Association between serum vitamin D levels and age in patients with epilepsy: a retrospective study from an epilepsy center in Saudi Arabia

Abstract

BACKGROUND: Vitamin D deficiency has been linked to various medical conditions such as bone loss, decreased mineralization, endocrine disorders, and central nervous system disorders, including epilepsy. Vitamin D deficiency is prevalent among patients with epilepsy (PWE). However, the specific association between vitamin D levels and age in PWE is unclear. OBJECTIVES: Identify the relation between vitamin D level and age in PWE and evaluate factors that may play a role in seizure control. DESIGN: Retrospective analytical medical record review SETTING: Outpatient epilepsy research clinic in Saudi Arabia PATIENTS AND METHODS: Between November 2016 and April 2020, we selected eligible PWE aged older than 14 years whose vita-min D levels were recorded at least once after reviewing 1550 patient electronic files. We analyzed data on serum vitamin D level by age and other factors, vitamin D supplement use, seizure classification, and conducted a multivariate logistic regression to assess associations with seizure control. MAIN OUTCOME MEASURES: Relationships between vitamin D levels and age and factors that might affect seizure control. SAMPLE SIZE: 524 patients RESULTS: The prevalence of low serum vitamin D levels was high (86.8%). The median vitamin D level in all patients was low (38 nmol/L), and was lower in young PWE than in adult PWE ( P <.01). Only 146 patients received vitamin D supplements. High vitamin D levels were associated with a 40% seizure reduction. CONCLUSION: Vitamin D deficiency is underestimated in PWE in Saudi Arabia, and is more prevalent among young adults and patients on polytherapy than in other PWE. Patients with high vitamin D levels had good seizure control compared with those with low levels. The effect of vitamin D supplements on seizure control should be further investigated in randomized control trials. LIMITATIONS: Retrospective study and no categorization by presence of supplementation. CONFLICT OF INTEREST: None.

Nutritional interventions for the prevention and treatment of neurological disorders such as anxiety, bipolar disorder, depression, epilepsy, multiple sclerosis, and schizophrenia

“…However, although some studies of patients with epilepsy have identi ied a therapeutic bene it of vitamin B6 supplementation in terms of improved clinical outcomes, this is not the case for every patient [212][213][214][215][216][217][218]. Multiple studies have identi ied vitamin D de iciencies among pediatric and adult patients with epilepsy [219][220][221][222]. In one clinical trial involving 23 patients with epilepsy administered 4,000 IU/day of vitamin D3 was for 4 weeks followed by 16,000 IU/day for 4 weeks to one group and a placebo followed by 8,000 IU/day of vitamin D3 to another.…”

Comment on: Association between serum vitamin D levels and age in patients with epilepsy: A retrospective study from an epilepsy center in Saudi Arabia

“…The high serum VD levels were correlated with a 40% seizure reduction. 1 Apart from a few study limitations stated by Alhaidari et al, 1 we believe that the following limitation is worthy to mention. Several factors could control the cutoff values (CV) of serum VD level.…”

“…That methodological limitation might importantly query the correctness of the study results. We believe that employing local CV of serum VD level might better fill the objectives of the study by Alhaidari et al 1 …”

“…To the Editor: In the July-August 2022 issue of the Annals of Saudi Medicine, Alhaidari et al 1 studied the relationship between serum vitamin D (VD) level and age among Saudi patients with epilepsy (PWE) and evaluated factors that might control the seizures. They found a high prevalence of VD deficiency (86.8%).…”

“…3 , 4 Saudi Arabia is among the countries that have generated their CV of serum VD levels and the recommended value for determining VD status and bone health was set at 30.0 nmol/L. 5 In the study methodology, Alhaidari et al 1 mentioned that serum VD level was grouped into normal (≥75 nmol/L) and low (<75 nmol/L). However, they didn’t state the reference of their utilized CV of serum VD levels.…”