TNF and benign prostatic hyperplasia: The metabolic syndrome is associated with the occurrence of chronic inflammation that remains at a low level, which is characterised by the predominance of pro-inflammatory factors in the systemic circulation, e.g., IL-6 and TNFα [35–37] and IL-18 [22, 38], which are involved in the pathogenesis of LUTS/BPH [39, 40].