Characterization of relations among sleep, inflammation, and psychiatric dysfunction in depressed youth with Crohn disease

Abstract

Objectives: Recent reports demonstrate a link between inflammatory bowel disease (IBD) and sleep disturbance. Increased psychiatric dysfunction is consistently reported in patients with IBD. Our objective is to examine relations among sleep disturbance, inflammation, and psychiatric dysfunction in a pediatric population with Crohn disease (CD) and depression.

Methods: Pediatric patients with CD with depression (n = 96) and healthy controls (n = 19) completed measures of sleep (Pittsburgh Sleep Quality Index [PSQI]), depression, anxiety, and abdominal pain, and provided blood for inflammatory markers. CD activity was determined by the Pediatric Crohn's Disease Activity Index. Factor analysis was performed on subscales of the PSQI to derive measures of sleep disturbance. Univariate and multivariate regression analyses assessed relations between sleep disturbance, psychosocial, and biological measures of CD and psychiatric dysfunction.

Results: Sleep disturbance in depressed youth with CD was significantly greater than healthy controls, and was significantly related to measures of abdominal pain, depression, and anxiety, but not biomarkers of inflammation. Factor analysis of the PSQI demonstrated a 2-factor solution. The first factor, termed "Qualitative," included Subjective Sleep Quality, Daytime Dysfunction, Sleep Disturbance, and Sleep Latency, whereas the second factor, "Quantitative," consisted of Habitual Sleep Efficiency and Sleep Duration. This factor showed a significant relation to inflammatory markers. Multivariate modeling suggested that qualitative sleep disturbance was predicted by disease activity, pain, and anxiety, whereas quantitative sleep disturbance was predicted by disease activity.

Conclusions: These results indicate that sleep disturbance in depressed youth with CD differs depending upon illness activity. Patients may require different interventions depending upon the sleep disturbance exhibited.

Figure 1. PSQI Sleep Component Subscores by Frequency in Pediatric Patients with CD and Depression

The frequency of patients with disturbance in each of the 7 subscales of the PSQI is shown above (0 = no disturbance, 3 = severe disturbance). Note the proportional similarity in Sleep Duration and Habitual Sleep Efficiency, as these two subscales cluster together to form the basis of the Quantitative factor. As might be expected in a pediatric population, the Use of Sleeping Medications is minimal.

Figure 2. Putative Models of the Relationships Between Sleep, Inflammation, and Neuropsychiatric Dysfunction in CD

A. This figure illustrates a model whereby sleep disturbance contributes to inflammation and these two factors exert positive feedback upon one another, resulting in increasing CD severity. Sleep disturbance and psychiatric dysfunction have the capacity to worsen one another as well. B. In this panel, sleep disturbance, inflammation, and psychosocial dysfunction are separate entities, and each has the potential to impact one another directly. Thus, treatment of any one of these entities has the potential to improve the other two corners of the triangle. While treatment of the inflammatory and psychosocial components are the mainstay of managing CD, sleep disturbances are often neglected but may represent another means to effect improvement in this illness.