Effects of nasal CPAP treatment on insulin resistance, lipid profile, and plasma leptin in sleep apnea

Lung. Mar-Apr 2009;187(2):75-81. doi: 10.1007/s00408-008-9131-5. Epub 2009 Jan 7.

Abstract

Background: Obstructive sleep apnea has been linked with metabolic syndrome characterized by dyslipidemia, dyscoagulation, hypertension, and diabetes mellitus type 2 and their cardiovascular consequences. This study was designed to determine the effects of 8 weeks of therapy with continuous positive airway pressure (CPAP) on insulin resistance, glucose, and lipid profile, and the relationship between leptin and insulin-resistance parameters in patients with moderate-to-severe obstructive sleep apnea.

Methods: In 44 patients, serum cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, very low-density lipoprotein, leptin, and insulin parameters were measured at baseline and after 8 weeks of CPAP. Insulin resistance index was based on the homeostasis model assessment (HOMA-IR) method. Insulin sensitivity (HOMA-S) and insulin secretion capacity (HOMA-beta) also were calculated. Thirteen patients were excluded from statistical analyses due to noncompliant CPAP usage (<4 h night(-1)).

Results: In 31 patients who used CPAP for > or =4 h night(-1), CPAP therapy reduced total cholesterol (P < 0.05), low-density lipoprotein (P < 0.05), and leptin (P < 0.05). Circulating leptin levels showed significant correlation with both HOMA-S and HOMA-IR at baseline and follow-up (P = 0.03 for all). In addition, there was no correlation between HOMA-IR and the severity of sleep apnea, which was shown by apnea-hypopnea index.

Conclusions: In patients with moderate-to-severe obstructive sleep apnea, compliant CPAP usage may improve insulin secretion capacity, reduce leptin, total cholesterol, and low-density lipoprotein levels. Leptin showed significant relationship with insulin resistance, and this relationship remained after 8 weeks of CPAP therapy.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Biomarkers / blood
  • Blood Glucose / metabolism
  • Continuous Positive Airway Pressure*
  • Female
  • Humans
  • Insulin / blood
  • Insulin Resistance*
  • Leptin / blood*
  • Lipids / blood*
  • Male
  • Metabolic Syndrome / blood
  • Metabolic Syndrome / etiology
  • Metabolic Syndrome / physiopathology
  • Metabolic Syndrome / prevention & control
  • Middle Aged
  • Patient Compliance
  • Severity of Illness Index
  • Sleep Apnea Syndromes / blood
  • Sleep Apnea Syndromes / complications
  • Sleep Apnea Syndromes / physiopathology
  • Sleep Apnea Syndromes / therapy*
  • Time Factors
  • Treatment Outcome

Substances

  • Biomarkers
  • Blood Glucose
  • Insulin
  • Leptin
  • Lipids