Hemodynamic phenotypes and its association with blood pressure changes at continuous positive airway pressure therapy in obstructive sleep apnoea hypertensive patients

Abstract

Background. The goal of our study was to define the hemodynamic phenotypes in hypertensive patients with newly diagnosed obstructive sleep apnoea (OSA) using the individual modelling of hemodynamics derived from ambulatory blood pressure monitoring (ABPM), a method proposed by our group previously, and to assess its validity in blood pressure alterations secondary to continuous positive airway pressure (CPAP). Material and methods. Thirty-three hypertensive patients with moderate-to-severe OSA were investigated. All patients underwent ABPM on two occasions: at baseline and after one week CPAP. The sets of BP indexes at first ABPM were used for individual modelling to define the hemodynamic phenotype (class) based on regression analyses; specifically, the phenotypes were defined for daytime, nighttime and for 24 hours. The CPAP therapy efficacy was predefined as improvement in BP nighttime decrease for additional 5% as compared to baseline ABPM. With reference to this criterion, patients were further classified as responders (who achieved this target), and non-responders. Results. Only 21.2% of hypertensive patients with OSA had optimal hemodynamic phenotype (class H2), despite comprehensive antihypertensive therapy; most of the other patients were classified either as harmonic type (class H3; 39.4%), or of diastolic dysfunctional type (class D3; 15.2%). In the daytime period 18.2% of patients with OSA were classified as D1-class, which is associated with high risk of acute hypotensive episodes. Responders were more frequently characterized by phenotype H3 (daytime) vs. nonresponders: 53.3% and 5.6% respectively; P < 0.05. At nighttime non-responders were more likely to transform the different baseline classes into H3 and D2; P < 0.05 vs. responders. Conclusion. Our study suggest utility of newly developed modelling based on hemodynamic BP indexes in the prediction of BP alterations secondary to CPAP in OSA hypertensive patients.