腦中風是全球死亡與早年夭折的主要原因之一，造成大多數患者嚴重的長期精神及身體殘疾。目前研究已經證實慢性疾病是導致腦中風的危險因素，但較少研究考量環境風險對腦中風疾病轉移歷程的影響。本研究母體為健康保險資料庫2000年至2010年期間被診斷為腦中風的10,627位患者，並採用多狀態半馬可夫鏈結合Cox比例風險模式來評估環境風險因素對腦中風患者的影響程度。透過多變量結果證明環境風險對腦中風轉移過程有顯著影響，並與先前研究採納的重要危險因子做總體分析，發現環境風險在模型中仍維持其重要性。此外，採用在半馬可夫的轉移分配參數建立預測模型並與其他演算法的預測模型做比對，結果顯示半馬可夫模型對腦中風轉移時間的預測具有最好的預測表現("R" ^"2" "=90%)" 。研究結論除了找尋重要環境因素與探討腦中風轉移歷程的危險函數變化之外，更進一步透過次族群分析找出對環境風險因素最敏感的族群與台灣的高風險地區。

Stroke is one of the leading causes of death and premature mortality worldwide. Most stroke cases lead to serious mental and physical disability. Chronic diseases are contributory risk factors for stroke. However, few studies considered the transfer time in stroke development associated with living environment. In this study, 10,627 stroke patients diagnosed from 2000 to 2010 in Taiwan were surveyed. A semi-Markovian process with Cox regression model was constructed to evaluate the influence of environmental risk factors on stroke. Multivariate analysis showed that certain environmental risk factors highly influence the transition of stroke from chronic disease and dementia. Compared with that in a previous study, the proposed model considering environmental risks, achieved high prediction performance, and outperformed other benchmark algorithms with a high R2 that approaches 90%. The model quantified the sojourn time in different states, such as from chronic to stroke and stroke to dementia. This study also highlighted the high-risk sub-populations of stroke patients in Taiwan.

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