Interleukin-1β gene polymorphism associated with radiographic signs of osteoarthritis of the knee

Background. Osteoarthritis is recognized as a noninflammatory, progressive condition, the principal cause of which is regressive changes associated with aging and which pursues a chronic course. Recently, the involvement of genetic factors has been widely reported. The purpose of this study was to identify polymorphisms at particular risk of osteoarthritis of the knee for community-living middle-aged and elderly people. Methods. Focusing on 359 participants (ages 44-86 years) of the comprehensive health examination program (CHEP), we investigated the presence/absence of radiographic osteoarthritis (ROA) of the knee, and 11 types of gene polymorphisms and their association with ROA. Results. Interleukin-1 beta (IL1B) T-31C polymorphism was found to be associated with ROA. In the case of IL1B T-31C polymorphism in the ROA group, a significant difference was found between the groups combining the C/C genotype, the C/T genotype, and the T/T genotype. In particular, the genotypes with the C allele differed from the T/T genotype, with the morbidity rate being higher in the T/T group (odds ratio (OR) 2.04, 95% confidence interval (95%CI) 1.05-3.98, P = 0.036). Conclusion. Our results confirm that in IL1B T-31C with the T/T genotype, the rate of ROA was significantly higher than that with the C/C and C/T genotypes. It might be possible to implement active preventative measures, such as avoidance of obesity and excessive exercise loads, for carriers of IL1B T/T.