Cardiovascular reactivity in fibromyalgia: evidence for pathogenic heterogeneity

To evaluate disease-specific cardiovascular reactivity patterns in patients with fibromyalgia (FM) using a recently described method called fractal and recurrence analysis score (FRAS).

The study group included 30 women with FM, average age 46.7 years (SD 7.03). An age matched group of 30 women with other rheumatic disorders or having a dysautonomic background [chronic fatigue syndrome (CFS), non-CFS fatigue, neurally mediated syncope, and psoriatic arthritis (PsA)] served as controls. Subjects were evaluated with a head-up tilt test with beat-to-beat recording of the heart rate (HR) and pulse transit time. A 10-minute supine phase was followed by 600 cardiac cycles recorded on tilt. Data were processed by recurrence plot and fractal analysis. Variables acting as independent predictors of the cardiovascular reactivity were identified in FM patients versus controls.

No statistically significant differences were found between the groups by univariate analysis comparing 92 variables of cardiovascular reactivity in FM patients compared to controls.

Study of cardiovascular reactivity utilizing a head-up tilt test and processing the data using the FRAS method did not reveal a specific FM-associated abnormality. Our data confirm studies that utilized other methodologies and reached similar conclusions. Patients with FM represent a heterogenous group with respect to their pattern of cardiovascular reactivity.