Trajectories of Home Blood Pressure Monitoring During the First 6 Months of Continuous Positive Airway Pressure Therapy in Patients With Obstructive Sleep Apnea

Abstract Rationale: The combination of Obstructive Sleep Apnea (OSA) and hypertension is a frequent comorbid association at poor prognosis. Trajectories of blood pressure (BP) after initiation of Continuous Positive Airway Pressure (CPAP), the first line therapy for OSA have been poorly documented by multiple points longitudinal measurements of home BP monitoring (HBPM). In a prospective cohort of patients with OSA initiated on CPAP, we aimed: (i) To describe trajectories of BP in the first 6 months of CPAP therapy by collecting repeated longitudinal measurements of HBPM; (ii) To evaluate the specific impact of CPAP on morning and evening blood pressures; (iii) To identify the modulators of blood pressure evolution under CPAP. Methods: 98 OSA patients were assessed over a 7-day period with home self-measurement of morning and evening blood pressures to characterize baseline BP values before treatment. OSA patients were then initiated on CPAP and morning and evening systolic and diastolic BP measurements were collected over the first 6 months of CPAP treatment. Results: 36,600 HBPM measurements were available for analysis.When depicting HBPM trajectories, a significant BP reduction was observed across the six months of CPAP therapy for evening and morning systolic and diastolic BP measurements (p<0.05). Morning HBPM measurements remained significantly higher than evening measurements during CPAP use (p < 0.01). After adjustment for OSA severity at baseline and CPAP adherence, older age, weight gain under CPAP, current smoking and previous hypertension were associated with limited response to CPAP. Conclusion: CPAP is improving trajectories of blood pressure, but the response is heterogeneous and more limited for morning BP values. Associated weight control is key in the management of these multimorbid patients.