臺灣博碩士論文加值系統

背景與研究主題：阿司匹林(Aspirin) 是廣為人知可以有效減少心血管相關疾病風險的藥物。然而在急性缺血性腦中風，之前研究卻鮮少提及不同之初始阿司匹林治療劑量的效果比較。因此本研究主要欲比較不同初始劑量之阿司匹林對於急性缺血性中風病患的效用影響之比較。
研究方法：本研究採取回溯性研究設計，使用長庚醫院2008至2012年間中風病患的相關資料，並根據病患於急診時被給予阿司匹林初始劑量分成較高劑量組別(160-325 mg) 或較低劑量組(<160 mg)。由於兩組病患的基本屬性不同，本研究使用傾向分數相關的分析方式—包含配對(matching)，治療權重倒數機率(inverse probability of treatment weighting, IPTW)，以及模型中傾向分數來校正—的方式來平衡兩組差異並且使用多變數羅吉斯迴歸來評估不同劑量組別與病患預後的關聯性。 結果探討部分，主要預後結果(Primary outcome) 為較佳的神經學出院狀態(Favorable outcome on discharge)，定義為病患出院時改良Rankin量表評分≤1 (modified Rankin Scale mRS ≤1)。次要預後結果(Secondary outcome)為病患在住院期間死亡比例，住院期間中風惡化狀態—定義為出院時的美國國衛院腦中風評估表 (National Institute of Health Stroke Scale, NIHSS) 分數增加≥4分，以及住院期間發生出血事件的比例。
研究結果：本研究從7738個中風病患中，最後納入3802個病患進入分析。其中有750個病患(19.73 %)在較高劑量組，3052個病患(80.27 %)在較低劑量組。在初始負荷使用較高劑量的病患，出院時有顯著較好的神經學預後(more favorable on discharge, aOR 1.57, 95% CI 1.21-2.05)，但是在住院死亡，腦中風惡化，以及出血事件的發生率上，並無統計上顯著差異。
結論：急性缺血性中風病患，在阿司匹林初始負荷給予較高劑量(160-325 mg)可能對於病患有較佳的預後。

Background
Aspirin is known to reduce mortality and recurrent vascular events. However, there are no reported about the dose-response in treating acute ischemic stroke.
Objective: The objective of this study was to compare the effectiveness of different loading doses of aspirin in acute ischemic stroke.
Methods: This was a retrospective hospital-based cohort study from Chang Gung memorials hospitals in 2008 to 2012. Patients were classified as high dose (160-325 mg) or low dose (<160 mg) based on the initial loading amount of aspirin at the emergency department. Using multivariable logistic regression in a propensity score matching cohort, we compare the risk of in-hospital mortality, stroke progression, favorable clinical outcome on discharge and bleeding events during hospitalization between different treatment groups.
Results: From a total of 7,738 available patients, 3,802 patients were included in the study. Among them, 750 patients were in the high-dose group. Patients taking higher loading dose had more favorable clinical outcome on discharge (aOR, 1.57, 95% CI 1.21-2.05), but the risk of mortality, stroke in progression, and bleeding events were not significant different.
Conclusions: A higher-loading dose of aspirin (160-325 mg) can be beneficial in treating acute ischemic stroke.

指導教授推薦書…………………………………………………………………
口試委員會審定書………………………………………………………………
誌謝………………………………………………………………………………. iii
中文摘要………………………………………………………………………… iv
英文摘要…………………………………………………………………………. v
Chapter 1 Introduction……………………………… ………………………..……….1
1.1 Background and motivations …………………………………………..……..1
1.2 Study aim and questions……………………………………………..………..1

Chapter 2 Method….……………………………………………………………..……2
2.1 Data collection and patient selection …………….………………...…….…..2
2.2 Study variables……………………..……………………………….………...2
2.3 Outcome variables………………………...…………………………..……...4
2.4 Statistical analyses………………………...…………………………..……...5

Chapter 3 Results…………………………….………………………………..……..10
3.1 Baseline characteristics …………….…………….………………...…….....10
3.2 Outcome events rates ……………..………………………………………...10
3.3 Outcome models……………………….....…………………………….…...11
3.4 Subgroup analyses and sensitivity analyses………………………...………11

Chapter 4 Discussion…………………………….…………………………………..13
4.1 Main finding and importance …………….…………….………...……....13
4.2 Compare with previous studies ………….……...……….………...……......13
4.3 Explanations of our findings ………….…………….………...………......13
4.4 Limitations ………….…………….………...……………………...…......15

Chapter 5 Conclusion……………………………………………………………..…16
References………….……………………………………………………………..…17
Tables ……….……………………………………………………………..………..22
Figures …………………………………………………………..…………………..29
Supplements ……………………………..…………………………………………..37


List of Tables
Table 1 Baseline characteristics Original dataset…….………………..……..…22
Table 2 Baseline characteristics, 1:2 Caliper matching…………………………24
Table 3 Events rate in associated outcomes…………..…...……………………26
Table 3-1 Events rate in original dataset……………………………...……26
Table 3-2 Events rate in matched dataset………………..…………………26
Table 4 Results of outcome models………...……………….…..………………27
Table 4-1 Original dataset…………………………..………………………27
Table 4-2 Matched dataset……………………...…..………………………28
 
List of Figures
Figure 1 Patient enrollment flow chart…….……………………...………….…29
Figure 2 Balance disnogsis after propensity score matching………………...…30
Figure 3 Favorable outcomes on discharge.…….……………………..….…….31
Figure 4 Mortality in stroke hospitalization….…………………………...….…32
Figure 5 Stroke in progression during hospitalization…………………….….…33
Figure 6 Bleeding events during stroke hospitalization….……………….….…34
Figure 7 Subgroup analysis in patients with or without prior antiplatelet use on favorable outcomes on discharge …………….…….…………………….….…35
 

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