Effects of continuous positive airway pressure on systemic inflammation in patients with moderate to severe obstructive sleep apnoea: a randomised controlled trial
- M Kohler1,
- L Ayers3,
- J C T Pepperell2,
- K L Packwood3,
- B Ferry3,
- N Crosthwaite1,
- S Craig1,
- M M Siccoli1,
- R J O Davies1,
- J R Stradling1
- 1Oxford Centre for Respiratory Medicine, Churchill Hospital, Oxford, UK
- 2Department of Respiratory Medicine, Musgrove Park Hospital, Taunton, UK
- 3Department of Clinical Immunology, Churchill Hospital, Oxford, UK
- Dr M Kohler, Oxford Centre for Respiratory Medicine, Churchill Hospital, Headington, Oxford OX3 7LJ, UK; Malcolm.K{at}bluewin.ch
- Received 20 February 2008
- Accepted 12 August 2008
- Published Online First 11 September 2008
Abstract
Background: Obstructive sleep apnoea syndrome (OSAS) has been associated with cardiovascular disease in epidemiological and observational studies. Continuous positive airway pressure (CPAP) is the treatment of choice for OSAS, but the impact of this intervention on systemic inflammation involved in the atherosclerotic process remains unclear.
Methods: 100 men with moderate–severe OSAS were randomised to therapeutic (n = 51) or subtherapeutic (n = 49) CPAP treatment for 4 weeks to investigate the effects of active treatment on inflammatory markers such as highly sensitive C reactive protein (hsCRP), interleukin (IL)6, interferon γ (IFNγ) and anti-inflammatory adiponectin.
Results: 4 weeks of therapeutic CPAP did not significantly change blood levels of hsCRP compared with the subtherapeutic control group (difference between median changes −0.24 mg/l (95% CI −0.88 to +0.24); p = 0.30). Plasma levels of IL6 and IFNγ did not change significantly following therapeutic compared with subtherapeutic CPAP (difference between median changes +0.52 and −0.07 pg/ml (95% CI −0.72 to +1.94 and −0.81 to +0.44); p = 0.45 and p = 0.82, respectively). Furthermore, 4 weeks of therapeutic CPAP did not significantly change levels of adiponectin in plasma compared with the subtherapeutic control group (difference between median changes +0.05 pg/ml (95% CI −0.36 to +0.47); p = 0.84). If patients with hsCRP values above 8 mg/l at baseline were excluded, differences between the changes in hsCRP, IL6, IFNγ and adiponectin after 4 weeks of CPAP were smaller, and again not statistically different between groups.
Conclusions: 4 weeks of CPAP treatment has no beneficial effect on blood markers of inflammation and adiponectin in patients with moderate–severe obstructive sleep apnoea.
Footnotes
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Funding: ResMed UK made an unrestricted donation to support research work in the Oxford Sleep Unit in 1998 and 2006.
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Competing interests: None.
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Ethics approval: The study was approved by the Oxford research ethics committee (COREC No 96.127).








