Page 171 - THE EVOLUTION OF EARLY ARTHRITIS AND CARDIOVASCULAR RISK Samina A. Turk

Rheumatoid arthritis (RA) is a systemic autoimmune disease, which is characterized by inflammation. This thesis is devoted to the early phase of RA and focused on three areas: (rheumatoid) arthritis development, cardiovascular comorbidity and remission from the perspective of the patient.
PART I: REVIEWING THE AT-RISK PHASE OF RHEUMATOID ARTHRITIS
The adverse consequences on physical functioning make RA a personal and socioeco- nomic burden. To avoid this burden, the onset of RA should ideally be prevented, and in this context the following questions are relevant: which risk factors are known for the development of RA? How can these risk factors be combined in a risk model for the prediction of RA? Which persons have an increased risk to develop RA? To answer these questions, we reviewed in chapter 2 and 3 the data from studies on risk factors for de- veloping RA. Risk factors for RA include among others family history, high birth weight, smoking, silica exposure, alcohol nonuse, coffee consumption, sugar-sweetened soda intake, physical inactivity, obesity, diabetes mellitus, sleep disorders, thyroid disease, the presence of autoantibodies and genetic variants. Several risk models have been published. However, the measured risk is a life-time population risk, hence, for an indi- vidual person at risk this is difficult to interpret. Currently, no drug or other intervention exists with proven efficacy in the at-risk phase to prevent the development of RA. How- ever, certain lifestyle changes may provide a risk reduction, such as smoking cessation, dietary changes, and weight reduction.
Another relevant question is when to speak of ‘early RA’ and when of ‘established RA’ and can this transition be prevented? In chapter 3 we argue that there is no biological basis for a ‘phase of transition’ from early to established RA. The pathology already starts before the onset of early RA, which suggests that the onset of chronic inflamma- tion also takes place before the onset of clinically apparent arthritis. The immunological driving process of RA does not seem to differ between early and established RA, howev- er, it is well known that a better prognosis can be obtained with an early diagnosis and early aggressive treatment.
PART II: CARDIOVASCULAR RISK IN EARLY RHEUMATOID ARTHRITIS
In part II we focused on cardiovascular (CV) disease, a comorbid condition in RA patients,
as the inflammation not only affects the joints, but also the cardiovascular system. In 9 chapter 4 the presence of an unfavorable body composition was analysed in early ar-
thritis patients and compared to the general population. We analyzed 317 dual-energy
x-ray absorptiometry (DXA) scans of patients at the onset of arthritis and compared
them with 1268 age-, gender- and ethnicity-matched non-arthritis scans of controls. A
low muscle mass for ages was 4-5 times more common in early arthritis patients than in
controls. Furthermore, in early arthritis patients an unfavorable body composition was associated with a higher blood pressure and an atherogenic lipid profile, indicating an
SUMMARY
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