Table 2.
BMI and Sleep Characteristics from Age 3 to 6 Years
| Age 3 | Age 4 | Age 5 | Age 6 | |
|---|---|---|---|---|
| All (n = 301) | ||||
| BMI percentile (%) | 61.1 ± 27.0 | 63.1 ± 26.7 | 65.1 ± 26.7 | 66.6 ± 26.2 |
| Total sleep durationa (hours) | 11.2 (9.7–13.4) | 10.7 (8.9–12.9) | 10.7 (8.1–12.7) | 10.5 (8.3–12.6) |
| Daytime naps (minutes) | 40.0 (26.2–52.5) | 30.0 (20.0–45.0) | 35.0 (20.0–60.0) | 0 (0–0) |
| Nighttime sleep duration (hours) | 10.6 (8.7–12.6) | 10.7 (8.2–12.9) | 10.6 (8.1–12.7) | 10.5 (8.3–12.6) |
| Bedtime | 21:31 (18:47–01:25) | 21:27 (19:31–0:48) | 21:21 (19:24–0:19) | 21:26 (19:53–0:28) |
| Wake time | 8:07 (6:08–12:10) | 8:07 (5:38–11:23) | 7:58 (6:01–10:31) | 7:52 (6:07–10:43) |
| Boys (n = 153) | ||||
| BMI percentile (%) | 60.5 ± 26.9 | 62.4 ± 26.6 | 64.5 ± 26.7 | 66.4 ± 26.2 |
| Total sleep durationa (hours) | 11.2 (9.7–13.3) | 10.7 (8.9–12.9) | 10.7 (8.8–12.7) | 10.5 (8.8–12.6) |
| Daytime naps (minutes) | 38.3 (25.0–51.7) | 28.3 (18.3–40.0) | 37.5 (22.5–50.0) | 0 (0–0) |
| Nighttime sleep duration (hours) | 10.6 (8.7–12.6) | 10.7 (8.9–12.9) | 10.7 (8.8–12.7) | 10.5 (8.8–12.6) |
| Bedtime | 21:29 (18:47–01:25) | 21:26 (19:31–0:48) | 21:19 (19:25–23:34) | 21:25 (19:53–0:01) |
| Wake time | 8:08 (6:08–12:10) | 8:05 (6:25–11:19) | 7:58 (6:30–10:07) | 7:52 (6:11–10:01) |
| Girls (n = 148) | ||||
| BMI percentile (%) | 61.6 ± 27.2 | 63.8 ± 27.0 | 65.8 ± 26.7 | 66.7 ± 26.3 |
| Total sleep durationa (hours) | 11.2 (9.7–13.4) | 10.8 (9.0–12.9) | 10.6 (8.1–12.5) | 10.4 (8.3–11.9) |
| Daytime naps (minutes) | 42.5 (26.7–53.3) | 37.1 (20.0–47.5) | 35.0 (20.0–60.0) | 0 (0–0) |
| Nighttime sleep duration (hours) | 10.5 (8.8–12.6) | 10.7 (8.2–12.9) | 10.6 (8.1–12.5) | 10.4 (8.3–11.9) |
| Bedtime | 21:32 (19:45–23:40) | 21:28 (19:33–0:15) | 21:25 (19:59–0:19) | 21:28 (20:00–24:28) |
| Wake time | 8:04 (6:16–10:35) | 8:08 (5:38–11:23) | 7:58 (6:01–10:30) | 7:53 (6:07–10:43) |
Minutes of daytime naps are summarized using median (IQR). Data include mean ± SD, mean (min–max), or median (IQR).
a
Total sleep duration includes nighttime sleep duration plus daytime nap duration.
IQR, interquartile range; SD, standard deviation.