Seasonal maintenance of influenza vaccine-induced antibody response in kidney transplant recipients.
OBJECTIVE
Although annual influenza vaccination is recommended for kidney transplant recipients, efficacy as reflected by serum antibody titers has not been well studied beyond 1 month in kidney transplant recipients.


METHODS
We performed a single-center prospective cohort study of 51 kidney transplant recipients and 102 healthy controls receiving the 2006-2007 influenza vaccine. Anti-hemagglutinin antibody titers to A/H1N1, A/H3N2, and B were measured before and 1 month after vaccination, and again at the end of influenza season. The primary outcome was the proportion of participants maintaining seroprotection (antibody titer ≥1:32) for the duration of the influenza season after influenza vaccination.


RESULTS
Median follow-up time was 175 and 155 days in the transplant and control groups, respectively. For types A/H1N1 and B, a similar high proportion of the transplant and control groups (88.5 and 81.6% vs. 83.7 and 74.2% for A/H1N1 and B, respectively) maintained seroprotection. For type A/H3N2, significantly less of the transplant group (66.7%) versus the control group (90%) maintained a protective influenza vaccine response (odds ratio 0.21, 95% confidence interval 0.07-0.64). This difference disappeared in adjusted analyses. Actual geometric mean titers decreased significantly within both groups (p < 0.001) but this did not differ between groups.


CONCLUSIONS
Once they have developed protective vaccine-induced antibody responses to influenza vaccine, kidney transplant recipients are able to maintain adequate protective levels of antibody compared with healthy controls.
Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, USA. kelly.birdwell@vanderbilt.edu
Kelly A
KA
Birdwell
Mine R
MR
Ikizler
Li
L
Wang
Daniel W
DW
Byrne
Edith C
EC
Sannella
Peter F
PF
Wright
T Alp
TA
Ikizler
D000293:Adolescent; D000328:Adult; D000368:Aged; D000917:Antibody Formation / Q000276:immunology*; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D053122:Influenza A Virus, H3N2 Subtype / Q000276:immunology; D009981:Influenza B virus / Q000276:immunology; D007252:Influenza Vaccines / Q000276:immunology*; D007251:Influenza, Human / Q000517:prevention & control; D016030:Kidney Transplantation / Q000009:adverse effects / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D051437:Renal Insufficiency / Q000150:complications / Q000628:therapy; D012621:Seasons; D013997:Time Factors
D007252:Influenza Vaccines