Sleep Disturbances and Vitamin D in Celiac Patients Under a Gluten Free Diet: A Cross-Sectional Study

Background: Celiac disease (CD) is an immune-mediated enteropathy associated with extra-intestinal manifestations. Sleep disorders may be frequent in CD patients. We aimed to investigate the quality of sleep in CD patients and to assess its relationship with clinical and biochemical parameters. Methods: We included patients with a proven diagnosis of CD under a gluten free diet at least twelve months prior to enrolment. All the participants completed the Sleep Scale from the Medical Outcomes Study (MOS sleep scale) and the Sleep Problems Index II was calculated. A high SLP9 score indicated a bad quality of sleep and values >20 revealed sleep disturbance. Moreover, blood samples were collected and demographic and clinical data were recorded from each subject. Linear logistic regression was used for uni- and multivariate analyses; the b coefficient and 95% confidence intervals (CI) were calculated. Results: We enrolled 53 patients, with the mean age being 42.75 ± 11.19 and 84.9% being females. The average hours of sleep per night were 6.47 ± 1.11. The mean SLP9 was 37.44 ± 20.65. Forty patients (75.5%) showed sleep disturbance, and 81.1% of patients had vitamin D insufficiency. According to univariate analysis, high SLP9 values (worse sleep) were inversely related to the number of sleep hours (b = −0.38, 95%CI: −11.8 to −2.2, p = 0.005) and to vitamin D levels (b = −0.57, 95%CI: −2.7 to −0.46, p = 0.009). In multivariate analysis only serum levels of vitamin D were inversely related to SLP9 (b = −0.47, 95%CI −12.8 to −0.43, p = 0.05). Conclusions: Low serum levels of vitamin D are independently associated with poor sleep quality in celiac patients. These findings need to be confirmed in future experimental and clinical studies.