Statins類藥物降低心血管疾病靜脈栓塞風險
作者：Kristina Rebelo
出處：WebMD醫學新聞
November 10, 2009（加州聖地牙哥訊）－研究者們驚訝地發現，因心肌梗塞（MI）或中風住院的病患，接受高劑量statins類藥物治療，可以顯著地降低靜脈或是肺栓塞風險；他們在CHEST 2009美國胸腔醫學會年會上向與會聽眾發表這項研究發現。
這些研究發現由主要作者、賓州費城Albert Einstein醫學中心一位內科第三年住院醫師Danai Khemasuwan所發表。
Khemasuwan醫師在發表會後的訪談中向Medscape胸腔醫學表示，我對這些結果感到驚訝，因為statins類藥物是心肌梗塞和中風的預防措施之一，這個疾病發生在動脈循環，但這項證據顯示statins類藥物可能也會對靜脈循環疾病造成影響。
Khemasuwan醫師報告他與同事們針對有粥狀動脈硬化患者使用statins類藥物與其對發生靜脈栓塞（VTE）的影響進行評估。研究收納593位病患（52%男性，其中77%為非裔美人；平均年齡為67.8歲），這些病患因為MI或是缺血性中風住到他們的機構。在這組中，73%（433位）正在服用一種statins類藥物，而VTE整體發生率為13%（共77位）。
讓Khemasuwan醫師印象深刻的結果是，使用statins類藥物的病患，8.3%（433位中有36位）發生臨床VTE，沒有使用statins類藥物者則是26.3%（160位中有42位）（勝算比[OR]為0.25；95%信賴區間[CI]為0.16-0.42；P<0.001），這代表未使用的病患發生VTE的風險是使用statins類藥物者的三倍。
即使在控制典型VTE危險因子後，例如吸菸、癌症史、以及久躺等因素，使用statins類藥物發生血栓的風險下降（OR為0.27；95% CI為0.16-0.44；P<0.001）。
Khemasuwan醫師表示，我做了次組分析，結果顯示使用較高劑量的statins類藥物（每天超過40 mg）[OR為0.32；95%CI為0.12-0.82；P=0.017]，標準劑量[OR為0.48；95% CI為0.29-0.78；P=0.003]發生VTE的風險較低。
研究者也針對有癌症史病患進行研究，發現statins類藥物治療同樣也有避免VTE的作用。他並沒有要推測statins類藥物使用在其他高風險群的效果，例如外科病患，他承認這些需要做更多的研究。
在評論Khemasuwan醫師的研究時，ACCP總裁、德州休士頓Baylor醫學院胸腔/重症照護與睡眠部門主任及教授Kalpalatha Guntupalli醫師向Medscape胸腔醫學表示，靜脈栓塞每年在美國造成顯著發病、死亡事件以及龐大的醫療費用。雖然還需要更多的研究，但目前的研究證實statins類藥物有助於降低特定病患族群的VTE發生率。
這項研究並未接受商業贊助。Khemasuwan醫師與Guntupalli醫師表示已無資金上的往來。
Statins May Reduce Risk for Venous Thromboembolism in Patients With Cardiovascular Disease
By Kristina Rebelo
Medscape Medical News
November 10, 2009 (San Diego, California) — Investigators were surprised to find an apparent reduction in risk for venous or pulmonary thromboembolism in patients admitted to the hospital with myocardial infarction (MI) or stroke who were treated with high-dose statin therapy, they told attendees here at CHEST 2009: American College of Chest Physicians Annual Meeting.
The findings were presented by lead author Danai Khemasuwan, MD, a third-year resident in internal medicine at Albert Einstein Medical Center in Philadelphia, Pennsylvania.
"I was surprised at the outcome because statins are a preventive measure for myocardial infarction and stroke, which is disease in the arterial circulation, but this evidence shows that statins may affect the disease in the venous circulation as well," Dr. Khemasuwan told Medscape Pulmonary Medicine in an interview after his presentation.
Dr. Khemasuwan reported that he and his colleagues looked at the relation between the use of statins in patients with a history of atherosclerosis and its influence on the development of venous thromboembolism (VTE). This was a retrospective study of 593 patients (52% female; 77% African American; mean age, 67.8?years) who had been admitted to his institution for either an MI or ischemic stroke. Of this group, 73% (n?= 433) were taking a statin and had an overall occurrence of VTE of 13% (n?= 77).
The specific results that impressed Dr. Khemasuwan were that, among patients taking statins, 8.3% (36 of 433) developed a clinical VTE, compared with 26.3% (42 of 160) of those not taking a statin (odds ratio [OR], 0.25; 95% confidence interval [CI], 0.16?- 0.42; P?< .001), meaning that nonusers were 3 times more likely to develop VTE than users of statin therapy.
Even after controlling for typical VTE risk factors, such as smoking, history of cancer, and immobilization, statin use was associated with a decreased risk of developing a clot (OR, 0.27; 95% CI, 0.16?- 0.44; P?< .001].
"I did the subgroup analysis and showed that the patients on higher doses of statins (>40?mg/day) [OR, 0.32; 95% CI, 0.12?- 0.82; P?= .017] have an even smaller chance of developing VTE, compared with a standard dose [OR, 0.48; 95% CI, 0.29?- 0.78; P = .003]," said Dr. Khemasuwan.
The investigators also looked at patients with a history of cancer and found a similar protective effect against VTE with statin therapy. He said he didn't want to speculate on the efficacy of statins in other high-risk groups, such as surgical patients, but acknowledged that further investigation is warranted.
Commenting on Dr. Khemasuwan's study, ACCP president Kalpalatha Guntupalli, MD, FCCP, professor and chief of the Pulmonary/Critical Care and Sleep Section at the Baylor College of Medicine in Houston, Texas, told Medscape Pulmonary Medicine that "venous thromboembolism leads to significant morbidity, mortality, and hospital costs in Americans each year. Although more research is needed, statins may prove effective in helping to reduce the incidence of VTE in specific patient populations."
The study did not receive commercial support. Dr. Khemasuwan and Dr. Guntupalli have disclosed no relevant financial relationships.
CHEST 2009: American College of Chest Physicians Annual Meeting: Abstract 598. Presented November?3, 2009.
