Efficacy of Influenza Vaccine among Elderly Patients by Physical Activity Status

Abstract

Objective: Although many studies have shown the usefulness of influenza vaccine in elderly in-patients, the efficacy of vaccination with regard to the daily physical activities of patients has not been fully evaluated. To address this issue, we correlated the use of medical resources with vaccination status in patients categorized according to their daily activity levels.Methods: The subjects comprised 237 in-patients at or above 51 years of age, who were hospitalized in the long-term care unit of a Japanese hospital between January and March, 1999. The vaccination status and medical resources use (i.e., oral antibiotics, injected antibiotics, blood cell count, chest X-ray) of each patient were recorded, and the patients were assigned to three subgroups, based on daily life activity scores.Results: Vaccinated in-patients in the 'bed-bound' category required fewer medical resources, i.e., oral antibiotics (-2.29 days, P<0.05), injected antibiotics (-5.02 days, P<0.001), blood cell counts (-4.66 times, P<0.001), and chest X-rays (-4.31 times, P<0.001), compared with unvaccinated in-patients. There were no significant differences in treatment parameters between vaccinated and unvaccinated patients in the 'partly limited' or 'no limitation' categories.Conclusions: It is suggested that influenza vaccination significantly reduces the need for medical treatment only among those in-patients who are the least physically active. Further studies are required to replicate these findings, and to elucidate the underlying reasons for this reduction.

Effect of vaccination on the use of antimicrobial agents: a systematic literature review

“…These studies are summarized in Table 3. In the study conducted by Hara et al in elderly patients hospitalized in the long-term care unit of a Japanese hospital, influenza vaccination reduced the number of days of parenteral antimicrobial use (66% reduction), but for oral antimicrobials the 44% reduction observed was non-significant when looking at the study population as a whole, with a more marked reduction in bedbound patients who can reasonably be assumed to be more frail [28]. Both studies of effectiveness of influenza vaccination in Hajj pilgrimsoriginating from Malaysia or Pakistan found significant reductions in antimicrobial use of 41% and 66% respectively [29,32].…”

“…The readout in the studies was varied, with antimicrobial use presented as number of antimicrobial prescriptions, courses or administration, number of days of oral antimicrobials, number of days of injected antimicrobials or whether patients had received antimicrobials. Four studies described antimicrobial use in children [17,23,27,34], one in mother-infant pairs and their household contacts [21], four in adults [28][29][30]32], one reported results from a population-level study comparing universal and targeted vaccination policies [31], and one in household contacts of vaccinated children [24].…”

“…Of the studies that reported on influenza vaccination and antimicrobial use in adults, one study from Japan described the number of antibiotic days in older individuals [28], two studies described antimicrobial use in adult pilgrims to the Hajj [29,32] and one study described antimicrobial use in U.S. students [30]. These studies are summarized in Table 3.…”