Table 1.
Characteristics of study groups
| Cases | GERD controls | Population controls | |
|---|---|---|---|
| Number or Mean (% or standard deviation) | Number or Mean (% or standard deviation) | Number or Mean (% or standard deviation) | |
| Number of subjects | 320 | 316 | 317 |
| Age (years) | |||
| 20-39 | 9 (3) | 12 (4) | 9 (3) |
| 40-59 | 120 (38) | 116 (37) | 105 (33) |
| 60-79 | 191 (59) | 188 (59) | 203 (64) |
| Race | |||
| White | 261 (82) | 249 (79) | 264 (83) |
| Hispanic | 25 (8) | 20 (6) | 13 (4) |
| Black | 5 (2) | 21 (7) | 17 (5) |
| Asian | 19 (6) | 11 (3) | 12 (4) |
| Others/Mixed/Unknown | 10 (3) | 15 (5) | 11 (4) |
| Gender | |||
| Male | 234 (73) | 218 (69) | 214 (68) |
| Smoking status | |||
| Non smoker | 108 (34) | 129 (41) | 140 (44) |
| Current smoker | 51 (16) | 40 (13) | 39 (12) |
| Ever smoker | 212 (66) | 187 (59) | 176 (56) |
| Alcohol use status | |||
| Non drinker | 99 (31) | 114 (36) | 85 (27) |
| Light drinker (<7/wk) | 155 (48) | 133 (42) | 158 (50) |
| Moderate drinker (7-13/wk) | 27 (8) | 27 (9) | 48 (15) |
| Heavy drinker (14+/wk) | 39 (12) | 42 (13) | 26 (8) |
| Body mass index (kg/m2) | 29.5 (±0.3) | 28.9 (±0.3) | 29.5 (±0.3) |
Eligible Barrett's esophagus cases were frequency matched to control groups by gender, age (by 5 year age groups) and center of diagnosis.