Editor's comment: Cortisol is a steroid hormone produced by the adrenal gland. Some of its functions include helping the body manage stress and aiding in the metabolism of sugar and fat. Cortisol levels cycle throughout the day. Normally they are highest around 7 a.m. and drop very low in the evening. For people who sleep during the day and are up at night, this pattern may be reversed.
Circadian rhythm of serum cortisol in female patients with fibromyalgia syndrome.
By G. Fatima, et al.
Fibromyalgia syndrome (FMS) patients have disturbed sleep patterns which may lead to altered circadian rhythm in serum cortisol secretion. The aim of this study was to assess circadian changes, if any, in serum cortisol levels in female patients with FMS.
Cortisol levels were estimated every 6 h during 24 h period; in 40 female patients satisfying ACR criteria for FMS (Age 36.4 ± 9.9), and 40 healthy females without FMS (Age 33.8 ± 11.1).
A significant difference in the night time serum cortisol level was observed among the patients and control groups (patients, 12.9 ± 9.7 controls 5.8 ± 3.0; p < 0.01).
However, no significant difference was found in serum cortisol levels in patients and control groups in the morning (patients, 28.4 ± 13.2 controls, 27.6 ± 14.5; p > 0.05), afternoon (patients, 14.4 ± 5.6 controls, 14.0 ± 6.6; p > 0.05) and evening hours (patients, 10.9 ± 5.8 controls, 8.9 ± 3.6; p > 0.05).
It could be concluded that there is an abnormality in circadian secretion of cortisol in female FMS patients.
Source: Indian Journal of Clinical Biochemistry, April 2013. By Fatima G, Das SK, Mahdi AA, Verma NS, Khan FH, Tiwari AM, Jafer T, Anjum B. King George's Medical University, Lucknow, 226003 UP India.