Baseline and follow-up BP of subjects by baseline OSA severity
| BP parameters | Normal | Primary snoring | Mild OSA | Moderate-to-severe OSA | P for trend* |
| n=98 | n=49 | n=75 | n=21 | ||
| Daytime SBP (mm Hg) | |||||
| Baseline† | 112±10 | 112±7 | 113±8 | 114±7 | 0.35 |
| ≥95th percentile, n (%) | 0 (0) | 0 (0) | 1 (1.7) | 0 (0) | 0.38 |
| Follow-up‡ | 115±9 | 116±10 | 117±10 | 118±8 | 0.076 |
| ≥135 mm Hg, n (%) | 1 (1.0) | 3 (6.1) | 3 (4.0) | 0 (0.0) | 0.59 |
| Daytime DBP (mm Hg) | |||||
| Baseline† | 71±6 | 73±6 | 72±6 | 73±4 | 0.20 |
| ≥95th percentile, n (%) | 1 (1.3%) | 2 (6.1) | 2 (3.4%) | 0 (0.0) | 0.81 |
| Follow-up‡ | 72±6 | 73±6 | 73±6 | 72±5 | 0.68 |
| ≥85 mm Hg, n (%) | 2 (2.0) | 3 (6.1) | 4 (5.3) | 0 (0.0) | 0.67 |
| Night-time SBP (mm Hg) | |||||
| Baseline† | 99±10 | 98±6 | 101±8 | 106±11§ | 0.011 |
| ≥95th percentile, n (%) | 10 (13.2) | 0 (0.0) | 6 (10.3) | 5 (29.4) | 0.36 |
| Follow-up‡ | 103±9 | 104±9 | 104±9 | 111±10§ | 0.007 |
| ≥120 mm Hg, n (%) | 3 (3.1) | 1 (2.0) | 4 (5.4) | 6 (28.6)§ | 0.001 |
| Night-time DBP (mm Hg) | |||||
| Baseline† | 59±6 | 58±5 | 59±5 | 62±6 | 0.19 |
| ≥95th percentile, n (%) | 12 (15.8) | 2 (6.1) | 8 (13.8) | 5 (29.4) | 0.47 |
| Follow-up‡ | 62±6 | 63±7 | 62±6 | 64±7 | 0.45 |
| ≥70 mm Hg, n (%) | 9 (9.3) | 8 (16.3) | 9 (12.2) | 2 (9.5) | 0.73 |
| Any hypertension, n (%) | |||||
| Baseline† | 17 (22.4) | 3 (9.1) | 12 (20.7) | 7 (41.2) | 0.33 |
| Follow-up‡ | 11 (11.3) | 11 (22.4) | 14 (18.9) | 6 (28.6) | 0.053 |
| SBP nocturnal dipping (%) | |||||
| Baseline† | 11.4±5.0 | 12.8±4.9 | 9.9±5.7 | 7.6±7.4§ | 0.009 |
| Follow-up‡ | 10.1±4.8 | 9.6±6.0 | 10.5±5.4 | 6.3±5.7§ | 0.15 |
| SBP non-dipping, n (%) | |||||
| Baseline† | 29 (38.2) | 9 (27.3) | 25 (43.1) | 11 (64.7) | 0.097 |
| Follow-up‡ | 53 (54.6) | 27 (55.1) | 35 (47.3) | 17 (81.0) | 0.48 |
| DBP nocturnal dipping (%) | |||||
| Baseline† | 17.3±6.7 | 19.7±7.4 | 17.8±5.8 | 15.8±7.2 | 0.78 |
| Follow-up‡ | 14.5±6.4 | 14.2±7.5 | 15.2±6.3 | 11.9±8.0 | 0.60 |
| DBP non-dipping, n (%) | |||||
| Baseline† | 10 (13.2) | 2 (6.1% | 6 (10.3) | 3 (17.6) | 0.97 |
| Follow-up‡ | 22 (22.7) | 16 (32.7) | 14 (18.9) | 7 (33.3) | 0.84 |
*P values obtained from linear contrast tests and linear-by-linear association tests for continuous and categorical data, respectively.
†59 missing.
‡2 missing.
§P <0.05 after Bonferroni adjustment, compared with the normal group.
BP, Blood Pressure; DBP, Diastolic Blood Pressure; OSA, Obstructive Sleep Apnoea; SBP, Systolic Blood Pressure.