tetano
Editor, Senior Moderator
Vaccine. 2017 Apr 18. pii: S0264-410X(17)30444-9. doi: 10.1016/j.vaccine.2017.03.092. [Epub ahead of print]
[h=1]Efficacy and safety of high-dose influenza vaccine in elderly adults: A systematic review and meta-analysis.[/h] Wilkinson K[SUP]1[/SUP], Wei Y[SUP]2[/SUP], Szwajcer A[SUP]3[/SUP], Rabbani R[SUP]4[/SUP], Zarychanski R[SUP]5[/SUP], Abou-Setta AM[SUP]4[/SUP], Mahmud SM[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]INTRODUCTION:[/h] Older adults are prioritized for influenza vaccination but also have lowered antibody responses to the vaccine. Higher-doses of influenza antigen may increase immune response and thus be more effective. Our objectives were to compare the efficacy and safety of the high-dose influenza vaccine to the standard-dose influenza vaccine in the elderly (age>65).
[h=4]METHODS:[/h] Data sources: Randomized trials (RCTs) from Medline (Ovid), EMBASE (Ovid), Cochrane Library (Wiley), ClinicalTrials.gov, reference lists of relevant articles, and gray literature.
[h=4]STUDY SELECTION:[/h] Two reviewers independently identified RCTs comparing high-dose influenza vaccine (60μg of hemagglutinin per strain) to standard-dose influenza vaccine (15μg of hemagglutinin per strain) in adults over the age of 65years.
[h=4]DATA EXTRACTION:[/h] Two reviewers independently extracted trial-level data including population characteristics, interventions, outcomes, and funding sources. Risk of bias was assessed using the Cochrane Risk of Bias tool.
[h=4]RESULTS:[/h] We included seven eligible trials; all were categorized as having a low (n=3) or unclear (n=4) risk of bias. Patients receiving the high-dose vaccine had significantly less risk of developing laboratory-confirmed influenza infections (Relative Risk 0.76, 95%CI 0.65 to 0.90; I[SUP]2[/SUP] 0%, 2 trials, 41,141 patients). Post-vaccination geometric mean titres and seroprotection rates were also higher in high-dose vaccine recipients. There were no protocol-defined serious adverse events in the included trials in either group.
[h=4]CONCLUSIONS:[/h] In elderly adults, the high-dose influenza vaccine was well-tolerated, more immunogenic, and more efficacious in preventing influenza infections than the standard-dose vaccine. Further pragmatic trials are needed to determine if the higher efficacy translates into higher vaccine effectiveness in adults over the age of 65.
Copyright ? 2017 Elsevier Ltd. All rights reserved.
[h=4]KEYWORDS:[/h] High-dose; Influenza; Influenza vaccines; Meta-analysis; Randomized control trial; Systematic review
PMID: 28431815 DOI: 10.1016/j.vaccine.2017.03.092
[h=1]Efficacy and safety of high-dose influenza vaccine in elderly adults: A systematic review and meta-analysis.[/h] Wilkinson K[SUP]1[/SUP], Wei Y[SUP]2[/SUP], Szwajcer A[SUP]3[/SUP], Rabbani R[SUP]4[/SUP], Zarychanski R[SUP]5[/SUP], Abou-Setta AM[SUP]4[/SUP], Mahmud SM[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]INTRODUCTION:[/h] Older adults are prioritized for influenza vaccination but also have lowered antibody responses to the vaccine. Higher-doses of influenza antigen may increase immune response and thus be more effective. Our objectives were to compare the efficacy and safety of the high-dose influenza vaccine to the standard-dose influenza vaccine in the elderly (age>65).
[h=4]METHODS:[/h] Data sources: Randomized trials (RCTs) from Medline (Ovid), EMBASE (Ovid), Cochrane Library (Wiley), ClinicalTrials.gov, reference lists of relevant articles, and gray literature.
[h=4]STUDY SELECTION:[/h] Two reviewers independently identified RCTs comparing high-dose influenza vaccine (60μg of hemagglutinin per strain) to standard-dose influenza vaccine (15μg of hemagglutinin per strain) in adults over the age of 65years.
[h=4]DATA EXTRACTION:[/h] Two reviewers independently extracted trial-level data including population characteristics, interventions, outcomes, and funding sources. Risk of bias was assessed using the Cochrane Risk of Bias tool.
[h=4]RESULTS:[/h] We included seven eligible trials; all were categorized as having a low (n=3) or unclear (n=4) risk of bias. Patients receiving the high-dose vaccine had significantly less risk of developing laboratory-confirmed influenza infections (Relative Risk 0.76, 95%CI 0.65 to 0.90; I[SUP]2[/SUP] 0%, 2 trials, 41,141 patients). Post-vaccination geometric mean titres and seroprotection rates were also higher in high-dose vaccine recipients. There were no protocol-defined serious adverse events in the included trials in either group.
[h=4]CONCLUSIONS:[/h] In elderly adults, the high-dose influenza vaccine was well-tolerated, more immunogenic, and more efficacious in preventing influenza infections than the standard-dose vaccine. Further pragmatic trials are needed to determine if the higher efficacy translates into higher vaccine effectiveness in adults over the age of 65.
Copyright ? 2017 Elsevier Ltd. All rights reserved.
[h=4]KEYWORDS:[/h] High-dose; Influenza; Influenza vaccines; Meta-analysis; Randomized control trial; Systematic review
PMID: 28431815 DOI: 10.1016/j.vaccine.2017.03.092