Associations Between Vitamin D Status and Clinical Presentation Among French Inpatients With Substance Use Disorders

Numerous studies have demonstrated that vitamin D plays a crucial role in modulating dopaminergic pathways, suggesting a potential role in the pathophysiology of addictive disorders. However, among individuals with substance use disorders (SUDs), the link between vitamin D and addiction-related symptoms has not been sufficiently studied.

This study aims to explore among inpatients treated for various types of SUDs differences in addiction-related, psychopathological and biological characteristics based on vitamin D status.

The sample included 260 participants hospitalized in a French addiction treatment unit. Vitamin D concentration and other biomarkers, SUDs severity and other psychiatric disorders, cognitive functioning and impulsivity were collected at hospital admission (T0). Perceived negative affectivity and craving (for the main substance and food) were collected at T0 and hospital discharge (T1).

About 89.3% of the participants had a vitamin D deficiency as defined by French recommendations (< 30 ng/mL). Using univariate between-group analyses, vitamin D deficiency was associated with higher body weight and lower calcium plasma levels at T0, as well as increased craving intensity for both the substance at the origin of the treatment and food at T1. Multivariate regression analyses showed no significant associations between vitamin D or calcium levels and craving intensities at T1.

This study confirms the high prevalence of vitamin D deficiency among inpatients treated for SUDs. Although preliminary, our findings highlight the importance of assessing vitamin D levels in SUDs. They call for further research on its role in relapse vulnerability and the potential benefits of its supplementation during drug withdrawal treatment.