Baseline characteristics of study population at index date, stratified by oral GC and PPI therapy status during follow-up (N=12 351)
| Concomitant users of oral GCs and PPIs* (N=4254) | Users of oral GCs alone† (N=2136) | Users of PPIs alone‡ (N=2823) | Non-users (N=3138) | |||||
| N | % | N | % | N | % | N | % | |
| Mean duration of follow-up (years, SD) | 9.1 | 5.0 | 7.5 | 4.9 | 8.4 | 5.0 | 5.1 | 4.3 |
| Age (years)§ | ||||||||
| Mean, SD | 67.5 | 8.4 | 68.3 | 8.8 | 67.5 | 8.5 | 69.0 | 9.2 |
| 50–59 | 802 | 18.9 | 390 | 18.3 | 540 | 19.1 | 550 | 17.5 |
| 60–69 | 1763 | 41.4 | 813 | 38.1 | 1190 | 42.2 | 1102 | 35.1 |
| 70–79 | 1328 | 31.2 | 699 | 32.7 | 842 | 29.8 | 1055 | 33.6 |
| 80+ | 361 | 8.5 | 234 | 11.0 | 251 | 8.9 | 431 | 13.7 |
| Number of women | 2837 | 66.7 | 1443 | 67.6 | 2003 | 71.0 | 2190 | 69.8 |
| BMI (kg/m2)§ | ||||||||
| Mean, SD | 26.4 | 5.1 | 26.2 | 5.0 | 26.2 | 5.1 | 25.9 | 5.1 |
| <20.0 | 304 | 7.1 | 146 | 6.8 | 200 | 7.1 | 222 | 7.1 |
| 20.0–24.9 | 1384 | 32.5 | 735 | 34.4 | 937 | 33.2 | 1079 | 34.4 |
| 25.0–29.9 | 1482 | 34.8 | 698 | 32.7 | 981 | 34.8 | 965 | 30.8 |
| 30.0–34.9 | 586 | 13.8 | 279 | 13.1 | 377 | 13.4 | 328 | 10.5 |
| ≥35.0 | 234 | 5.5 | 109 | 5.1 | 142 | 5.0 | 151 | 4.8 |
| Missing | 264 | 6.2 | 169 | 7.9 | 186 | 6.6 | 393 | 12.5 |
| Smoking status§ | ||||||||
| Non | 1560 | 36.7 | 805 | 37.7 | 1158 | 41.0 | 1252 | 39.9 |
| Current | 988 | 23.2 | 522 | 24.4 | 571 | 20.2 | 646 | 20.6 |
| Past | 1670 | 39.3 | 770 | 36.0 | 1058 | 37.5 | 1104 | 35.2 |
| Missing | 36 | 0.8 | 39 | 1.8 | 36 | 1.3 | 136 | 4.3 |
| Alcohol use§ | ||||||||
| No | 1249 | 29.4 | 559 | 26.2 | 780 | 27.6 | 795 | 25.3 |
| Yes | 2720 | 63.9 | 1380 | 64.6 | 1819 | 64.4 | 1969 | 62.7 |
| Missing | 285 | 6.7 | 197 | 9.2 | 224 | 7.9 | 374 | 11.9 |
| History of comorbidities | ||||||||
| Asthma | 573 | 13.5 | 277 | 13.0 | 170 | 6.0 | 207 | 6.6 |
| COPD | 321 | 7.5 | 161 | 7.5 | 65 | 2.3 | 102 | 3.3 |
| Ischaemic heart disease (including myocardial infarction) | 503 | 11.8 | 234 | 11.0 | 278 | 9.8 | 323 | 10.3 |
| Cerebrovascular disease | 234 | 5.5 | 109 | 5.1 | 139 | 4.9 | 152 | 4.8 |
| Congestive heart failure | 98 | 2.3 | 70 | 3.3 | 61 | 2.2 | 115 | 3.7 |
| Anaemia | 520 | 12.2 | 262 | 12.3 | 338 | 12.0 | 399 | 12.7 |
| Peripheral arterial disease | 200 | 4.7 | 103 | 4.8 | 132 | 4.7 | 139 | 4.4 |
| Gastro-oesophageal reflux disease | 198 | 4.7 | 94 | 4.4 | 130 | 4.6 | 110 | 3.5 |
| Peptic ulcer disease | 38 | 0.9 | 15 | 0.7 | 21 | 0.7 | 15 | 0.5 |
| Coeliac disease | 10 | 0.2 | 5 | 0.2 | 9 | 0.3 | 6 | 0.2 |
| Inflammatory bowel disease (Crohn’s disease and ulcerative colitis) | 45 | 1.1 | 19 | 0.9 | 28 | 1.0 | 19 | 0.6 |
| Hyperthyroidism | 24 | 0.6 | 13 | 0.6 | 16 | 0.6 | 15 | 0.5 |
| Hypothyroidism | 289 | 6.8 | 149 | 7.0 | 206 | 7.3 | 213 | 6.8 |
| Type 1 diabetes mellitus | 25 | 0.6 | 17 | 0.8 | 17 | 0.6 | 15 | 0.5 |
| Type 2 diabetes mellitus | 230 | 5.4 | 101 | 4.7 | 164 | 5.8 | 172 | 5.5 |
| Chronic renal failure | 144 | 3.4 | 68 | 3.2 | 81 | 2.9 | 110 | 3.5 |
| Ankylosing spondylitis | 6 | 0.1 | <5 | <0.3 | 5 | 0.2 | 7 | 0.2 |
| Dementia | 17 | 0.4 | 11 | 0.5 | 19 | 0.7 | 28 | 0.9 |
| Parkinson’s disease | 10 | 0.2 | 4 | 0.2 | 9 | 0.3 | 20 | 0.6 |
| Malignant neoplasms (excluding non-melanoma skin cancers) | 371 | 8.7 | 173 | 8.1 | 248 | 8.8 | 244 | 7.8 |
| Major infections¶ | 812 | 19.1 | 397 | 18.6 | 468 | 16.6 | 452 | 14.4 |
| Falls (in the past 7–12 months) | 38 | 0.9 | 10 | 0.5 | 16 | 0.6 | 21 | 0.7 |
| Comedication use (in the past 6 months) | ||||||||
| Antihypertensives | 1383 | 32.5 | 718 | 33.6 | 905 | 32.1 | 1117 | 35.6 |
| Anticoagulants | 118 | 2.8 | 70 | 3.3 | 45 | 1.6 | 104 | 3.3 |
| Calcium/vitamin D | 290 | 6.8 | 105 | 4.9 | 133 | 4.7 | 190 | 6.1 |
| Bisphosphonates | 260 | 6.1 | 87 | 4.1 | 108 | 3.8 | 119 | 3.8 |
| Hormone replacement therapy | 184 | 4.3 | 65 | 3.0 | 107 | 3.8 | 81 | 2.6 |
| Anticonvulsants | 51 | 1.2 | 29 | 1.4 | 37 | 1.3 | 46 | 1.5 |
| Hypnotics/anxiolytics | 356 | 8.4 | 168 | 7.9 | 184 | 6.5 | 189 | 6.0 |
| Antidepressants | 498 | 11.7 | 237 | 11.1 | 275 | 9.7 | 290 | 9.2 |
| Antipsychotics | 36 | 0.8 | 19 | 0.9 | 17 | 0.6 | 40 | 1.3 |
| Disease severity indicators | ||||||||
| Non-selective NSAIDs | 2309 | 54.3 | 1202 | 56.3 | 1514 | 53.6 | 1518 | 48.4 |
| COX-2 selective inhibitors | 409 | 9.6 | 205 | 9.6 | 255 | 9.0 | 191 | 6.1 |
| Paracetamol | 2117 | 49.8 | 987 | 46.2 | 1147 | 40.6 | 1328 | 42.3 |
| Tramadol | 263 | 6.2 | 113 | 5.3 | 148 | 5.2 | 138 | 4.4 |
| Opioids (stronger than tramadol) | 241 | 5.7 | 105 | 4.9 | 114 | 4.0 | 118 | 3.8 |
| csDMARDs | 1323 | 31.1 | 637 | 29.8 | 915 | 32.4 | 1091 | 34.8 |
*Concomitant users of oral GCs and PPIs are patients who had at least one co-prescription of an oral GC and PPI during follow-up.
†Users of oral GCs alone are patients who had at least one prescription of an oral GC during follow-up without having prescribed PPI and excluding concomitant users.
‡Users of PPIs alone are patients who had at least one prescription of a PPI during follow-up without having prescribed oral GCs and excluding concomitant users and users of oral GCs alone.
§At index date.
¶Major infections included sepsis, meningitis, and upper and lower respiratory tract infections.
BMI, body mass index; COPD, chronic obstructive pulmonary disease; COX-2, cyclo-oxygenase-2; csDMARDs, conventional synthetic disease-modifying antirheumatic drugs; GCs, glucocorticoids; NSAIDs, non-steroidal anti-inflammatory drugs; PPIs, proton pump inhibitors.