Table 1.
Study characteristics by quintiles of baseline LAN in 464,371 participants in the NIH-AARP Diet and Health Study.
| LAN in 1996 | |||||
|---|---|---|---|---|---|
| Q1 | Q2 | Q3 | Q4 | Q5 | |
| LAN, nW/cm2/sr, median (IQR) | 5.3 (3.2, 7.6) | 14.2 (11.8, 17.0) | 27.1 (23.5, 30.9) | 44.6 (39.7, 49.9) | 74.2 (64.8, 88.0) |
| Female, % | 36.4 | 37.2 | 38.3 | 40.8 | 44.5 |
| Age, year, mean (SD) | 62.1 (5.3) | 62.0 (5.4) | 61.9 (5.4) | 62.2 (5.3) | 61.9 (5.4) |
| White, non-Hispanic, % | 96.6 | 95.1 | 93.8 | 92.7 | 83.4 |
| College and post college, % | 33.3 | 39.4 | 42.9 | 42.0 | 36.6 |
| Married, % | 77.3 | 73.3 | 70.7 | 67.1 | 58.4 |
| Current smoker, % | 11.7 | 11.5 | 11.5 | 11.6 | 13.1 |
| Former smoker, % | 34.6 | 34.9 | 35.2 | 35.3 | 34.9 |
| Health Eating Index-2005, mean (SD) | 66.2 (11.4) | 66.6 (11.4) | 66.9 (11.4) | 62.1 (5.4) | 66.7 (11.6) |
| Fruit and vegetable consumption, servings/1,000 kcal, mean (SD) | 3.79 (1.76) | 3.87 (1.79) | 3.93 (1.82) | 3.97 (1.86) | 4.05 (1.97) |
| Vigorous physical activity, 5 or more times/week, % | 20.7 | 19.9 | 19.2 | 18.8 | 17.3 |
| Body-mass index, kg/m2, mean (SD) | 27.1 (4.9) | 27.1 (4.9) | 27.0 (5.0) | 27.0 (5.1) | 27.1 (5.4) |
| Sleep, 7–8 hours/night, % | 64.6 | 63.0 | 62.4 | 61.3 | 56.7 |
| Alcohol consumption, 1–3 drinks/day, % | 33.7 | 35.7 | 36.5 | 37.3 | 38.6 |
| Census tract median home value, 1kUSD, mean (SD) | 147 (115) | 181 (151) | 204 (153) | 204 (143) | 188 (139) |
| Census tract poverty rate, percentage, mean (SD) | 8.8 (6.0) | 7.2 (6.0) | 6.9 (6.1) | 7.5 (6.3) | 10.9 (8.5) |
| Census tract population density, per km2, mean (SD) | 298 (421) | 894 (752) | 1,425 (1,094) | 2,019 (1,425) | 3,743 (3,281) |
| Metropolitan countiesa, % | 77.8 | 94.8 | 99.0 | 99.9 | 100.0 |
| Chronic conditions | |||||
| Diabetes | 8.9 | 8.8 | 8.7 | 8.8 | 10.1 |
| Heart Disease | 14.5 | 14.1 | 13.7 | 13.6 | 13.3 |
| Stroke | 2.3 | 2.2 | 2.0 | 2.1 | 2.2 |
a
Metro status of counties was determined by the Office of Management and Budget using the 1993 Rural-Urban Continuum Codes.
Abbreviations: LAN, light at night; IQR, interquartile range; SD, standard deviation.