Table 1.
Age-Standardized Baseline Characteristics of Participants According to Frequency of Aspirin Use, Nurses' Health Study II, 1995a
| Frequency of Aspirin Use, days/week |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| <1 (n = 32,780) |
1 (n = 9,333) |
2–3 (n = 2,595) |
4–5 (n = 720) |
≥6 (n = 1,616) |
||||||
| Mean (SD) | % | Mean (SD) | % | Mean (SD) | % | Mean (SD) | % | Mean (SD) | % | |
| Age, yearsb | 39.8 (4.7) | 40.8 (4.4) | 41.6 (4.3) | 42.0 (4.2) | 42.8 (4.0) | |||||
| Body mass indexc | 25.5 (5.8) | 25.4 (5.7) | 25.9 (6.1) | 26.5 (6.5) | 26.8 (6.8) | |||||
| Physical activityd in 1997, METs | 18.4 (22.3) | 19.4 (23.4) | 18.7 (21.5) | 16.9 (19.2) | 19.6 (23.6) | |||||
| Smoking status | ||||||||||
| Never smoker | 68.5 | 64.8 | 63.1 | 61.4 | 62.5 | |||||
| Past smoker | 22.6 | 24.6 | 25.6 | 25.6 | 23.7 | |||||
| Current smoker, cigarettes/day | ||||||||||
| 1–4 | 1.7 | 2.3 | 2.2 | 1.7 | 1.8 | |||||
| 5–14 | 2.7 | 3.3 | 3.1 | 4.4 | 4.3 | |||||
| ≥15 | 4.4 | 4.9 | 5.9 | 7.0 | 7.6 | |||||
| Alcohol consumption, g/day | 3.2 (6.1) | 4.4 (7.6) | 4.8 (8.2) | 4.3 (7.2) | 3.7 (7.9) | |||||
| Daily nutrient intake | ||||||||||
| Vitamin B12, µg | 9.9 (14.4) | 10.0 (13.5) | 9.8 (11.5) | 12.3 (22.5) | 11.5 (14.5) | |||||
| Folate, µg | 463.0 (284.4) | 447.0 (250.4) | 448.0 (243.3) | 484.9 (264.9) | 529.3 (312.2) | |||||
| Potassium, mg | 3,113.3 (640.1) | 3,125.5 (625.9) | 3,110.1 (635.5) | 3,085.3 (669.4) | 3,188.4 (715.2) | |||||
| Magnesium, mg | 332.5 (87.3) | 335.4 (83.0) | 332.8 (77.5) | 334.7 (91.9) | 347.1 (105.4) | |||||
| Vitamin A, IU | 14,327 (10,037) | 14,306 (9,682) | 14,313 (9,796) | 15,557 (12,177) | 16,345 (11,661) | |||||
| History of hypertension | 8.4 | 8.5 | 11.0 | 12.0 | 18.8 | |||||
| History of diabetes | 1.1 | 1.0 | 0.6 | 2.8 | 4.0 | |||||
| Non-Hispanic white race | 92.9 | 94.3 | 95.3 | 93.6 | 94.9 | |||||
Abbreviations: METs, metabolic equivalents; SD, standard deviation.
a Data were standardized to the age distribution of the study population.
b Values were not age-adjusted.
c Weight (kg)/height (m)2.
d Recreational and leisure-time activity.