台灣地區呼吸器依賴病人之發生率、生活品質、及成本效果研究

Incidence rates, quality of life and cost-effectiveness of patients under prolonged mechanical ventilation in Taiwan

洪美娟(Mei-Chuan Hung)

指導教授 ： 王榮德

國立臺灣大學/公共衛生學院/職業醫學與工業衛生研究所/博士(2012年)

https://doi.org/10.6342/NTU.2012.02952

摘要

研究目的：
本論文研究之主要目的為：(1)探討呼吸器依賴病人每年發生率 (incidence rates) 、共病 (co-morbidity) 聚集情形與預期壽命；(2)測量呼吸器依賴病人之生活品質: 病人、家屬及護理人員的比較；(3)估算呼吸器依賴病人之調整生活品質後的預期壽命 (quality-adjusted life expectancy, QALE)及調整生活品質後損失的預期壽命；(4) 估算呼吸器依賴病人之共病的遞增成本效用比值 (incremental cost-effectiveness ratio, ICER)。
研究背景：
公衛的核心價值是全體人類的健康，為達成此目標，國家必須有相對的配套措施。台灣很幸運的1995年3月全民健保實施，人民就醫機會逐漸均等不怕看病，並針對重大傷病族群予以免部份負擔，包括洗腎、呼吸器使用超過21天病人...等，使得人民不必因病而貧，目前已照顧到超過99%全體國人的健康。但也因此造成國家財政的重大負擔。依據中央健保局在2010年所公佈的重大傷病醫療費用前六大疾病，長期呼吸器依賴(呼吸器使用超過21天)的病人排名第二位，總支出每年約為新台幣170億。為同時顧及照護品質、效率及醫療資源的分配正義，以讓健保永續經營；我們必須開始思考不同的照護策略，包括先了解此類病人之發生率、生活品質、存活及成本效果。

長期呼吸器依賴(Prolonged mechanical ventilation or ventilator dependent) 發生背景：
由於全國加護病床有限，許多長期依賴呼吸器患者佔用急性病房或甚至加護病房，導致急症患者面臨一床難求。健保局多方考量下，於1998年提出「改善醫院急診重症醫療計畫」，訂定「急性呼吸治療病床」及「呼吸照護病床」之設置標準，2000年提出「全民健康保險呼吸器依賴患者整合性照護前瞻性支付方式」試辦計畫迄今這幾年來，此類病人雖然其增加的幅度藉由”整合性傳送服務”(Integrated delivery services)的介入自2005年後有延緩的趨勢，有關生命倫理公正性及成本效果的問題持續存在。這需要由中央健康保險局根據各種病人之存活與生活品質，與所有涉及此事的參與者(病人及其家屬、醫療照護人員與機構等)之共識，制定一套合乎醫學倫理之臨床指引來協助解決這個問題。目前國際間尚缺乏探討呼吸器依賴病人在不同共病下，結合存活、生活品質及醫療花費的成本效果 (cost-effectiveness)實證資料。
研究方法：
本論文研究以「以健保資料和對應之死亡檔登記資料所建立起的1998-2007年50,481筆呼吸器依賴案例全國代表性樣本長期追蹤資料庫」進行分析此類病人在不同疾病組合下之發生率及存活壽命；收集台灣北部醫學中心、中南部區域醫院，及其他呼吸治療醫院，使用EQ-5D歐盟生活品質問卷測量加護病房、呼吸照護中心、呼吸照護病房及居家照護之共142名呼吸器依賴病人的生活品質。並以嘉義基督教醫院1998-2007年間共有633名下轉至呼吸照護病房之呼吸器依賴病人，研究調整生活品質後的預期壽命及調整生活品質後損失的預期壽命。最後，結合50,481名病患之生病期間所有的醫療費用，計算其成本效果或生活品質調整後之人年(quality-adjusted life year, 簡稱QALY或健康人年)所負擔的費用。
結果與討論：
過去這10年來，呼吸器依賴病人成快速成長，每年約達兩萬人以上。其17-85歲累積發生率為0.103 - 0.145，也就是說17-85歲的人口族群中，如果沒有死於其他疾病，約有1/7至1/10的機會將成為呼吸器依賴病人，應及早採取對策。在預期壽命方面，退化性神經性疾病、中風或一般外傷之呼吸器依賴病人似乎比癌症或慢性腎衰竭病人有較長的存活壽命；小於85歲的慢性阻塞性肺部疾病(Chronic Obstructive Pulmonary Disease)相較其他年齡層共病，也有較長的存活(第一章)。
在病人生活品質評估方面，具中等認知功能 (MMSE≧15, Mini-mental status examination)的病人，由主要照顧家屬評值個案之生活品質，似乎較接近個案自評的結果；喪失認知及溝通能力的病人，由主要照護家屬或護理人員評值病人生活品質，則無明顯的差異 (第二章)。
平均年齡76歲的呼吸器依賴病人之預期壽命為1.95年，所損失的預期壽命的為8.48年。在調整生活品質後的預期壽命，具中等認知功能，為0.58健康人年；約60%喪失認知及溝通能力，為0.28-0.29健康人年。因呼吸器依賴而損失之調整生活品質後的預期壽命為9.87-10.17健康人年 ，顯示他們為極需醫療照護之健康弱勢族群(第三章)。
成本效果分析結果，認知功能差的病患，除肝硬化、一般外傷及小於64歲的菌血症或休克外，其每個健康人年均超過58,000元美金 (折合新台幣約1,798,00元)或3倍國內生產毛額(gross domestic product, GDP)；認知功能較佳，慢性腎衰竭、退化性神經性疾病或超過85歲的多重共病者亦是如此，似乎已超過世界衛生組織成本效果参考建議的每個健康人年約1-3倍GDP。但在肝硬化、一般外傷及小於65歲的共病患者，則少於1.4倍GDP。上述實證資料將可提供病人、家屬、醫療人員及醫療決策者在面臨病人是否接受長期呼吸插管決策，及資源分配之重要實證數據，並開啟彼此間的對話平台，最好及早預防走到此地步(第四章)。
結論：
整體而言，長期呼吸器依賴患者中某些特性病人之存活率、生活品質與成本效果不理想，值得作進一步更深入之分析探討，且在本國社會形成臨床決策之共識，以促進全民健保資源使用之公平性與效率。所有經呼吸治療救治超過21天仍需呼吸器維生者，除繼續進行呼吸器拔除訓練外 (weaning)，針對不可逆之無意識患者，請醫療團隊似可建議家屬，考慮轉為安寧療護以縮短病人痛苦。未來更應正視生命教育 (life education)，推廣在身體尚健康時，或疾病早期即簽署免予急救意願書DNR (Do not resuscitate) ，以對加護及呼吸治療資源作最適當之運用。

關鍵字

呼吸照護 ； 預期壽命 ； 發生率 ； 共病 ； 生活品質 ； 調整生活品後的預期壽命 ； 成本效果

並列摘要

Objective: The aims of our study are: (1) to determine the incidence rate (IR), median survival, life expectancies for different types or co-morbidities of patients undergoing prolonged mechanical ventilation (PMV) ; (2) to explore how much difference on the quality of life (QOL) assessments between patients under PMV and their proxies (family caregivers and nurses); (3) to estimate the quality-adjusted life expectancy (QALE) and the expected lifetime utility loss of different types of patients with PMV (4) and to estimate the incremental cost-effectiveness ratios (ICER) for different types of patients undergoing PMV.
Background: As we know, the core value of public health is health for all and the first step would be to achieve the goal of health care for all. In Taiwan, we are very fortunate to have developed the National Health Insurance (NHI) that implements a system of universal coverage (over 99% now) for all people of Taiwan. The NHI comprehensively covers various health care services, especially those of catastrophic illnesses, including maintenance hemodialysis for end stage renal disease and chronic ventilator use consecutively for more than 21 days, etc., which results in a tremendous financial burden and threatens the sustainability of the NHI. According to the reimbursement data of NHI in 2010, the prolonged mechanical ventilation (PMV) consumes the second highest in the average health expenditure with an annual total health expenditure of 17 billion NT (New Taiwan) dollars. In order to keep the sustainability of the NHI under good quality, efficiency and equitable distribution of resources at the same time, we began to think of different strategies. One of them is to explore the incidence rate, quality of life, survival, and cost effectiveness of the patients undergone prolonged mechanical ventilation. Although the increasing trend seems slowed down after the pilot implementation of IDS (integrated delivery service), the controversial issues of distributive justice on bioethics and cost-effectiveness of such cares still persist and may not be easily resolved without relevant information on the life expectancy and quality of life of different types of patients. To our knowledge, there has been few study that estimates the long term survival, quality of life, lifetime cost, and cost effectiveness together for PMV patients with multiple co-morbidities, which are the major goals of this dissertation.
Material and Methods: With the kind assistance from the National Health Research Institutes, we have just established a representative national longitudinal data of 50,481 cases who were ventilator dependent between 1998 and 2007. The data were linked with the reimbursement data of the NHI (National Health Insurance) and National Mortality Registration database of Taiwan. We used these databases of PMV to estimate IR, cumulative IR, and survival function, and quantitatively determine the QOL of patients using intensive care unit (ICU), RCC and RCW with the Taiwan version of EQ-5D questionnaire. Moreover, we applied latent class analysis (LCA) to re-classify these patients into several categories and determine their individual survival functions and extrapolated to 300 months in order to provide policy suggestions for proactive prevention. QOL measurements and lifetime survival functions were integrated together to calculate the quality-adjusted life expectancies for different types of PMV patients. Finally, we combined the data of lifetime health expenditures reimbursed by the NHI, and estimate the cost-effectiveness or incremental costs per quality-adjusted life year (QALY) according to different categories and/or clusters of diagnoses for these patients.
Results: The analysis of 50,481 PMV patients revealed that incidence rates increased as patients grew older and that cumulative incidence rates (17-85 years old) increased from 0.103 in 1998 to 0.183 in 2004 before stabilising thereafter. The life expectancies of PMV patients suffering from degenerative neurological diseases, stroke, or injuries tended to be longer than those with chronic renal failure or cancer. Patients with chronic obstructive pulmonary disease survived longer than did those co-morbid with other underlying diseases, especially septicaemia/shock (Chapter 1).
QOL assessments from family caregivers agreed more closely with patients than did those from nurses using EQ-5D evaluations for patients with clear cognition, but either proxy was acceptable for rating PMV patients with poor cognition (Chapter 2).
The average age of subjects was 76 years old. The life expectancy and loss of life expectancy were 1.95 years and 8.48 years, respectively. The QALE of 55 patients with partial cognitive ability and the ability to respond was 0.58 QALY, whereas the QALE of 87 patients with poor consciousness were 0.28 and 0.29 QALY for the EQ-5D measured by family caregivers and nurses, respectively. The loss of QALE for PMV patients was 9.87-10.17 QALY, corresponding to a health gap of 94-97% (Chapter 3).
The ICER for PMV varies greatly depending on different underlying causes and co-morbidities. Among these patients, maintenance treatments for PMV patients with poor cognition or patients more than 85 years of age might be the least cost-effective (Chapter 4).
Conclusion: Theses results of poor prognosis would provide stakeholders evidence for communication to facilitate clinical decisions. Moreover, the results can also serve as a starting point for a public dialogue on resource allocation of the NHI on critical care, aging and palliative care.

並列關鍵字

respiratory care ； life expectancy ； incidence rate ； co-nobilities ； quality of life ； quality-adjusted life expectancy ； cost-effectiveness

參考文獻

1.6 References

1. Needham DM, Bronskill SE, Sibbald WJ, Pronovost PJ, Laupacis A. Mechanical ventilation in Ontario, 1992-2000: incidence, survival, and hospital bed utilization of noncardiac surgery adult patients. Crit Care Med 2004; 32:1504-1509.

2. Carson SS, Cox CE, Holmes GM, Howard A, Carey TS. The changing epidemiology of mechanical ventilation: a population-based study. J Intensive Care Med 2006; 21:173-182.

3. Carson, S.S. Outcomes of prolonged mechanical ventilation. Curr Opin Crit Care 2006; 12(5), 405-411.

4. Cox CE, Carson SS, Holmes GM, Howard A, Carey TS. Increase in tracheotomy for prolonged mechanical ventilation in North Carolina, 1993-2002. Crit Care Med 2004; 32 (11), 2219-2226.