研究背景:
至今心血管相關疾病仍為死亡的主因之一，因此對於預防此類疾病的發生已成為相當重要的課題。許多研究顯示statins類藥品不僅可有效降低血脂，更可用於預防心血管疾病的發生率。然而越來越多研究指出statins藥品順從性與預防心血管疾病發生之臨床療效具高度相關性，發現到低順從性者相對於高順從性者其死亡率可高出8%。其中影響服藥順從性的因素包含對於statins藥品的認知、其本身收入以及醫療人員與使用者之間的互動等等。就國內來說，statins屬於高價藥品，於健保支出中占有越來越大的比例，因此在國內全民健保制度下，患者使用statins的順從性如何?以及順從性與心血管疾病發生率的關係是值得加以探討的議題。
研究目的:
探討statins藥品持有率與預防心血管疾病之相關性
研究方法:
本研究之研究設計為回溯性世代研究，資料來源主要以2000~2004年健保資料庫，ATC/DDD system；研究對象針對2001年於醫學中心首次發生心血管相關疾病住院患者(index date)，且於出院後90天內處方statins者；以持有率做為順從性代表，持有率定義:持有率=(statins總處方天數/一年追蹤天數)x100%，持有率分為三等級80%:high，79~40%:medium，<40%:low，Endpoint則定義為再次發生心血管疾病而住院。
研究結果:
依照病患所發生心血管疾病分為冠心病組，以及缺血性中風組，各自計算病患一年藥品持有率，將病患分為三等級後各組病患依序為:冠心組，藥品持有率高者:1196人，藥品持有率中者:1170人，藥品持有率低者:1414人；中風組:藥品持有率高者:412人，藥品持有率中者:604人，藥品持有率低者:908人；而各組其心血管疾病再發生率依藥品持有率高至低為，冠心病組:22.91%，30.26%，29.68%；中風組:4.48%，14.22%，54.24%。將藥品持有率與心血管疾病再發生率做存活分析後發現，在冠心病組，其藥品持有率之風險比為1.038(P=0.6085)，校正後為1.011(P=0.8836)；中風組，其藥品持有率之風險比為1.411(P=0.0001)，校正後為1.423(P<0.0001)，進一步以迴歸分析探討各自不同程度藥品持有率與心血管疾病再住院率的關係。在冠心病組，相對於高藥品持有率病患，藥品持有率中病患其風險比為1.373(P=0.0437)，校正後風險比為1.326(P=0.0755)，藥品持有率低病患風險比為1.094(P=0.5677)，校正後風險比為1.05(P=0.7521)；而中風組，相對於高藥品持有率病患，藥品持有率中者其風險比為1.562(P=0.0526)，校正後風險比為1.552(P=0.0584)，藥品持有率低者風險比為2.130(P=0.0003)，校正後風險比2.131(P=0.0004)。
研究結論:
Statins類藥品可有效降低心血管疾病再次發生率，而藥品順從性卻又是決定藥品有效與否的關鍵，本研究以藥品持有率代表藥品順從性，進一步證實，在冠心病組中，隨著順從性的增加，心血管再發生率也越低，雖然並未達到統計學上差異；而中風組，藥品順從性對於心血管疾病再發生率有一定的重要性，且藥品順從性低者相對於藥品順從性高者，其風險比例又較高，因此，如何提高藥品順從性，可說是決定病患預後的一項重要關鍵。

Background:
Until now, cardiovascular disease is still one of the major causes of death. To prevent cardiovascular disease has become an important issue. Many studies have proved that statins can not only effectively control hyperlipidemia but also help to prevent cardiovascular disease. However more and more studies have shown that the adherence of statins and cardiovascular disease prevention is highly related. The mortality of patient with low compliance is higher by 8 % than that of patients with high compliance. There are a lot of factors which may affect compliance, including the knowledge about statins, income, and the interaction between health care provider and patients. In Taiwan, statins has accouted for large part of National Health Insurance expenditure. Therefore, it is important to investagate the association between adherence of statins and cardiovascular disease.
Objective:
To analyze the association between adherence of statins and cardiovascular disease.
Method:
Our study design is a retrospective cohort study. The data source is from National Health Insurance in 2000~2004. Our subjective is patients with first cardiovascular disease in medical center used statins in 90 days after discharge.Use medication possession ratio (MPR) to present adherence, the calculation of MPR: MPR= (statins prescribed days) /365 days (365days as followed duration)x100%, define >80% as high MPR, 79~40% as moderate MPR, and <40% as low MPR. The endpoint is the readmission of cardiovascular disease
Result:
After calculating the one year MPR, in CHD group, there were 1196 persons in high MPR group, 1170 persons in medium MPR group and 1414 persons in low MPR group. And in ischemia stroke group, there were 412 persons in high MPR group, 604 persons in medium MPR group and 908 persons in low MPR group. The event rate of each group were 22.91%，30.26%，29.68% in CHD group and 4.48%，14.22%，54.24% in ischemia group. Used survival analysis to analyse the relationship between adherence of statins and readmission rate of cardiovascular disease, the hazard ratio of MPR in CHD group was 1.038 (P=0.6085), after ajustment the hazard ratio was 1.011 (P=0.8836), and the hazard ratio of MPR in ischemia stroke group was 1.038 (P=0.6085), after ajustment the hazard ratio was 1.011(P=0.8836). Furthermore our study analysed the readmission risk of different MPR by logistic regression. In CHD group, the odds ratio of moderate MPR group, compared to high MPR group, was 1.373 (P=0.0437), after ajustment the hazzar ratio is 1.326(P=0.0755), and the odds ratio group in low MPR group is 1.094(P=0.5677), after ajustment the hazard ratio was 1.05 (P=0.7521). In ischemia stroke group, the odds ratio of moderate MPR group, compared to high MPR group, was 1.562 (P=0.0526), after ajustment the hazard ratio was 1.552 (P=0.0584), and the odds ratio group in low MPR group was 2.130 (P=0.0003), after ajustment the hazard ratio is 2.131 (P=0.0004).

Conclusion:
Statins can effectively prevent readmission of cardiovascular disease. And compliance is the key point of statins’ effect. No matter in CHD group or ischemia group, the worse the compliance, the higher the risk of cardiovascular disease.

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