Table 1 Demographic and baseline characteristics
| Â | Â | Total (N = 9967) | Omeprazole (N = 7888) | Other drugs (N = 2079) |
|---|---|---|---|---|
Age | < 40 years | 1503 (15.1) | 1169 (14.8) | 334 (16.1) |
|  | ≥40 - <65 years | 3929 (39.4) | 3107 (39.4) | 822 (39.5) |
|  | ≥65 years | 4535 (45.5) | 3612 (45.8) | 923 (44.4) |
Sex | Men | 4178 (41.9) | 3246 (41.2) | 932 (44.8) |
| Â | Women | 5789 (58.1) | 4642 (58.9) | 1147 (55.2) |
Body mass index, kg/m2 | < 18.5 | 404 (4.1) | 301 (3.8) | 103 (5.0) |
|  | ≥18.5 - <25 | 4134 (41.5) | 3234 (41.0) | 900 (43.3) |
|  | ≥25 | 1786 (17.9) | 1378 (17.5) | 408 (19.6) |
| Â | Unknown | 3643 (36.6) | 2975 (37.7) | 668 (32.1) |
Habitual smoking | No | 7310 (73.3) | 5744 (72.8) | 1566 (75.3) |
| Â | Yes | 1685 (16.9) | 1333 (16.9) | 352 (16.9) |
| Â | Unknown/not specified | 972 (9.8) | 811 (10.3) | 161 (7.7) |
Habitual alcohol consumption | No | 5777 (58.0) | 4608 (58.4) | 1169 (56.2) |
| Â | Yes | 3180 (31.9) | 2444 (31.0) | 736 (35.4) |
| Â | Unknown/not specified | 1010 (10.1) | 836 (10.6) | 174 (8.4) |
H. pylori eradication | No | 5712 (57.3) | 4503 (57.1) | 1209 (58.2) |
| Â | Yes | 583 (5.9) | 454 (5.8) | 129 (6.2) |
| Â | Unknown | 3672 (36.8) | 2931 (37.2) | 741 (35.6) |
H. pylori infection | No | 3003 (30.1) | 2348 (29.8) | 655 (31.5) |
| Â | Yes | 513 (5.2) | 415 (5.3) | 98 (4.71) |
| Â | Unknown/not specified | 6451 (64.7) | 5125 (65.0) | 1326 (63.8) |
Past and concurrent diseases (reported in ≥5% patients) | ||||
Past disease | No | 8480 (85.1) | 6763 (85.7) | 1717 (82.6) |
| Â | Yes | 1487 (14.9) | 1125 (14.3) | 362 (17.4) |
Concurrent disease | No | 3789 (38.0) | 2940 (37.3) | 849 (40.8) |
| Â | Yes | 6178 (62.0) | 4948 (62.7) | 1230 (59.2) |
Esophageal hiatus hernia | Past disease | 26 (0.3) | 19 (0.2) | 7 (0.3) |
| Â | Concurrent disease | 844 (8.5) | 690 (8.8) | 154 (7.4) |
Gastritis (chronic/acute) | Past disease | 258 (2.6) | 190 (2.4) | 68 (3.3) |
| Â | Concurrent disease | 1536 (15.4) | 1278 (16.2) | 258 (12.4) |
Diabetes mellitus | Past disease | 45 (0.5) | 32 (0.4) | 13 (0.6) |
| Â | Concurrent disease | 586 (5.9) | 463 (5.9) | 123 (5.9) |
Hyperlipidaemia | Past disease | 129 (1.3) | 98 (1.2) | 31 (1.5) |
| Â | Concurrent disease | 1831 (18.4) | 1477 (18.7) | 354 (17.0) |
Hypertension | Past disease | 151 (1.5) | 120 (1.5) | 31 (1.5) |
| Â | Concurrent disease | 2860 (28.7) | 2290 (29.0) | 570 (27.4) |
Insomnia | Past disease | 48 (0.5) | 36 (0.5) | 12 (0.6) |
| Â | Concurrent disease | 756 (7.6) | 592 (7.5) | 164 (7.9) |
Duration of RE | ||||
| Â | < 3 months | 6236 (62.6) | 5041 (63.9) | 1195 (57.5) |
|  | ≥3 - <6 months | 963 (9.7) | 776 (9.8) | 187 (9.0) |
|  | ≥6 months | 2767 (27.8) | 2070 (26.2) | 697 (33.5) |
| Â | Not specified | 1 (0) | 1 (0) | 0 (0) |
Prior treatment for RE | ||||
Treatment for RE during the 4 weeks prior to the investigation | No | 7769 (78.0) | 6218 (78.8) | 1551 (74.6) |
| Â | Yes | 2007 (20.1) | 1532 (19.4) | 475 (22.9) |
|  |    H2 blockers | 1519 (15.2) | 1161 (14.7) | 358 (17.2) |
|  |    Prokinetics | 509 (5.1) | 391 (5.0) | 118 (5.7) |
|  |    Antacids | 197 (2.0) | 151 (1.9) | 46 (2.2) |
|  |    Mucosal protectants | 536 (5.4) | 410 (5.2) | 126 (6.1) |
|  |    Antianxiety drugs | 101 (1.0) | 69 (0.9) | 32 (1.5) |
|  |    Antidepressants | 47 (0.5) | 32 (0.4) | 15 (0.7) |
|  |    Chinese herbal medicines | 59 (0.6) | 37 (0.5) | 22 (1.1) |
|  |    Other drugs | 95 (1.0) | 71 (0.9) | 24 (1.2) |
| Â | Unknown | 191 (1.9) | 138 (1.8) | 53 (2.6) |
PPI use during the past 5 years | Â | Â | Â | Â |
| Â | No | 6953 (69.8) | 5462 (69.2) | 1491 (71.7) |
| Â | Yes | 1761 (17.7) | 1444 (18.3) | 317 (15.3) |
|  |    < 6 months | 809 (8.1) | 663 (8.4) | 146 (7.0) |
|  |    ≥6 months - <1 year | 408 (4.1) | 337 (4.3) | 71 (3.4) |
|  |    ≥1 - <2 years | 323 (3.2) | 259 (3.3) | 64 (3.1) |
|  |    ≥2 - <5 years | 213 (2.1) | 178 (2.3) | 35 (1.7) |
|  |    ≥5 years | 8 (0.1) | 7 (0.1) | 1 (0.1) |
| Â | Unknown | 1253 (12.6) | 982 (12.5) | 271 (13.0) |