Original Article

Circadian clock mechanisms in adrenal adenomas are not related to osteopenia and osteoporosis

Konstantinos Katsoulis¹, Dimitrios Ioannidis¹, Georgios Karageorgos¹, George I. Lambrou²

1. Department of Endocrinology, Diabetes and Metabolism,“Amalia Fleming” General Hospital, Athens, Greece
2. First Department of Pediatrics, University of Athens, Choremeio Research Laboratory,National and Kapodistrian University of Athens, Greece

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Keywords: Οsteopenia, Οsteoporosis, Αdenoma, Cortisol, Circadian rhythm

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Abstract

Background: It is known that humans live under the strong influence of light/dark cycles associated with the day/night changes created by the 24-hour rotation of the earth. Yet, it is possible that the circadian rhythm could be disrupted from the presence of a disease and/or changes in body homeostasis. The aim of the present study was to search for an association in patients with adrenal adenomas between cortisol circadian rhythm and osteopathies. Materials and Methods: Twenty eight patients with a history of adenoma, osteopathy or both participated. Patients were tested for routine biochemical factors as well as cortisol levels at 8 a.m., 1 p.m., 5 p.m. and 11 p.m., as well as ACTH and urine cortisol. Results: Significant differences were observed in SGOT levels Free-T₄, FSH and K⁺ in subjects with and without any history of osteopenia or osteoporosis manifesting lower levels as compared to subjects with a history of osteopenia or osteoporosis. At the same time cortisol remained similar among all patient groups. Discussion: Although there is no conclusive evidence, cortisol levels appear to remain untouched by the disease states and thus it appears that circadian rhythms are regulated through an alternative circuitry.

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