Yves Dauvilliers1, Elisa Evangelista2, Regis Lopez3, Lucie Barateau3, Sabine Scholz2, Barbara Crastes de Paulet4, Bertrand Carlander2, Isabelle Jaussent5. 1. Department of Neurology, National Reference Network for Narcolepsy, CHU Montpellier, Hôpital Gui-de-Chauliac, France; INSERM U1061, University of Montpellier 1, Montpellier, France. Electronic address: ydauvilliers@yahoo.fr. 2. Department of Neurology, National Reference Network for Narcolepsy, CHU Montpellier, Hôpital Gui-de-Chauliac, France. 3. Department of Neurology, National Reference Network for Narcolepsy, CHU Montpellier, Hôpital Gui-de-Chauliac, France; INSERM U1061, University of Montpellier 1, Montpellier, France. 4. Laboratoire de Biochimie-Hormonologie, CHU Montpellier, Hôpital Lapeyronie, France. 5. INSERM U1061, University of Montpellier 1, Montpellier, France.
Abstract
OBJECTIVES: Narcolepsy type 1 (NT1) is considered to be an immune-mediated disease in which environmental factors, such as vitamin D, might play a major role. The association between NT1 and vitamin D deficiency has previously been reported. The aim of this case-control study was to reassess vitamin D levels in a large clinic-based adult and paediatric population of patients with NT1 by considering several potential confounding factors. METHODS: The serum level of 25-hydroxyvitamin D (25OHD) was measured in 174 Caucasian patients with NT1 and 174 controls. Demographic and clinical features, body mass index (BMI), Pandemrix® vaccination, age, and season at the time of blood sampling were recorded. Between-group comparisons were made using univariate and multivariate logistic regression analyses. When appropriate, interaction terms were tested using the Wald Chi-squared test. RESULTS: Age, BMI, and season of blood sampling were different between groups. Conversely, the 25OHD level and fraction of subjects with vitamin D deficiency (serum level <75 nmol/L: 46.6% of patients vs 48.3% of controls; <50 nmol/L: 20.7% vs 17.2%) did not differ between patients with NT1 and controls. Overall, vitamin D deficiency was more frequent in men, obese subjects, and in samples collected in winter, without any association with NT1. In the patients group, no significant association was found between vitamin D deficiency, NT1 duration and severity, treatment, and Pandemrix® vaccination. CONCLUSIONS: Vitamin D levels were not associated with NT1 in a large case-control population when potential demographic and clinical confounding factors were taken into account.
OBJECTIVES:Narcolepsy type 1 (NT1) is considered to be an immune-mediated disease in which environmental factors, such as vitamin D, might play a major role. The association between NT1 and vitamin D deficiency has previously been reported. The aim of this case-control study was to reassess vitamin D levels in a large clinic-based adult and paediatric population of patients with NT1 by considering several potential confounding factors. METHODS: The serum level of 25-hydroxyvitamin D (25OHD) was measured in 174 Caucasian patients with NT1 and 174 controls. Demographic and clinical features, body mass index (BMI), Pandemrix® vaccination, age, and season at the time of blood sampling were recorded. Between-group comparisons were made using univariate and multivariate logistic regression analyses. When appropriate, interaction terms were tested using the Wald Chi-squared test. RESULTS: Age, BMI, and season of blood sampling were different between groups. Conversely, the 25OHD level and fraction of subjects with vitamin D deficiency (serum level <75 nmol/L: 46.6% of patients vs 48.3% of controls; <50 nmol/L: 20.7% vs 17.2%) did not differ between patients with NT1 and controls. Overall, vitamin D deficiency was more frequent in men, obese subjects, and in samples collected in winter, without any association with NT1. In the patients group, no significant association was found between vitamin D deficiency, NT1 duration and severity, treatment, and Pandemrix® vaccination. CONCLUSIONS:Vitamin D levels were not associated with NT1 in a large case-control population when potential demographic and clinical confounding factors were taken into account.