C-reactive protein evolution in obstructive sleep apnoea patients under CPAP therapy.

Background: C-reactive protein (CRP) is recognized as a potential factor implicated in atherogenesis and associated cardiovascular morbidity. The aim of our study was to assess the CRP evolution during 1-year follow-up period in obstructive sleep apnoea (OSA) patients under CPAP treatment.

Methods: Five hundred and twenty-eight patients with newly diagnosed moderate to severe OSA were included. CRP was assessed before CPAP initiation and at the 3rd, 6th and 12th month of the follow-up period. Patients were divided into good and poor CPAP compliance groups.

Results: A significant reduction in CRP levels was observed after CPAP therapy (0·74±0·62mgdL(-1) vs. 0·31±0·29mgdL(-1) , P<0·001) in the whole patient group. The evolution of CRP values showed a gradual decrease at 3months with a steep decline at 6months, reaching a plateau after this time point. When the patients were divided into those with good and poor compliance with CPAP therapy, the above CRP evolution pattern was observed only in the former group.

Conclusion: Good CPAP compliance results in a significant CRP reduction. To achieve the best positive impact on cardiovascular morbidity and mortality, a time period of at least 6months of CPAP use is required.