Characterisation of breathing and associated central autonomic dysfunction in the Rett disorder

• Published in: Archives of disease in childhood 2001-07, Vol.85 (1), p.29-37
• Main Authors: Julu, P O O, Kerr, A M, Apartopoulos, F, Al-Rawas, S, Engerström, I Witt, Engerström, L, Jamal, G A, Hansen, S
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Age Factors; Age groups; Analysis of Variance; Autonomic nervous system; Autonomic Nervous System Diseases - blood; Autonomic Nervous System Diseases - etiology; Autonomic Nervous System Diseases - physiopathology; autonomic system; Baroreflex - physiology; Biological and medical sciences; Blood Gas Monitoring, Transcutaneous; Blood pressure; Blood Pressure - physiology; brain stem; Case Records; Case-Control Studies; Cheyne-Stokes Respiration - blood; Cheyne-Stokes Respiration - etiology; Cheyne-Stokes Respiration - physiopathology; Child; Child, Preschool; Children; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Diseases; dysautonomia; Electrocardiography; Electroencephalography; Epilepsy; Female; General and Acute Paediatrics; Heart - physiopathology; Heart rate; Heart Rate - physiology; Humans; Measurement; Medical sciences; Mutation; Nervous system, Autonomic; Neurology; Pediatric diseases; Physical Disabilities; Physiological aspects; Plethysmography; Reflexes; Regression (Statistics); Respiration; Respiration Disorders - blood; Respiration Disorders - etiology; Respiration Disorders - physiopathology; Respiratory Mechanics - physiology; Rett disorder; Rett syndrome; Rett Syndrome - blood; Rett Syndrome - complications; Rett Syndrome - physiopathology; Rhythm; Signal transduction; Statistical Analysis; Statistical Significance; Studies; Testing; Valsalva Maneuver; Variance analysis
• ISSN: 0003-9888; 1468-2044
• DOI: 10.1136/adc.85.1.29

AIM To investigate breathing rhythm and brain stem autonomic control in patients with Rett disorder. SETTING Two university teaching hospitals in the United Kingdom and the Rett Centre, Sweden. PATIENTS 56 female patients with Rett disorder, aged 2–35 years; 11 controls aged 5–28 years. DESIGN One hour recordings of breathing movement, blood pressure, ECG R-R interval, heart rate, transcutaneous blood gases, cardiac vagal tone, and cardiac sensitivity to baroreflex measured on-line with synchronous EEG and video. Breathing rhythms were analysed in 47 cases. RESULTS Respiratory rhythm was normal during sleep and abnormal in the waking state. Forced and apneustic breathing were prominent among 5–10 year olds, and Valsalva breathing in the over 18 year olds, who were also most likely to breathe normally. Inadequate breathing peaked among 10–18 year olds. Inadequate and exaggerated breathing was associated with vacant spells. Resting cardiac vagal tone and cardiac sensitivity to baroreflex were reduced. CONCLUSIONS Labile respiratory rhythms and poor integrative inhibition in Rett disorder suggest brain immaturity. Linking this to an early monoaminergic defect suggests possible targets for the MECP2 gene in clinical intervention. Exaggerated and inadequate autonomic responses may contribute to sudden death.