Prevalence of Fibromyalgia in Vasovagal Syncope

Maite Vallejo, PhD; Laura-Aline Martínez-Martínez, MD; Saulo Grijalva-Quijada; Hector-Manuel Olguín-Ruvalcaba; Elizabeth Salas, RN; Antonio G. Hermosillo, MD; Manuel Cárdenas, MD; Manuel Martínez-Lavín, MD


J Clin Rheumatol. 2013;19(3):111-114. 

In This Article

Abstract and Introduction


Background: Vasovagal syncope is an acute manifestation of autonomic nervous system dysfunction. This type of syncope is often associated with other dysautonomic expressions such as migraine, gastroparesis, or postural tachycardia syndrome. Autonomic nervous system dysfunction has been proposed as a key element in the pathogenesis of fibromyalgia.

Objectives: The objectives of this study were to estimate the frequency of fibromyalgia in a sample of patients with vasovagal syncope and also to correlate the presence of syncope and fibromyalgia with different dysautonomic manifestations.

Methods: We studied 50 consecutive patients with vasovagal syncope seen at the Syncope Unit of the National Cardiology Institute of Mexico between June 2009 and June 2012. All individuals filled out the Composite Autonomic Symptoms and Signs questionnaire and the Fibromyalgia Impact Questionnaire. All cases underwent a head-up tilt test. A rheumatologist examined all participants to assess the presence of fibromyalgia.

Results: The median age of the studied population was 21 years. Sixty-eight percent of participants were women. Eight cases (16%) had concomitant fibromyalgia. Significantly, all fibromyalgia cases were female. This subgroup of fibromyalgia subjects had more secretomotor complaints (mainly dry eyes and dry mouth) and more bowel constipation than the remainder of the group. Also in this subgroup of fibromyalgia subjects, several significant associations were found between age, blood pressure, number of syncopal episodes, constipation, insomnia, pupillomotor impairment, and disability. In contrast, no correlations were found in the subgroup of fainters without fibromyalgia.

Conclusions: Fibromyalgia was relatively frequent in these women with vasovagal syncope and could be associated with dysautonomic symptoms. Therefore, it seems important to search for dysautonomic comorbidities in patients with vasovagal syncope and/or fibromyalgia, to provide a patient-centered holistic approach, instead of the often currently used therapeutic partition.


Vasovagal syncope is a common health problem with medical, social, and economical implication. The frequency of this type of syncope varies with age, gender, and cause. Young fainters are mostly women, whereas elderly affected individuals are more frequently men.[1,2] The peak incidence of syncope occurs around the age of 15 years. Estimates of lifetime cumulative syncope incidence in the general population are in the order of 35%.[3,4]

Vasovagal syncope is the result of the sudden sympathetic nervous system withdrawal with or without vagally mediated bradycardia that may evolve into asystole, These autonomic changes produce an abrupt but transient loss of consciousness associated to loss of postural tone followed by rapid, usually complete recovery without the need for intervention.[5]

Vasovagal syncope is often associated to other dysautonomic complaints such as migraine, gastroparesis, and postural tachycardia syndrome.[6] On the other hand, a consistent line of investigation proposes that dysautonomia plays a major role in the pathogenesis of fibromyalgia (FM). Heart rate variability analyses have shown that FM patients have a consistent pattern of sympathetic hyperactivity associated to sympathetic hyporeactivity to different stressors. This autonomic dysfunction provides a coherent explanation for FM multisystem symptoms including its main complaint, widespread pain. It has been proposed that FM pain could be sympathetically maintained (reviewed in Martínez-Lavín[7]). Furthermore, genetic studies support FM's dysautonomic nature. Patients with FM have gene polymorphisms associated to defective catecholamine-clearing enzymes[8] or to defective adrenergic receptors.[9]

The purpose of our study was to estimate the frequency of FM in a sample of patients with vasovagal syncope and also to correlate the presence of syncope and FM with different dysautonomic complaints.