The aim of the present study is to contribute to the literature on childhood rheumatoid disease by thoroughly investigating the cognitive profile of the children with JIA and estimating the potential for academic achievement of JIA patients. Our results highlighted preserved cognitive abilities, social cognition and implicit memory, and similar skills required to succeed academically in JIA patients and their peers. Importantly, this is the first time social cognition and implicit memory have been assessed in this population of patients. Early social cognition, for example, as the ability to understand other people’s points of view and feelings, predicts children’s subsequent school achievement and this pathway is mediated by children’s level of social competence.32 Implicit memory is also essential in learning and robust to cognitive disturbances. Research has shown preserved implicit memory in elderly and children with mental retardation.33,34 As the population of JIA children could have cognitive impairments, exploring implicit memory is essential. In order to thoroughly measure verbal and nonverbal implicit memory, we used experimental priming paradigms leading us to create two new tasks, a word completion task and a fragmented picture tests. The results of the cognitive profile and estimated academic achievement appear to be consistent since the cognitive functions are an important predictor of academic achievement, especially general intelligence and working memory.18 Our results stand in apparent contradiction with literature that suggests impaired life conditions in adult patients with JIA. Three complementary interpretations may account for this discrepancy.
First, the developmental perspective according to which cognitive impairments develop later in a patient's life should be taken into consideration. Our results are in line with a previous study indicating a normal intellectual quotient in children with JIA,20 even though another body of evidence suggests potential neurocognitive impairment in these patients, whether directly or indirectly linked to the clinical manifestation of the disease process.3 Specifically, the maturation of the CNS is subject to the consequences of various symptoms of JIA including the inflammation inherent in JIA,4–6 the long-term medication,7–9 reduced quality of sleep, 12,13 as well as the pain related to the disease.11 In 2014, a review put forward the idea that children with JIA experience long-term changes to the CNS that could last into adulthood, resulting in lowering of the threshold of pain tolerance often associated with the inflammation.35 In this perspective, a research assessed the cognitive aptitudes of 121 adult patients with rheumatoid arthritis.36 Their results indicated that chronic pain, mediatised by depression, leads to impairment of cognitive functions, particularly the speed of information processing, reasoning ability, working memory and long-term memory. Importantly, these consequences depend on the duration and severity of the disease.37 This set of findings is consistent with our results in assuming that while children with JIA are cognitively preserved, neuropsychological impairment may manifest itself later due to a lasting alteration of the CNS.
Second, in addition to the neurological factors, the psychosocial determinants should be considered from a developmental perspective. Our results on the estimation of school achievement are only based on standardized literacy and mathematic tasks, which might not reveal the real school achievement of such children. It has been shown that, at most, 50% of the variance in academic outcomes was explained by the cognitive abilities of the students.18 In other words, psychosocial factors may affect the deployment of the full cognitive capacities of JIA patients in a non-negligible way. Two factors are identified in the literature as particularly important. In the first place, the psychological resources required to cope with a chronic illness were investigated in JIA patients mostly based on the parents’ reports.16,17 The results mainly put forward that the burden of a chronic disease has a negative impact on emotional adjustment to social life,38 including school.39,20 Moreover, the constraints of coping with the disease and its symptoms means these children are more often absent from school than their classmates, disrupting both learning and their integration in the class.19 Consequently, students with JIA are twice as likely to fail at school than their peers.19 Next, a substantial literature on social psychology has highlighted subtle negative reactions from teachers towards the inclusion of students with disability.40,41 Yet the teacher's perceptions have an important impact on students’ academic success,31 especially when the disability is invisible42 as is the case with JIA. While academic achievement is an important predictor of well-being in adulthood,43 the quality of life of adults with longstanding JIA was found to hampered and was accompanied by a lower unemployment rate than in the general population.37 All these studies support the hypothesis that JIA children face subtle psychosocial barriers to the full expression of their cognitive abilities in the long term.
Although the size of our sample did not allow us to test the above-mentioned developmental hypotheses, further research should deepen these two perspectives. Research is also needed to more directly explore the factors that contribute to the emergence of factors that may threaten the quality of life (e.g., age, socio-economic status, perception of disability). Longitudinal methodologies would be particularly suitable since they would enable investigation of the precise factors leading to the deterioration.
Third, it should be noted that the patients in our study belonged to families involved in associations and who are highly committed to their children’s education. The sociodemographic data confirm that most of the children with JIA in our study came from upper-middle and upper class families. For this reason, it is difficult to extrapolate our results to all children with JIA, since our sample was small and the majority of the patients were recruited on a voluntary basis. While this did not bias our results as the JIA and the control groups were matched, it may have skewed the results by representing predominantly socially advantaged backgrounds. Indeed, the family’s socioeconomic status is known to play an important role in a child's academic achievement,44 and may explain why JIA children performed as well as their control peers in the academic tasks. Thus, following our first two interpretations, our results suggest that these children are less at risk of developing cognitive disorders later if they have such strong support from their families than most patients with JIA.