Home Blood Pressure Trajectories During 6 Months Of Continuous Positive Airway Pressure Therapy

<bold>Background:</bold> Obstructive Sleep Apnea (OSA) and hypertension are common comorbidities and are associated with poor prognosis. Blood pressure (BP) trajectories using home BP monitoring (HBPM) after initiation of Continuous Positive Airway Pressure (CPAP) therapy for OSA have been poorly documented. <bold>Aims and objectives:</bold> In a prospective cohort of patients with OSA initiated on CPAP, we aimed: to describe BP trajectories in the first 6 months after CPAP therapy initiation based on repeated longitudinal measurements of home BP; to evaluate the impact of CPAP on morning and evening BP; to identify predictors of BP evolution under CPAP. <bold>Methods:</bold> This prospective cohort study enrolled patient with OSA. HBPM was used to assess morning and evening home BP values over a 7-day period at baseline, and over the first 6 months after starting CPAP therapy. <bold>Results:</bold> 98 patients were enrolled and 36,600 home BP measurements were available for analysis. Morning and evening systolic and diastolic BP decreased significantly during the first 6 months of CPAP therapy (p<0.05 vs. baseline). Morning BP was significantly higher than evening BP throughout the study (p < 0.01). After adjustment for OSA severity at baseline and CPAP adherence, older age, weight gain during CPAP therapy, current smoking and previous hypertension were associated with limited BP response to CPAP. <bold>Conclusion:</bold> CPAP improved home BP trajectories during the first 6 months but the response was heterogeneous and less marked for morning BP values. Based on the predictors of BP response during CPAP therapy, weight control appears key to the effective management of patients with OSA and hypertension.