LAUSR

Objectives: The most important determinant of the circadian influences of sleep and wakefulness on BP is the nighttime parasympathetic prevalence and daytime sympathetic prevalence including many other physiologic mechanisms known either to induce sleep or determine arousal, may play an important role in the mediation of sleep influences on blood pressure (BP), and this disturbed sleep and high blood pressure is very common in Fibromyalgia Syndrome patients. Each stage of sleep exerts an effect on BP regulating and contributing to its circadian (24-h) rhythm. Alteration of one or more of such mechanisms may be reflected in altered circadian BP rhythms in Fibromyalgia Syndrome. Methods: Sleep and arousal-related mechanisms that is disturbed in FMS patients along with the parameters that effect circadian BP rhythms including neurohumoral sleep factors like melatonin and waking factor like Cortisol was done in 50 FMS patients and equal number of controls. Ambulatory BP monitoring (ABPM) was performed in 50 FMS and compared to those of 50 control subjects matched for age, gender and daytime BP. Results: The non-dipping pattern (a less than 10% reduction in nocturnal BP) was more prevalent in FMS than in control subjects (89 versus 64%, P < 0.01). Nighttime BP was higher in FMS than in control subjects (P < 0.01 and < 0.001 for systolic BP (SBP) and diastolic BP (DBP), respectively). Whereas, the night time levels of melatonin was found to be significantly lower, and that of Cortisol levels were found to be higher during night hours among FMS patients group. Conclusion: An abnormal circadian BP profile is highly prevalent among FMS patients. These changes in the circadian BP rhythm are known to be strongly related to one's risk of cardiovascular morbidity and mortality and extreme severity of FMS symptom.