Home › Research › Risk factors
Benefits of influenza vaccination for low-, intermediate-, and high-risk senior citizens
Nichol KL, Wuorenma J, von Sternberg T.. Archives of internal medicine, 1998-09-01
Topic: Risk, prevention and care in population studies
Background Vaccination rates for healthy senior citizens are lower than those for senior citizens with underlying medical conditions such as chronic heart or lung disease. Uncertainty about the benefits of influenza vaccination for healthy senior citizens may contribute to lower rates of utilization in this group. Objective To clarify the benefits of influenza vaccination among low-risk senior citizens while concurrently assessing the benefits for intermediate- and high-risk senior citizens. Methods All elderly members of a large health maintenance organization were included in each of 6 consecutive study cohorts. Subjects were grouped according to risk status: high risk (having heart or lung disease), intermediate risk (having diabetes, renal disease, stroke and/or dementia, or rheumatologic disease), and low risk. Outcomes were compared between vaccinated and unvaccinated subjects after controlling for baseline demographic and health characteristics. Results There were more than 20000 subjects in each of the 6 cohorts who provided 147551 person-periods of observation. The pooled vaccination rate was 60%. There were 101 619 person-periods of observation for low-risk subjects, 15 482 for intermediate-risk, and 30 450 for high-risk subjects. Vaccination over the 6 seasons was associated with an overall reduction of 39% for pneumonia hospitalizations (P or =.05). Conclusions This study confirms that healthy senior citizens as well as senior citizens with underlying medical conditions are at risk for the serious complications of influenza and benefit from vaccination. All individuals 65 years or older should be immunized with this vaccine.
Key findings
- Results There were more than 20000 subjects in each of the 6 cohorts who provided 147551 person-periods of observation.
- Vaccination over the 6 seasons was associated with an overall reduction of 39% for pneumonia hospitalizations (P or =.05).
Why it matters
This study of senior health plan members found that influenza vaccination over six seasons was linked to an overall 39% reduction in pneumonia hospitalizations. It is about flu vaccination and pneumonia, not about treating, curing or preventing Alzheimer's disease.
New to this subject? Start with our plain-English guide: Risk factors, ranked →
Study details
- Participants20,000
- Evidence strengthLow
How this study scored 51/100
Published in a peer-reviewed journal. Scored zero for study design, effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Archives of internal medicine) |
| Journal's citation record | 3 / 4 | Archives of Internal Medicine: journal h-index 462 (OpenAlex, 2026-10-29) |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 1998 — older than 20 years, still counted |
| Sample size | 4 / 4 | 20,000 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 485 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 16.2 citations a year over 30 year(s) since 1998 |
| Impact for its field and year | 4 / 6 | Cited 15.2× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 1 / 6 | Cited by 1 other studies in this library |
| Still being cited | 1 / 4 | Cited 4 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 1 / 4 | Last-listed author Thomas Von Sternberg: h-index 7 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | University of Minnesota: institution h-index 1,568 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 4 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 9738606) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 51 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
May need a subscription OpenAlex found no free copy of the full text (checked 6 Feb 1020), so the publisher may charge for it. The PubMed abstract is free.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
APA 7th
Nichol, K. L., Wuorenma, J., & von Sternberg, T. (1998). Benefits of influenza vaccination for low-, intermediate-, and high-risk senior citizens. Archives of internal medicine. https://doi.org/10.1001/archinte.158.16.1769
Vancouver
Nichol KL, Wuorenma J, von Sternberg T. Benefits of influenza vaccination for low-, intermediate-, and high-risk senior citizens. Archives of internal medicine. 1998. doi:10.1001/archinte.158.16.1769. PMID: 9738606.
BibTeX
@article{nichol1998-9738606,
author = {Nichol, K. L. and Wuorenma, J. and von Sternberg, T.},
title = {{Benefits of influenza vaccination for low-, intermediate-, and high-risk senior citizens}},
journal = {Archives of internal medicine},
year = {1998},
doi = {10.1001/archinte.158.16.1769},
pmid = {9738606},
url = {https://doi.org/10.1001/archinte.158.16.1769}
}
Later studies that cite this one
1 study in the alzhub library lists this one in its references.
Related studies in Risk factors
Also tagged “delirium”
858 studies in the library carry the topic tag “delirium”; these are this study's neighbours in a fixed, alphabetical-by-hash tour of them, not the closest in content. All 858 tagged studies.