The variability of rheumatoid arthritis - Balancing between population and individual
The PhD defence of Letty Versteeg will take place (partly) online and can be followed by a live stream.
Letty Versteeg is a PhD student in the research group Psychology, Health & Technology. Supervisor is prof.dr. M.A.F.J. van der Laar and co-supervisors are prof.dr. H.E. Vonkeman and dr. P.M. ten Klooster, all from the Faculty of Behavioural Management and Social Sciences (BMS).
Rheumatoid arthritis (RA) is the most common form of inflammatory arthritis and, if left untreated, causes irreversible joint damage and disability. Together with pain and fatigue, this may lead to reduced quality of life in many patients.
By diagnosing RA in the early stages of the disease and starting treatment immediately, outcomes have improved enormously. Also, the application of treatment strategies in which disease activity is measured frequently and treatment is adjusted until a predefined level of disease activity is achieved (treat-to-target [T2T]), has shown excellent results in clinical trials.
To evaluate the feasibility of T2T strategies in daily clinical practice, an ongoing registry was initiated in which all patients diagnosed with RA were enrolled and followed up. This thesis describes the effects of T2T implementation in real world. Associations between disease activity, joint damage and fatigue have been evaluated at group level and within individual patients.
The studies show that continuous T2T treatment resulted in sustained low disease activity, improved physical function and higher quality of life in most patients. The long-term development of joint damage was limited and could be further delayed in the first year of treatment by intensifying combinations and dosages of antirheumatic drugs.
Despite good suppression of disease activity, a small proportion of patients developed progressive joint damage. Anti-CCP positivity, baseline erosive disease and the progression of damage within the first 6 months of treatment were associated with long-term joint damage. The association between disease activity and joint damage was found to be different for each patient, but correlated over time within individual patients.
Statistical methods that distinguish associations between individuals from associations within individuals have been used to study the correlation between disease activity and fatigue. In some patients, disease activity led to increased fatigue, but in other patients this association was absent or negative.
The results of this thesis add to the evidence for the globally accepted T2T strategies, but suggest that to further optimize care for RA patients, the focus should be shifted to individual patients. Optimal care for an individual patient comes from the knowledge and experience of large populations, but these will have to be applied in the unique context of each individual.
