Madhava Vijayakumar1, Ajitha Bk2, Biju George3, Vijayalakshmi Bhatia4. 1. Department of Pediatrics, Government Medical College, Manjeri, Kerala, India. 2. Department of Gynecology, Government Medical College, Kozhikode, Kerala, India. 3. Department of Community Medicine, Government Medical College, Kozhikode, Kerala, India. 4. Department of Endocrinology. Sanjay Gandhi Postgraduate Institute of Medical Science, Uttar Pradesh, Lucknow, 222001, India. bhatiaviji@gmail.com.
Abstract
OBJECTIVE: To assess vitamin D status of children on long-term anticonvulsants, including the less studied widely used levetiracetam, and the potential risk factors for deficiency. METHOD: Children on antiepileptic drugs (cases, n = 269) were compared with controls (n = 295) for serum biochemistry, 25OHD, parathormone (PTH), sun exposure, dietary calcium, and vitamin D intake. RESULTS: Cases had lower serum 25OHD [median (IQR) 18.4 (11.5-24.1) ng/mL] compared to controls [20.8 (15.4-26.2] ng/mL, p < 0.001), as well as more frequent vitamin D deficiency (25OHD < 12 ng/mL, 27.1%) and insufficiency (25OHD < 20 ng/mL, 57.6%) than did controls (11.2% and 46.1%, respectively). Significantly lower median (IQR) serum calcium [8.8 (8.1-9.4) vs. 9.2 (8.5-10.0) mg/dL], phosphorous [3.8 (3.3-4.2) vs. 4.7 (4.0-5.3) mg/dL), and higher PTH [58.4 (42.9-85.8) vs. 38.9 (24.6-55.5) pg/mL, p < 0.001 for all] and proportion of elevated alkaline phosphatase (11.2% vs. 5.1%, p < 0.01) was seen in cases versus controls. Vitamin D deficiency was present in 53.4% of children with cerebral palsy (CP) versus 19.9% in those without CP (p < 0.001). Serum 25OHD did not differ between patients on cytochrome P450 inducers versus noninducers, neither among the 3 major groups, users of carbamazepine, valproate, and levetiracetam. Logistic regression analysis showed serum 25OHD < 12 ng/mL to be independently influenced by case or control status, presence of CP, and season of sampling. CONCLUSION: Vitamin D deficiency is common with anticonvulsant therapy, especially in those having CP. In Kerala, the hot, dry season from March to May is protective.
OBJECTIVE: To assess vitamin D status of children on long-term anticonvulsants, including the less studied widely used levetiracetam, and the potential risk factors for deficiency. METHOD: Children on antiepileptic drugs (cases, n = 269) were compared with controls (n = 295) for serum biochemistry, 25OHD, parathormone (PTH), sun exposure, dietary calcium, and vitamin D intake. RESULTS: Cases had lower serum 25OHD [median (IQR) 18.4 (11.5-24.1) ng/mL] compared to controls [20.8 (15.4-26.2] ng/mL, p < 0.001), as well as more frequent vitamin D deficiency (25OHD < 12 ng/mL, 27.1%) and insufficiency (25OHD < 20 ng/mL, 57.6%) than did controls (11.2% and 46.1%, respectively). Significantly lower median (IQR) serum calcium [8.8 (8.1-9.4) vs. 9.2 (8.5-10.0) mg/dL], phosphorous [3.8 (3.3-4.2) vs. 4.7 (4.0-5.3) mg/dL), and higher PTH [58.4 (42.9-85.8) vs. 38.9 (24.6-55.5) pg/mL, p < 0.001 for all] and proportion of elevated alkaline phosphatase (11.2% vs. 5.1%, p < 0.01) was seen in cases versus controls. Vitamin D deficiency was present in 53.4% of children with cerebral palsy (CP) versus 19.9% in those without CP (p < 0.001). Serum 25OHD did not differ between patients on cytochrome P450 inducers versus noninducers, neither among the 3 major groups, users of carbamazepine, valproate, and levetiracetam. Logistic regression analysis showed serum 25OHD < 12 ng/mL to be independently influenced by case or control status, presence of CP, and season of sampling. CONCLUSION: Vitamin D deficiency is common with anticonvulsant therapy, especially in those having CP. In Kerala, the hot, dry season from March to May is protective.