Page 149 - Recognizing axial spondyloarthritis - Janneke de Winter

Recognizing the preclinical phases of axial SpA
Studying the preclinical phase of axial SpA is of major importance. Identifying patients even before the onset of symptoms might 1) reveal the pathogenic onset of inflammation and new bone formation, 2) help to identify diagnostic biomarkers and 3) enable us to treat at-risk individuals very early in the course of the disease or even before the onset of symptoms, to prevent structural damage to occur. In Chapter 7 we report the baseline characteristics of the first 51 seemingly healthy first-degree relatives of HLA-B*27 positive AS patients, the Pre-SpA cohort. A major conclusion is that at baseline 33% of first-degree relatives have clinical and/ or imaging features that allow a classification of SpA according to the ASAS axial SpA and/or ESSG classification criteria. The Pre-SpA cohort is to our knowledge a unique inception cohort, showing that a major part of seemingly healthy first- degree relatives already has SpA features. Future follow-up will identify first-degree relatives developing full-blown disease and possibly define predicting biomarkers in retrospect.
The study described in Chapter 8 explored the fictitious willingness of first- degree relatives of axial SpA patients, who are participating in the Pre-SpA cohort study to use preventive medication. When the axial SpA risk is clearly increased (70%) or when preventive medication has no side effects, the vast majority of first- degree relatives of axial SpA patients seems willing to use preventive medication. This willingness roughly drops by 50% by the possible occurrence of mild side effects. Secondly, the willingness to use preventive medication is influenced by the participants’ own perception of the severity of the disease and the disease risk, regardless of the given hypothetical risk.
In contrast to rheumatoid arthritis (39), in spondyloarthritis no previous studies explored the willingness of individuals at increased risk for axial SpA to start preventive medication, merely because of the difficult diagnostic process. The Pre-SpA cohort enabled us to study the willingness of seemingly healthy first- degree relatives of axial SpA patients to use preventive medication. Which is of importance, since today’s research increasingly focuses on the early detection and treatment, or even prevention of disease and/or structural damage. The data of our study suggest that the willingness of at-risk individuals is substantial, and might even increase if physicians emphasize the severity and risk of axial SpA to at-risk individuals. The importance of these results is supported by data showing that a delayed start of treatment is linked to worse clinical outcome (40,41). In recent years, the general research focus has shifted from suppressing symptoms to preventing structural damage, aided by the shortening of the diagnostic delay (23,24,42) and the ongoing development of biologics targeting the early disease process. And although these results encourage early or even preclinical therapeutic studies, some comments are in place. First, the fictitious willingness of a healthy first-degree relative might differ significantly from the willingness of at-risk individuals to actually start using medication. Second, several scenarios in our study suggested that the preventive medication guaranteed not to cause any side
GENERAL DISCUSSION AND SUMMARY
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