Monday, March 16, 2009
statins
from Heartwire — a professional news service of WebMD
February 20, 2008 — A study published this week provides a little more evidence that the benefit of statins extends beyond their ability to lower low-density lipoprotein (LDL) cholesterol levels [1]. In a new meta-analysis, investigators showed that the use of statins was significantly associated with a decreased risk of incidence or recurrence of atrial fibrillation (AF) in patients in sinus rhythm with a history of previous AF, those undergoing cardiac surgery, or those prescribed the drugs after an acute coronary syndrome (ACS).
In a paper published in the February 18, 2008 issue of the Journal of the American College of Cardiology, a special issue focusing on AF, Dr Laurent Fauchier (Centre Hospitalier Universitaire Trousseau, Tours, France) and colleagues note that the "beneficial effect seemed more marked in the prevention of AF recurrence than in primary prevention of AF" but cautioned against making too much of this finding as there was only a trend of benefit in these patients.
The meta-analysis included six studies with approximately 3500 patients in sinus rhythm. Three studies investigated the use of statins in patients with a history of paroxysmal AF or persistent AF undergoing electrical cardioversion, while the others investigated the use of statins in primary prevention of AF in patients undergoing cardiac surgery or following ACS. The follow-up in the six trials ranged from three to 26 weeks, and in five of the six studies, atorvastatin was the statin prescribed.
Treatment with a statin reduced the incidence and recurrence of AF 61% compared with placebo. While there were trends toward significance in primary- and secondary-prevention subset analyses, none of these reductions were statistically significant. The overall results were similar when investigators excluded the Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering (MIRACL) study, which was published only in abstract form. They note that the protective benefit of statins did not appear to be related to dose, as individual odds ratios were similar in the studies that used atorvastatin 40 mg and 80 mg to studies that used lower doses.
Effect of statins on the occurrence of AF
End point Odds ratio (95% CI)
All AF 0.39 (0.18 - 0.85)
Primary prevention of AF
(postoperative or new-onset AF) 0.60 (0.27 - 1.37)
AF recurrence 0.33 (0.10 - 1.03)
While the mechanisms of benefit are still unknown, Fauchier and colleagues note that statins reduce inflammation and that inflammation is involved in the "development, recurrence, and persistence of AF." They also note that some evidence suggests an association between AF and enhanced renin angiotensin system (RAS) activity. Other studies have also suggested a link between dyslipidemia and the RAS, and with statins reducing cholesterol levels, the drugs might downregulate the RAS and possibly explain the antiarrhythmic effects observed.
Still, large-scale, prospective, randomized clinical trials are needed to establish whether statins bring a similar benefit to those not part of the patient population in this meta-analysis and to explore whether the drugs might be an appropriate therapeutic option in all subgroups of patients for the management of AF, conclude the authors.
The study authors have disclosed no relevant financial relationships.
Source
1. Fauchier L, Pierre B, de Labriolle A, et al. Antiarrhythmic effect of statin therapy and atrial fibrillation. J Am Coll Cardiol. 2008;51:828-835.
The complete contents of Heartwire, a professional news service of WebMD, can be found at www.theheart.org, a Web site for cardiovascular healthcare professionals.
Clinical Context
AF is the most common arrhythmia, and patients undergoing coronary artery bypass graft (CABG) surgery are especially at risk for AF. A prospective, observational study by Mathew and colleagues, which appeared in the April 14, 2004, issue of the Journal of the American Medical Association, examined the incidence and risk factors for AF among 4657 patients undergoing CABG surgery. They found that 32.3% of study participants developed AF, and significant risk factors for AF included advanced age, a history of AF, chronic obstructive pulmonary disease, valvular surgery, and withdrawal of a beta-blocker or an angiotensin-converting enzyme (ACE) inhibitor after surgery. However, postoperative treatment with beta-blockers, ACE inhibitors, potassium supplementation, or nonsteroidal anti-inflammatory drugs reduced the risk for incident AF.
Some studies have suggested that statins might also reduce the risk for incident AF among high-risk individuals. The current meta-analysis addresses this issue.
February 20, 2008 — A study published this week provides a little more evidence that the benefit of statins extends beyond their ability to lower low-density lipoprotein (LDL) cholesterol levels [1]. In a new meta-analysis, investigators showed that the use of statins was significantly associated with a decreased risk of incidence or recurrence of atrial fibrillation (AF) in patients in sinus rhythm with a history of previous AF, those undergoing cardiac surgery, or those prescribed the drugs after an acute coronary syndrome (ACS).
In a paper published in the February 18, 2008 issue of the Journal of the American College of Cardiology, a special issue focusing on AF, Dr Laurent Fauchier (Centre Hospitalier Universitaire Trousseau, Tours, France) and colleagues note that the "beneficial effect seemed more marked in the prevention of AF recurrence than in primary prevention of AF" but cautioned against making too much of this finding as there was only a trend of benefit in these patients.
The meta-analysis included six studies with approximately 3500 patients in sinus rhythm. Three studies investigated the use of statins in patients with a history of paroxysmal AF or persistent AF undergoing electrical cardioversion, while the others investigated the use of statins in primary prevention of AF in patients undergoing cardiac surgery or following ACS. The follow-up in the six trials ranged from three to 26 weeks, and in five of the six studies, atorvastatin was the statin prescribed.
Treatment with a statin reduced the incidence and recurrence of AF 61% compared with placebo. While there were trends toward significance in primary- and secondary-prevention subset analyses, none of these reductions were statistically significant. The overall results were similar when investigators excluded the Myocardial Ischemia Reduction with Aggressive Cholesterol Lowering (MIRACL) study, which was published only in abstract form. They note that the protective benefit of statins did not appear to be related to dose, as individual odds ratios were similar in the studies that used atorvastatin 40 mg and 80 mg to studies that used lower doses.
Effect of statins on the occurrence of AF
End point Odds ratio (95% CI)
All AF 0.39 (0.18 - 0.85)
Primary prevention of AF
(postoperative or new-onset AF) 0.60 (0.27 - 1.37)
AF recurrence 0.33 (0.10 - 1.03)
While the mechanisms of benefit are still unknown, Fauchier and colleagues note that statins reduce inflammation and that inflammation is involved in the "development, recurrence, and persistence of AF." They also note that some evidence suggests an association between AF and enhanced renin angiotensin system (RAS) activity. Other studies have also suggested a link between dyslipidemia and the RAS, and with statins reducing cholesterol levels, the drugs might downregulate the RAS and possibly explain the antiarrhythmic effects observed.
Still, large-scale, prospective, randomized clinical trials are needed to establish whether statins bring a similar benefit to those not part of the patient population in this meta-analysis and to explore whether the drugs might be an appropriate therapeutic option in all subgroups of patients for the management of AF, conclude the authors.
The study authors have disclosed no relevant financial relationships.
Source
1. Fauchier L, Pierre B, de Labriolle A, et al. Antiarrhythmic effect of statin therapy and atrial fibrillation. J Am Coll Cardiol. 2008;51:828-835.
The complete contents of Heartwire, a professional news service of WebMD, can be found at www.theheart.org, a Web site for cardiovascular healthcare professionals.
Clinical Context
AF is the most common arrhythmia, and patients undergoing coronary artery bypass graft (CABG) surgery are especially at risk for AF. A prospective, observational study by Mathew and colleagues, which appeared in the April 14, 2004, issue of the Journal of the American Medical Association, examined the incidence and risk factors for AF among 4657 patients undergoing CABG surgery. They found that 32.3% of study participants developed AF, and significant risk factors for AF included advanced age, a history of AF, chronic obstructive pulmonary disease, valvular surgery, and withdrawal of a beta-blocker or an angiotensin-converting enzyme (ACE) inhibitor after surgery. However, postoperative treatment with beta-blockers, ACE inhibitors, potassium supplementation, or nonsteroidal anti-inflammatory drugs reduced the risk for incident AF.
Some studies have suggested that statins might also reduce the risk for incident AF among high-risk individuals. The current meta-analysis addresses this issue.
# posted by roodbont @ 4:17 PM 
