本帖最後由 goodcat1111 於 2009-6-19 02:47 編輯
作者：Caroline Helwick
出處：WebMD醫學新聞
June 1, 2009（義大利米蘭）－根據一項發表在世界腎臟醫學會、歐洲腎臟協會、歐洲透析與移植協會、國際腎臟醫學會聯合會議中，分析參與高血壓最佳治療（Hypertension Optimal Treatment，簡稱HOT）研究受試者的數據顯示，罹患慢性腎臟疾病（CKD）的高血壓患者，使用Aspirin降低重大心血管疾病風險的好處顯著高於出血風險，且事實上，所得到的好處可能比正常腎臟功能患者還要多。
主要研究者、澳洲雪梨喬治國際健康機構的Meg Jardine醫師表示，我們相信我們的研究結果是非常重要的。腎臟疾病病患發生心血管疾病的風險很高，但他們經常沒有接受抗血小板凝集藥物治療。
她指出，這是我們首次證實腎功能不全患者可以因為Aspirin治療而受益。雖然重大出血事件可能因此增加，但所得到的好處超過出血的風險。
【自廣大族群所得到的數據】
這項研究收納了18,597位受試者，年齡介於50至80歲，舒張壓介於100~115 mmHg，且試驗前腎絲球廓清率（GFR）為60 ml/min/1.73 m2以下，其中有536位病患數值低於45 ml/min/1.73 m2以下，這些受試者被隨機分派每天使用乙醯水楊酸（75 mg）或是安慰劑。
在整體HOT研究族群中，使用Aspirin顯著降低重大心血管事件達15%（P=0.03）、心肌梗塞機率下降36%（P=0.02）、重大出血風險上升80%（P<0.001）。
GFR低於45 ml/min/1.73 m2重大心血管事件率下降達66%（95%信賴區間[CI]為33%-83%）、GFR介於45~59 ml/min/1.73 m2的下降達15%（95% CI為17%-39%）、而GFR高於60 ml/min/1.73 m2的受試者則是9%（95% CI為9%-24%），P值為0.03，Jardine醫師在最新臨床研究座談會中發表這項數據。
GFR低於45 ml/min/1.73 m2的死亡率下降49%（95% CI為6%-73%）、GFR介於45~59 ml/min/1.73 m2的受試者下降11%（95% CI為31%-40%），P值為0.04；那些GFR高於60 ml/min/1.73 m2受試者的死亡率並沒有顯著下降。
Jardine醫師的結論是，這代表每1,000位GFR低於45 ml/min/1.73 m2的病患，使用Aspirin可以避免76件重大心血管事件、40件心肌梗塞事件與40件心血管死亡事件、還有54件死亡。但使用這個藥物會增加27件重大出血與11件輕微出血事件。
【出血機率增加但未達統計顯著水準】
使用Aspirin造成重大出血的風險達：
* GFR低於45 ml/min/1.73 m2的受試者為291%（95% CI為92%-927%）
* GFR介於45~59 ml/min/1.73 m2的受試者為171%（95% CI為74%-391%）
* GFR高於60 ml/min/1.73 m2的受試者為153%（95% CI為111%-210%）
她表示，但是組與組之間的差異並未達到統計上顯著水準（P=0.27），且絕對差異數字是很小的。因為出血事件太少，因此未達到統計上顯著差異。
接受Aspirin治療並未造成致死性重大出血，且在腎功能最差的那一組，僅有27件非致命性重大出血事件，而這是我們觀察到效果最好的一組。非致命性重大出血發生在4位GFR介於45~59 ml/min/1.73 m2的受試者，以及5位GFR高於60 ml/min/1.73 m2的受試者。
她附帶表示，每年GFR的變化是很小的，因此CKD惡化並未在任何一個腎功能分組影響到Aspirin療效。
Jardine醫師的結論是，我們的發現顯示，Aspirin應該更廣泛地使用於CKD高血壓病患，特別是那些出血風險較低的。
明尼阿波里斯市明尼蘇達大學醫學教授與美國腎臟數據系統心血管特別研究中心主任的Charles Herzog醫師表示，要適當地研究Aspirin對這些病患的好處，將會需要5,000至10,000位病患，就如同HOT研究一樣。他指出，國家腎臟基金會腎臟疾病預後品質行動建議使用Aspirin預防腎臟疾病患者發生心血管事件。
他表示，我主張並對這些病患處方Aspirin，且我相信除非他們有腸胃道出血病史，否則他們應該接受這樣的治療。
WCN 2009: Benefits of Aspirin Therapy Outweigh Bleeding Risks in Hypertensive Patients With Chronic Kidney Disease
By Caroline Helwick
Medscape Medical News
June 1, 2009 (Milan, Italy) — In a hypertensive population with chronic kidney disease (CKD), the benefit of aspirin therapy in reducing major cardiovascular events outweighs the risk for bleeding and, in fact, might be even greater than the benefit obtained by people with normal kidney function, according to an analysis of participants in the Hypertension Optimal Treatment (HOT) study, presented here at the World Congress of Nephrology, a Joint Meeting of the European Renal Association–European Dialysis and Transplant Association and the International Society of Nephrology.
"We believe our results are very important. Renal patients are at great risk for cardiovascular disease but they often do not receive antiplatelet therapy," said principal investigator Meg Jardine, MD, from The George Institute for International Health in Sydney, Australia.
"For the first time we are showing that patients with renal dysfunction derive benefit from aspirin treatment. Major bleeding events may be increased but they are outweighed by the substantial protective benefits," she said.
Results Shown in Very Large Population
The study involved 18,597 participants, aged 50 to 80 years, with diastolic blood pressure of 100 to 115?mm?Hg and a baseline glomerular filtration rate (GFR) of 60?mL/min per 1.73?m2 or less, including 536 patients with values less than 45?mL/min per 1.73?m2. Subjects were randomized to daily acetylsalicylic acid (75?mg) or placebo.
In the overall HOT population, the use of aspirin reduced major cardiovascular events by 15% (P?= .03), reduced myocardial infarction by 36% (P?= .02), and increased the risk for major bleeding by 80% (P?< .001).
The risk for major cardiovascular events was reduced by 66% (95% confidence interval [CI], 33% - 83%) in those with a baseline GFR of less than 45?mL/min per 1.73?m2, by 15% (95% CI, 17% - 39%) in those with a baseline GFR of 45 to 59?mL/min per 1.73?m2, and by 9% (95% CI, 9% - 24%) in those with a baseline GFR of 60?mL/min per 1.73?m2 or higher (P?= .03), Dr. Jardine reported at a late-breaking clinical-trials session.
Mortality was reduced by 49% (95% CI, 6% - 73%) in those with a baseline GFR of less than 45?mL/min per 1.73?m2 and by 11% (95% CI, 31% - 40%) in those with a baseline GFR of 45 to 59?mL/min per 1.73?m2 (P?= .04); there was no significant reduction in those with a baseline GFR of 60?mL/min per 1.73?m2 or higher.
"This means that for every 1000 persons with a GFR less than 45?mL/min per 1.73?m2, aspirin would prevent 76 major cardiovascular events, 40 myocardial infarctions, 40 strokes, 40 cardiovascular deaths, and 54 all-cause deaths," Dr. Jardine concluded, "and would cause 27 excess major bleeds and 11 minor bleeds."
Bleeding Increased but Not Statistically Significant
The risk for major bleeding events was increased with aspirin by:
291% (95% CI, 92% - 927%) for those with a baseline GFR of less than 45?mL/min per 1.73?m2
171% (95% CI, 74% - 391%) for those with a baseline GFR of 45 to 59?mL/min per 1.73?m2
153% (95% CI, 111% - 210%) for those with a baseline GFR of 60?mL/min per 1.73?m2 or higher.
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But the differences between these groups was not statistically significant (P?= .27), she noted, and the absolute numbers were small. "There were so few bleeding events [that] we could not find them statistically significant," she said.
There were no fatal major bleeds caused by aspirin therapy, and only 27 nonfatal major bleeds in the worst renal-function group, which saw the most benefit. Nonfatal major bleeds occurred in 4 patients with a GFR of 45 to 59?mL/min per 1.73?m2, and in 5 patients with a GFR of 60?mL/min per 1.73?m2 or higher.
"Annual changes in GFR were minor, therefore CKD progression was not affected by aspirin therapy in any GFR group," she added.
"Our findings suggest that aspirin should be used more widely in hypertensive people with CKD, particularly those at a lower risk of bleeding events," Dr. Jardine concluded.
Charles Herzog, MD, director of the Cardiovascular Special Studies Center of the US Renal Data System and professor of medicine at the University of Minnesota, Minneapolis, said that to properly study the benefit of aspirin in these patients, a trial of 5,000 to 10,000 patients would be required, which the HOT trial was. He pointed out that the National Kidney Foundation Kidney Disease Outcomes Quality Initiative recommendation is to use aspirin for cardiovascular protection in patients with renal disease.
"I do advocate and prescribe aspirin in these patients," he said, "and I believe that unless they have a history of gastrointestinal bleeding, they should be on this therapy."
World Congress of Nephrology 2009: A Joint Meeting of the European Renal Association–European Dialysis and Transplant Association (ERA-EDTA) and the International Society of Nephrology (ISN): Abstract 766. Presented May 25, 2009. |
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