Table 1.
Characteristics of patients with and without ankylosing spondylitis (AS) who were hospitalised for pneumonia from 1997 to 2016 in Denmark
| AS N (%) |
Non-AS N (%) |
|
| N | 842 (0.2) | 386.954 (99.8) |
| Age, median (IQR) | 65 (52–74) | 71 (57–81) |
| 16–29 years | 22 (2.6) | 15.965 (4.1) |
| 30–44 years | 102 (12.1) | 35.690 (9.2) |
| 45–59 years | 195 (23.2) | 58.375 (15.1) |
| 60–74 years | 316 (37.5) | 111.667 (28.9) |
| 75 years and above | 207 (24.6) | 165.247 (42.7) |
| Sex | ||
| Female | 218 (25.9) | 190.532 (49.2) |
| Male | 624 (74.1) | 196.422 (50.8) |
| Pneumonia 1997–2006 | 274 (0.2) | 161.597 (99.8) |
| Pneumonia 2006–2017 | 568 (0.3) | 224.500 (99.7) |
| Comorbidity within 10 years before pneumonia | ||
| Congestive heart failure | 97 (11.5) | 30.946 (8.0) |
| Peripheral vascular disease | 66 (7.8) | 26.598 (6.9) |
| Previous myocardial infarction | 48 (5.7) | 20.386 (5.3) |
| Chronic pulmonary disease | 152 (18.1) | 60.981 (15.8) |
| Cerebrovascular disease | 91 (10.8) | 48.986 (12.7) |
| Hemiplegia | 19 (2.7) | 1.917 (0.5) |
| Dementia | 7 (0.8) | 13.304 (3.4) |
| Connective tissue disease | 79 (9.4) | 9.834 (2.5) |
| Peptic ulcer disease | 54 (6.4) | 17.479 (4.5) |
| Diabetes type I and II | 77 (9.1) | 30.399 (7.8) |
| Diabetes with end organ damage | 46 (5.5) | 17.004 (4.4) |
| Moderate to severe renal disease | 45 (5.3) | 13.961 (3.6) |
| Any tumour | 98 (11.6) | 52.629 (13.6) |
| Leukaemia | 5 (0.6) | 3.484 (0.9) |
| Lymphoma | 13 (1.5) | 6.205 (1.6) |
| Metastatic solid tumour | 18 (2.1) | 9.365 (2.4) |
| Mild liver disease | 16 (1.9) | 5.636 (1.5) |
| Moderate-to-severe liver disease | 2 (0.2) | 1.72 (0.45) |
| AIDS | 0 | 545 (0.1) |
| Comorbidity index (level of Charlson Index Score) | ||
| Low (0) | 350 (41.6) | 180.629 (46.8) |
| Medium (1–2) | 316 (37.5) | 137.850 (35.7) |
| High (≥3) | 176 (20.1) | 67.934 (17.6) |
| Duration of hospital stay in days, median (IQR) | 6 (3–11.5) | 7 (4–12) |