Effect of Medication Usage on Immune Response to Inactivated
among Residents of a Virginia Life Care Facility, 1995-96
Background: It is widely recognized that the immune response to influenza vaccination
in the elderly may be influenced by medication usage. Previous studies point to
immunosuppresants, including steroids, as medications which hinder immune response
to influenza vaccination.
Objective: To determine if medication use is associated with the height and persistence
of immune response to influenza vaccination in the elderly.
Methods: In 1995, in a life care facility for the elderly in Virginia, 64 subjects received an
inactivated, trivalent influenza vaccine. In 1996, 68 subjects received a similar vaccine at
the same facility. The majority of subjects were self-sufficient and living in independent
apartments. Both vaccines contained A(H1N1), A(H3N2), and B components. Blood
sera samples were collected at the time of vaccination, and 1, 2, 3, 4, 12, 20, and 28
weeks post vaccination. Hemagglutination inhibition antibody titers were determined
from blood sera. A prospective cohort study design was employed. All of the subjects'
medications were categorized according to their medicinal purpose into four categories:
1) cardiac anti-hypertensives, 2) anti-inflammatory analgesics, 3) steroids, and 4)
bronchodilators. The outcomes of interest were seroprotection and seroconversion.
Kruskal-Wallis tests were used to examine HI antibody titers in users of specific
medication categories compared to non-users. Chi-square tests were used to examine
seroprotection and seroconversion in users compared to non-users. Logistic regression
was used to determine which predictors best explained seroprotection and
Results: In both vaccine years, subjects were mostly female, over 80 years old, possessed
a normal BMI, and had received influenza vaccine each of the previous five years. In
1995, at at least one point during the four weeks after vaccination, 67.2% were
seroprotected against A(H1N1), 43.8% against A(H3N2), and 68.8% against influenza B.
In 1996, at at least one point during the four weeks after vaccination, 72.1% were
seroprotected against A(H1N1), 44.1% against A(H3N2), and 77.9% against B. No
medications demonstrated a conclusive effect on seroprotection or seroconversion.
Conclusions: There was no clear evidence that any medication category examined led to a
consistent, discernible effect on immune response to the influenza vaccine.
Table of Contents
Table of Contents
Appendix I: Medication Categorization 57
Appendix II: Data Collection Form 60
Appendix III: Study Consent Agreement 64
Appendix IV: Example of Logistic Regression Procedure 67
About this Master's Thesis
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|Effect of Medication Usage on Immune Response to Inactivated Influenza Vaccine among Residents of a Virginia Life Care Facility, 1995-96 ()||2018-08-28 11:59:12 -0400||