Article Text

Clocks in the clinic: circadian rhythms in health and disease
  1. Rachael M Kelly1,
  2. Ultan Healy2,3,
  3. Seamus Sreenan2,3,
  4. John H McDermott2,3,
  5. Andrew N Coogan1
  1. 1 Department of Psychology, Maynooth University, National University of Ireland, Maynooth, Ireland
  2. 2 Academic Department of Endocrinology, Royal College of Surgeons in Ireland, Connolly Hospital Blanchardstown, Dublin, Ireland
  3. 3 3U Diabetes Consortium, Dublin, Ireland
  1. Correspondence to Rachael M Kelly, Department of Psychology, Maynooth University, Maynooth W23 A023, Ireland; rachael.kelly{at}


Circadian rhythms are endogenously generated recurring patterns of around 24 hours with well-established roles in physiology and behaviour. These circadian clocks are important in both the aetiology and treatment of various psychiatric and metabolic diseases. To maintain physiological homeostasis and optimal functioning, living life synchronised to these clocks is desirable; modern society, however, promotes a ‘24/7’ lifestyle where activity often occurs during the body’s ‘biological night’, resulting in mistimed sleep and circadian misalignment. This circadian desynchrony can increase the risk of disease and can also influence treatment response. Clinicians should be aware of the influence that circadian desynchrony can have on health and disease, in order to potentially develop new therapeutic strategies and to incorporate chronotherapeutics into current treatment strategies to enhance their utility.

  • Circadian rhythms
  • circadian misalignment
  • health
  • chronotherapeutics

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  • Contributors RMK performed the literature search and selection with guidance and supervision from ANC. RMK and ANC wrote the paper and RK prepared the figures. UH, JHMcD and SS contributed to the content and revised the paper. All authors were involved in the manuscript drafting. All authors agree and approve of the final version of the manuscript.

  • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Author note All contributors met the criteria for authorship.

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