Meta-Analysis Suggests Influenza Vaccine Immunogenicity Significantly Decreased in SLE

SAN DIEGO, CA—Influenza vaccine immunogenicity is significantly decreased in patients with systemic lupus erythematosus (SLE) compared with healthy controls, a meta-analysis presented during the 2013 ACR/ARHP Annual Meeting has shown.

“Subgroup analysis suggests that decreased immunogenicity may be independent of immunosuppressive treatments,” noted Laurent Arnaud, MD, PhD, of Department of Internal Medicine, French Reference Center for SLE, Hôpital Pitié-Salpêtrière, AP-HP, UPMC and Université Pierre et Marie Curie, Univ Paris 06, Paris, France, and colleagues.

Therefore, specific vaccination schemes, such as the use of a second injection or the use of adjuvant vaccines, should be evaluated in this patient population, they recommended.

The investigators identified all studies from the MEDLINE, Cochrane and EMBASE databases published through February 2013 that compared immunogenicity of influenza vaccination in patients with SLE vs. healthy subjects.

“The immunogenicity was evaluated using the proportion of subjects with influenza antibody titers ≥1:40 (seroprotection rate) and the proportion of subjects with either a pre-vaccination hemagglutination-inhibiting titer <1:10 and a post-vaccination titer ≥1:40 or a pre-vaccination titer ≥1:10 and an increase in the titer by a factor of 4 or more (seroconversion rate),” Dr. Arnaud stated. “Pooled effect estimates were obtained using a random-effects model.”

Of 146 citations retrieved, 16 primary studies with 1010 patients with SLE and 578 healthy controls met the inclusion criteria.

“Pooled analysis revealed significantly decreased immunogenicity of H1N1 influenza vaccine in SLE patients compared to healthy controls for both seroprotection rates (OR 0.34 [95% CI 0.21– 0.55]) and seroconversion rates (OR 0.34 [95% CI 0.21–0.56]) with significant statistical heterogeneity for seroconversion (T²=0.37; P=0.01; I²=0.54),” they found.

The meta-analysis also revealed significantly decreased seroprotection rates with H3N2 (OR 0.34 [95% CI 0.18–0.66]) and B (OR 0.40 [95% CI 0.22–0.73]) influenza vaccines; however, a decrease in seroconversion rates for H3N2 (OR 0.55 [95% CI 0.21–1.45]) and B (OR 0.44 [95% CI 0.19–1.01]) influenza was not significant.

Compared with healthy controls (n=226), subgroup analyses that identified patients with SLE not taking corticosteroids or immunosuppressants (n=209) showed decreased seroprotection (OR 0.60 [95% CI 0.35–1.01]) and seroconversion rates (OR 0.64 [95% CI 0.42–0.98]).

“Specific vaccination schemes, such as the use of a second injection or the use of adjuvant vaccines, should be evaluated in SLE patients,” the researchers added.