全民健保修訂降膽固醇藥物給付規定對心血管疾病預防之成本效果分析──以Statin藥物為例

Abstract

背景：心血管疾病（CVD）連續幾十年來為台灣十大死因之一，這不僅是一項重要的公共衛生議題，同時也對台灣醫療體系帶來沉重的經濟負擔，特別是在老年人口。研究已證實，Statin 類藥物能有效預防心血管疾病，為臨床上普遍使用的降膽固醇治療藥物。隨著CVD盛行率的快速成長，2013年台灣全民健康保險署修訂降膽固醇藥物給付規定，擴大降膽固醇藥物的用藥標準。因此，在政策修訂後，接受降膽固醇治療的患者和藥品支出將會大幅增加。 目的：本研究探討台灣全民健康保險修訂降膽固醇藥物給付規定後， statin 類降膽固醇治療的成本效果（cost-effectiveness） 。 方法：本研究使用馬可夫決策模型（Markov decision model），目標族群針對65歲以上之心血管疾病（心絞痛、心肌梗塞、中風）或糖尿病患者，且低密度膽固醇介於100-130 mg/dL 的新符合健保用藥族群。本研究採用台灣全民健康保險署觀點，醫療費用與健康結果採用3% 折現。模型使用參數取自台灣全民健保資料庫、statin 藥物大型臨床試驗與統合分析研究，與已發表文獻。研究結果以遞增成本效果比（incremental cost-effectiveness ratio, ICER）進行分析。 結果：心絞痛、心肌梗塞、中風與糖尿病患者，接受終身 statin 類降膽固醇治療的 ICER 分別為新台幣 91,739 元、121,356 元、131,694元與227,938 元。因此，以國際衛生組織建議之成本效果指標為閾值，statin 類降膽固醇治療具有成本效果。敏感度分析顯示，研究結果會受到研究時間水平影響；然而，整體而言，statin 類降膽固醇治療仍具有高度成本效果。 結論：以台灣全民健康保險觀點，台灣全民健康保險修訂降膽固醇藥物給付規定後， statin 類降膽固醇治療對於心血管疾病的預防，具有成本效果。本研究結果顯示，早期和長期持續接受statin 類降膽固醇治療，具有較佳的臨床效果和成本效果。

Background: In Taiwan, cardiovascular diseases (CVD) are the leading causes of death for over 10 years in succession, and it is a crucial health issue and additionally impose an heavy economic burden on health care systems, particularly among the older patients. Statin is commonly used in cholesterol-lowering therapy to prevent CVD. With the rapid growth of CVD prevalence, in 2013, Taiwan’s National Health Insurance (NHI) reimbursement criteria for cholesterol-lowering therapy was modified to expand the use of cholesterol-lowering medicine. The new policy would contribute to an increase in both the number of eligible patients and statin medicine expenditures considerably. Objective: This study aims to evaluate the benefits and the cost-effectiveness of statin therapy for the newly eligible patients over 65 years old with CVD or diabetes under the modified NHI reimbursement criteria for cholesterol-lowering therapy in 2013, and to provide the evidence-based information for future research and decision-makers in Taiwan. Methods: We designed a Markov model to evaluate the cost-effectiveness of statin therapy for a hypothetical 65-year-old cohort with LDL cholesterol levels of 100-130 mg/dL having a history of CVD (angina, MI, stroke) or type 2 diabetes in Taiwan. The model used a lifetime time horizon, Taiwan’s NHI healthcare payer perspective, and 3% discount rate for costs and health outcomes. Data sources for model parameters included Taiwan’s National Health Insurance Research Database (NHIRD), large clinical trials and meta-analyses for the statin treatment, and other published sources. Main outcomes were incremental costs per quality-adjusted life-year (QALY) gained. Results: In the base-case analysis, cost-effectiveness results for the lifetime statin therapy in patients with a history of angina, MI, stroke or diabetes was NT$ 91 739, NT$ 121 356, NT$ 131 694 and NT$ 227 938 per QALY gained, respectively. In the one-way sensitivity analysis, the disutility caused by daily medication use was found to have a moderate impact on the cost-effectiveness of statin treatment, particularly for diabetic patients. Cost-effectiveness results were sensitive to changes in time horizons modeled. In Monte Carlo probabilistic sensitivity analysis, there was always had a high likelihood of being highly cost-effective at the thresholds of NT$ 700 000. Conclusion: This economic evaluation from Taiwan’s NHI perspective demonstrates that under the modified NHI reimbursement criteria, statin therapy would be effective and highly cost-effective for prevention of CVD for the newly eligible patients over 65 years old with CVD or diabetes. Early intervention with statins has better effectiveness and cost-effectiveness results among CVD patients. Importantly, the time horizon of the models plays a significant role in the cost-effectiveness of statin treatment. This finding also raises the importance of early and continuing treatment for a longer duration to achieve the optimal benefit of the investment in statins.