According to the official guidelines, patients are considered to have achieved remission when their disease activity score (DAS28) score is 2.6 or lower. (DAS28 is an international scale for assessing the activity of joint inflammation.) Several other markers are also said to indicate when patients are free from active inflammation. They are used when decisions are made as to whether the patient’s treatment should be modified or not. All these arbitrary and unnatural parameters have nothing to do with the actual condition of the patient or the activity of the disease. Despite much criticism regarding their use and applicability in medical practice, these parameters continue to be used in the assessment of disease activity and the determination of remission. Results obtained using the DAS28 scale largely depend on the country of examination, the informal social, cultural and educational level of the patients, as well as their tolerance to pain. In general, they can only be used to determine a patient’s perception of the disease at different stages. They should not be used to determine whether the disease is still active or not.
The DAS28 score is calculated from:
1. The number of swollen joints; only 28 joints are available on the list and other joints are not taken into consideration.
2. The number of tender joints; again, only 28 joints are on the list and other joints are not taken into consideration.
3. Erythrocyte sedimentation rate – in the case of DAS28 CRP, the CRP level is used instead of ESR.
4. The patient’s assessment of the disease activity using a visual assessment scale (VAS).
Criteria one and two are somewhat dubious when it comes to the assessment method, as the results depend on the physician’s knowledge and experience, as well as on the examination day and the drugs currently taken by the patient.
Only the third criterion is fully objective, as long as the patient receives no steroid drugs. The fourth criterion is very questionable since the patient’s subjective assessment depends on numerous factors and their individual tolerance to pain. Higher scores are provided by very sensitive or neurotic patients. In the case of patients who suffer from both arthritis and osteoarthritis, it is difficult to determine what exactly is hurting and whether the pain is related to the disease being evaluated. Such an assessment is often difficult and sometimes impossible.
At the other end of the scale, results are too low in patients with lower sensitivity to pain. Thus, the calculated DAS28 score is used as the basis for discontinuing the treatment of patients with arthritis who have failed to achieve actual remission, and who therefore suffer from a quick relapse of the disease. The use of such scores frequently leads to situations where patients who have arthritis in two or three joints, good blood analysis results (low ESR and CRP levels) and mild pain symptoms are deemed to be healthy. Also, the DAS28 score may suggest that the patient has been cured when only one joint is affected and presenting, e.g. it has exudate and signs of inflammation, but there is no elevation in ESR or CRP levels. In such a case, a discontinuation of the treatment or dose reduction will result in the disease activity being increased.
Imagine such an approach being used to put out a forest fire.
After successfully fighting a fire that is spreading over a 250-acre forest, the brave firemen are rewarded with a day off, despite the fact that one small coppice is still on fire. Calculations show that its area accounts for less than 0.1% of the entire forest. Obviously, no one would act like that because the fire would spread all over again. In rheumatology, however, this is standard procedure.
Again: a standard that is in line with official guidelines established by very important bodies and research institutes, which has to be followed by all rheumatologists; a standard that is being taught to medical students. As a consequence, instead of curing patients, we are continuously dealing with cases of recurrent disease. The failure to completely suppress an immunological disease is similar to the failure to properly extinguish the forest fire.