Table 2.
Cognitive performance and sleepiness and mood questionnaires before and after 6 months of CPAP treatment
| Baseline | CPAP | Difference | Effect size | P | |
|---|---|---|---|---|---|
| Sleepiness and mood | |||||
| Epworth sleepiness scale(lower better) (n = 167) | 11.97 (4.90) | 7.67 (4.61) | −4.30 (−5.05 to −3.55) | 0.88 | <.0001 |
| DASS-depression(n = 162) | 11.10 (9.48) | 7.67 (9.68) | −3.43 (−4.69 to −2.17) | 0.36 | <.0001 |
| DASS-anxiety(n = 163) | 9.62 (8.18) | 6.90 (7.76) | −2.72 (−3.95 to −1.50) | 0.33 | <.0001 |
| DASS-stress(n = 163) | 13.93 (9.06) | 9.96 (8.34) | −3.96 (−5.21 to −2.72) | 0.44 | <.0001 |
| FOSQ total score(n = 148) | 14.78 (3.35) | 16.99 (2.92) | 2.21 (1.73 to 2.70) | 0.66 | <.0001 |
| Visuospatial scanning (letter cancellation task) | |||||
| Average hits(higher better) (n = 162) | 50.76 (13.00) | 55.11 (12.24) | 4.34 (3.28 to 5.40) | 0.33 | <.0001 |
| Average omissions(lower better) (n = 162) | 3.68 (5.23) | 3.31 (5.35) | −0.37 (−1.15 to 0.41) | 0.07 | .35 |
| Average commissions(lower better) (n = 162) | 0.97 (1.60) | 0.80 (1.56) | −0.17 (−0.43 to 0.1) | 0.11 | .21 |
| Hits final trial(higher better)* (n = 159) | 297.00 (17.0) | 297.00 (14.0) | 0.00 (9.00) | 0.00 | .93 |
| Omissions final trial(lower better)* (n = 159) | 13.00 (17.00) | 13.00 (14.00) | 0.00 (9.00) | 0.00 | .93 |
| Commissions final trial (lower better) (n = 159) | 4.15 (10.11) | 3.12 (4.86) | −1.03 (−2.46 to 0.40) | 0.10 | .16 |
| Duration final trial (s)(lower better) (n = 159) | 367.66 (164.83) | 320.12 (85.65) | −47.55 (−70.23 to −24.86) | 0.29 | <.0001 |
| Executive function (Stroop) | |||||
| Text accuracy (%)(higher better) % (n = 161) | 92.85 (17.39) | 96.02 (10.93) | 3.17 (0.02 to 6.31) | 0.18 | .049 |
| Text RT (sec)(lower better) (n = 161) | 1.28 (0.47) | 1.21 (0.35) | −0.08 (−0.14 to −0.01) | 0.17 | .02 |
| Colour accuracy (%)(higher better) (n = 160) | 79.68 (25.78) | 89.52 (21.92) | 9.84 (5.44 to 14.23) | 0.38 | <.0001 |
| Colour RT (s)(lower better) (n = 160) | 1.44 (0.58) | 1.28 (0.47) | −0.16 (−0.24 to −0.08) | 0.28 | <.0001 |
| Working memory (n-back) | |||||
| 2-Back accuracy NTGA (%)(higher better) (n = 162) | 0.65 (0.26) | 0.73 (0.26) | 0.08 (0.04 to 0.12) | 0.31 | <.0001 |
| 3-Back accuracy NTGA (%)(higher better) (n = 161) | 0.56 (0.24) | 0.65 (0.24) | 0.09 (0.06 to 0.13) | 0.38 | <.0001 |
| Sustained attention (psychomotor vigilance task) | |||||
| Mean RT(lower better) | 300.84 (76.98) | 286.15 (72.36) | −14.69 (−28.65 to −0.73) | 0.19 | .04 |
| Mean reciprocal RT(higher better) | 3.78 (0.56) | 3.90 (0.54) | 0.12 (0.03 to 0.21) | 0.21 | .009 |
| Mean fastest 10% RT(lower better) | 203.25 (26.08) | 200.19 (22.24) | −3.06 (−6.74 to 0.63) | 0.12 | .10 |
| Mean slowest 10% reciprocal RT(higher better) | 2.23 (0.64) | 2.50 (0.65) | 0.27 (0.14 to 0.40) | 0.42 | <.0001 |
| Lapses(lower better) | 4.30 (6.54) | 2.51 (4.42) | −1.80 (−2.89 to −0.70) | 0.28 | .002 |
Data are mean (standard deviation) and mean difference (95% CI) or median (IQR) and median difference (IQR) as indicated by a *. P values are calculated using paired t tests. DASS: Depression, Anxiety and Stress Scale; FOSQ: Functional Outcomes of Sleep Questionnaires; RT: reaction time. Bold values indicate p < 0.05.