CRP and inflammatory bowel disease: Experimental studies of sleep deprivation demonstrate that sleep disturbance results in increases in inflammatory markers associated with IBD, such as interleukin-6 (IL-6), TNF-α, and C-reactive protein (CRP).29,30 Conversely, research also indicates that sleep parameters respond to immune system challenges (eg, endotoxin injection and IL-6 injection).29 These bidirectional relationships likely lead to a cycle wherein sleep disturbance and IBD worsen and maintain one another, deteriorating quality of life and worsening overall disease activity and inflammation.31