Multivariable associations between patient characteristics and not experiencing any blood-test abnormalitiesa among those with RA who were prescribed methotrexate, and those with IBD who were prescribed azathioprineb
| Characteristic | Odds ratio | 95% CI | P-value |
|---|---|---|---|
| RA/methotrexate cohortc | |||
| Age group, years, versus 18–39 | |||
| 40–59 | 0.79 | 0.55 to 1.13 | 0.21 |
| 60–79 | 0.56 | 0.39 to 0.79 | <0.001 |
| ≥80 | 0.26 | 0.17 to 0.40 | <0.001 |
| Sex, versus male | |||
| Female | 1.11 | 0.94 to 1.30 | 0.22 |
| Socioeconomic status, IMD quintile, versus 5 (least deprived) | |||
| 4 | 0.95 | 0.77 to 1.17 | 0.61 |
| 3 | 0.96 | 0.77 to 1.20 | 0.70 |
| 2 | 0.95 | 0.75 to 1.21 | 0.69 |
| 1 (most deprived) | 0.90 | 0.70 to 1.16 | 0.40 |
| Long-term conditions | |||
| CKD versus no CKD | 0.37 | 0.21 to 0.67 | <0.001 |
| CVD versus no CVD | 0.51 | 0.30 to 0.85 | 0.01 |
| Diabetes type 1 or 2 versus no diabetes | 0.66 | 0.51 to 0.83 | <0.001 |
| Hypertension versus no hypertension | 0.93 | 0.79 to 1.10 | 0.41 |
| IBD/azathioprine cohortd | |||
| Age group, years, versus 18–39 | |||
| 40–59 | 1.35 | 1.03 to 1.79 | 0.03 |
| 60–79 | 0.65 | 0.45 to 0.93 | 0.02 |
| ≥80 | 0.09 | 0.01 to 0.33 | 0.002 |
| Sex, versus male | |||
| Female | 0.96 | 0.75 to 1.22 | 0.72 |
| Socioeconomic status, IMD quintile, versus 5 (least deprived) | |||
| 4 | 1.41 | 0.99 to 2.01 | 0.06 |
| 3 | 0.90 | 0.63 to 1.28 | 0.55 |
| 2 | 0.83 | 0.57 to 1.22 | 0.34 |
| 1 (most deprived) | 0.85 | 0.57 to 1.26 | 0.41 |
| Long-term conditions | |||
| CKD versus no CKD | 0.39 | 0.17 to 0.82 | 0.02 |
| Diabetes type 1 or 2 versus no diabetes | 0.57 | 0.35 to 0.94 | 0.03 |
| Hypertension versus no hypertension | 0.91 | 0.61 to 1.36 | 0.64 |
↵a Using NICE-specified thresholds and tests (test thresholds: WBC ≥3.5×109/L; MCV ≤105 fL; neutrophils ≥1.6×109/L; platelets ≥140×109/L; eosinophils ≤0.5×109/L; ALT ≤100 U/L; AST ≤100 U/L; albumin ≥30 g/L; and eGFR ≥60 ml/min/1.73 m2).
↵b Models adjusted for age, sex, socioeconomic status, and long-term conditions. Small numbers with CVD and heart failure in the IBD azathioprine group meant this condition combination was not included in the multivariable model as it was for the RA/methotrexate group.
↵c Patients with prevalent and incident RA prescribed methotrexate in any 2-month period over the study period.
↵d Patients with prevalent and incident IBD prescribed azathioprine in any 2-month period over the study period. ALT = alanine aminotransferase. AST = aspartate transaminase. CKD = chronic kidney disease (excluding dialysis and transplant). CVD = cardiovascular disease (including ischaemic heart disease, cerebrovascular disease, heart failure, and peripheral vascular disease). eGFR = estimated glomerular filtration rate. IBD = inflammatory bowel disease. IMD = Index of Multiple Deprivation. MCV = mean cell volume. NSAID = non-steroidal anti-inflammatory drug. RA = rheumatoid arthritis. WBC = white blood cell.