title: Cardiac Sympathetic Hyperactivity in Patients with Chronic Obstructive Pulmonary Disease and Obstructive Sleep Apnea.
abstract: Obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) coexist in 0.5-1% of the general population. Both OSA and COPD are associated with increased sympathetic nervous activity, and patients affected by both disorders have higher risk for increased morbidity and mortality as compared with patients with COPD or OSA alone. We tested the hypothesis that patients with COPD and OSA (Overlap syndrome) have higher sympathetic and lower parasympathetic modulation of heart rate variability (HRV) in comparison with patients suffering from COPD or OSA alone. HRV indices in the frequency domain were evaluated from daytime electrocardiographic recordings in 14 patients with both severe OSA (apnea-hypopnea index ≥ 30) and mild-to-moderate COPD and compared with those with OSA (n = 24) or COPD (n = 16) alone. We found that, in the Overlap syndrome group, high-frequency (HF, 0.4-0.15 Hz) power was significantly lower (0.18 nu vs 0.34 nu in OSA and 0.44 nu in COPD patients, p < 0.01) and low-frequency (LF, 0.15-0.05 Hz) power was significantly greater (0.82 nu vs 0.66 nu in OSA and 0.57 nu in COPD patients, p < 0.01) compared with COPD and OSA groups. Patients with both OSA and COPD had higher LF/HF ratio as compared with patients in OSA and COPD groups (4.5 [5.9] vs 1.9 [2.6] and 1.3 [1.3], respectively, p < 0.01). For the Overlap syndrome group, there was a significant direct relationship between LF/HF ratio and residual volume (r2= 0.62, p = 0.007). These findings show that patients with both OSA and COPD have higher sympathetic modulation of heart rate compared with those with OSA or COPD alone. Furthermore, the findings provide a potential mechanism for the increased morbidity and mortality reported in patients suffering from both disorders, suggesting new therapeutic perspectives in Overlap syndrome.
authors.affiliation: a Respiratory Pathophysiology and Sleep Laboratory, Department of Medicine , M. Mellini Hospital , Chiari , Italy.|b Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology , Brigham & Women's Hospital & Harvard Medical School , Boston , Massachusetts.
authors.forename: Luigi
authors.initials: L
authors.lastname: Taranto-Montemurro
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Ludovico
authors.initials: L
authors.lastname: Messineo
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Perger
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Maroon
authors.initials: M
authors.lastname: Salameh
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Pini
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Luciano
authors.initials: L
authors.lastname: Corda
authors.affiliation: a Respiratory Pathophysiology and Sleep Laboratory, Department of Medicine , M. Mellini Hospital , Chiari , Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Ferliga
authors.affiliation: c Respiratory Medicine and Sleep Laboratory, Department of Internal Medicine , Spedali Civili di Brescia, University of Brescia , Brescia , Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Tantucci
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004562:Electrocardiography; D005541:Forced Expiratory Volume; D006321:Heart / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000503:physiopathology*; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology*; D013564:Sympathetic Nervous System / Q000503:physiopathology; D014109:Total Lung Capacity; D014797:Vital Capacity
keywords: Overlap Syndrome; autonomic activation; cardiovascular risk; sleep disordered breathing