Disability among US Army Veterans vaccinated against anthrax
ABSTRACT To protect troops against the use of anthrax as a biological weapon, the US Department of Defense began an anthrax vaccination program in 1998. 14 years after the inception of the vaccination program, there is no evidence suggesting vaccination against anthrax carries long-term health risks for Active Duty Soldiers.
To investigate the association between Anthrax Vaccine Adsorbed (AVA) received while on Active Duty and subsequent disability determined by the Veterans Benefits Administration.
Case-control study nested in the cohort of all Active Duty personnel known to have separated from the US Army between December 1, 1997 and December 31, 2005. Cases were ≥10% disabled, determined either by the Army prior to separation (N=5846) or by the Veterans Benefits Administration (VBA) after separation (N=148,934). Controls (N=937,705) separated from the Army without disability, and were not receiving pensions from the VBA as of April 2007. Data were from the Total Army Injury and Health Outcomes Database and the VBA Compensation and Pension and Benefits database.
Disability status (yes/no); for primary disability, percent disabled (≥10%, 20%, >20%) and type of disability.
Vaccination against anthrax was four times more likely among disabled Veterans with hostile fire pay records (HFP, a surrogate for deployment). Vaccinated Soldiers with HFP had lower odds of disability separation from the Army 0.89 (0.80, 0.98); there was no association between vaccine and receiving Army disability benefits among those without HFP (OR=1.05, CI: 0.96, 1.14). Vaccination was negatively associated with receiving VA disability benefits for those with HFP (OR=0.66, CI: 0.65, 0.67), but there was little or no association between vaccine and receipt of VA disability benefits for those without HFP (OR=0.95, CI: 0.93, 0.97).
Risk of disability separation from the Army and receipt of disability compensation from the VA were not increased in association with prior exposure to AVA. This study provides evidence that vaccination against anthrax is not associated with long term disability.
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ABSTRACT: Anthrax vaccine adsorbed (AVA) administered intramuscularly (IM) results in fewer adverse events (AEs) than subcutaneous (SQ) administration. Women experience more AEs than men. Antibody response, female hormones, race, and body mass index (BMI) may contribute to increased frequency of reported injection site AEs. We analyzed data from the CDC anthrax vaccine adsorbed human clinical trial. This double blind, randomized, placebo controlled trial enrolled 1563 participants and followed them through 8 injections (AVA or placebo) over a period of 42 months. For the trial's vaccinated cohort (n=1267), we used multivariable logistic regression to model the effects of study group (SQ or IM), sex, race, study site, BMI, age, and post-vaccination serum anti-PA IgG on occurrence of AEs of any severity grade. Also, in a women-only subset (n=227), we assessed effect of pre-vaccination serum progesterone level and menstrual phase on AEs. Participants who received SQ injections had significantly higher proportions of itching, redness, swelling, tenderness and warmth compared to the IM study group after adjusting for other risk factors. The proportions of redness, swelling, tenderness and warmth were all significantly lower in blacks vs. non-black participants. We found arm motion limitation, itching, pain, swelling and tenderness were more likely to occur in participants with the highest anti-PA IgG concentrations. In the SQ study group, redness and swelling were more common for obese participants compared to participants who were not overweight. Females had significantly higher proportions of all AEs compared to males. Menstrual phase was not associated with any AEs. Female and non-black participants had a higher proportion of AVA associated AEs and higher anti-PA IgG concentrations. Antibody responses to other vaccines may also vary by gender and race. Further studies may provide better understanding for higher proportions of AEs in women and non-black participants.Vaccine 04/2014; DOI:10.1016/j.vaccine.2014.04.025 · 3.49 Impact Factor