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作者：Kristina Rebelo  
出處：WebMD醫學新聞

　　November 12, 2009（加州聖地牙哥訊）－根據一項發表於CHEST 2009：美國胸腔醫學會年會上的研究結果，Statin類藥物對於舒張性心衰竭（DHF）病患來說可能有負面作用。在運動時有呼吸困難、疲倦的DHF病患，我們需要調整他們的藥物劑量。
　　
　　主要研究者與發表者、來自波士頓東北大學健康專業學院物理治療部門老年學家暨臨床教授Lawrence P. Cahalin治療師回溯性地回顧139位心衰竭病患的病歷，以了解使用statin類藥物對舒張以及收縮功能不全心臟衰竭病患（SHF）病患肺部功能與運動耐受性的影響。
　　
　　未使用statin類藥物的78位病患（82%為DHF；55%為女性；平均年齡為55±14歲）與61位使用statin類藥物的病患進行比較（72%為DHF；34%為女性；平均年齡為64±11歲）。Cahalin博士指出，statin類藥物中最常被處方的是atorvastatin（Lipitor，輝瑞藥廠），有高達75%statin類藥物使用者使用此藥物。
　　
　　Cahalin博士報告，相較於非statin類藥物使用者，使用者其第一秒使力吐氣容積（FEV1）、使力肺活量、以及運動耐受性顯著較低（P<0.05）。
　　
　　他認為，如果病患正在使用statin類藥物，且開始出現呼吸急促或是疲倦症狀，可能是statin類藥物造成的。這代表需要更進一步的研究來檢驗其原因，若是statin類藥物造成的，可能的解決之道是停用該statin類藥物，換成其他statin類藥物，或是改用其他降血脂藥物。
　　
　　Cahalin博士在發表會後的訪談中向Medscape胸腔醫學表示，我們看到許多病患改用其他statin類藥物後情況似乎改變了，因為不是每種statin類藥物都一樣，也不是所有病患對statin類藥物都有相同的反應。我們可能必須找出一個對這些病患比較不會造成症狀，而且具有我們所想要的降低膽固醇作用的方法。
　　
　　Cahalin博士表示，罹患收縮功能不全心臟衰竭病患且使用statin類藥物的病患，肺功能與某些運動指標有改善。然而，我們發現，罹患舒張功能不全的病患，其肺功能是下降的且運動耐受性較差，因此，對舒張功能不全患者來說，statin類藥物對肺部與運動功能有相反的作用。
　　
　　針對DHF且使用statin類藥物病患進行的次組分析顯示，肺部功能低於DHF但未使用statin類藥物的病患，其中差異達12%（P<0.05）。DHF且使用statin類藥物的病患，最高瓦特數與最高氧氣攝取，低於DHF但未使用statin類藥物患者（分別低了16%與18%；P<0.05）。
　　
　　根據Cahalin博士表示，最顯著的發現是在運動耐受性部分。DHF且正在使用statin類藥物患者，處於有氧運動閥值時量測的做功輸出顯著較低（差異為47%；P<0.05）。SHF且正在使用statin類藥物與未使用患者差異並不顯著。
　　
　　他指出，statin類藥物對於這些SHF患者的多效性作用是有差異的，包括對改善內皮細胞功能的發炎反應。DHF患者且使用statin類藥物有肺部功能機械性上限制的趨勢，可能是因為呼吸肌虛弱，有時候statin類藥物可能是此類事件的原因。相較於那些正在使用statin類藥物的收縮心臟衰竭病患，我認為罹患舒張心臟衰竭的病患，在發炎反應部分並不是那麼顯著，且由於某些未知原因，statin類藥物顯然會惡化這些病患的肌肉功能。
　　
　　發炎是SHF主要的問題，statin類藥物似乎對於SHF病患有益，這是為什麼在我的研究中，我相信罹患收縮功能不全心臟衰竭患者會受益於statin類藥物的原因。
　　
　　基於在某些病患身上的發現，研究者們告訴與會者，SHF與DHF患者使用statin類藥物的好處超過風險，且這些藥物已成為照護標準的一環。
　　
　　美國胸腔醫學會的理事長Kalpalatha Guntupalli醫師在一場記者會中評論這項研究。她表示，statin類藥物確實提供心血管疾病患者顯著好處；然而，就如同其他處方藥物，臨床醫師們應該對個別病患使用不同statin類藥物，並嚴密地監測效果。
　　
　　這項研究並未接受商業贊助。Cahalin博士與Guntupalli博士表示已無相關資金上的往來。


Statins Linked to Increased Dyspnea, Fatigue in Patients With Diastolic Heart Failure

By Kristina Rebelo
Medscape Medical News

November 12, 2009 (San Diego, California) — Statins might have negative effects in people with diastolic heart failure (DHF). Patients with DHF who experience increased dyspnea and fatigue during exercise might need to have their medications adjusted, according to a study released here at CHEST 2009: American College of Chest Physicians Annual Meeting.

Lead investigator and presenter Lawrence P. Cahalin, PT, PhD, gerontologist and clinical professor, Department of Physical Therapy, School of Health Professions, Northeastern University, in Boston, and colleagues there and at Massachusetts General Hospital in Boston, retrospectively reviewed the charts of 139 patients with heart failure, with the intention of looking at statin status and their effects on pulmonary function and exercise tolerance in patients with DHF and systolic heart failure (SHF).

A total of 78 patients not taking statins (82% with DHF; 55% women; mean age, 55 ± 14 years) were compared with 61 patients taking statins (72% with DHF; 34% women; mean age, 64 ± 11 years). Dr. Cahalin said that the most common statin prescribed was atorvastatin (Lipitor, Pfizer, Inc.), which is taken by 75% of statin users.

Dr. Cahalin reported that forced expiratory volume in the 1 second, forced vital capacity, and exercise tolerance were significantly lower in statin users than in nonusers (P < .05).

"I think that if a patient is on a statin and they start to report more shortness of breath or fatigue, it could possibly be due to the statin," he said. "It certainly suggests that further investigation is warranted to examine the cause and, if it is the statin, [a possible solution would be to] change to another statin or to another lipid-lowering agent altogether."

"I have seen people move from statin to statin and their symptoms seem to improve because not all statins are alike and not all patients react to statins alike," Dr. Cahalin told Medscape Pulmonary Medicine in an interview after his presentation. "It may be necessary to find one that produces fewer symptoms in these patients while also producing the favorable wanted effects of lowering cholesterol."

"Patients with systolic heart failure who were on a statin had improved pulmonary function and some exercise variables," said Dr. Cahalin, "However, in patients with diastolic heart failure, we found that there was a decrease in pulmonary function and poorer exercise tolerance — thus, [there is] an opposite effect of statins on pulmonary function and exercise in people with diastolic [and those with] systolic heart failure."

A subgroup analysis showed that pulmonary function measures in statin users with DHF were 12% lower than those in nonusers with DHF (P < .05). The peak Watts and peak oxygen uptake in statin users with DHF were lower than in nonusers with DHF (16% lower and 18% lower, respectively; P < .05).

The most significant findings, according to Dr. Cahalin, were in exercise tolerance. Measures of work output at the anaerobic threshold were lower in statin users with DHF than in nonusers with DHF (47% difference; P < .05). Differences between statin users and nonusers with SHF were not significant.

He pointed out that statins have a variety of pleiotropic effects in these SHF patients, including improvement of inflammation in endothelial function. "There was a trend toward a pulmonary mechanical limit in patients with DHF on a statin, which may be due to respiratory muscle weakness, something statins are known to cause. I think that patients with diastolic heart failure may have less of an inflammatory component and, for some unknown reason, statins appear to worsen the muscles in these patients compared with patients with systolic heart failure patients on a statin."

"Inflammation is a major problem in SHF. . . . Statins seem to be helpful in patients with SHF. . . and that is one of the reasons why, in my study, I believe, the patients with systolic heart failure benefited from the statin."

Despite the findings in some patients, the researchers told meeting attendees that the benefits of statins outweigh the risks in patients with both SHF and DHF, and that the drugs are an established standard of care.

Commenting on the study at the news conference was Kalpalatha Guntupalli, MD, FCCP, president of the American College of Chest Physicians. She said that "statins provide significant benefits for patients with cardiovascular disease. However, as for any new medication prescribed, clinicians should closely monitor the effects that different types of statins have on individual patients."

The study did not receive commercial support. Dr. Cahalin and Dr. Guntupalli have disclosed no relevant financial relationships.

CHEST 2009: American College of Chest Physicians Annual Meeting: Poster 592. Presented November 4, 2009.