Background The 23-valent capsular polysaccharide pneumococcal vaccine, Pneumovax, protects against invasive pneumococcal pneumonia and is indicated for patients with chronic autoimmune diseases and/or on chronic immunosuppressive treatment. The effect of polysaccharide vaccines on the immune system and the inflammatory response are not well defined. Recent data suggest that polysaccharide vaccines regulate the immune and inflammatory responses in animal models of Systemic Lupus Erythematosus (SLE) [1,2].

Objectives To study the epidemiology and in-hospital outcomes of pneumococcal vaccination in SLE patients.

Methods All hospitalized patients aged greater than 18 years included in the nationwide inpatient sample (NIS) 2011 database with a confirmed discharge diagnosis of SLE, as per the ICD-9-CM code 710.0 were identified. Lupus nephritis patients were identified by the ICD-9-CM code 583.81, whereas pneumococcal vaccination was identified by the ICD-9-CM code V03.82. NIS is the largest all-payer inpatient care database in the United States with approximately 8 million hospitalizations each year. Discharge weights were used to enable nationwide estimates.

Results A total of 193,293 adult patients with SLE were identified. 172,448 (89.22%) were females and 1,755 (0.91%) patients received pneumococcal vaccination during the hospitalization. In this inpatient SLE cohort 92,974 (48.1%) were Caucasian, 56,782 (29.38%) were African American and 21,249 (10.99%) were Hispanic. Hispanic patients had a significantly higher rate of vaccination 1.43% as compared to 0.8% of Caucasian and 0.9% of African American patients (p<0.0001).

Lupus nephritis was a diagnosis code in 16,824 patients (0.9%). Among the patients with lupus nephritis, 203 (1.2%) vaccinated with pneumovax during the hospitalization. Mortality rates among the non-vaccinated lupus nephritis patients was 1.2% (208 out of 16,824); however no deaths were reported in the vaccinated patients.

A total of 3,390 (1.75%) SLE patients died during hospitalization, 3,380 patients had not received pneumococcal vaccination. Mortality percentage of SLE patients who did not receive vaccination was 1.76% (3,380/191,538) whereas mortality percentage in patients who received vaccination was 0.56% (10/1,755), (p<0.001).

Conclusions In this nationwide study, pneumococcal vaccination was associated with decreased in-hospital mortality in SLE and lupus nephritis patients. Further prospective studies need to be done to study the association.

References

1. How Bacterial Carbohydrates Influence the Adaptive Immune System. Fikri Y. Avci; Dennis L. Kasper, Annu. Rev. Immunol. 2010.28:107-130.

2. Pneumococcal Polysaccharide Vaccination Regulates T and B Lymphocyte Cytokine Responses and Decreases Kidney Stat1 Levels In MRL/Lpr Mice In Vivo. Gazivoda, Victor; Mehta, Shikha; Wang, Luhan; Ash, Julia; Sperber, Kirk E; Tassiulas, Ioannis, American College of Rheumatology Annual Meeting 2013, Abstract #568.

Disclosure of Interest : None declared

DOI 10.1136/annrheumdis-2014-eular.4787