| Ballester et al., 1999(26) |
No age criteria/ 53 ± 10 SE |
105 (CPAP 68; Cons. Tx 37) |
56 ± 20 |
Conservative Tx (weight loss, sleep hygiene)/3 mo |
CPAP > 4.5 h/night |
Significant differences subjective sleepiness, self-reported symptoms, day time function. |
| Barbé et al., 2001(27) |
No age criteria/ 54 ± 2 SE (CPAP); 52 ± 2 SE (Sham CPAP) |
55 (29 CPAP; 25 Sham) |
CPAP 54 ± 3 SE; Sham CPAP 57 ± 4 SE |
Sham-CPAP /6 wks |
CPAP 5 ± 0.4 h/day; Sham-CPAP 4 ± 0.5h/day |
No statistical difference between interventions for 24 hr blood pressure, quality of life; subjective and objective sleepiness, neurobehavioral battery except one of four addition tasks. |
| Barnes et al., 2002(19) |
> 18 years/45.5 ± 10.7 SE |
42(28) |
12.9 ± 6.3 |
Tablet placebo/8 wks |
CPAP 3.53±2.13 h |
Active CPAP treatment was superior to placebo for self-reported symptoms, but not for subjective and objective sleepiness, memory, cognitive processing, executive function, sustained attention, mood, or quality of life. |
| Barnes et al., 2004(20) |
No age criteria/47 + 0.9 SD |
104 (80 completed all 3 tx arms-placebo, or alappliance, CPAP) |
21.3 + 1.3 |
Tablet placebo/3mo |
CPAP 3.6 ± 0.3 h/night |
Compared to placebo, CPAP improved AHI and hypoxemia; reduction in stage 1sleep and increase stage 3 & 4 sleep subjective sleepiness; self-reported symptoms; sustained attention, mood; quality of life, and cognitive processing. No improvement in objective sleepiness, some neurobehavioral tests, or blood pressure |
| Becker et al., 2003(28) |
No age criteria/CPAP 54.4 ± 8.9 SD, Subtherapeutic CPAP 52.3 ± 8.4 |
60(32, 16each tx arm) |
CPAP=62.5 ±17.8; Subtherapeutic CPAP =65.0 ± 26.7; Therapeutic=65.2 ± 17.8 |
Subtherapeutic CPAP (lowest pressure setting of device used)/9 wks |
CPAP 5.5 ± 2.0 h/night;Subtherapeutic 5.4 ± 2.2 h/night |
Greater change from baseline with active vs. subtherapeutic CPAP in: mean arterial blood pressure; mean systolic and diastolic; mean daytime BP; daytime diastolic; mean nighttime BP, mean night time diastolic, AHI, subjective sleepiness, mean SaO2. There was no significant change in mean daytime and nighttime systolic pressure, total sleep time, or increases in percentage of sleep stages. |
| Chong et al., in press(29) |
Not stated/78 (53-91) CPAP 77.68 ± 6.9 SD ; Sham CPAP 77.85 ± 7.3 |
39 |
28.5 ± 17.2/CPAP 30.7 ± 17.8; Sham CPAP 26.4 ± 16.6 |
Sham CPAP 0 - 0.5 cm H2O/3 wk |
CPAP 5.2 ± 2 h/night |
Active CPAP was more effective than sham CPAP in reducing the RDI and subjective sleepiness |
| Engleman et al., 1994(21) |
No agecriteria/49±1.5 SE |
35 (32) |
Median AHI 28 (7 – 129/h) |
Tablet placebo/4 wk |
CPAP 3.4 ± 0.4 SE |
Compared to placebo, CPAP improved self-reported symptoms; objective sleepiness; mood; quality of life; energetic arousal. There was no significant difference in cognitive processing. |
| Engleman et al., 1997(22) |
No age criteria/52 ± 2 SE |
18(16) |
11 ± 1 |
Tablet placebo/4 wk |
CPAP 2.8 ± 0.6 SE hours per night |
CPAP was more effective than placebo for the outcomes: self-reported symptoms; executive function; and depressed mood. No significant change was noted for objective and subjective sleepiness, sustained attention, perceived general health, and quality of life |
| Engleman et al, 1998(23) |
No age criteria/47 ± 12 SD |
23(23) |
43 ± 37 |
Tablet placebo/4 wk |
CPAP 2.8 ± 2.0 SD hrs/night |
Compared to placebo, CPAP superior for objective sleepiness; subjective sleepiness; self-reported symptoms. No significant difference was observed for neurobehavioral performance, mood, and quality of life. |
| Engleman et al., 1999(44) |
No age criteria/44 ± 8 SD yrs |
37(34) |
10 ± 3 |
Tablet placebo/4 wk |
CPAP 2.8 ± 2.1 hr/night |
Compared to baseline, CPAP was superior to placebo for self-reported symptoms; subjective sleepiness; cognitive processing; depressed mood; and health status/functional status. No statistically robust change for objective sleepiness, and executive functioning, |
| Faccenda et al., 2001(24) |
No age criteria/median 50(29-72) |
71(68) |
median 35(15-129) |
Tablet placebo/4 wk |
CPAP 3.3 hr/night (range:0-8.1 hr |
CPAP produced significantly greater changes in diastolic (but not systolic or mean arterial pressure); subjective sleepiness; and functional status |
| Hack et al., 2000(30) |
Between ages 30 – 75 years/CPAP 50 (38 –68); Sham CPAP 50 (35 – 64) |
69(59) |
CPAP 26.1 (12.6 – 55.5); Subtherapeutic CPAP 34.7 (11 – 70) |
Sub therapeutic CPAP delivering 0.5 - 1 cm H2O/ 1 mo |
Active CPAP median 5.6 (3.0 – 7.2) h/night; Sub-therapeutic 5(1.2 – 8.5) h/night; |
Significance pre/post differencesubtherapeutic vs. active CPAP intracking; sustained attention; subjectiveand objective sleepiness, but not reaction time. |
| Henke, et al., 2001(31) |
No age criteria/CPAP 50.2 ± 10.4 SD; Sham CPAP 50.6 ± 9.7 SD |
45(39) |
CPAP 62.1 ± 27.4 SD; Sham CPAP 68.1 ± 25.2 SD |
16 days ActiveC PAP pressure vs.14 days Sub-therapeutic CPAP (0-1 cm H2O) |
CPAP 5.9 ± 1.8 SD h/day ; sham-CPAP5.2 ± 2.2 SD h |
No differences between the two interventions for neurobehavior or subjective sleepiness. |
| Jenkinson et al., 1999(32) |
Between 30 – 75 years of age/CPAP 50 (33-71); Sham CPAP – median 48 (36-68) |
107 (101) |
> 4% SaO2 CPAP 32.9 (15.5-64.4); Sham CPAP 28.5(10.7-68.7) |
Subtherapeutic CPAP (1 cm H2O)/4 wk |
CPAP – median 5.4 hrs/night; Subtherapeutic CPAP 4.6 hrs/night |
Significant pre/post between CPAP and subtherapeutic for subjective and objective sleepiness; oxygen saturation; and health status |
| Kajaste et al., 2004(40) |
No age criteria/CPAP 50.1 ± 7.9SD, wt. loss 47.9 ± 8 |
33(31) |
ODI 4CPAP 47.9±33.5 SD; wt. loss 55.5 ± 28.5 |
Very low calorie diet and cognitive behavioral therapy/24 mo |
CPAP every night by self-report |
No significant difference between interventions for ODI4 values or emotional well-being |
| McArdle et al., 2001(25) |
No age criteria/53 ± 11 SD |
23(22) |
median 40 (IQR 25-65) |
Tablet placebo/4 wk |
median CPAP use 4.5 (IQR 2.6-6.2) h/night |
Significant differences CPAP vs. placebo in sleep architecture (less stage 1; increased stage 3+4); self-reported feeling of being more refreshed; subjective sleepiness |
| Monasterio et al., 2001(41) |
No age criteria/54 ± 9 SD |
142 (125) |
CPAP 20 ± 6;conservative tx 21 ± 6 |
Conservative measures (weight loss [home diet if BMI >27]; sleep hygiene)/6 mo |
4.8 ± 2.2 h/d |
Significant differences between cons tx vs. CPAP intervention for self-reported symptoms at 3 & 6 mo; memory at 3 mo; executive function at 3 mo. No significant differences noted for subjective and objective sleepiness, vigilance, daily functioning, or quality of life. |
| Montserrat et al., 2001(33) |
No age criteria/54.2 ± 10.2 SD CPAP 55.65 ± 9.41 (28-74) Sham CPAP 52.59 ± 10.93 |
48(45) |
53.8 ± 19.3/CPAP 50.52 ± 19.83; Sham CPAP 57.14 ± 21.14 |
Sham CPAP |
Active CPAP 4.25 ± 2; Sham CPAP 4.5 ±2 |
Greater improvement was demonstrated for subjective sleepiness; self-reported symptoms; functional status, but not for perceived health status. |
| Nelesen et al., 2001(34) |
No age criteria/50 ± 2.2 SE |
41/CPAP 23; Sham CPAP 18 |
39 ± 4.7 SE |
Sham CPAP 2 cm H2O/8 days |
Active CPAP 6± 0.2; Sham CPAP6± 0.2 |
Compared to placebo, active CPAP produced significant lowering of lower heart rate; greater high frequency power; increased respiratory sinus arrhythmia; improvement in cardiac contractility, and stroke volume. In response to a stressor, the CPAP treated group compared to placebo had lower sinus arrhythmia; higher cardiac acceleration index preejection period, low frequency/high frequency ratio; lower systemic vascular resistance; and higher cardiac output. No significant differences in mean arterial blood pressure |
| Pepperell et al., 2002(35) |
30 – 75 yrs /CPAP 50.1 ± 10.4 SD; Subtherapeutic CPAP 51.0 ± 9.8 |
137 (104) |
>4% oxygen saturation dips/h sleep CPAP 38± 19.8; Subtherapeutic 35.9 ± 19.6 |
Subtherapeutic CPAP < 1 cm H20/4 wk |
Active CPAP 4.9 ± 2.0; Subtherapeutic CPAP 4.5 ± 2.4 |
Significant differences in change from baseline between treatments in 24-h mean blood pressure; sleep period mean blood pressure; wake period mean blood pressure; overall systolic blood pressure; overall diastolic blood pressure |
| Profant et al., 2003( 36) |
30-65/ CPAP 47.7 ± 8.1 SD; Sham CPAP 48.7 ± 9.9 |
39 |
CPAP 53.6 ± 23.2; Sham CPAP 41.7 ± 25.6 |
Sham CPAP ≤ 2cm H2O/7 days |
> 5 hr/night for each group |
Active treatment significant reduced RDI, but not quality of life. |
| Redline et al., 1998(37) |
25 -65/ 48 ± 9.8 SD |
114 (97) |
13.3 ± 9.8 |
Conservative tx (mechanical nasaldilators)/CPAP10.8 ± 2.7 wk; conservative tx 10.1 ± 1.8 wk |
Nasal dilator self-reported use 82 ± 26%of intervention nights; Mean CPAP use 3.1 h/night |
Significant differences between cons tx and CPAP were change from baseline in: RDI; oxygen saturation nadir; subjective sleepiness, and functional status. No change in objective sleepiness. |
| Robinson et al., 2004(42) |
30 – 75 yrs/subtherapeutic CPAP group 49.1 ± 10.3 SD; therapeutic CPAP 49.7 ± 10.3 yrs |
220 (112 subtherapeutic CPAP; 108 therapeutic CPAP |
Oxygen desaturation dips >4%/hr sleep subtherapeutic = 38.5 ± 20.3; therapeutic CPAP 38.9 ± 21.1 |
Subtherapeutic CPAP < 1 cm H20/4 wk |
Subtherapeutic CPAP = 4.1 ± 2.4; therapeutic CPAP 5.0 ± 1.9 h/night |
Levels of coagulation factors VII a and XII fell in the sub therapeutic but not therapeutic CPAP group. There were no differences between the groups in factor XIIa, soluble P-selectin or thrombin-antithrombin complex. There were no differences between the groups for cholesterol and triglyceride. |
| Robinson et al., 2006(43) |
> 18 yrs/54 ± 8 SD yrs |
35 (32; 16 subtherapeutic CPAP; 16 therapeutic CPAP) |
Median oxygen desaturation dips >4%/hr sleep = 28.1 (IQ 18.0 – 38.0) |
Subtherapeutic CPAP < 1 cm H20/4 wk |
Subtherapeutic CPAP = 4.3 ± 2.4 ;therapeutic CPAP 5.2 ± 2.1 h/night |
No differences between groups for 24 h mean blood pressure, daytime or sleep time blood pressure, 24 h systolic or diastolic pressure. |
| Zhang et al., 2003(38) |
No age criteria/OSA 63.4 ± 4 SD (60 – 74); Controls 63.8 (60 – 73) |
41 (32 healthy controls) |
37 ± 9.6 |
Healthy normal controls without OSA or cardiocerebral disease |
Not stated |
After CPAP tx, compared to healthy controls, there was no difference at 6 AM or 4 PM in hematocrit, whole blood viscosity, platelet aggregation, blood coagulability and fibrinogen. |
| Ziegler et al., 2001(39) |
35-64/CPAP 48.3 ± 1.4 SE; Sham CPAP 49.7 ± 2.2 |
38 |
CPAP 54 ± 5; Sham CPAP 39 ±5 |
Sham CPAP < 2cm H2O/ 10 days |
Not reported |
Compared to placebo, CPAP significantly lowered RDI; daytime, but not nighttime, heart rate; decreased plasma and daytime, but not nighttime urine norepinephrine levels; increased beta2-adrenergic-receptor sensitivity. There were no differences in epinephrine responses, beta-receptor density, or alpha-receptor sensitivity.. |
