Vitamin B12 deficiency, restless legs syndrome and poor sleep quality in adolescents: A cross-sectional study.

Although the role of dopaminergic dysfunction and iron metabolism in the pathophysiology of restless legs syndrome (RLS) has been widely investigated, the potential association between vitamin B12 status and RLS remains insufficiently explored. In particular, data in pediatric and adolescent populations are limited and inconsistent. Moreover, while sleep disturbance is a well-recognized feature of RLS, the combined relationship between vitamin B12 levels, RLS, and sleep quality has not been adequately evaluated in adolescents. Therefore, the present study aimed to investigate the association between vitamin B12 levels and the presence of RLS, and to assess sleep quality in adolescents with and without RLS. Dysfunction of the dopaminergic system is known to play a role in the pathophysiology of patients with restless legs syndrome (RLS). Vitamin B12 functions as a cofactor in pathways involved in dopamine synthesis. This study was conducted to investigate the association between vitamin B12 levels and restless legs syndrome (RLS) and to evaluate the relationship between RLS and sleep quality. The study was conducted with 146 pediatric patients aged 10-16 years who applied to pediatric outpatient clinics. All patients were evaluated for RLS according to the diagnostic criteria established by the International RLS Study Group (IRLSSG). Patients with symptoms of RLS were scored using the disease symptom severity scale defined by the same group, and comparisons were made between the groups. To assess sleep quality, the Pittsburgh Sleep Quality Index (PSQI) questionnaire was administered to all patients, and the results were recorded and compared across all groups. There were no statistically significant differences in hemoglobin, hematocrit, ferritin, folic acid, or glucose levels. Serum vitamin B12 levels were found to be significantly lower in patients with RLS compared to those without the syndrome. Our total PSQI scores were statistically higher in the RLS group than in the non-restless legs syndrome group. Patients were divided into three groups according to their vitamin B12 levels: "deficient," "borderline," and "sufficient." When these three groups were compared in terms of the frequency of restless legs syndrome, its prevalence was statistically higher in the group with insufficient vitamin B12 levels. Conclusion: Our findings suggest an association between lower vitamin B12 levels and the presence of RLS in adolescents. However, due to the cross-sectional design of the study, causality cannot be established and further prospective studies are needed to confirm these findings. In addition, consistent with the literature, sleep quality was found to be impaired in patients with RLS in our study. What is known • RLS is associated with sleep disturbance and reduced quality of life • Evidence on the relationship between vitamin B12 and RLS is limited, especially in adolescents What is new • Lower vitamin B12 levels were associated with a higher frequency of RLS in unadjusted analyses • Vitamin B12 status may be related to sleep quality in this population.