隨著人口逐漸老齡化，韓國在2018年已進入老齡社會，面臨著對醫療保健和長期護理系統可持續性的財政和人力挑戰。我們需要可靠的證據來指導健康政策的決策，以便以效率和公正的方式分配有限的資源（可能是有效的預防）。與此同時，中風作為最常見的心血管疾病之一，已經在韓國的死因排行榜上名列前茅超過十年。
這項研究旨在調查南韓不同類型中風相關的終身得病風險、終身餘命（LE）、餘命損失和終身醫療費用，以及估算缺血性和出血性中風患者的健康餘命（生活品質調整後餘命, QALE）和QALE損失。此外，研究還檢視了中風後功能障礙的長期動態變化，並估計了不同功能障礙的終身結果。中風患者的存活功能是利用卡普蘭-邁爾法（Kaplan-Meier's method）估計的，然後通過一個滾動算法(rolling-over algorithm) 來推斷終身存活率。核平滑法（Kernel smoothing method）被用於估計每個時間點的平均生活品質和功能障礙比例。
研究數據包括來自韓國國民健康保險-國家樣本群體(NHIS-NSC)的13,994名中風患者，以及來自韓國健康面板(KHP)的超過400名中風患者。結果顯示，韓國的中風終身得病風險一直在下降，唯一的例外是女性的蛛網膜下出血。出血性中風的餘命損失高於缺血性中風（6–9.7比4.7）。出血性中風預計由韓國國民健康保險支付的終身醫療費用約為$71,406（美元）和患者需自付的部分負擔$14,921，而缺血性中風的患者的終身醫療費用為$50,551和部分負擔為$11,666。缺血性中風的QALE和QALE損失分別為10.8 QALYs (生活品質調整後人年)和6.1人年，而出血性中風的QALE和QALE損失則分別為14.0人年和9.0人年。出血性中風男性的QALE損失大於女性(p < 0.05)，而缺血性中風的差異在統計學上並無顯著意義。該研究還發現，中風診斷後，全體功能障礙需求隨時間增加，對於缺血性和出血性中風，洗澡顯示出最小的無失能餘命（DFLE）和最大的DFLE損失。
這些發現為評估中風的長期影響以及指導韓國的資源分配和政策制定提供了寶貴的洞見。通過使用允許直接終身估計的方法來量化韓國中風的健康影響，這些發現提供了最好的現實世界證據，對健康政策決策以及所有醫療服務（包括預防中風）的評估具有指導性。這是韓國第一次將中風的流行病學與其結果整合的研究，並且對於以QALY為共同單位的健康效益或結果有準確的終身估計。這將為韓國推進有效的中風預防措施，並可能緩解老齡化即將帶來的影響鋪平道路。

With the progressive aging of the population, Korea has entered the aged society in 2018, facing financial and manpower challenges to the sustainability of healthcare and long-term care systems. We are in need of credible evidence that can guide the health policy decisions toward the best way (possibly effective prevention) in allocating limited resources with efficiency and justice. Meanwhile, stroke has been one of the top three causes of death in Korea for over a decade.
This study aimed to investigate the lifetime risks, life expectancy (LE), loss-of-LE, and lifetime costs related to different subtypes of stroke in South Korea, as well as estimating the quality-adjusted life expectancy (QALE) and loss-of-QALE for ischemic and hemorrhagic stroke patients. Additionally, the study examined the long-term dynamic changes of functional disabilities and estimated lifetime outcomes of different functional disabilities after a stroke. The survival function of stroke patients was estimated by the Kaplan-Meier’s method, and then extrapolated to lifetime through a rolling-over algorithm. Kernel smoothing method was used to estimate the mean quality of life and proportion of functional disabilities at each time points.
The data included 13,994 stroke patients from the National Health Insurance Service-National Sample Cohort of Korea and over 400 stroke patients from the Korea Health Panel. Results revealed that the lifetime risks of stroke in Korea have been decreasing, with the exception of subarachnoid hemorrhage in females. The loss-of-LE is higher in hemorrhagic stroke than in ischemic stroke (6–9.7 vs. 4.7). Expected lifetime costs reimbursed by the NHIS would amount to about $71,406 accompanied with $14,921 copayment from the patients for hemorrhagic stroke, and $50,551 and $11,666 for patients with ischemic stroke. The QALE and loss-of-QALE for ischemic stroke were 10.8 and 6.1 QALYs (quality-adjusted life years), and 14.0 and 9.0 QALYs for hemorrhagic stroke. Loss-of-QALE was larger in men with hemorrhagic stroke than women (p < 0.05), while the difference for ischemic stroke was statistically insignificant. The study also found that overall functional disability needs increased over time after stroke diagnosis, with bathing showing the smallest DFLE and the largest loss-of-DFLE for both ischemic and hemorrhagic stroke.
These findings provide valuable insights for evaluating the long-term impact of stroke and guiding resource allocation and policy-making in South Korea. By quantifying health impacts of stroke in Korea with the method that allows direct lifetime estimation, they provide best available real-world evidence for health policy decisions and evaluation of all healthcare services, including prevention for stroke. This is the first study in Korea to integrate epidemiology of stroke with its outcome and has accurate estimation with a lifetime horizon for quantification of health benefit or outcome under the common unit of QALY. It will pave a way for promoting effective measures on prevention of stroke in Korea and possibly ameliorating coming effects of aging.

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