiving OMT and its component drugs decreased over time. A total of 36.0% of patients were still adherent to OMT at the end of follow-up. Binary logistic regression analysis revealed that baseline OMT (P < 0.001, OR = 52.868) was the strongest predictor of OMT after PCI. The Cox hazard model suggested that smoking after PCI was associated with the 1-year risk of MACCE (P = 0.001, HR = 2.060, 95% CI 1.346–3.151), while OMT (P = 0.001, HR = 0.486, 95% CI 0.312–0.756) was an independent protective factor against postoperative MACCEs.

Conclusions

There was still a gap between OMT utilization after PCI and the recommendations in the evidence-based guidelines. Sociodemographic and clinical factors influence the application of OMT. The management of OMT and smoking cessation after PCI should be emphasized.

A comparison of parametric propensity score-based methods for causal inference with multiple treatments and a binary outcome

We consider comparative effectiveness research (CER) from observational data with two or more treatments. In observational studies, the estimation of causal effects is prone to bias due to confounders related to both treatment and outcome. Methods based on propensity scores are routinely used to correct for such confounding biases. A large fraction of propensity score methods in the current literature consider the case of either two treatments or continuous outcome. There has been extensive literature with multiple treatment and binary outcome, but interest often lies in the intersection, for which the literature is still evolving. The contribution of this article is to focus on this intersection and compare across methods, some of which are fairly recent. We describe propensity-based methods when more than two treatments are being compared, and the outcome is binary. We assess the relative performance of these methods through a set of simulation studies. The methods are applied to assess the effect of four common therapies for castration-resistant advanced-stage prostate cancer. The data consist of medical and pharmacy claims from a large national private health insurance network, with the adverse outcome being admission to the emergency room within a short time window of treatment initiation.

Trends in optimal medical therapy at discharge and clinical outcomes in patients with acute coronary syndrome in Thailand

BACKGROUND

Optimal medical therapy (OMT) is recommended for patients with acute coronary syndrome (ACS) at discharge. This study aimed to assess temporal trends of OMT prescription as a five-drug regimen at discharge and its association with clinical outcomes in patients with ACS in Thailand.

METHODS

A retrospective cohort study was conducted in a tertiary-care medical center in Thailand. Data were collected from an electronic medical database. Patients were categorized into OMT or non-OMT groups based on their discharge medications. OMT was defined as a combination of aspirin and P2Y12 inhibitors, statins, beta-blockers, and angiotensin-converting enzyme inhibitors, or angiotensin receptor blockers. The primary outcome was 1-year all-cause mortality. The secondary outcome was major adverse cardiac events (MACE) which was defined as a composite of non-fatal myocardial infarction, non-fatal stroke, and all-cause mortality. The prescription trends were also estimated. A multivariate Cox's proportional hazard model was used to assess the association of OMT prescriptions at discharge with all-cause mortality and MACE.

RESULTS

A total of 3531 patients discharged with ACS [mean age, 69.5 (SD 12.4) years; 58.3% male] were identified. Only 42.6% were discharged with OMT. The rates of OMT prescriptions did not change over time. However, the prescription of OMT with high-intensity statin was significantly increased from 5.0% in 2013 to 38.3% in 2018 (p for trend <0.001). Multivariable analyses indicated that OMT significantly reduced all-cause mortality (adjusted HR: 0.77; 95%CI: 0.63-0.95; p=0.012) and MACE (adjusted HR 0.84; 95%CI: 0.71-0.99; p = 0.044). Subgroup analysis indicated that patients receiving OMT with high-intensity statins exhibited survival benefits (adjusted HR: 0.72; 95%CI: 0.56-0.92; p=0.008).

CONCLUSIONS

The five-drugs comprising OMT were associated with a reduction in all-cause mortality and MACE in patients with ACS. Nevertheless, OMT prescribing remains underused and could be enhanced in the real-world setting.

Association of severe hypoglycemia with all-cause mortality and complication risks among patients with type 2 diabetes mellitus in China

AIMS

To investigate the association of severe hypoglycemia (SH) with all-cause mortality and complication risks among Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

Cohort study and nested case-control studies were conducted based on medical insurance database 2008-2015. The incidence of outcomes or the exposure of previous SH was compared among matched patients, respectively. The association between SH and outcomes was investigated and validated by different models.

RESULTS

Among cohort study participants (mean age of 59.0 ± 11.2 years), SH was associated with higher risk of all-cause mortality (HR = 1.80, P < 0.001) and transient ischemic attacks (TIA, HR = 1.51, P < 0.001), while no association was observed between SH and complications including myocardial infarction (MI), angina, arrhythmia and stroke. Similarly, SH was associated with about doubled all-cause mortality (OR = 1.76, P < 0.001) and TIA (OR = 2.00, P < 0.001), but not associated with risk of MI or stroke in nested case-control studies.

CONCLUSIONS

In Chinese patients with T2DM, SH is associated with increased risk of all-cause mortality and TIA, but no significant differences were found regard to the other examined complication risks, which need to be further explored in future studies.

Initiation And Persistence With Antiplatelet Agents Among The Patients With Acute Coronary Syndromes: A Retrospective, Observational Database Study In China

OBJECTIVES

To investigate the initiation and persistence of antiplatelet agents and the associated factors for patients with acute coronary syndromes (ACS) in Tianjin, China.

METHODS

Data were obtained from Tianjin Urban Employee Basic Medical Insurance database (2011-2015). Adult patients who were discharged alive after the first ACS-related hospitalization (index hospitalization) between January 2012 and December 2014 were included. Patients who initiated with antiplatelet therapy, including aspirin monotherapy, clopidogrel monotherapy, or dual antiplatelet with aspirin and clopidogrel at discharge or within the initial 30-day follow-up after discharge were further identified. Patients with no gaps of ≥30 days in antiplatelet therapy were deemed persistent. The logistic model and Cox model were used to explore the associated factors of initiation and persistence with antiplatelet agents, respectively.

RESULTS

In total, 21,450 patients (64.6±10.7 years; 46.0% female) were included. Only 70.3% (N=15,071) of them initiated with antiplatelet agents within the initial 30-day follow-up; 85.0% (N=12,809) of the initial users discontinued their antiplatelet therapy, and the average time to discontinuation was 117.4±119.7 days. The patients who had prior antiplatelet agents utilization (Odds ratio [95% CI]=1.93 [1.78-2.09]; hazard ratio [95% CI]=0.78 [0.74-0.81]), received percutaneous coronary intervention (PCI) during the baseline period (OR=1.47 [1.26-1.73]; HR=0.91 [0.84-0.97]) or index hospitalization (OR=22.40 [18.63-26.92]; HR=0.51 [0.49-0.53]) were more likely to initiate and persist with antiplatelet agents, while the female (OR=0.75 [0.70-0.81]; HR=1.22 [1.88-1.27]) patients were less likely to initiate and persist with antiplatelet agents.

CONCLUSION

The initiation and persistence with antiplatelet agents are poor among the ACS patients in Tianjin. Females are associated with poorer initiation and persistence, while prior antiplatelet agents use and receiving PCI during baseline period or index hospitalization are associated with better initial use and better persistence.