Table 2

Sample characteristics by REM AHI severity category for incident systolic non-dipping (n=199)

REM AHI severity categoryTotal
<11–4.95–14.9≥15
N73603828199
Male, %4763668260
Age, years, mean (SD)46 (8)49 (7)50 (7)49 (9)48 (8)
Body mass index, kg/m2, mean (SD)27 (4)27 (4)30 (4)31 (5)28 (4)
Race/ethnicity, white, %99989510098
Current smoking, %1617182117
Alcohol, number of drinks/week (SD)4 (5)3 (5)5 (6)5 (6)4 (6)
Prevalent hypertension, %423135719
Type 2 diabetes, %00000
Waist-to-hip ratio, mean (SD)0.9 (0.1)0.9 (0.1)0.9 (0.1)1.0 (0.1)0.9 (0.1)
AHI, mean (SD)0.6 (1)3 (5)4 (3)18 (19)4 (9)
NREM AHI, mean (SD)0.7 (1)3 (6)3 (3)15 (20)4 (9)
REM AHI, mean (SD)0.2 (0.3)3 (1)8 (2)30 (13)7 (11)
Minutes total sleep time, mean (SD)393 (55)393 (54)371 (69)404 (66)391 (60)
Minutes REM sleep, mean (SD)76 (27)77 (28)70 (25)66 (25)74 (27)
Percent REM sleep, mean (SD)19 (6)19 (6)19 (5)16 (5)19 (6)
Minutes slow wave sleep, mean (SD)43 (29)45 (37)37 (31)36 (35)41 (33)
Percent slow wave sleep, mean (SD)11 (7)12 (9)9 (7)9 (9)11 (8)
Epworth Sleepiness Scale*, mean (SD)9 (4)9 (4)9 (3)12 (4)9 (4)
Excessive daytime sleepiness, %2612292122
  • *Only available on a subset of studies (n=110).

  • AHI, apnoea hypopnoea index; NREM, non-rapid eye movement; REM, rapid eye movement.