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Updated: Feb 23, 2026

Recording and Analysis of Circadian Rhythms in Running-wheel Activity in Rodents
Published on: January 24, 2013
Circaseptan Periodicity of Cardiovascular Diseases
Massimo Gallerani1, Marco Pala1, Ugo Fedeli2
1Department of Internal Medicine, Hospital of Ferrara, Azienda Ospedaliero-Universitaria, Via Aldo Moro 8, Ferrara 44124, Italy.
Abstract:
The occurrence of cardiovascular events shows a different distribution during the week, with many studies reporting a Monday peak, possibly related to the role of stress associated with commencing weekly activities. Furthermore, a higher mortality has been observed among patients hospitalized for cardiovascular and other disorders on weekends, a phenomenon known as "weekend effect." Such effect may be explained by a higher level of disease severity among patients admitted over the weekend, and/or by a poorer quality of care associated with shortage of staff, lower experience of personnel, and limited availability of therapeutic and diagnostic procedures.
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