Introduction: There are many reports describing the association of alternations of bone and mineral metabolism in patients with epilepsy receiving long term anticonvulsant therapy. However, there are only a few Indian studies which have looked at this aspect. Objective: This study was done to compare the prevalence of changes in bone mineral parameters and bone mineral density (BMD) in ambulant individuals on long term anticonvulsant therapy with age and BMI matched healthy controls.
Methods: There were 55 cases and 55 controls. Both groups were matched for age, sex and BMI. Drug history, dietary calcium intake and duration of sunlight exposure were recorded. Serum alkaline phosphatase, albumin, creatinine, 25(OH)vitamin D and intact PTH were measured. BMD was assessed by using the DXA scanner at the lumbar spine and the femoral neck.
Results: The mean age ±SD in the cases and controls were 27.7 ± 7.9 and 29 ± 7.5 years respectively (P=0.11). The control group had a significantly higher daily dietary calcium intake with mean ±SD of 396 ±91 mg versus 326 ±101 mg (P=0.007) and more sunlight exposure of 234±81 vs 167±69 minutes (P=0.05). BMD at the femoral neck was significantly lower in cases (0.783±0.105 gm/cm2) when compared to controls (0.819±0.114 gm/cm2). There was no significant difference in the proportion of subjects with vitamin D deficiency (<20 ng/ml) between cases (n=32) and controls (n=37) (P=0.234).
Conclusions: Though sunlight exposure was significantly higher in controls when compared to cases, vitamin D deficiency was seen in both the groups in equal proportions, highlighting the existence of a high prevalence of vitamin D deficiency in the Indian general population. However, low femoral neck BMD found in cases when compared to controls stresses the importance of supplementing calcium and treating vitamin D deficiency in this specific group.
Declaration of interest: There is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.
Funding: No specific grant from any funding agency in the public, commercial or not-for-profit sector.