DNA methylation profiling in blood of OSA patients and controls

Obstructive sleep apnea (OSA) is associated with increased risk for cardiovascular morbidity and mortality. Epidemiological and animal models studies generate hypotheses for innovative strategies in OSA management by interfering intermediates mechanisms associated with cardiovascular complications. In this study, we interrogated DNA methylation profiles in 16 polysomnographically evaluated OSA patients (Apnea Hypopnea Index, AHI > 30) and 8 controls (AHI<5 events/h sleep). Blood samples were collected at initial visit (V1) and a year later (V2). OSA patients received Continuous Positive Air Pressure (CPAP) therapy with high adherence (> 4 hours/night). Control individuals did not receive CPAP therapy. Genomic DNA was treated with sodium bisulfite. Converted DNA was analyzed using Illumina’s Infinium Human Methylation 450 BeadChip assay. DNA methylation profiles enabled the prospective evaluation of inflammatory and epigenetics mechanism involved in cardiovascular complication of OSA patients compared with non OSA subjects, as well as the variation of epigenetic profiles in OSA patients after one year of high-adherence CPAP therapy. This case-control study includes 16 polysomnographically evaluated OSA patients and 8 controls. Blood samples were collected at initial visit (V1) and one year later (v2). Microarray data set consisted of n=48 microarrays, including one microarray per sample at visit 1 (n=24 arrays) and one microarray per sample at visit 2 (n=24 arrays). Microarray data was analyzed using Illumina Genome Studio v2011.1. Data was processed with background normalization.