Table 1.
Baseline Characteristics of Participants by Category of SDB* (n=507)
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|
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|---|---|---|---|---|---|
| Category of SDB (events/hour) | |||||
|
| |||||
| Characteristic | Normal 0–4.9 (n=120) |
Mild 5.0–14.9 (n=182) |
Moderate 15.0–29.9 (n=130) |
Severe ≥30 (n=75) |
p value |
| Age, y, mean ± SD | 75.3 ± 5.0 | 76.0 ± 5.2 | 76.6 ± 5.4 | 76.2 ± 5.6 | 0.29 |
| Race, n (%) | 0.80 | ||||
| Caucasian | 113 (94) | 171 (94) | 125 (96) | 70 (93) | |
| Non-Caucasian | 7 (6) | 11 (6) | 5 (4) | 5 (7) | |
| BMI, kg/m2, mean ± SD | 26.3 ± 3.4 | 27.4 ± 3.6 | 28.1 ± 3.3 | 29.6 ± 4.5 | <0.001 |
| Smoking, n (%) | 0.88 | ||||
| Current | 3 (2.5) | 4 (2.2) | 3 (2.3) | 0 (0) | |
| Former | 71 (59) | 108 (59) | 81 (63) | 45 (60) | |
| Never | 46 (38) | 70 (39) | 45 (35) | 30 (40) | |
| Health status, n (%) | 0.04 | ||||
| Excellent/good | 109 (91) | 156 (86) | 118 (91) | 59 (79) | |
| Fair/poor/very poor | 11 (9) | 26 (14) | 12 (9) | 16 (21) | |
| Hypertension**, n (%) | 77 (64) | 123 (68) | 101 (78) | 58 (77) | 0.05 |
| Cardiovascular disease†, n (%) | 43 (36) | 74 (41) | 63 (49) | 31 (43) | 0.24 |
| Diabetes, n (%) | 11 (9) | 15 (8) | 22 (17) | 18 (24) | 0.002 |
| eGFR‡, mL/min per 1.73 m2, mean ± SD | 70.4 ± 13.6 | 70.7 ± 15.7 | 69.6 ± 15.3 | 67.9 ± 14.0 | 0.55 |
| ACR^, mg/g Cr, mean ± SD | 6.5 ± 2.2 | 7.5 ± 2.7 | 8.8 ± 2.8 | 9.4 ± 3.0 | 0.03 |
| Albuminuria^^, n (%) | 7 (6) | 16 (9) | 17 (13) | 11 (15) | 0.12 |
Sleep-disordered breathing (SDB) defined by Respiratory Disturbance Index (RDI) at ≥3% oxygen desaturation
Hypertension defined as any one of: self-reported hypertension, systolic blood pressure ≥140, diastolic blood pressure ≥90 or current use of at least one blood pressure medication (angiotensin-converting enzyme-inhibitor, angiotensin receptor-blocker, beta-blocker--non-opthalmic, thiazide, loop, or potassium-sparing diuretic, calcium-channel blocker, or alpha-blocker).
Cardiovascular disease defined as any one of: history of myocardial infarction, angina, congestive heart failure, transient ischemic attack, stroke, rheumatic heart disease, or cardiovascular surgery
Estimated glomerular filtration rate (eGFR) calculated by the 4-variable MDRD equation
Geometric mean albumin-to-creatinine ratio
Albuminuria defined as albumin-to-creatinine ratio (ACR) ≥30 mg/g Cr