title: Cardiac autonomic functions in children with familial Mediterranean fever.
abstract: Familial Mediterranean fever (FMF) is the most common inherited autoinflammatory disease in the world. The long-term effects of subclinical inflammation in FMF are not well recognized. Some studies have suggested that FMF is associated with cardiac autonomic dysfunction in adult FMF patients. The objective of this study was to investigate the cardiac autonomic functions in pediatric FMF patients by using several autonomic tests. Thirty-five patients with FMF and 35 healthy controls were enrolled in this cross-sectional study. Demographic data, disease-specific data, and orthostatic symptoms were recorded. In all participants, 12-lead electrocardiography (ECG), 24 h ambulatory electrocardiographic monitoring, transthoracic echocardiography, treadmill exercise test, and head upright tilt-table (HUTT) test were performed. The heart rate recovery (HRR) indices of the two groups were similar. Also, chronotropic response was similar in both groups. The time-domain parameters of heart rate variability (HRV) were similar in both groups, except mean RR (p = 0.024). Frequencies of ventricular and supraventricular ectopic stimuli were similar in both groups. There were no statistically significant differences between the groups in average QT and average corrected QT interval length, average QT interval dispersion, and average QT corrected dispersion. There was no significant difference between the two groups regarding the ratio of clinical dysautonomic reactions on HUTT. However, we observed a significantly higher rate of dysautonomic reactions on HUTT in patients with exertional leg pain than that in patients without (p = 0.013). When the fractal dimension of time curves were compared, FMF patients exhibited significantly lower diastolic blood pressure parameters than controls in response to HUTT. Cardiovascular autonomic dysfunction in children with FMF is not prominent. Particularly, patients with exertional leg pain are more prone to have dysautonomic features. Further studies are needed to elucidate the exact mechanisms leading to impaired cardiac autonomic functions in FMF.
authors.affiliation: Department of Pediatrics, Division of Cardiology, Dokuz Eylül University Faculty of Medicine, Izmir, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Şahin
authors.affiliation: Department of Pediatrics, Division of Cardiology, Dokuz Eylül University Faculty of Medicine, Izmir, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kır
authors.affiliation: Department of Pediatrics, Division of Rheumatology, Dokuz Eylül University Hospital, 35340, Balçova, Izmir, Turkey. balahan.bora@deu.edu.tr.
authors.forename: Balahan
authors.initials: B
authors.lastname: Makay
authors.affiliation: Department of Public Health, Dokuz Eylül University Health Sciences Institute, Izmir, Turkey.
authors.forename: Pembe
authors.initials: P
authors.lastname: Keskinoğlu
authors.affiliation: Department of Medical Genetics, Dokuz Eylül University Hospital, Izmir, Turkey.
authors.forename: Elçin
authors.initials: E
authors.lastname: Bora
authors.affiliation: Department of Pediatrics, Division of Rheumatology, Dokuz Eylül University Hospital, 35340, Balçova, Izmir, Turkey.
authors.forename: Erbil
authors.initials: E
authors.lastname: Ünsal
authors.affiliation: Department of Pediatrics, Division of Cardiology, Dokuz Eylül University Faculty of Medicine, Izmir, Turkey.
authors.forename: Nurettin
authors.initials: N
authors.lastname: Ünal
mesh_terms: D000293:Adolescent; D001341:Autonomic Nervous System / Q000503:physiopathology*; D001794:Blood Pressure / Q000502:physiology*; D002648:Child; D003430:Cross-Sectional Studies; D004562:Electrocardiography; D015716:Electrocardiography, Ambulatory; D010505:Familial Mediterranean Fever / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D054969:Primary Dysautonomias / Q000150:complications / Q000503:physiopathology*
keywords: Autonomic Function; Familial Mediterranean fever; Head upright tilt test