High-dose influenza vaccine for elderly: a closer look into the real-world data

Older adults are at increased risk of severe illness, hospitalization, and death due to influenza, making vaccination a key public health strategy. High-dose (HD) influenza vaccines have been recommended in several European countries to enhance protection in this vulnerable group. While clinical trials and observational studies have reported improved effectiveness of HD vaccines in preventing influenza-related outcomes, this advantage appears most consistent in individuals aged 75 and older. In contrast, evidence supporting the superiority of HD vaccines over standard-dose (SD) vaccines in the 65-74 age group (the "young-old") is limited and often not statistically significant. This review examined real-world effectiveness data comparing HD and SD influenza vaccines in elderly populations. While HD vaccines may provide added protection in the oldest age groups, especially against hospitalizations, SD vaccines continue to offer substantial and reliable protection, particularly in the 60-74 age range. Moreover, HD vaccines are associated with higher rates of mild side effects and carry a significantly greater cost, which may limit their cost-effectiveness for broad use in the younger elderly population. Given that the majority of elderly individuals in developed countries fall within the 65-74 age group, a tailored approach to vaccination may be more appropriate. Recommending HD vaccines primarily for those aged 75 and older, while offering SD vaccines to younger seniors, may help increase vaccine coverage without compromising protection. More real-world, age-stratified studies are needed to guide vaccination policies. Ultimately, any influenza vaccine is better than none, and SD vaccines remain an effective and accessible option for most older adults.