Table 1.
Age-adjusted baseline (2005) characteristics by years of night shift work*
| Characteristic | Night shift work (years) |
|||
|---|---|---|---|---|
| Never | 1 - 2 | 3 - 9 | ≥10 | |
| Number of women | 17,722 | 5,791 | 3,149 | 1,379 |
| Mean age, years | 47.5 | 46.9 | 47.8 | 50.9 |
| Mean BMI, kg/m2 | 29.0 | 29.9 | 30.2 | 30.6 |
| Mean energy intake, kcal/day | 1,435 | 1,501 | 1,570 | 1,603 |
| Family history of diabetes, % | 34 | 36 | 37 | 41 |
| Current smokers, % | 9 | 12 | 14 | 13 |
| Current alcohol drinkers, % | 26 | 25 | 25 | 23 |
| Regular coffee consumption >1 cup/day, % | 8 | 9 | 11 | 11 |
| Decaf coffee consumption >1 cup/day, % | 2 | 2 | 2 | 1 |
| Regular soda consumption >1 cup/day, % | 5 | 6 | 7 | 9 |
| Diet soda consumption >1 cup/day, % | 2 | 1 | 2 | 2 |
| Education ≤12 years, % | 10 | 13 | 14 | 18 |
| Vigorous exercise ≥5 hours/week, % | 9 | 7 | 9 | 8 |
| Dietary patterns, % | ||||
| 5th quintile of vegetable/fruit (healthiest) | 20 | 19 | 18 | 18 |
| 5th quintile of meat/fried foods (unhealthiest) | 19 | 21 | 21 | 22 |
| Neighborhood socioeconomic status, % | ||||
| 1st quintile (poorest neighborhood) | 17 | 20 | 22 | 24 |
| 5th quintile (wealthiest neighborhood) | 21 | 16 | 14 | 12 |
*
All of the characteristics vary significantly across years of shift work categories at the alpha=0.05 level.