Data on activities of daily living in patients with rheumatoid arthritis are assessed mainly be the health assessment questionnaire (HAQ). The HAQ generates data by subjective variables. It would be desirable and advantageous to add objective tools reflecting patients' activities to the outcome parameters in rheumatoid arthritis. The StepWatch™ activity monitor (SAM) in an ankle worn step counter and an accurate instrument to measure real world ambulatory activity. The investigators purpose was to investigate whether activities of daily living measured by SAM increase during a therapy with the TNF-alpha inhibitor etanercept in patients with active rheumatoid arthritis (RA).

In the past decade treatment strategies for rheumatoid arthritis (RA) have changed dramatically. Today far more therapeutic options are available. Patients are being treated earlier and more aggressive than in the past.

These processes have had an influence on the outcome of patients with RA and on the way they are being evaluated.

Outcome variables are disease aspects or consequences that develop over the course of RA. The HAQ score has been shown to be a good predictor of patients outcome in RA. However, the HAQ ist a questionnaire and the score is influenced by subjective factors.

The Step Watch Activity monitor (SAM)is a highly accurate accelerometer-based step monitor. The SAM provides a detailed profile of the number of steps taken by a subject. It is a small unobtrusive device which is worn laterally at the right ankle. It weights only 65 grams and uses 2D accelerometry.

The SAM can provide objective information about activities of daily living.

Etanercept is a recombinant fully human TNF-receptor p75-Fc fusion protein. Numerous studies with etanercept have shown the clinical efficacy. This can be demonstrated by various disease activity scores (e.g the DAS28). In addition there is strong evidence that etanercept improves disability measured by the HAQ.

There are only few publications reporting about measuring physical activity in patients with joint diseases; all of these include patients with osteoarthritis.

Our aim is to include patients with active RA who receive etanercept. These patients are asked to wear the SAM for 7 days before treatment and 4 weeks and 12 weeks after initiation of therapy with etanercept. The step activity measured by the SAM will be correlated with the the clinical sore DAS28 and the HAQ.

Inclusion Criteria:

• Patients with active rheumatoid arthritis (Disease activity score -DAS28 > 3.2) who are eligible to a treatment with etanercept.
• Age 18 and older
• Male or female

Exclusion Criteria:

• Contraindications against a therapy with etanercept
• Patients not able to comply with the requirements of the protocol

Patients with active rheumatoid arthritis, who are eligible to a treatment with etanercept according to the local german guidelines