HOUSTON – Neurologists and other clinicians ordered vitamin D levels, dual-energy x-ray absorptiometry (DXA) scans, and vitamin D supplementation for epilepsy patients in order to diagnose and prevent vitamin D deficiency and osteopenia, results from a single-center study showed.
Vitamin D deficiency and osteopenia are well described in the literature for patients on enzyme-inducing antiepileptic drugs (EIADs), but no guidelines currently exist for when to order tests or supplementation for patients on EIADs or non–enzyme inducing antiepileptic drugs (NEIADs). “Further studies with larger sample sizes will be helpful in order to establish guidelines for neurologists and other physicians,” Sher Afgan, MD, said in an interview at the annual meeting of the American Epilepsy Society.
Dr. Sher Afgan
Dr. Afgan, a research assistant at Drexel, went on to report that neurologists ordered vitamin D levels in 22% of patients; another 12% had already been ordered by another physician. Neurologists were more likely to order vitamin D levels for patients on EIADs, compared with those on NEIADs (32% vs. 10.4%; P less than .001), and vitamin D levels were more likely to be ordered by either neurologists or other physicians for patients on EIADs, compared with those on NEIADs (41% vs. 26%; P = .02). Neurologists ordered DXA scans in 22% of patients, and more often for those on EIADs, compared with those on NEIADs (33% vs. 10.4%; P less than .001). Similarly, DXA scans were more likely to be ordered by either neurologists or other physicians for patients on EIADs, compared with those on NEIADs (35.3% vs. 18.2%; P = .006). Supplementation was ordered in 23% of patients and was more likely to be ordered by neurologists for patients on EIADs, compared with those on NEIADs (36% vs. 8%; P less than .001).
The researchers also found that neurologists were more likely to order vitamin D levels, DXA scans, and supplements for men on EIADs, compared with women on EIADs (odds ratio, 2.178, P = .03; OR, 2.31, P = .02; OR, 1.87, P = .09, respectively). Generalized epilepsy did not significantly account for increases in ordering vitamin D for EIADs. Median total vitamin D levels were lower in patients on EIADs, compared with those on NEIADs (29 vs. 18 ng/mL; P = .03), but age and body mass index were not different among patients for whom neurologists ordered Vitamin D levels, DXA scans, or supplementation.
Dr. Afgan acknowledged certain limitations of the study, including its retrospective design and small sample size. “Also, type and duration of epilepsy, type and duration of antiepileptic drugs, and comorbidities should be considered in further studies with larger sample sizes,” he said. He reported having no financial disclosures.