Table 2. The relationship between telomere length (z score), rotating night shifts, and sleep duration.
| n | Mean±SEa (z score) | P for trend a | Mean±SEb (z score) | P for trend b | |
| Rotating night shifts(years) | |||||
| Never | 1583 | −0.007±0.03 | 0.28 | −0.008±0.03 | 0.36 |
| 1–2 | 965 | 0.04±0.03 | 0.04±0.03 | ||
| 3–5 | 669 | 0.004±0.04 | −0.003±0.04 | ||
| 6–9 | 304 | 0.03±0.06 | 0.03±0.06 | ||
| 10–19 | 305 | −0.07±0.06 | −0.06±0.06 | ||
| ≥20 | 166 | −0.05±0.08 | −0.05±0.08 | ||
| Sleep duration (hours) | |||||
| ≤6 | 1026 | −0.04±0.03 | 0.06c | −0.05±0.03 | 0.05c |
| 7 | 1703 | 0.007±0.02 | 0.01±0.02 | ||
| 8 | 948 | 0.03±0.03 | 0.02±0.03 | ||
| 9 | 167 | 0.07±0.08 | 0.07±0.08 | ||
| ≥10 | 19 | −0.04±0.23 | −0.1±0.23 | ||
a
Adjusted for age (continuous variable).
b
Adjusted for age (continuous variable), BMI (continuous variable), and cigarette smoking (pack years).
c
P for trend from sleep duration ≤6 hours to 9 hours.