Table 1.
Characteristics of first-time rheumatoid arthritis diagnoses recorded in the Danish National Patient Registry among participants in the Danish Diet, Cancer, and Health cohort and derived from the Central Denmark Region hospitals
| Characteristics | |
|---|---|
| Registered at least once with rheumatoid arthritis diagnosis during 1977–2016, n | 331 |
| Female, % (n) | 70 (231) |
| Mean age, years (range) | 65 (35–83) |
| Calendar periods, % (n) | |
| 1977–1987 | 6 (19) |
| 1988–2010 | 70 (232) |
| 2011–2016 | 24 (80) |
| Department type, % (n) | |
| Rheumatology | 58 (192) |
| Internal medicine | 20 (65) |
| Surgery | 16 (54) |
| Other | 6 (20) |
| Patient type, % (n) | |
| Inpatient | 40 (134) |
| Outpatient | 57 (189) |
| Other | 3 (8) |
| Diagnosis type, % (n) | |
| Main (A-diagnosis) | 78 (257) |
| Secondary (B-diagnosis) | 22 (74) |
| ICD-8 codes, % (n) | 11 (37) |
| ICD-10 codes, % (n)a | 89 (294) |
| M05, % (n) | 45 (150) |
| M06, % (n) | 44 (144) |
| ICD codes by patients’ gender | |
| Men, n | 100 |
| ICD-8 codes, % (n) | 12 (12) |
| ICD-10 M05 codes, % (n) | 49 (49) |
| ICD-10 M06 codes, % (n) | 39 (39) |
| Women, n | 231 |
| ICD-8 codes, % (n) | 11 (25) |
| ICD-10 M05 codes, % (n) | 44 (101) |
| ICD-10 M06 codes, % (n) | 45 (105) |
| ICD-10 codes by patients age at the time of rheumatoid arthritis diagnosis registration | |
| M05, n | 150 |
| <50 years, % (n) | 1 (2) |
| 50–59 years, % (n) | 22 (33) |
| 60–69 years, % (n) | 44 (65) |
| >70 years, % (n) | 33 (50) |
| M06, n | 144 |
| <50 years, % (n) | 1 (2) |
| 50–59 years, % (n) | 13 (19) |
| 60–69 years, % (n) | 46 (66) |
| >70 years, % (n) | 40 (57) |
Note:
a
ICD-10 code M05 – seropositive rheumatoid arthritis, ICD-10 code M06 – other rheumatoid arthritis.
Abbreviation: ICD, International Classification of Diseases.