Table 1.
Subject Characteristics and Polysomnography Parameters in OSA-PLMS and OSA-Only Group
| Internal Cohort | MrOS Study Cohort | |||||
|---|---|---|---|---|---|---|
| OSA-Only (N=625) | OSA-PLMS (N=95) | p | OSA-Only (N=922) | OSA-PLMS (N=1367) | p | |
| Clinical Characteristics | ||||||
| Age | 42 (35–53) | 61 (53–70) | <0.001 | 75 (71–79) | 76 (72–81) | <0.001 |
| Gender (male) | 534 (85%) | 79 (83%) | 0.7 | All Male | ||
| Ethnicity (white) | All Chinese | 800 (87%) | 1275 (93%) | <0.001 | ||
| BMI | 26.2 (24.2–28.3) | 26.0 (23.9–28.3) | >0.9 | 27 (25–30) | 27 (25–30) | 0.8 |
| ESS | 8.0 (5.0–12.0) | 9.0 (5.0–12.5) | 0.6 | 6 (3–8) | 6 (3–8) | 0.6 |
| Hypertension | 205 (33%) | 52 (55%) | <0.001 | 451 (49%) | 711 (52%) | 0.2 |
| Diabetes | 29 (4.6%) | 19 (20%) | <0.001 | 109 (12%) | 201 (15%) | 0.056 |
| Arrhythmia | 43 (6.9%) | 12 (13%) | 0.049 | 84 (9.1%) | 153 (11%) | 0.13 |
| Stroke | 47 (7.5%) | 20 (21%) | <0.001 | 29 (3.1%) | 50 (3.7%) | 0.6 |
| CAD | 8 (1.3%) | 2 (2.1%) | 0.6 | 143 (16%) | 268 (20%) | 0.014 |
| Asthma | 8 (1.3%) | 1 (1.1%) | >0.9 | 58 (6.3%) | 113 (8.3%) | 0.093 |
| COPD | 5 (0.8%) | 1 (1.1%) | 0.6 | 54 (5.9%) | 61 (4.5%) | 0.2 |
| PSG Parameters | ||||||
| TST, min | 429 (373–472) | 394 (314–455) | <0.001 | 364 (323–401) | 359 (315–400) | 0.057 |
| Sleep Efficiency, % | 87 (77–93) | 78 (63–85) | <0.001 | 77 (69–84) | 78 (69–85) | >0.9 |
| Sleep Latency, min | 4 (2–11) | 6 (1–16) | 0.3 | 17 (8–29) | 15 (8–28) | 0.6 |
| NREM 1, % | 13 (8–20) | 21 (13–36) | <0.001 | 6.0 (4.0–9.0) | 6.0 (4.0–9.0) | 0.7 |
| NREM 2, % | 51 (45–58) | 44 (34–53) | <0.001 | 62 (56–68) | 64 (57–70) | <0.001 |
| NREM 3, % | 15 (10–20) | 14 (5–20) | 0.072 | 11 (4–17) | 9 (3–15) | <0.001 |
| REM, % | 19 (15–23) | 17 (12–23) | 0.11 | 20 (15–24) | 19 (14–23) | 0.056 |
| ODI, N/hr | 20 (13–27) | 15 (6–33) | 0.026 | 20 (12–33) | 19 (12–31) | 0.2 |
| AHI, N/hr | 25 (15–34) | 21 (10–39) | 0.2 | 18 (10–30) | 16 (10–28) | 0.089 |
| AvgSaO2, % | 95 (95–96) | 95 (94–96) | 0.081 | 93 (74–95) | 93 (74–95) | 0.6 |
| MinSaO2, % | 81 (77–84) | 84 (77–87) | <0.001 | 84 (80–87) | 85 (81–88) | 0.057 |
| TS90, % | 2.8 (1.1–5.2) | 1.4 (0.2–8.3) | 0.10 | 1 (0–5) | 1 (0–4) | 0.048 |
| Arousal Index, N/hr | 16 (10–24) | 17 (8–28) | 0.5 | 21 (16–29) | 23 (17–32) | <0.001 |
Note: Values were expressed as median (interquartile range in brackets) or count (percentage).
Abbreviations: PLMS, periodic limb movement syndrome; OSA, obstructive sleep apnea; BMI, body mass index; ESS, Epworth Sleepiness Scale; CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; TST, total sleep time; NREM, non-rapid eye movement; REM, rapid eye movement; ODI, oxygen desaturation index; AHI, apnea-hypopnea index; avgSaO₂, mean arterial oxygen saturation; minSaO₂, lowest arterial oxygen saturation; TS90, percentage of total sleep time at oxygen saturation level < 90%.