title: Effects of continuous positive airway pressure treatment on clinic and ambulatory blood pressures in patients with obstructive sleep apnea and resistant hypertension: a randomized controlled trial.
abstract: The effect of continuous positive airway pressure (CPAP) on blood pressures (BPs) in patients with resistant hypertension and obstructive sleep apnea is not established. We aimed to evaluate it in a randomized controlled clinical trial, with blinded assessment of outcomes. Four hundred thirty-four resistant hypertensive patients were screened and 117 patients with moderate/severe obstructive sleep apnea, defined by an apnea-hypopnea index ≥15 per hour, were randomized to 6-month CPAP treatment (57 patients) or no therapy (60 patients), while maintaining antihypertensive treatment. Clinic and 24-hour ambulatory BPs were obtained before and after 6-month treatment. Primary outcomes were changes in clinic and ambulatory BPs and in nocturnal BP fall patterns. Intention-to-treat and per-protocol (limited to those with uncontrolled ambulatory BPs) analyses were performed. Patients had mean (SD) 24-hour BP of 129(16)/75(12) mm Hg, and 59% had uncontrolled ambulatory BPs. Mean apnea-hypopnea index was 41 per hour and 58.5% had severe obstructive sleep apnea. On intention-to-treat analysis, there was no significant difference in any BP change, neither in nocturnal BP fall, between CPAP and control groups. The best effect of CPAP was on night-time systolic blood pressure in per-protocol analysis, with greater reduction of 4.7 mm Hg (95% confidence interval, -11.3 to +3.1 mm Hg; P=0.24) and an increase in nocturnal BP fall of 2.2% (95% confidence interval, -1.6% to +5.8%; P=0.25), in comparison with control group. In conclusion, CPAP treatment had no significant effect on clinic and ambulatory BPs in patients with resistant hypertension and moderate/severe obstructive sleep apnea, although a beneficial effect on night-time systolic blood pressure and on nocturnal BP fall might exist in patients with uncontrolled ambulatory BP levels.
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Muxfeldt
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Victor
authors.initials: V
authors.lastname: Margallo
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Leonardo M S
authors.initials: LM
authors.lastname: Costa
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Gleison
authors.initials: G
authors.lastname: Guimarães
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Aline H
authors.initials: AH
authors.lastname: Cavalcante
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: João C M
authors.initials: JC
authors.lastname: Azevedo
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Fabio
authors.initials: F
authors.lastname: de Souza
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Claudia R L
authors.initials: CR
authors.lastname: Cardoso
authors.affiliation: From the Department of Internal Medicine, University Hospital Clementino Fraga Filho, School of Medicine, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. gilsalles@hucff.ufrj.br.
authors.forename: Gil F
authors.initials: GF
authors.lastname: Salles
mesh_terms: D000368:Aged; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000502:physiology*; D018660:Blood Pressure Monitoring, Ambulatory / Q000379:methods*; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents
keywords: continuous positive airway pressure; obstructive sleep apnea; randomized controlled trial; resistant hypertension to conventional therapy