Table 2.
Summary of clinical predictors of response to MTX and other DMARDs.
| Factors | Predictor of response? | Comments |
|---|---|---|
| Gender | Yes, men respond better to MTX | Both in early and established RA; not extendable to other DMARDs |
| Age | No | Strong evidence showing lack of influence on MTX responsiveness, a few contradicting studies; probably also no influence on other DMARDs |
| Ethnicity | Uncertain | Despite the theoretical rationale, more data is needed |
| Smoking | Likely, active smokers respond worse to MTX | Most studies do not analyze it; however, available studies point to worse response in active smokers; not certain as to extension to other DMARDs |
| Disease duration | Yes, better response in early RA | Early RA has better response than established RA, but no influence of duration in longstanding disease; controversial results due to methodological heterogeneity |
| Prior DMARD use | Yes, worse response | Previous DMARD use associated with worse response to MTX and other DMARDs; however, not confirmed in some studies; results likely to be affected by several clinical confounders |
| Disease activity measured by composite scores | Yes, worse response if higher baseline activity | However, frequently not replicable with different scores; unclear which scores are better, likely to depend on response measures used |
| Disease activity measured by isolated variables | Uncertain | Contradicting findings; unreliable when variables are used separately |
| Disability | Uncertain, not likely | No association in most studies; inverse relation between HAQ and response in some early RA studies |
| Pain global assessment | No | Strong evidence showing lack of influence on response to MTX and other DMARDs; a few contradicting studies |
| Concomitant NSAIDs | Uncertain | Only two studies suggesting higher response to MTX in NSAIDs users; more data needed |
| Concomitant corticosteroids | Likely, better response | Although most studies fail to analyze it, combined therapy with steroids seems to have better results than DMARD monotherapy |
| Radiographic scores | No | Extensively shown that baseline radiographic scores do not predict clinical response to any DMARD |
Conclusions and comments are based on the findings reported and discussed in the text. DMARDs, disease modifying anti-rheumatic drugs; HAQ, health assessment questionnaire; MTX, methotrexate; NSAIDs, non-steroidal anti-inflammatory drugs; RA, rheumatoid arthritis.