Consequences of comorbid sleep apnea in the metabolic syndrome - Implications for cardiovascular risk

Ivani C. Trombetta, Virend K. Somers, Cristiane Maki-Nunes, Luciano F. Drager, Edgar Toschi-Dias, Maria Janieire N.N. Alves, Raffael F. Fraga, Maria Urbana P.B. Rondon, Maíta G. Bechara, Geraldo Lorenzi-Filho, Carlos E. Negrão

Research output: Contribution to journalArticlepeer-review

54 Scopus citations


Study Objectives: Metabolic syndrome (MetSyn) increases overall cardiovascular risk. MetSyn is also strongly associated with obstructive sleep apnea (OSA), and these 2 conditions share similar comorbidities. Whether OSA increases cardiovascular risk in patients with the MetSyn has not been investigated. We examined how the presence of OSA in patients with MetSyn affected hemodynamic and autonomic variables associated with poor cardiovascular outcome. Design: Prospective clinical study. Participants: We studied 36 patients with MetSyn (ATP-III) divided into 2 groups matched for age and sex: (1) MetSyn+OSA (n = 18) and (2) MetSyn-OSA (n = 18). Measurements: OSA was defined by an apnea-hypopnea index (AHI) > 15 events/hour by polysomnography. We recorded muscle sympathetic nerve activity (MSNA - microneurography), heart rate (HR), and blood pressure (BP - Finapres). Baroreflex sensitivity (BRS) was analyzed by spontaneous BP and HR fluctuations. Results: MSNA (34 ± 2 vs 28 ± 1 bursts/min, P = 0.02) and mean BP (111 ± 3 vs. 99 ± 2 mm Hg, P = 0.003) were higher in patients with MetSyn+OSA versus patients with MetSyn-OSA. Patients with MetSyn+OSA had lower spontaneous BRS for increases (7.6 ± 0.6 vs 12.2 ± 1.2 msec/mm Hg, P = 0.003) and decreases (7.2 ± 0.6 vs 11.9 ± 1.6 msec/mm Hg, P = 0.01) in BP. MSNA was correlated with AHI (r = 0.48; P = 0.009) and minimum nocturnal oxygen saturation (r = -0.38, P = 0.04). Conclusion: Patients with MetSyn and comorbid OSA have higher BP, higher sympathetic drive, and diminished BRS, compared with patients with MetSyn without OSA. These adverse cardiovascular and autonomic consequences of OSA may be associated with poorer outcomes in these patients. Moreover, increased BP and sympathetic drive in patients with MetSyn+OSA may be linked, in part, to impairment of baroreflex gain.

Original languageEnglish (US)
Pages (from-to)1193-1199
Number of pages7
Issue number9
StatePublished - Sep 1 2010


  • Baroreflex control
  • Cardiovascular risk
  • Metabolic syndrome
  • Sleep apnea
  • Sympathetic activation

ASJC Scopus subject areas

  • Clinical Neurology
  • Physiology (medical)


Dive into the research topics of 'Consequences of comorbid sleep apnea in the metabolic syndrome - Implications for cardiovascular risk'. Together they form a unique fingerprint.

Cite this