Effect of CPAP therapy on cardiovascular risk in severe obstructive sleep apnea:the MMP:TIMP balance

Introduction: In obstructive sleep apnea (OSAS), intermittent hypoxemia results in persistent inflammation and increased oxidative stress that induces atherogenic processes in the vascular system. Matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) play important regulatory roles in the development of atherosclerosis. An MMP:TIMP imbalance leads to inflammatory cell infiltration, collagen deposition and plaque formation. Aims: Our goal was to analyze the short- and long-term effects of Continuous Positive Airway Pressure (CPAP) on the serum levels of MMP and TIMP proteins (MMP1, -2, -3, -4, -8, -9, -10, -13, TIMP1, -2, -4) and correlate them with various physiological parameters. Methods: 7 MMPs and 3 TIMPs were measured longitudinally in the serum of 31 patients diagnosed with severe OSAS (apopnoe-hypopnoe index [AHI]:> 30/h) on quantitative antibody microarrays. Data obtained at the time of diagnosis, at 2 and 6 months and 5 years after the start of CPAP treatment were compared statistically. Results: CPAP treatment resulted in the normalization of patients’ AHI, ODI and Epworth scores already at 2 months (p Conclusions: In severe OSAS, changes of serum MMP and TIMP levels show no correlation with CPAP induced changes of sleep parameters. Long term changes in MMP:TIMP ratios may affect the development of atherosclerosis in severe OSAS.