Author + information
- Ivan Cundrle,
- Virend Somers,
- Prachi Singh,
- Bruce Johnson,
- Christopher Scott,
- Christelle van der Walt and
- Lyle Olson
Central sleep apnea (CSA) is frequent in heart failure patients and characterized by periodic hyperventilation and compensatory apnea. Leptin deficiency in animals promotes hyperventilation. Leptin expression by adipocytes is attenuated by natriuretic peptides. We hypothesized that in human heart failure leptin concentration is inversely related to natriuretic peptide concentration and that low leptin promotes CSA.
Consecutive ambulatory heart failure patients with NYHA class II–III were prospectively studied including measurement of serum leptin, BNP, carbon dioxide chemosensitivity by re–breathe, cardiopulmonary exercise testing and polysomnography (PSG). Subjects (n=29) were divided into subgroups by PSG: 1) CSA and 2) no CSA. Subjects with obstructive sleep apnea (n=15) were excluded from analysis. CSA was defined as a central apnea–hypopnea index (AHI) ≥ 15 by PSG; subgroups were compared by t–test. Logistic regression and ROC analysis were performed to evaluate parameters for detection of CSA. Data are summarized as mean ± SD and p < 0.05 considered significant.
Subjects with CSA had significantly higher BNP (919 ± 925 vs. 315 ± 445 pg/ml; p = 0.03), carbon dioxide chemosensitivity (2.39 ± 1.03 vs. 1.54 ± 0.35 l/min/mmHg; p = 0.01), impaired ventilatory efficiency (VE/VCO2) (43 ± 9 vs. 34 ± 7; p < 0.01) and lower leptin concentration (8 ± 10.7 vs. 17.1 ± 8.8 ng/ml; p < 0.01). Leptin concentration significantly inversely correlated with concentration of BNP (r = −0.63; p < 0.01), VE/VCO2 (r= −0.66; p < 0.01) and severity of CSA by AHI (r = −0.44; p = 0.02). Logistic regression analysis adjusted for age, gender, BMI and NYHA class demonstrated leptin to be independently associated with CSA with OR = 0.11 (95% CI 0.01 – 0.94; p = 0.04). ROC analysis demonstrated leptin to be the strongest independent predictor of CSA with AUC of 0.90 (p = 0.04).
In heart failure patients, low leptin promotes hyperventilation during sleep and exercise and is inversely related to BNP concentration. Inhibitory interactions between leptin and natriuretic peptides may be important in understanding ventilatory control in HF patients.
Special Session North, Room 120
Sunday, March 10, 2013, 10:45 a.m.–11:00 a.m.
Session Title: Young Investigator Awards Competition: Physiology, Pharmacology and Pathology
Abstract Category: Physiology, Pharmacology, Pathology
Presentation Number: 403–4
- 2013 American College of Cardiology Foundation