Table 3.
Sleep heart rate variability indices in normal controls and in children and adolescents with OSA.
| Variable | Our study | Gasior's study (47) | Isaiah's study (14) | Muzumdar's study (17) | Nisbet's study (13) | Kirk's Study (48) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Publication year | 2020 | 2020 | 2011 | 2013 | 2020 | ||||||||
| Nation | Taiwan | Poland | USA | USA | Australia | Canada | |||||||
| Participants | OSA | NC | OSA | M-S OSA | Mild OSA | M-S OSA | OSA/obesity | ||||||
| Case number | 76 | 312 | 404 | 18 | 39 | 29 | 12 | ||||||
| Age (years) | 7.2 (2.1) | 10.1 (2.5) | 6.0 (4.5) | 4.9 (2.4) | 4.3 (0.1) | 4.2 (0.2) | 12.8 (5.1) | ||||||
| Male sex, n (%) | 59 (78) | 159 (51) | 195 (48) | 13 (72) | 26 (67) | 18 (62) | 10 (83) | ||||||
| OAHI (events/h) | 10.2 (12.6) | NA | 4.6 (4.6)* | 31.9 (24.8)* | 3.1 (0.9) | 15.5 (12.3) | 13.8 (14.5) | ||||||
| Sleep stage | FN | FN | FN | N1, N2 | N3 | REM | N1, N2 | N3 | REM | N1, N2 | N3 | REM | FN |
| Heart rate (bpm) | 77 (9) | NA | NA | 100 (17)a | 100 (15)a | 107 (16)a | NA | NA | 82 (7) | ||||
| N-N interval (ms) | 792 (97) | NA | NA | 630 (120)b | 620 (100)b | 580 (110)a | NA | NA | 732 (62) | ||||
| SDNN (ms) | 97 (33) | 54 (30) | 97 (37) | NA | NA | NA | 54 (25) | ||||||
| pNN50 (%) | 37 (19) | 34 (52) | 36 (24) | NA | NA | NA | NA | ||||||
| RMSSD (ms) | 76 (38) | 71 (91) | 81 (45) | 61 (55)b | 43 (29)b | 76 (57)b | NA | NA | NA | ||||
| Total power (ms2) | 10,460 (7,238) | 5,348 (9,534) | 8,838 (6,990) | NA | 7,632 (5,908) | 6,021 (6,145) | 5,287 (4,103) | 9,040 (5,905)a | 6,600 (6,144) | 5,827 (4,789)a | NA | ||
| VLF power (ms2) | 2,032 (2,284) | 171 (284) | 1,712 (1,186)a | NA | NA | NA | NA | ||||||
| LF power (ms2) | 1,727 (1,457) | 2,023 (3,789) | 1,382 (1,186) | 360 (342) | 184 (148)b | 307 (293) | 1,298 (1,024) | 758 (781) | 909 (606) | 1,959 (1,023)a | 848 (780) | 1,075 (603)a | NA |
| LF% (%) | 39 (15) | NA | NA | NA | NA | NA | 41 (17) | ||||||
| HF power (ms2) | 3,149 (3,029) | 3,766 (6,993) | 2,742 (3,340) | 902 (1,202)b | 483 (497)b | 412 (449)b | 4,418 (3,610)a | 3,985 (3,859) | 2,416 (2,186)a | 7,382 (3,608)a | 4,126 (3,856) | 2,183 (2,186) | NA |
| LF/HF ratio | 0.80 (0.66) | 0.72 (0.82) | 0.53 (0.36) | 1.60 (2.7)a | 1.20 (1.60)a | 3.0 (5.4)a | 0.70 (0.62) | 0.40 (0.25) | 1.10 (0.62) | 0.70 (0.54) | 0.30 (0.27)b | 0.90 (0.54) | 1.40 (1.18) |
To facilitate comparisons with previous studies, data are summarized as mean (standard deviation) after estimation from the sample size, median, and interquartile range.
aHigher than controls, P < 0.05; bLower than controls, P < 0.05.
*Only AHI was available.
AHI, apnea-hypopnea index; bpm, beats per min; FN, full night; HF, high frequency; LF, low frequency; LF%, normalized LF power; M-S, moderate-to-severe; N3, stage 3 sleep; NC, normal controls; N-N, normal-to-normal; pNN50, proportion of N-N50 divided by the total number of N-N intervals; RMSSD, square root of the mean of the sum of the squares of differences between adjacent N-N intervals; SDNN, standard deviation of all N-N intervals; VLF, very low frequency.