Interleukin 1 beta -511 C/T gene polymorphism and susceptibility to febrile seizures: a meta-analysis.

One previous meta-analysis found no evidence that interleukin 1 beta (IL-1β) -511 gene polymorphism was associated with febrile seizures (FS) by pooling a limited number of studies. However, it is necessary for the meta-analysis to reevaluate the relationship with more recent findings. Electronic databases were systematically searched for studies published before June 2011. Pooled odds ratios (OR) and 95% confidence interval (CI) were estimated by means of a genetic model free approach. Subgroup and sensitivity analyses were also performed. All statistical analyses were conducted using Stata 9.0. A total of eight studies, 728 FS cases and 1,223 controls, met the selection criteria. The results show a significant association between IL-1β -511 C/T gene polymorphism and FS (recessive genetic model TT vs. CC + CT: OR = 1.361, 95% CI: 1.065-1.738, P = 0.014). Subgroup analyses show a significant association in Asia (OR = 1.394, 95% CI: 1.005-1.935, P = 0.047), but not in Europe (OR = 1.387, 95% CI: 0.750-2.565, P = 0.298). IL-1β -511 C/T gene polymorphism may play a role in susceptibility to FS, especially in Asia. Geographic differences may be a critical factor in the risk of FS.