TNFSF11 and chronic obstructive pulmonary disease: High cytokines levels may contribute to increase the risk of osteoporosis and bone fractures in chronic inflammatory disease including COPD [8] and inflammatory bowel disease [9], and the relevance of RANKL pathway in bone health is indicated by the efficacy of drugs impinging upon RANKL in the treatment of osteoporosis in elderly women [10], including patients in CKD stage 2–4 [11].