This is the first study to describe the prevalence of unsuccessful transfer of care in a juvenile arthritis population. We found that over half of young patients transferred to an adult rheumatologist had inadequate follow-up for their arthritis over the ensuing two years. This finding is surprising, given that our patient population probably represented the more severe end of the spectrum of JIA. This was reflected by the over representation of the types of JIA which are more likely to persist into adulthood, or lead to long-term disability. In addition, there likely was a referral bias because the Montreal Children's Hospital is a tertiary care hospital and most patients were referred to adult rheumatologists affiliated with University hospitals.
The long-term care of adults with JIA presents a number of challenges which are unique to this patient population . The long-term consequences of JIA encompass both disease specific sequelae and decreased social and economic performance which may contribute to diminished quality of life . In many cases, coping strategies are not fully developed before adolescence and the formative years must be negotiated with a chronic disease in evolution .
There are a number of studies, which have now confirmed that a large percentage of young people suffering from JIA will continue to have active disease into adulthood. In a review of this topic by Kiem Oen, she concluded that JIA often extends into adulthood. She found that most remissions will occur within the first 5 years and that the probability of remission decreases progressively after that . In fact, the majority of adult patients studied did not meet criteria for disease remission. Similarly, a long-term follow-up study by Zak and Pedersen showed evidence for increasing disability and residua with increasing follow-up time. Moreover, over half of the patients studied reported arthritis related pain, including a proportion who fit criteria for disease remission .
Our proportion of unsuccessful transfer of 52% is strikingly similar to that described in a population of patients with congenital heart disease, with fewer than 50% having appropriate follow-up in the adult milieu . The patients studied were at high risk of arrhythmias and re-operation. Successful transfer of care was significantly related to the presence of documented recommendations and to patient beliefs that his/her care should continue into adulthood in a specialized center. Patients who had had more cardiac surgeries, those who had refrained from abusing substances, and those who had attended pediatric appointments alone were also more likely to be followed appropriately in the adult centers.
A similar rate of unsuccessful transfer was described in a study of patients with type 1 diabetes . In this study, the baseline drop out rate in the adult centers was 40%. The authors of this study were able to improve this rate to 11% by providing a cohort of young adults support in navigating in the adult health care system in the transition period between pediatric and adult care.
Every effort should be made to ensure that young adults with JIA have timely access to a rheumatologist in the event of a disease flare, in order to minimize their disease burden. We found an association between a low AJC at last pediatric clinic visit and an almost three-fold risk of unsuccessful transfer. This group of young adults with relatively inactive disease should be educated about the importance of ongoing follow-up in the adult milieu given the high possibility of active disease into adulthood.
The process of transitioning children to adult care should begin long before the time of transfer. The Canadian Pediatric Society's position statement, published in 2007 emphasizes the differences between the family focused pediatric care and the patient focused adult milieu . This different "culture" may play a role in unsuccessful transfers of care. The report highlighted the fact that many of the barriers to successful transfer are the same across a wide variety of chronic diseases [12–15]. Health care transition counseling with enhanced social support and self-management strategies may improve outcomes [16, 17].
Our study did have limitations. The retrospective cohort design of this study has some notable disadvantages. We were unable to track down a large number of patients in the cohort and we relied heavily on documentation in the charts to ascertain the transition plan. It is possible that lack of documentation led us to over-estimate the rate of unsuccessful transfer. For example, patients lost to follow-up or discharged from the JIA clinic may have sought follow-up in the adult milieu on their own. However, these transfers would have been suboptimal at best, with no transfer letter sent to the adult rheumatologist. We were also unable to evaluate several potentially important barriers to successful transfer of care, identified by Shaw . Those variables pertaining to adherence to treatment, pain, functional status, number of independent visits, psychosocial functioning, support system and economic factors should be evaluated prospectively. Additionally, the small study size may have impaired our ability to identify significant risk factors for unsuccessful transfer.
The proportion of subtypes of JIA differs in our study to the numbers described in the literature . There is a marked under-representation of oligoarthritis (18% compared to 27-56%) and an over-representation of enthesitis-related arthritis (24% compared to 3-11%), while the other disease subtypes are appropriately represented. This pattern may reflect the forms of juvenile arthritis which are more or less likely to persist into adulthood. We may have captured some patients who were labeled as ERA but later evolved to become inflammatory bowel disease-related arthropathy. Additionally, this population is drawn from a tertiary care centre which may skew the representation towards more serious cases of juvenile arthritis. It is interesting to note that, although not statistically significant, there was a trend towards less successful transfer of care in certain JIA categories (oligoarthritis, ERA) and successful transfer in systemic arthritis. The possible association between category of JIA and unsuccessful transfer of care should be addressed in future studies.
We found that those patients with less active disease, with an AJC of zero at the last clinic visit prior to transfer, were almost three times more likely to have an unsuccessful transfer to adult care. Alerting the pediatric team to the importance of educating the patients with less severe disease about the possibility of active disease into adulthood, and the importance of having follow-up with an adult rheumatologist is important. In our study, we noted a trend for young men to have unsuccessful transfers. Targeting this group may also be important to improving the follow-up of these patients.
The number of patients in each category of JIA was probably too small to allow for detection of differences between categories. Disease duration was perceived to be a risk factor for transitional difficulties in the study by Shaw. In our study, age of onset did not predict unsuccessful transfer of care; we used this variable as a surrogate for disease duration as most patients transferred in their nineteenth year. Because the treatment practices changed over the course of the time period covered by the study, use of DMARDs and biologic agents at the time of the transfer was not evaluated. Whether the patient had ever used DMARDs was evaluated as a marker of disease severity, but it did not significantly predict the outcome of unsuccessful transfer of care.
In conclusion, we found a dishearteningly high rate of unsuccessful transfer for pediatric to adult rheumatology care. Since this study was terminated, a dedicated young adult rheumatic disease clinic has been established within the McGill network. It is our hope that this clinic will be able to address some of the barriers to successful transfer of care. A follow-up study to test this hypothesis is planned.