Table 1.
Baseline characteristics of participants by use of proton pump inhibitors.
| Characteristica | Nurses’ Health Study (2000) Nurses’ Health Study II (2001) |
Health Professionals Follow-Up Study (2004) | ||
|---|---|---|---|---|
| Non-users (n = 141,809) | Users (n = 9368) | Non-users (n = 20,845) | Users (n = 3837) | |
| Age (years)b | 56 (11) | 57 (11) | 69 (9) | 70 (9) |
| Body mass index (kg/m2) | 25 (5) | 27 (6) | 26 (3) | 26 (3) |
| Activity (MET-h/week) | 19 (19) | 16 (16) | 35 (28) | 32 (26) |
| Total folate intake (µg/day) | 462 (212) | 458 (205) | 609 (231) | 623 (233) |
| Total vitamin D (IU/day) | 372 (201) | 377 (198) | 446 (228) | 461 (234) |
| Total calcium intake (mg/day) | 1058 (388) | 1081 (403) | 969 (339) | 992 (355) |
| Total fat (g/day) | 60 (10) | 60 (10) | 68 (12) | 69 (12) |
| Total fibre (g/day) | 19 (5) | 18 (5) | 23 (6) | 22 (6) |
| Alcohol (g/day) | 5 (7) | 4 (7) | 11 (13) | 11 (13) |
| Total energy intake (kcal/day) | 1767 (465) | 1778 (473) | 2000 (531) | 1989 (534) |
| Red meat (servings/week) | 4 (2) | 4 (2) | 4 (3) | 4 (3) |
| Processed meat (servings/week) | 2 (2) | 2 (2) | 2 (2) | 2 (2) |
| History of sigmoidoscopy/colonoscopy | 39 | 55 | 73 | 84 |
| Family history of colorectal cancer | 13 | 14 | 13 | 14 |
| H2RA use | 6 | 11 | 5 | 14 |
| Regular aspirin use (≥2 tablets/week) | 27 | 35 | 49 | 53 |
| Regular NSAID use (≥2 tablets/week) | 33 | 44 | 29 | 39 |
| Multivitamin use | 62 | 63 | 68 | 71 |
| White | 97 | 98 | 96 | 97 |
| Menopausal hormone therapy use | 40 | 48 | N/A | N/A |
| Postmenopausal status | 55 | 59 | N/A | N/A |
| History of smoking | ||||
| Never | 56 | 52 | 53 | 49 |
| Past | 35 | 39 | 44 | 48 |
| Current | 9 | 9 | 4 | 3 |
H2RA H2 receptor antagonist, MET metabolic equivalent, NSAID nonsteroidal anti-inflammatory drugs.
aAge-adjusted means (standard deviation) for continuous variables, and percentages for categorical variables.
bValues not age adjusted.