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Circadian Rhythm- What Is a Circadian Rhythm?

From , former About.com Guide

Updated April 10, 2009

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Definition:

A circadian rhythm may be described as natural changes in a disease or physiological process that occur in any given 24 hour period. The term "circadian" originates from the Latin circa, meaning "around," and diem meaning "day." Combined the literal meaning is "approximately one day." A useful analogy is to think of it as a biological clock with certain physiological and biological processes taking place at specific times of the day. In relation to asthma, this internal body process regulates patterns of hormone production, inflammation, cell receptors, and other biological activities that can your affect asthma symptoms. A number of factors can affect your natural circadian rhythms and affect how well controlled your asthma is. For example:

  • Shift work
  • Pregnancy
  • Significant changes in sleep patterns and daily routine
  • Travel with time zone changes
  • Medications

Source:

Nocturnal asthma: circadian rhythms and therapeutic interventions. Am Rev Respir Dis. 1993 Jun;147(6 Pt 2):S25-8

Also Known As: biological clock

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