Standard Disease Activity Parameters and Step Activity in Patients With Rheumatoid Arthritis Receiving Etanercept

• Changes from baseline in the step counts during a therapy with etanercept in patients with active rheumatoid arthritis [ Time Frame: at baseline, after 4, and after 12 weeks for ] [ Designated as safety issue: No ]
  During the therapy with etanercept steps will be counted by the Step watch monitor (SAM) for 7 days before therapy(baseline), after 4 weeks, and after 12 weeks.
  
  

• Correlation of the step counts with the health-assessment-questionnaire and the disease activity measured by DAS28 during a therapy with etanercept [ Time Frame: Baseline, week 4 and week 12 ] [ Designated as safety issue: No ]

  The results of the step watch monitor will be correlated to the results of the the health-assessment-questionnaire (HAQ) and DAS28 under the therapy with etanercept.

  We will measure the step activity by SAM at basline, week 4 and week 12 after initiation of etanercept. At the same time we will will measure the health-assessment-questionnaire (HAQ)and the disease activity score (DAS28).

  
  

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.