Invasive group A streptococcal disease: race, hypotension, and immunogenetics

To determine if there was an association between race and the incidence of hypotension among patients hospitalized for invasive group A streptococcal disease (IGASD).

Data were obtained from a retrospective cohort study of IGASD patients. The subjects were hospitalized throughout Florida for IGASD between 1996 and 2000 (N=151). The exposure variable for the current study was race (African Americans, Caucasians). The binary outcome was the presence of hypotension within 48 hours of hospital admission. A sensitivity analysis was performed to determine if a particular human leukocyte antigen (HLA) class II haplotype (DRB1*1501/DQB1*0602) confounded the association between race and the risk of hypotension. IGASD patients possessing this haplotype are less likely to experience hypotension with multiple organ failure.

We found that Caucasians had three times the odds of developing hypotension than African Americans (adjusted odds ratio=3.02, 95% confidence interval: 1.10-8.29, P=.03). The sensitivity analysis revealed that the HLA class II haplotype DRB1*1501/DQB1*0602 was most likely not a confounder.

Caucasians were significantly more likely than African Americans to develop the adverse outcome of hypotension within 48 hours of being hospitalized for IGASD. This excess risk is most likely not due to a particular host genetic factor, the HLA class II haplotype DRB1*1501/DQB1*0602.