Publisher: Informa Healthcare
ISSN: 0742-0528
Source: Chronobiology International, Vol.22, Iss.6, 2005-11, pp. : 1157-1335
Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.
Abstract
A. Reinberg Unité de Chronobiologie. Fondation A de Rothschild‐ Paris 75940 Cedex 19‐France Objective: New findings related to internal desynchronization (ID) in man and its inter‐individual variability lead to the reconsideration of some basic definitions. In the same subject, during longitudinal studies ( n ≥8 days), the circadian period of a set of variables can differ from one another and from 24 h, even in the presence of natural zeitgebers. This was documented for e.g. , activity/rest, oral temperature, heart rate, grip strength of both hands, and cognitive performances (Reinberg et al., 1984, 1994, 1997, 2003; Motohashi, 1990; Ashkenazi et al., 1997; Shub et al., 1997; Chandrawanshi and Pati, 2000). Several methods, including power spectra analyses, helped to demonstrate that ID can be observed in many circumstances: shift work, placebo effect on healthy subjects, work in the high Arctic Summer, sport training, etc. Results: Four types of symptoms characterize the intolerance to shift work: persistent fatigue, sleep alterations, behavioral changes, permanent use of sleeping pills (which are of no help) (Andlauer, et al., 1979; Reinberg, et al., 1988; 1992). Good tolerance (symptom free subjects) to shift schedules was found in 56% of workers and the poor tolerance in 44%, based on a series of prospective studies involving more than 140 shift workers. ID was found in all non‐tolerant shift workers, but also in tolerant ones. In a group of 40 healthy day workers, ID was found in 35%, with gender‐related differences. In addition, emphasis is given to the fact that many diseases, e.g. , nocturnal asthma, chronic pain, persisting anxiety and stress, fibroma, and prostate adenoma, involve chronic deprivation of sleep at night and constitute conditions that mimic the presentation of non‐tolerant shift workers with ID. Conclusions: ID appears to be a rather common phenomenon. In some individuals, ID causes no clinical symptoms and the new concept of “allochronism” [allo=different] is proposed to designate a variant of human temporal organization with no pathologic implication. The term “dyschronism” [dys=abnormal] is then restricted to ID associated with a set of symptoms similar to those of non‐tolerant shift workers. The term “euchronism” [eu=normal] may be used when circadian parameters (τ, Ø, A, and M) of documented variables are within the confidence limits of pertinent reference values.
Related content
Twin Research, Vol. 1, Iss. 2, 1998-06 ,pp. :
By Hunt Curtiss
Cell Biology and Toxicology, Vol. 25, Iss. 2, 2009-04 ,pp. :
Twin Research, Vol. 1, Iss. 3, 1998-09 ,pp. :
European Journal of Morphology, Vol. 35, Iss. 5, 1997-12 ,pp. :
Current Genomics, Vol. 16, Iss. 1, 2015-02 ,pp. :