RA patients currently smoking

RA patients who previously smoked

Non smoking RA patients

Difference in disease activity score (DAS 28) in smoking vs non-smoking RA-patients

Disease activity, DAS28, is calculated using a specific formula based on:

number of painful joints out of 28 joints examined number of swollen joints out of 28 joints examined erythrocyte sedimentation rate (ESR) or C reactive protein (CRP) patient's global assessment of disease activity on a 100 mm visual analogue scale (VAS)

DAS thresholds:

DAS28 lower than 2.6: remission DAS28 below 3.2: low disease activity DAS28 over 3.2 and under 5.1: moderate disease activity DAS28 above 5.1: high disease activity

Difference in pain sensitivity in smoking vs non-smoking RA-patients. Testing of of all patients' pressure pain detection threshold (PPDT), i-e pain sensitivity is performed by trained personnel, using an algometer. The algometer is placed bilaterally on the nail of the thumb and on the second metatarsophalangeal joint (MTP2), giving a total of four measured points. A progressively increasing pressure is applied with the algometer and the patients are carefully instructed to signal as soon as the pressure sensation turns into pain (not to withstand the pain) and the algometer is removed. The amount of applied force shown in kPa in the display is reported as the PPDT. The measurements are performed twice for each point and an average value is calculated as the patients' pain sensitivity threshold/pressure pain detection threshold.

Difference in pain perception in smoking vs non-smoking RA-patients

Subjective pain perception is registered by self-reported estimation of pain on a visual analogue scale (VAS) of 100 mm concerning the week preceding the study.

Difference in cardiovascular risk (Framingham score) in smoking vs non-smoking RA-patients

The Framingham risk score is a gender-specific algorithm used to estimate the 10-year cardiovascular risk of an individual calculated on the basis of the following:

Age Gender Total cholesterol HDL cholesterol Smoker Diabetes Systolic blood pressure Treatment for high blood pressure