For example, a systematic review and meta-analysis of 29 prospective population-based studies found that a one standard deviation increase in the cytokines interleukin-6 (IL-6), IL-18 and tumour necrosis factor alpha (TNF-α) was associated with a 10-25% increase in the risk of non-fatal and fatal myocardial infarction 27. This evidence concerns the gene IL6 and myocardial infarction.