Long-term effect of continuous positive airway pressure in hypertensive patients with sleep apnea.
BACKGROUND
Continuous positive airway pressure (CPAP) is the current treatment for patients with symptomatic obstructive sleep apnea (OSA). Its use for all subjects with sleep-disordered breathing, regardless of daytime symptoms, is unclear.


OBJECTIVE
This multicenter controlled trial assesses the effects of 1 year of CPAP treatment on blood pressure (BP) in nonsymptomatic, hypertensive patients with OSA.


METHODS
We evaluated 359 patients with OSA. Inclusion criteria consisted of an apnea-hypopnea index (AHI) greater than 19 hour(-1), an Epworth Sleepiness Scale score less than 11, and one of the following: under antihypertensive treatment or systolic blood pressure greater than 140 or diastolic blood pressure greater than 90 mm Hg. Patients were randomized to CPAP (n = 178) or to conservative treatment (n = 181). BP was evaluated at baseline and at 3, 6, and 12 months of follow-up.


RESULTS
Mean (SD) values were as follows: age, 56 +/- 10 years; body mass index (BMI), 32 +/- 5 kg x m(-2); AHI, 45 +/- 20 hour(-1); and Epworth Sleepiness Scale score, 7 +/- 3. After adjusting for follow-up time, baseline blood pressure values, AHI, time with arterial oxygen saturation less than 90%, and BMI, together with the change in BMI at follow-up, CPAP treatment decreased systolic blood pressure by 1.89 mm Hg (95% confidence interval: -3.90, 0.11 mm Hg; P = 0.0654), and diastolic blood pressure by 2.19 mm Hg (95% confidence interval: -3.46, -0.93 mm Hg; P = 0.0008). The most significant reduction in BP was in patients who used CPAP for more than 5.6 hours per night. CPAP compliance was related to AHI and the decrease in Epworth Sleepiness Scale score.


CONCLUSIONS
In nonsleepy hypertensive patients with OSA, CPAP treatment for 1 year is associated with a small decrease in BP. This effect is evident only in patients who use CPAP for more than 5.6 hours per night. Clinical trial registered with www.clinicaltrials.gov (NCT00127348).
Barbé
Ferran
F
Coordinating Center, Institut de Recerca Biomèdica Lleida, Lleida, Spain. fbarbe@arnau.scs.es
Durán-Cantolla
Joaquín
J
Capote
Francisco
F
de la Peña
Monica
M
Chiner
Eusebi
E
Masa
Juan F
JF
Gonzalez
Mónica
M
Marín
Jose M
JM
Garcia-Rio
Francisco
F
de Atauri
Josefa Diaz
JD
Terán
Joaquín
J
Mayos
Mercedes
M
Monasterio
Carmen
C
del Campo
Felix
F
Gomez
Sivia
S
de la Torre
Manuel Sanchez
MS
Martinez
Montse
M
Montserrat
José M
JM
D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D045422:Continuous Positive Airway Pressure / Q000379:methods*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D012720:Severity of Illness Index; D020181:Sleep Apnea, Obstructive / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D013997:Time Factors