Table 2.
Distribution of select factors, by chronoscore, among nightshift workers included in the analysis of chronoscore in association with genome-wide DNA methylation as measured in blood
| Chronoscorea |
||
|---|---|---|
| Higher | Lower | |
| n (%) | n (%) | |
| Gender | ||
| Female | 53 (45) | 57 (47) |
| Male | 66 (55) | 65 (53) |
| Ageb,c | ||
| 22–28 | 31 (26) | 46 (38) |
| 29–34 | 24 (20) | 23 (19) |
| 35–41 | 27 (23) | 30 (24) |
| 40–55 | 37 (31) | 23 (19) |
| Body Mass Index [(lbs/in2)×703]b,d | ||
| 17.9–22.6 | 31 (26) | 30 (25) |
| >22.6–24.9 | 26 (22) | 34 (28) |
| >24.9–27.4 | 30 (25) | 30 (24) |
| >27.4–31.2 | 32 (27) | 28 (23) |
| Race | ||
| White | 83 (70) | 84 (70) |
| Other | 36 (30) | 37 (30) |
| Smoking | ||
| No | 115 (97) | 112 (92) |
| Yes | 4 ( 3 ) | 10 ( 8 ) |
| Alcohol | ||
| No | 106 (89) | 112 (92) |
| Yes | 13 (11) | 10 ( 8 ) |
| Months engaged in current shift schedule (months)e | ||
| 6-<12 | 20 (17) | 16 (13) |
| 12-<24 | 28 (23) | 36 (30) |
| 24-<54 | 28 (32) | 44 (36) |
| ≥ 54 | 33 (28) | 26 (21) |
| Proportion of blood cell types (means) | ||
| B-cells | 0.04 | 0.05 |
| CD8 T-cells | 0.09 | 0.09 |
| CD4 T-cells | 0.14 | 0.15 |
| Natural Killer cells | 0.06 | 0.04 |
| Granulocytes | 0.59 | 0.59 |
| Monocytes | 0.12 | 0.10 |
Score from the Composite Scale of Morningness was dichotomized at the midpoint of the scale; higher score (≥ 34) = mornigness; lower score (≤ 33) = eveningness
Age and BMI categories based on quartiles among all 241 participants included in chronoscore analysis.
Mean (Standard Deviation) for Age: Higher chronoscore = 36.1 (8.1); Lower chronoscore = 33.7 (8.4).
Mean (Standard Deviation) for Body Mass Index: Higher chronoscore = 25.0 (3.0); Lower chronoscore = 24.8 (2.8).
Mean (Standard Deviation) for Months engaged in current shift schedule: Higher chronoscore = 43.1 (43.7); Lower chronoscore = 40.1 (41.8).