Circadian rhythms in arthritis: hormonal effects on the immune/inflammatory reaction

Autoimmun Rev. 2008 Jan;7(3):223-8. doi: 10.1016/j.autrev.2007.11.019. Epub 2007 Dec 3.


Biological signaling and rhythms occur in a complex network with participation and interaction of the central nervous system, the autonomic nervous system, the endocrine glands, peripheral endocrine tissues and the immune system. It is a clinical observation that patients affected by chronic immune/inflammatory conditions (i.e. rheumatoid arthritis/RA) exhibit circadian, circamensual (females) and circannual rhythms of disease-related symptoms. Proinflammatory cytokines exhibit a peculiar rhythmicity, in particular serum TNF and serum IL-6, and together with other relevant immunological parameters display an elevation in the early morning hours in patients with RA. As a matter of fact, RA patients particularly experience joint pain, morning stiffness, and functional disability in the early morning hours. Since circadian rhythmicity of neuroendocrine pathways is closely coupled to immune/inflammatory reactions, new aspects at least concerning RA management are suggested. In particular, further investigations will indicate whether timed release of immunosuppressive/antiinflammatory drugs will have increased efficacy and whether dosages can be reduced below critical levels above which adverse events appear.

Publication types

  • Review

MeSH terms

  • Arthritis / immunology
  • Arthritis / physiopathology*
  • Circadian Rhythm / immunology*
  • Hormones / blood*
  • Humans
  • Inflammation / physiopathology


  • Hormones