From: Antibiotic use and the risk of rheumatoid arthritis: a population-based case-control study
Variables | Controls | Cases | Crude OR (95% CI) | Adjusted ORa (95% CI) | ||
---|---|---|---|---|---|---|
N | % | N | % | |||
Any antibiotic use | ||||||
 No prescriptions | 16,242 | 18.0 | 2369 | 10.4 | Reference | Reference |
 ≥ 1 prescription | 73,771 | 82.0 | 20,308 | 89.6 | 2.02 (1.92–2.12) | 1.60 (1.51–1.68) |
No. of prescriptions (quartile) (median (IQR)) | ||||||
 1 (1 (1, 2)) | 20,321 | 22.6 | 4128 | 18.2 | 1.49 (1.41–1.57) | 1.40 (1.32–1.48) |
 2 (4 (3, 5)) | 18,923 | 21.0 | 4592 | 20.2 | 1.85 (1.75–1.96) | 1.66 (1.57–1.77) |
 3 (8 (7, 9)) | 17,524 | 19.5 | 5231 | 23.1 | 2.36 (2.23–2.50) | 2.04 (1.92–2.17) |
 4 (19 (14, 29)) | 17,003 | 18.9 | 6357 | 28.0 | 3.10 (2.93–3.28) | 2.56 (2.39–2.74) |
Recency of therapy (therapy termination)b | ||||||
 1–2 years before diagnosis | 30,041 | 35.2 | 9557 | 43.9 | 2.34 (2.23–2.46) | 1.80 (1.70–1.90) |
 2–5 years before diagnosis | 26,898 | 31.5 | 7016 | 32.2 | 1.91 (1.81–2.01) | 1.57 (1.49–1.66) |
 5–10 years before diagnosis | 12,183 | 14.3 | 2846 | 13.1 | 1.70 (1.59–1.80) | 1.48 (1.39–1.58) |
Antibiotic type | ||||||
 Bacteriostatic | ||||||
  Unexposedc | 43,580 | 48.4 | 8778 | 38.7 | Reference | Reference |
  Exposed | 46,433 | 51.6 | 13,899 | 61.3 | 1.55 (1.50–1.60) | 1.31 (1.27–1.36) |
 Bactericidal | ||||||
  Unexposedd | 21,892 | 24.3 | 3595 | 15.9 | Reference | Reference |
  Exposed | 68,121 | 75.7 | 19,082 | 84.2 | 1.80 (1.72–1.87) | 1.45 (1.39–1.51) |