tetano
Editor, Senior Moderator
Vaccine. 2015 Jul 26. pii: S0264-410X(15)00934-2. doi: 10.1016/j.vaccine.2015.07.006. [Epub ahead of print]
[h=1]Prevention of serious events in adults 65 years of age or older: A comparison between high-dose and standard-dose inactivated influenza vaccines.[/h] DiazGranados CA[SUP]1[/SUP], Robertson CA[SUP]2[/SUP], Talbot HK[SUP]3[/SUP], Landolfi V[SUP]2[/SUP], Dunning AJ[SUP]2[/SUP], Greenberg DP[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] A recent study showed that a high-dose inactivated influenza vaccine (IIV-HD) was 24.2% more efficacious than a standard-dose inactivated influenza vaccine (IIV-SD) in preventing laboratory-confirmed symptomatic influenza in adults ≥65 years. Here we evaluate the effectiveness of IIV-HD compared to IIV-SD in preventing serious illnesses considered potential sequelae or complications of influenza infection.
[h=4]METHODS:[/h] The original study was a double-blind, randomized, active-controlled, multicenter trial. Participants were adults ≥65 years randomized to receive IIV-HD or IIV-SD, and followed for 6-8 months post-vaccination for the occurrence of influenza and serious adverse events (SAEs). SAEs were events: leading to death or hospitalization (or its prolongation); considered life-threatening or medically important; or resulting in disability. For the present analysis, reported SAEs were classified as possibly related to influenza by three blinded physicians and rates per 1000 participant-seasons were calculated. Relative vaccine effectiveness (rVE) was estimated as (1-Rate Ratio)?100.
[h=4]RESULTS:[/h] 31,989 participants were enrolled, with 15,991 and 15,998 randomized to receive IIV-HD and IIV-SD, respectively. IIV-HD was significantly more effective than IIV-SD in preventing SAEs possibly related to influenza overall (rVE, 17.7%; 95% confidence interval [CI], 6.6-27.4%) and serious pneumonia (rVE, 39.8%; 95% CI, 19.3-55.1%). Borderline significance was observed for the efficacy of IIV-HD relative to IIV-SD for the prevention of all-cause hospitalizations (rVE, 6.9%; 95% CI, 0.5-12.8%).
[h=4]CONCLUSIONS:[/h] Compared to IIV-SD, IIV-HD reduced the risk of SAEs possibly related to influenza. The observed relative effectiveness against serious pneumonia is particularly noteworthy considering the burden of influenza and pneumonia in older adults.
Copyright ? 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
[h=4]KEYWORDS:[/h] Aged; Aged, 80 and over; Clinical trial, phase III; Influenza vaccines, human; Vaccines, inactivated
PMID: 26212007 [PubMed - as supplied by publisher] Free full text
[h=1]Prevention of serious events in adults 65 years of age or older: A comparison between high-dose and standard-dose inactivated influenza vaccines.[/h] DiazGranados CA[SUP]1[/SUP], Robertson CA[SUP]2[/SUP], Talbot HK[SUP]3[/SUP], Landolfi V[SUP]2[/SUP], Dunning AJ[SUP]2[/SUP], Greenberg DP[SUP]4[/SUP].
[h=3]Author information[/h]
[h=3]Abstract[/h] [h=4]BACKGROUND:[/h] A recent study showed that a high-dose inactivated influenza vaccine (IIV-HD) was 24.2% more efficacious than a standard-dose inactivated influenza vaccine (IIV-SD) in preventing laboratory-confirmed symptomatic influenza in adults ≥65 years. Here we evaluate the effectiveness of IIV-HD compared to IIV-SD in preventing serious illnesses considered potential sequelae or complications of influenza infection.
[h=4]METHODS:[/h] The original study was a double-blind, randomized, active-controlled, multicenter trial. Participants were adults ≥65 years randomized to receive IIV-HD or IIV-SD, and followed for 6-8 months post-vaccination for the occurrence of influenza and serious adverse events (SAEs). SAEs were events: leading to death or hospitalization (or its prolongation); considered life-threatening or medically important; or resulting in disability. For the present analysis, reported SAEs were classified as possibly related to influenza by three blinded physicians and rates per 1000 participant-seasons were calculated. Relative vaccine effectiveness (rVE) was estimated as (1-Rate Ratio)?100.
[h=4]RESULTS:[/h] 31,989 participants were enrolled, with 15,991 and 15,998 randomized to receive IIV-HD and IIV-SD, respectively. IIV-HD was significantly more effective than IIV-SD in preventing SAEs possibly related to influenza overall (rVE, 17.7%; 95% confidence interval [CI], 6.6-27.4%) and serious pneumonia (rVE, 39.8%; 95% CI, 19.3-55.1%). Borderline significance was observed for the efficacy of IIV-HD relative to IIV-SD for the prevention of all-cause hospitalizations (rVE, 6.9%; 95% CI, 0.5-12.8%).
[h=4]CONCLUSIONS:[/h] Compared to IIV-SD, IIV-HD reduced the risk of SAEs possibly related to influenza. The observed relative effectiveness against serious pneumonia is particularly noteworthy considering the burden of influenza and pneumonia in older adults.
Copyright ? 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
[h=4]KEYWORDS:[/h] Aged; Aged, 80 and over; Clinical trial, phase III; Influenza vaccines, human; Vaccines, inactivated
PMID: 26212007 [PubMed - as supplied by publisher] Free full text