Des travaux récents ont montré que les troubles du sommeil avaient des conséquences négatives sur la condition médicale des maladies inflammatoires comme les Maladies Inflammatoires Chroniques de l’Intestin. En plus de l’activité clinique de la maladie, les troubles du sommeil sont fréquemment associés à la dépression et l’anxiété qui sont par ailleurs fréquentes au cours des maladies chroniques. Lorsqu'un patient se plaint d’avoir un mauvais sommeil ou de fatigue, sa situation étant complexe et multidéterminée, il peut être difficile d'identifier sa cause la plus probable et d'établir la meilleure intervention thérapeutique possible. L’objectif de ce travail était de déterminer quelles étaient les variables les plus discriminantes des perturbations du sommeil. Quatre-vingt-dix-sept patients atteints d’une maladie de Crohn (CD) consultant en ambulatoire et se plaignant d’être fatigués ont été interrogés sur leur sommeil (IQSP, ISI, échelle de somnolence diurne) et leur humeur (HADS). Ils ont aussi rapporté les informations concernant l’activité clinique de la maladie (indice de Harvey-Bradshaw) et la CRP (inflammation). Les résultats montrent un lien plus faible entre l'inflammation et les troubles du sommeil que d'autres études mais ils confirment le lien entre les troubles du sommeil et l'activité de la maladie. Dans une activité de pratique psychologique, l’évaluation des troubles du sommeil pourrait constituer une approche commune au médecin et au psychologue, pour la prise en charge des patients atteints de CD et de leurs symptômes associés. Afin de prédire la probabilité et la nature des rechutes, il semble important que les futures recherches prennent en compte non seulement l'activité de la maladie et l'inflammation, mais aussi les troubles de l'éveil et les réveils des patients.

Research has shown that sleep disturbances can negatively influence the progression of chronic inflammatory diseases, including chronic inflammatory bowel disease (IBD). More specifically, poor sleep quality is strongly related to the clinical activity of the disease. Nevertheless, some patients suffer from sleep disorders even when the disease is clinically inactive. Psychological factors, such as depression and anxiety, are also known to contribute to poor sleep quality. Depression and anxiety are common in chronic diseases. In addition, while the link between depression or anxiety and sleep disorders is well-known, the link between sleep disorders and inflammation has only been studied recently. Sleep studies in IBD patients have generally excluded patients with clinically diagnosed depression or anxiety in order to neutralize their effects on the relationship between inflammation and sleep disorders. Nevertheless, there is no consensus on the relationship between depression and anxiety and the clinical activity of the disease. When a patient with chronic inflammatory bowel disease (Crohn's disease here) complains of fatigue or poor sleep, the subjective aspects of these complaints therefore lead the clinician to consider them simply as: a characteristic of IBD, exhaustion related to the chronicity of the disease, unsatisfactory sleep quality, a manifestation of a depressive mood, or a consequence of an anxious state. When a patient reports a subjective complaint of poor sleep or fatigue in a complex, multi-determined clinical situation, it can thus be difficult to identify its most likely cause and to establish the best possible therapeutic intervention.

The aim of this work was to determine which element (disease activity, inflammation, depression, anxiety) is most closely related to sleep disorders in patients with Crohn's disease (CD) referred for outpatient psychological assessment. Ninety-seven patients with CD participated in this study. Their mean age was 34.70 (±10.85) years. They were asked about their sleep (IQSP, ISI, ESD) and mood (HADS). They also provided details of clinical disease activity (Harvey–Bradshaw Index) and inflammation (CRP). In order to determine the nature and extent of the relationship between the variables, Spearman correlation coefficients were calculated, supplemented by multiple regression analyses to determine the variables that could explain the sleep disorders.

The results show that sleep quality (IQSP) was significantly predicted by the Harvey–Bradshaw score (β=0.21; β standardized=0.24; t=2.6; P=0.01) and depression (β=0.45; β standardized=0.41; t=4.55; P<0.001). The Harvey–Bradshaw score (β=26; β standardized=2; t=2.27; P=0.026) and depression score (β=75; β standardized=47; t=5.34; P<0.001) were related to the insomnia score (ISI). Finally, daytime sleepiness (DSA) was predicted by the depression score (β=42; β standardized=432; t=3.17; P=0.002) and by the CRP (β=−0.05; β standardized=−0.21; t=−2.13; P=0.036). The results show that the severity of clinical activity of the disease was associated with poor sleep quality and insomnia. However, there was a stronger association between the intensity of depression and sleep disturbances than between these variables and clinical disease activity. It therefore seems important that sleep disorders and their management should be considered first from the perspective of depression. However, it is important that CD is not assumed to be the sole cause of depression: other factors (dispositional or situational) should also be taken into consideration. Nevertheless, while our results show a weaker link between inflammation and sleep disorders than other studies, they confirm the link between sleep disorders and disease activity.

In order to predict the likelihood and nature of relapses, it seems important that future research should take into account not only disease activity and inflammation, but also disorders of arousal and nocturnal awakenings experienced by the patient.