Therapeutics
Review: Influenza vaccination reduces cardiovascular events in adults
Udell JA, Zawi R, Bhatt DL, et al. Association between influenza vaccination and cardiovascular outcomes in high-risk patients: a meta-analysis. JAMA. 2013;310:1711-20.
Clinical impact ratings: F ★★★★★★✩ C ★★★★★★✩ Question
more than control in the subgroup of patients with recent ACS (3 RCTs, n = 789; 10% vs 23%; relative risk reduction [RRR] 55%, 95% CI 37 to 68; number needed to treat [NNT] 8, CI 6 to 13) but not the subgroup with stable CAD (2 RCTs, n = 600, RRR 6%, CI −61 to 45).
What is the effect of influenza vaccination on cardiovascular (CV) events in adults?
Review scope Included studies compared experimental or commercially approved influenza vaccinations with placebo or no treatment (control) in ≥ 50 adults followed for 28 days to 1 year. Primary outcome was a composite of major adverse CV events (CV death or hospitalization for myocardial infarction, unstable angina, stroke, heart failure, or urgent coronary revascularization). Secondary outcomes included components of the composite outcome.
Conclusion Influenza vaccination reduced cardiovascular events in adults and in the subgroup of patients with a recent acute coronary syndrome. Source of funding: No external funding. For correspondence: Dr. J.A. Udell, Women’s College Hospital and Peter Munk Cardiac Centre at Toronto General Hospital, Toronto, ON, Canada. E-mail [email protected]. ■
Review methods MEDLINE, EMBASE/Excerpta Medica, and Cochrane Central Register of Controlled Trials (all to Aug 2013); reference lists; CV and infectious disease conference abstracts (2000 to 2013); and ClinicalTrials.gov were searched for randomized controlled trials (RCTs). 6 RCTs (n = 6735, mean age 67 y, 51% women, mean follow-up 8 mo) met selection criteria. 4 RCTs were efficacy trials in patients with cardiac disease, and 2 were safety trials. 3 RCTs had adequate randomization, 3 were double-blind, and 5 described patient attrition; 4 were rated as high quality and 2 as low or unclear quality. 1 unpublished RCT was included in a sensitivity analysis. Subgroup analyses were done for recent acute coronary syndrome (ACS) (within 1 y of randomization) or stable coronary artery disease (CAD).
Commentary Influenza immunization directly affects the incidence and severity of influenza infection, with substantial variability depending on the age, comorbid conditions, and immune function of persons being vaccinated (1). Udell and colleagues did a systematic review and meta-analysis of RCTs to assess the effect of influenza vaccine on CV events. Results of the review showed a reduction in composite CV events, with an absolute risk reduction (ARR) of 1.7% (5 published RCTs, NNT 58, CI 38 to 124). The effect of influenza vaccine was particularly notable for those with recent ACS, with an ARR of 13% (NNT 8, CI 6 to 13).
With the aging of the US population, incidence of CV disease is increasing. This raises questions in the context of the population Main results of this meta-analysis: mean age 67 years, 51% women, and 36% In the 5 published RCTs, influenza vaccination reduced CV events with cardiac history. How might the increasing use of statins, with more than control; sensitivity analysis including the unpublished pleiotropic effects, including antiinflammatory activity, alter the trial had similar results (Table). Vaccination reduced CV events effects of immunization? With universal recommendations for influenza vaccination for persons > 6 months of age, how Influenza vaccination vs placebo or no treatment (control) in adults* will herd or community immunity affect population levels of influenza activity? Finally, how will pneumococcal Outcomes Number of Weighted At a mean 8 mo studies (n) event rates vaccination affect the reduction in CV morbidity and Vaccine Control RRR (95% CI) NNT (CI) mortality resulting from influenza immunization? (2) The CV events† 5 (6469) 3.0% 4.7% 36% (14 to 52) 58 (38 to 124) meta-analysis by Udell and colleagues presents compelling evidence for the benefits of influenza immunization, parCV events‡ 6 (6735) 2.9% 4.6% 36% (16 to 51) 61 (43 to 137) ticularly in patients with recently diagnosed CV disease. CV mortality 6 (6735) 1.4% 1.7% 18% (−67 to 59) NS Myocardial infarction§ 6 (6735)
1.3%
1.3%
1% (−68 to 42)
NS
Unstable angina
6 (6735)
1.2%
1.5%
19% (−33 to 51)
NS
Stroke||
6 (6735)
0.3%
0.4%
34% (−47 to 70)
NS
Heart failure
6 (6735)
0.4%
0.5%
17% (−242 to 80)
NS
Revascularization¶
6 (6735)
0.4%
0.5%
16% (−138 to 71)
NS
*CV = cardiovascular; NS = not significant; other abbreviations defined in Glossary. Weighted event rates, RRR, NNT, and CI calculated from control event rates and risk ratios in article using a random-effects model. †Primary analysis of 5 published trials. ‡Sensitivity analysis of 5 published and 1 unpublished trial. §Fatal and nonfatal myocardial infarction.
Bruno Granwehr, MD University of Texas MD Anderson Cancer Center Houston, Texas, USA References 1. Centers for Disease Control and Prevention (CDC). Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices–United States, 2013-2014. MMWR Recomm Rep. 2013;62:1-43. 2. Hung IF, Leung AY, Chu DW, et al. Prevention of acute myocardial infarction and stroke among elderly persons by dual pneumococcal and influenza vaccination: a prospective cohort study. Clin Infect Dis. 2010;51:1007-16.
||Fatal and nonfatal stroke. ¶Urgent coronary revascularization.
JC2
© 2014 American College of Physicians
18 February 2014 | ACP Journal Club | Volume 160 • Number 4
Downloaded From: http://annals.org/pdfaccess.ashx?url=/data/journals/aim/929769/ by a NYU Medical Center Library User on 02/26/2017
Review: Influenza vaccination reduces cardiovascular events in adults
Udell JA, Zawi R, Bhatt DL, et al. Association between influenza vaccination and cardiovascular outcomes in high-risk patients: a meta-analysis. JAMA. 2013;310:1711-20.
Clinical impact ratings: F ★★★★★★✩ C ★★★★★★✩ Question
more than control in the subgroup of patients with recent ACS (3 RCTs, n = 789; 10% vs 23%; relative risk reduction [RRR] 55%, 95% CI 37 to 68; number needed to treat [NNT] 8, CI 6 to 13) but not the subgroup with stable CAD (2 RCTs, n = 600, RRR 6%, CI −61 to 45).
What is the effect of influenza vaccination on cardiovascular (CV) events in adults?
Review scope Included studies compared experimental or commercially approved influenza vaccinations with placebo or no treatment (control) in ≥ 50 adults followed for 28 days to 1 year. Primary outcome was a composite of major adverse CV events (CV death or hospitalization for myocardial infarction, unstable angina, stroke, heart failure, or urgent coronary revascularization). Secondary outcomes included components of the composite outcome.
Conclusion Influenza vaccination reduced cardiovascular events in adults and in the subgroup of patients with a recent acute coronary syndrome. Source of funding: No external funding. For correspondence: Dr. J.A. Udell, Women’s College Hospital and Peter Munk Cardiac Centre at Toronto General Hospital, Toronto, ON, Canada. E-mail [email protected]. ■
Review methods MEDLINE, EMBASE/Excerpta Medica, and Cochrane Central Register of Controlled Trials (all to Aug 2013); reference lists; CV and infectious disease conference abstracts (2000 to 2013); and ClinicalTrials.gov were searched for randomized controlled trials (RCTs). 6 RCTs (n = 6735, mean age 67 y, 51% women, mean follow-up 8 mo) met selection criteria. 4 RCTs were efficacy trials in patients with cardiac disease, and 2 were safety trials. 3 RCTs had adequate randomization, 3 were double-blind, and 5 described patient attrition; 4 were rated as high quality and 2 as low or unclear quality. 1 unpublished RCT was included in a sensitivity analysis. Subgroup analyses were done for recent acute coronary syndrome (ACS) (within 1 y of randomization) or stable coronary artery disease (CAD).
Commentary Influenza immunization directly affects the incidence and severity of influenza infection, with substantial variability depending on the age, comorbid conditions, and immune function of persons being vaccinated (1). Udell and colleagues did a systematic review and meta-analysis of RCTs to assess the effect of influenza vaccine on CV events. Results of the review showed a reduction in composite CV events, with an absolute risk reduction (ARR) of 1.7% (5 published RCTs, NNT 58, CI 38 to 124). The effect of influenza vaccine was particularly notable for those with recent ACS, with an ARR of 13% (NNT 8, CI 6 to 13).
With the aging of the US population, incidence of CV disease is increasing. This raises questions in the context of the population Main results of this meta-analysis: mean age 67 years, 51% women, and 36% In the 5 published RCTs, influenza vaccination reduced CV events with cardiac history. How might the increasing use of statins, with more than control; sensitivity analysis including the unpublished pleiotropic effects, including antiinflammatory activity, alter the trial had similar results (Table). Vaccination reduced CV events effects of immunization? With universal recommendations for influenza vaccination for persons > 6 months of age, how Influenza vaccination vs placebo or no treatment (control) in adults* will herd or community immunity affect population levels of influenza activity? Finally, how will pneumococcal Outcomes Number of Weighted At a mean 8 mo studies (n) event rates vaccination affect the reduction in CV morbidity and Vaccine Control RRR (95% CI) NNT (CI) mortality resulting from influenza immunization? (2) The CV events† 5 (6469) 3.0% 4.7% 36% (14 to 52) 58 (38 to 124) meta-analysis by Udell and colleagues presents compelling evidence for the benefits of influenza immunization, parCV events‡ 6 (6735) 2.9% 4.6% 36% (16 to 51) 61 (43 to 137) ticularly in patients with recently diagnosed CV disease. CV mortality 6 (6735) 1.4% 1.7% 18% (−67 to 59) NS Myocardial infarction§ 6 (6735)
1.3%
1.3%
1% (−68 to 42)
NS
Unstable angina
6 (6735)
1.2%
1.5%
19% (−33 to 51)
NS
Stroke||
6 (6735)
0.3%
0.4%
34% (−47 to 70)
NS
Heart failure
6 (6735)
0.4%
0.5%
17% (−242 to 80)
NS
Revascularization¶
6 (6735)
0.4%
0.5%
16% (−138 to 71)
NS
*CV = cardiovascular; NS = not significant; other abbreviations defined in Glossary. Weighted event rates, RRR, NNT, and CI calculated from control event rates and risk ratios in article using a random-effects model. †Primary analysis of 5 published trials. ‡Sensitivity analysis of 5 published and 1 unpublished trial. §Fatal and nonfatal myocardial infarction.
Bruno Granwehr, MD University of Texas MD Anderson Cancer Center Houston, Texas, USA References 1. Centers for Disease Control and Prevention (CDC). Prevention and control of seasonal influenza with vaccines. Recommendations of the Advisory Committee on Immunization Practices–United States, 2013-2014. MMWR Recomm Rep. 2013;62:1-43. 2. Hung IF, Leung AY, Chu DW, et al. Prevention of acute myocardial infarction and stroke among elderly persons by dual pneumococcal and influenza vaccination: a prospective cohort study. Clin Infect Dis. 2010;51:1007-16.
||Fatal and nonfatal stroke. ¶Urgent coronary revascularization.
JC2
© 2014 American College of Physicians
18 February 2014 | ACP Journal Club | Volume 160 • Number 4
Downloaded From: http://annals.org/pdfaccess.ashx?url=/data/journals/aim/929769/ by a NYU Medical Center Library User on 02/26/2017
