利用全民健保資料庫分析類風濕性關節炎病患使用生物製劑前後之醫療費用差異

研究背景：類風濕性關節炎(Rheumatoid Arthritis, RA)為一種由自體免疫障礙引致免疫系統攻擊關節的長期慢性炎症。近年來，針對自體免疫疾病的生物製劑(Biologics)相繼問市，這些新藥的好處是療效遠大於傳統藥物，而且副作用遠低於傳統藥物，但是價格昂貴，目前健保只有條件的给付於較嚴重的類風濕性關節炎病患。由於生物製劑效果較傳統治療藥物好，有效改善病患生活品質以及控制病情，因此使用人數逐年增加，而每年費用相對急遽上升。雖然使用的劑量與費用因病患病情而異，但藥費對病患與健保資源而言卻是相當沉重的負擔。而台灣的免疫相關疾病盛行率與國外相近，但是相關的疾病成本估計則少見於台灣的研究，由於自體免疫疾病是一種無法復原的慢性疾病，其各項資源的耗用亦非常可觀。研究目的：本研究係探討類風濕性關節炎病患使用生物製劑前後與醫療費用之差異。研究方法：以研究對象於2007年1月1日至2010年6月30日觀察期間內第一次使用生物製劑且持有類風濕性關節炎重大傷病卡，並設病患第一次使用生物製劑日期為Index date。本研究之研究對象Index date算起六個月內治療稱為Baseline period，期間內研究對象必須符合目標劑量治療病患第一次使用生物製劑日期為Index date，往前、往後計算其一年(365天)之門診、住院以及急診之醫療費用，再依照主次診斷前三碼有無714，分成與類風濕性關節炎相關費用以及與類風濕性關節炎不相關費用。再利用Wilcoxon Signed Rank Test 分析，計算同一類風濕性關節炎病患使用生物製劑前後之就醫次數與醫療費用之差異。研究結果：本研究包括了2,425位類風溼性關節炎病患，有87%病患在使用生物製劑第一年後持續使用單一生物製劑，使用兩種生物製劑者和只有治療六個月各占9%和4%。討論：研究發現使用單一種TNF-α生物製劑確實能使類風濕性關節炎病患縮短急性住院日數，但其醫療費用、醫療結果及生活品質的改善情形，值得未來進一步探討。

關鍵字

類風濕性關節炎；生物製劑；全民健保資料庫；醫療利用

並列摘要

Objective: This study aims to examine the pattern of biological treatment and the medical costs for patients with rheumatoid arthritis (RA). Methods: A longitudinal dataset that includes the claims of service used by a cohort of RA patients from the Bureau of National Health Insurance was used for this study. The inclusion criteria for the study cases were patients who: 1) were holding the Catastrophic Illness Card with RA; 2) had the 1st line TNF-α antagonist treatments for at least 6 months; 3) were aged over 17. Treatment patterns were defined based on their TNF-α Antagonist within 12 months after the initial 6-month treatment period. Wilcoxon signed rank tests were performed to compare differences in service costs and service uses between the pre- and post-biological treatment periods. Results: In total, 2,425 patients were eligible for analysis. In the first year after TNF-α initial 6-month treatment, 94% remained using the same TNF-α antagonist, 3% had switched from one to another TNF-α antagonist, and 3% discontinued use of TNF-α antagonist. RA patients treated with TNF-α antagonist were significantly associated with reductions in emergency room visits (p < 0.001), hospital days (p < 0.01) and total medication costs (excluding biologics) (p < 0.01). However, total RA-related outpatient visits and overall medication costs went up significantly (p < 0.001). Reduction in services use was not significantly observed among patients who switched during their TNF-α antagonist treatment. Conclusions: RA with biological treatment was associated with reductions of service uses; however, overall service costs were compromised by costs incurred from increased utilization of outpatient service and TNF-α antagonist medication costs under the context of healthcare in Taiwan.