Table 1.
Baseline Characteristics of Cohort Studies, Including the MESA and the SHHS
| MESA (N = 1,395) | SHHS (N = 4,575) | |
|---|---|---|
| Age, yr | 68.5 (9.12) | 64.2 (11.0) |
| Race | ||
| White | 519 (37.2%) | 4,029 (88.1%) |
| Black | 355 (25.4%) | 272 (5.95%) |
| Chinese | 172 (12.3%) | — |
| Hispanic | 349 (25.0%) | — |
| Other | — | 274 (5.99) |
| Sex, M | 663 (47.5%) | 2,183 (47.7%) |
| BMI, kg/m2 | 28.8 (5.49) | 28.3 (5.03) |
| Smoking | ||
| Never | 645 (46.4%) | 2,121 (46.4%) |
| Current | 96 (6.90%) | 420 (9.18%) |
| Former | 650 (46.7%) | 2,034 (44.5%) |
| Diabetes | 159 (11.4%) | 346 (7.56%) |
| Hypertension | 794 (56.9%) | 1,867 (40.8%) |
| Lipid-lowering medications | 536 (38.4%) | 583 (12.7%) |
| Baseline CVD | 91 (6.55%) | 751 (16.4%) |
| β-Adrenergic blockers | 250 (17.9%) | 564 (12.3%) |
| Systolic blood pressure, mm Hg* | 123 (20.2) | 125 (18.4) |
| Diastolic blood pressure, mm Hg* | 68.5 (9.73) | 72.0 (10.9) |
| Total sleep time, min | 365 (78.1) | 364 (62.7) |
| AHI, events/h | 19.3 (10.7–33.1) | 14.1 (7.65–24.4) |
| SpO2 < 90%, % of total sleep time | 0.76 (0.07–3.44) | 0.24 (0.00–2.06) |
| Event-related minimum HR, BPM | 60.4 (8.89) | 61.9 (8.74) |
| ΔHR categories† | ||
| Midrange | 697 (50.0%) | 2,288 (50.0%) |
| Low | 349 (25.0%) | 1,736 (37.9%) |
| High | 349 (25.0%) | 551 (12.0%) |
Definition of abbreviations: AHI = apnea–hypopnea index (all apneas and hypopneas associated with ⩾3% desaturation or arousal); BMI = body mass index; BPM = beats per minute; CVD = cardiovascular disease; ΔHR = HR response to apneas/hypopneas; HR = pulse rate; MESA = Multi-Ethnic Study of Atherosclerosis; SHHS = Sleep Heart Health Study; SpO2 = oxygen saturation as measured by pulse oximetry.
Average values are the mean (SD), n (%), or median (interquartile range).
*
Mean of two measurements in the MESA and SHHS.
†
Cutoffs in the MESA and SHHS are based on quartiles of the ΔHR in the MESA cohort.