TABLE 1.
Odds ratios (95% CIs) for the association between patient characteristics and the risk of gastric cancer
| Cases (n = 727) | Controls (n = 5000) | |||||
|---|---|---|---|---|---|---|
| n | % | n | % | OR (95% CI) a | OR (95% CI) b | |
| Sex | ||||||
| Male | 494 | 68.0 | 3387 | 67.7 | — | — |
| Female | 233 | 32.0 | 1613 | 32.3 | — | — |
| Age at index date (years) | ||||||
| 40‐49 | 14 | 1.9 | 93 | 1.9 | — | — |
| 50‐59 | 44 | 6.1 | 305 | 6.1 | — | — |
| 60‐69 | 154 | 21.2 | 1066 | 21.3 | — | — |
| 70‐79 | 303 | 41.7 | 2072 | 41.4 | — | — |
| ≥80 | 212 | 29.2 | 1464 | 29.3 | — | — |
| GP visits | ||||||
| 0‐4 | 21 | 2.9 | 574 | 11.5 | 1.0 (reference) | 1.0 (reference) |
| 5‐9 | 87 | 12.0 | 1235 | 24.7 | 1.98 (1.22‐3.23) | 1.98 (1.21‐3.23) |
| 10‐19 | 292 | 40.2 | 1931 | 38.6 | 4.30 (2.73‐6.78) | 4.21 (2.67‐6.64) |
| ≥20 | 327 | 45.0 | 1260 | 25.2 | 7.52 (4.76‐11.86) | 7.33 (4.64‐11.57) |
| BMI (kg/m2) | ||||||
| 15‐19 (underweight) | 30 | 4.1 | 162 | 3.2 | 1.26 (0.83‐1.92) | 0.99 (0.65‐1.53) |
| 20‐24 (healthy weight) | 201 | 27.6 | 1353 | 27.1 | 1.0 (reference) | 1.0 (reference) |
| 25‐29 (overweight) | 274 | 37.7 | 1944 | 38.9 | 0.95 (0.78‐1.15) | 0.93 (0.76‐1.14) |
| ≥30 (obese) | 166 | 22.8 | 1183 | 23.7 | 0.94 (0.75‐1.18) | 0.82 (0.65‐1.03) |
| Missing | 56 | 7.7 | 358 | 7.2 | 1.05 (0.76‐1.45) | 1.32 (0.95‐1.84) |
| Smoking | ||||||
| Nonsmoker | 221 | 30.4 | 1955 | 39.1 | 1.0 (reference) | 1.0 (reference) |
| Current | 129 | 17.7 | 614 | 12.3 | 1.89 (1.49‐2.39) | 1.78 (1.40‐2.28) |
| Former | 376 | 51.7 | 2408 | 48.2 | 1.39 (1.16‐1.67) | 1.24 (1.03‐1.49) |
| Missing | 1 | 0.1 | 23 | 0.5 | 0.38 (0.05‐2.86) | 0.48 (0.06‐3.64) |
| Alcohol consumption (units/week) | ||||||
| None | 133 | 18.3 | 940 | 18.8 | 1.0 (reference) | 1.0 (reference) |
| 1‐9 | 347 | 47.7 | 2245 | 44.9 | 1.08 (0.87‐1.34) | 1.11 (0.89‐1.39) |
| 10‐20 | 101 | 13.9 | 838 | 16.8 | 0.84 (0.63‐1.11) | 0.87 (0.65‐1.17) |
| 21‐41 | 29 | 4.0 | 284 | 5.7 | 0.70 (0.46‐1.08) | 0.72 (0.46‐1.11) |
| ≥42 | 18 | 2.5 | 112 | 2.2 | 1.11 (0.65‐1.90) | 0.99 (0.57‐1.71) |
| Missing | 99 | 13.6 | 581 | 11.6 | 1.19 (0.90‐1.58) | 1.38 (1.03‐1.84) |
| Frailty | ||||||
| Fit | 249 | 34.3 | 2235 | 44.7 | 1.0 (reference) | 1.0 (reference) |
| Mild frailty | 293 | 40.3 | 1807 | 36.1 | 1.56 (1.30‐1.89) | 0.98 (0.80‐1.20) |
| Moderate frailty | 146 | 20.1 | 733 | 14.7 | 2.02 (1.59‐2.56) | 0.99 (0.76‐1.29) |
| Severe frailty | 39 | 5.4 | 225 | 4.5 | 1.82 (1.24‐2.67) | 0.76 (0.50‐1.14) |
| Comorbidity | ||||||
| Hypertension | 670 | 54.6 | 2553 | 56.7 | 0.83 (0.71‐0.98) | 0.69 (0.59‐0.82) |
| Hyperlipidemia | 165 | 22.7 | 1210 | 24.2 | 0.92 (0.76‐1.11) | 0.87 (0.72‐1.06) |
| Ischaemic stroke | 37 | 5.1 | 318 | 6.4 | 0.79 (0.55‐1.12) | 0.66 (0.46‐0.94) |
| IHD | 131 | 18.0 | 916 | 18.3 | 0.98 (0.80‐1.20) | 0.81 (0.66‐1.00) |
| Diabetes | 127 | 17.5 | 871 | 17.4 | 1.00 (0.82‐1.23) | 0.74 (0.60‐0.91) |
| Anaemia | 95 | 13.1 | 126 | 2.5 | 5.95 (4.49‐7.89) | 4.73 (3.54‐6.31) |
| Pernicious anaemia | 16 | 1.1 | 23 | 0.5 | 4.19 (2.04‐8.62) | 3.21 (1.54‐6.68) |
| Dyspepsia | 274 | 37.7 | 1071 | 21.4 | 2.23 (1.89‐2.63) | 1.89 (1.60‐2.24) |
| GORD | 176 | 24.2 | 824 | 16.5 | 1.63 (1.35‐1.96) | 1.35 (1.12‐1.64) |
| Hiatus hernia | 50 | 6.9 | 338 | 6.8 | 1.02 (0.75‐1.39) | 0.85 (0.62‐1.16) |
| Peptic ulcer c /UGIB/unspecified GIB | 173 | 23.8 | 377 | 7.5 | 3.90 (3.18‐4.77) | 3.25 (2.64‐4.00) |
| LGIB | 55 | 7.6 | 387 | 7.7 | 0.98 (0.73‐1.31) | 0.86 (0.64‐1.16) |
| Complicated peptic ulcer | 67 | 9.2 | 145 | 2.9 | 3.44 (2.54‐4.66) | 2.95 (2.16‐4.02) |
| Uncomplicated peptic ulcer | 129 | 17.7 | 272 | 5.4 | 3.79 (3.02‐4.76) | 3.19 (2.52‐4.03) |
| IBD | 6 | 0.8 | 89 | 1.8 | 0.46 (0.20‐1.05) | 0.37 (0.16‐0.86) |
| IBS | 32 | 4.4 | 243 | 4.9 | 0.90 (0.62‐1.32) | 0.74 (0.50‐1.09) |
| Proxy measure for H. pylori infection | 56 | 7.7 | 130 | 2.6 | 3.14 (2.27‐4.34) | 2.74 (1.96‐3.83) |
| Medications | ||||||
| Clopidogrel | 52 | 7.2 | 253 | 5.1 | 1.46 (1.07‐1.99) | 1.15 (0.84‐1.58) |
| Oral anticoagulant | 62 | 8.5 | 336 | 6.7 | 1.32 (0.99‐1.75) | 0.88 (0.66‐1.18) |
| PPI | 449 | 61.8 | 1261 | 25.2 | 5.92 (4.96‐7.08) | 4.80 (3.99‐5.77) |
| H2RA | 48 | 6.6 | 118 | 2.4 | 3.01 (2.13‐4.25) | 2.69 (1.88‐3.84) |
| Antacid | 105 | 14.4 | 261 | 5.2 | 3.11 (2.44‐3.97) | 2.58 (2.01‐3.30) |
| NSAID | 31 | 4.3 | 355 | 7.1 | 0.59 (0.40‐0.85) | 0.50 (0.34‐0.74) |
| Treatment for H. pylori | 29 | 4.0 | 87 | 1.7 | 2.35 (1.53‐3.60) | 2.08 (1.34‐3.24) |
Note: Comorbidities were identified any time before the index date except for anaemia, where we included recorded diagnoses in the year before the index date, and pernicious anaemia, where we included recorded diagnoses in the 5 years before the index date.
Abbreviations: BMI, body mass index; CI, confidence interval; COXIB, cyclooxygenase‐2 inhibitors, DVT, deep vein thrombosis; GIB, gastrointestinal bleeding; GORD, gastro‐oesophageal reflux disease; GP, general practitioner; H2RA, histamine2 receptor antagonist; IBD, irritable bowel disease; IBS, inflammatory bowel syndrome; IHD, ischaemic heart disease; LGIB, lower gastrointestinal disease; NSAID, nonsteroidal anti‐inflammatory drug; OR, odds ratio; PPI, proton pump inhibitor; TIA, transient ischaemic attack; tNSAID, traditional nonsteroidal anti‐inflammatory drug; UGIB, upper gastrointestinal bleeding.
Adjusted by the matching factors: sex, age and calendar year.
Adjusted by the matching factors: sex, age, and calendar year, and by smoking, number of GP visits in the year before the index date and current use of low‐dose aspirin.
Includes both complicated and uncomplicated peptic ulcer.