Evaluation of bone mineral metabolism in children receiving carbamazepine and valproic acid

Effect of duration of sodium valproate therapy on bone mineral density and vitamin D levels

OBJECTIVE

This study aimed to evaluate the impact of prolonged sodium valproate use on bone mineral density (BMD) and Vitamin D levels in pediatric epilepsy patients.

METHODS

In a cross-sectional study conducted at the Epilepsy Clinic of Niloufer Hospital, Hyderabad, India, 50 pediatric patients (aged 4-10 years) were recruited. The cohort comprised 30 epilepsy patients on sodium valproate treatment (cases) and 20 healthy siblings without epilepsy or valproate use (controls). BMD was assessed using dual-energy X-ray absorptiometry to measure height-adjusted total body less head Z-scores (TBLH Z-scores), and serum 25-hydroxyvitamin D levels were measured. Statistical analysis included independent samples t-tests, Mann-Whitney U tests, and Pearson correlation, with a preliminary power analysis ensuring adequate sample size.

RESULTS

Cases exhibited significantly lower BMD TBLH Z-scores (Mean = -1.543) compared to controls (Mean = 0.515, p <.001) and reduced Vitamin D levels (Mean = 9.17 for cases vs. 27.80 for controls, p <.001). A negative correlation was observed between the duration of sodium valproate use and both BMD Z-scores (r = -0.626, p <.001) and Vitamin D levels (r = -0.707, p <.001).

CONCLUSIONS

The findings suggest a significant negative impact of prolonged sodium valproate use on both bone density and Vitamin D levels in pediatric patients. These results underscore the importance of monitoring and managing bone health in children receiving long-term sodium valproate therapy.

Evaluation of Bone Metabolism in Children Using Antiseizure Drugs: A Single-Center Experience and Review of the Literature

The effect of anti-seizure drugs (ASDs) on bone mineral density (BMD) is a controversial topic. This study investigated the effect of monotherapy and polytherapy drugs separately. Patients with a history of epilepsy treated with the same ASDs for more than 6 months were included in the study. Data regarding patient demographics, biochemical markers related to bone metabolism (calcium, phosphorus, alkaline phosphatase, parathyroid hormone, vitamin D), and BMD with dual-energy X-ray absorptiometry (DXA) were collected and compared. In total, 104 children with epilepsy using valproic acid (VPA), levetiracetam (LEV), carbamazepine (CBZ) alone or in combination and 22 healthy controls were evaluated. The ages of the children (64 boys, 62 girls) ranged between 2 and 17, with a mean of 9.50 ± 4.03 years. BMD or Z-scores did not differ among the monotherapy groups or between them and the polytherapy group. The lowest mean Z-score was in the VPA group but without statistical significance. Alkaline phosphatase levels were significantly higher in the group using CBZ. Calcium levels significantly differed between the groups (p = 0.001). The CBZ and LEV groups had the lowest calcium levels. However, phosphorus and vitamin D measurements did not significantly differ by ASDs used. Unfortunately, low vitamin D levels were evident in all children with epilepsy and even among controls. Physical activity, sun exposure, and calcium intake might be recommended in children treated with ACDs and in combination with additional risk factors monitoring via DXA should be considered. Further studies in a large population are necessary to judge which ASDs are more at risk to reduce bone mineralization than others.

The effect of carbamazepine on bone structure and strength in control and osteogenesis imperfecta (Col1a2 +/p.G610C ) mice

The inherited brittle bone disease osteogenesis imperfecta (OI) is commonly caused by COL1A1 and COL1A2 mutations that disrupt the collagen I triple helix. This causes intracellular endoplasmic reticulum (ER) retention of the misfolded collagen and can result in a pathological ER stress response. A therapeutic approach to reduce this toxic mutant load could be to stimulate mutant collagen degradation by manipulating autophagy and/or ER‐associated degradation. Since carbamazepine (CBZ) both stimulates autophagy of misfolded collagen X and improves skeletal pathology in a metaphyseal chondrodysplasia model, we tested the effect of CBZ on bone structure and strength in 3‐week‐old male OI Col1a2^+/p.G610C and control mice. Treatment for 3 or 6 weeks with CBZ, at the dose effective in metaphyseal chondrodysplasia, provided no therapeutic benefit to Col1a2^+/p.G610C mouse bone structure, strength or composition, measured by micro‐computed tomography, three point bending tests and Fourier‐transform infrared microspectroscopy. In control mice, however, CBZ treatment for 6 weeks impaired femur growth and led to lower femoral cortical and trabecular bone mass. These data, showing the negative impact of CBZ treatment on the developing mouse bones, raise important issues which must be considered in any human clinical applications of CBZ in growing individuals.

DK, Chaudhary DG. A Comparative Study of Serum 25-Hydroxy Vitamin D Levels in Children with Seizures Receiving Monotherapy and Polytherapy

The association between serum 25-hydroxy vitamin D (25(OH)D) antiepileptic drugs (AEDs) and bone health in individuals with epilepsy has been recognized for more than 30 years. Several studies indicate an increased risk for bone loss in patients on antiepileptic medication as well as low levels of serum 25(OH)D. Patients on polytherapy AED are at a higher risk of adverse drug effects compared with those on monotherapy. The present study assessed serum 25(OH)D levels in children receiving AED and compares those children receiving monotherapy versus polytherapy. This is a prospective cross-sectional study conducted in a tertiary care hospital setting on children with seizures receiving AEDs for period of more than 6 months. Participants were enrolled in three groups: 25 children on monotherapy, 25 children on polytherapy, and 25 healthy controls. Serum 25(OH)D level was performed for all children and analyzed. Serum 25(OH)D levels were normal in 52%, insufficient levels in 43.3%, and deficient in 6.7% of children. Vitamin D level was insufficient in 40% of children receiving monotherapy and 52% receiving polytherapy AED. Vitamin D deficiency was present in 4% in monotherapy group and 16% in polytherapy group which was statistically significant (p-value 0.047). Vitamin D deficiency was higher in children receiving AED compared with normal controls. Vitamin D deficiency and insufficiency were higher in children on polytherapy. Our study emphasized the importance of monitoring vitamin D levels in children receiving AED to detect abnormalities in vitamin D levels.

Impact of carbamazepine on vitamin D levels: A meta-analysis

PURPOSE

There are longstanding concerns about the impact of enzyme-inducing anti-seizure medications (ASMs) on vitamin D, an important molecule in both bone metabolism and inflammation pathways. The relationship between chronic use of carbamazepine and vitamin D levels has been studied, but no comprehensive review to inform practitioners and policymakers is currently available. We performed a meta-analysis on studies that measured 25-hydroxyvitamin D (25OHD) levels in persons taking carbamazepine to determine whether this drug significantly reduces circulating 25OHD.

PRINCIPAL RESULTS

From a literature search of the terms "carbamazepine" and "vitamin D", we identified 12 studies that measured 25OHD levels in persons on carbamazepine monotherapy groups and controls. Persons taking carbamazepine had significantly lower 25OHD levels than persons not taking carbamazepine. The average 25OHD levels of carbamazepine-treated patients across all studies was 21.8 ng/mL (IQR 15.4,26.0) whereas 25OHD levels of control subjects was 28.0 ng/mL (IQR 20.8,30.4). The weighted difference of means was 4.00 ng/mL of 25OHD. Neither age nor sex nor duration of carbamazepine therapy had a significant impact on this finding. The effect was similar irrespective of whether the comparator group consisted of healthy controls or epilepsy patients taking non-inducing medications.

MAJOR CONCLUSIONS

Carbamazepine use is associated with a reduction of 25OHD levels. In combination with other literature establishing the problematic metabolic effects of carbamazepine, this meta-analysis provides additional evidence in favor of the use of alternative ASMs as first-line agents. At minimum, vitamin D supplementation should be strongly considered for patients prescribed carbamazepine.

Vitamins K and D deficiency in severe motor and intellectually disabled patients

OBJECTIVES

We aimed to determine serum 25-hydroxyvitamin D (25(OH)D) and undercarboxylated osteocalcin (ucOC) levels in severe motor and intellectual disabilities (SMID) patients and their association with bone turnover biomarkers.

METHODS

We assessed vitamin D and K levels as indicators of osteoporosis in institutionalized adults with SMID. From December 2019 to February 2020, 93 institutionalized patients (48 men, 45 women; median age, 49 years) underwent annual routine examinations. Serum ucOC, 25(OH)D, bone-specific alkaline phosphatase (BAP), and tartrate-resistant acid phosphatase A 5b (TRACP-5b) levels as bone formation and resorption markers and calcium and phosphorous levels were measured. Vitamin K deficiency was indirectly assessed based on ucOC levels.

RESULTS

Mean ucOC levels were higher than normal (i.e., vitamin K deficiency). Serum 25(OH)D levels were markedly diminished. Overall, 86% of patients had deficient 25(OH)D levels. These 25(OH)D-deficient patients had higher ucOC levels. Multiple linear regression analysis revealed an inverse correlation between 25(OH)D and ucOC levels. ucOC levels were significantly higher and 25(OH)D levels were significantly lower in tube feeding. TRACP-5b levels were significantly higher in elderly than in young women. BAP and TRACP-5b levels were normal in adults. No relationship existed between vitamin D and antiepileptic drug use.

CONCLUSIONS

Vitamin K and D co-deficiency was common in SMID patients. Vitamin K and D deficiencies were worse in tube-fed patients than in oral intake patients. SMID patients should undergo regular monitoring of vitamin D and K levels and supplementation of these vitamins.

Effects of valproic acid on skeletal metabolism in children with epilepsy: a systematic evaluation and meta-analysis based on 14 studies

BACKGROUND

Previous studies have reported that long-term use of valproic acid can cause changes in bone metabolism in children. We conducted this meta-analysis to determine the effects of valproic acid on bone metabolism and bone mineral density (BMD) in children with epilepsy.

METHODS

Studies were searched from the databases of PubMed, Embase, Ovid, Cochrance Library, Springer Link and Web of Science. The effects of valproic acid on bone metabolism indicators and BMD were assessed through calculating the standardized mean difference (SMD) with 95% confidence interval (CI).

RESULTS

Fourteen studies with 987 individuals were included in this analysis. The long-term use of valproic acid did not affect the levels of serum calcium (p = 0.99), phosphorus (p = 0.28), ALP (p = 0.76), PTH (p = 0.36) and osteocalcin (p = 0.72), but it led to a decrease in 25-OH-VitD (p = 0.01) and BMD (p = 0.002 for the vertebra; p = 0.004 for the femur) in treating children with epilepsy.

CONCLUSION

Long-term use of valproic acid in treating children with epilepsy can lead to a reduction in 25-OH-VitD and BMD. Measurements of 25-OH-VitD and BMD should be performed regularly in children taking the drug to detect early osteopenia caused by the drug.

Osteoporosis pathology in people with severe motor and intellectual disability

OBJECTIVES

We assessed the severity and pathology of osteoporosis in children and adults with severe motor and intellectual disabilities (SMID) by evaluating bone enzymes, by which we aimed to determine adequate treatment approaches for preventing fractures.

METHODS

Ninety patients (44 men, 46 women; mean age, 34.5 years) underwent bone quality assessment. Quantitative ultrasonography (QUS) was used to measure the T-score and Z-score of the calcaneus, and blood tests were used to measure bone-specific alkaline phosphatase and tartrate-resistant acid phosphatase 5b levels as bone formation and resorption markers, as well as calcium, phosphorous, and parathyroid hormone levels as routine examination.

RESULTS

Bone formation and resorption marker levels were within normal ranges in adults, although they were high during the growth period in children and adolescents and in elderly women. Patients receiving tube feeding showed a significantly lower Z-score than those without tube feeding. Tube feeding was a significant factor for the Z-score, whereas age, vitamin supplements, and anti-epileptic drugs were not.

CONCLUSIONS

The severity of osteoporosis in SMID started during the growth period and seems to be caused by a lack of an effective increase in bone mineral density. Any treatment should be started during the growth period. More study about tube feeding is needed.

Effect of carbamazepine on the bone health of people with epilepsy: a systematic review and meta-analysis

Importance

Increasing evidence indicates that carbamazepine (CBZ) treatment in people with epilepsy (PWE) has adverse effects on bone health.

Objective

We conducted a meta-analysis to investigate the effect of CBZ on the bone health of PWE.

Methods

Two independent reviewers systematically searched PubMed and EMBASE for eligible studies. Standard mean deviations (SMDs) with 95% confidence intervals were used as a measure to investigate the effect of CBZ on bone-related outcomes in PWE.

Results

Levels of vitamin D (standardized mean difference [SMD]: −0.62, 95% CI: −0.89 to −0.35) and calcium (SMD: −0.38, 95% CI: −0.67 to −0.09) were significantly lower in the CBZ group than controls. Additionally, significantly higher alkaline phosphatase (SMD: 0.67, 95% CI: 0.52–0.82) was observed in patients using CBZ than controls. However, no significant difference in BMD was found between the two groups (SMD: −0.06, 95% CI: −0.55 to 0.43).

Conclusion and significance: This study provided evidence that CBZ treatment has a negative effect on bone health in PWE. Clinical implications are that long-term CBZ treatment may not be a good choice for PWE with skeletal diseases or osteoporosis.

Bone health in pediatric patients with neurological disorders

Patients with neurological disorders are at high risk of developing osteoporosis, as they possess multiple risk factors leading to low bone mineral density. Such factors include inactivity, decreased exposure to sunlight, poor nutrition, and the use of medication or treatment that can cause lower bone mineral density such as antiepileptic drugs, ketogenic diet, and glucocorticoids. In this article, mechanisms involved in altered bone health in children with neurological disorders and management for patients with epilepsy, cerebral palsy, and Duchenne muscular dystrophy regarding bone health are reviewed.

Bone Mineral Density Loss in People With Epilepsy Taking Valproate as a Monotherapy: A Systematic Review and Meta-Analysis

Objective: Data on changes in bone mineral density (BMD) from valproate (VPA) therapy are ambiguous and conflicting. Thus, the aim of this study was to systematically review the existing data and carry out a meta-analysis to investigate the effect of VPA as a monotherapy on BMD in people with epilepsy (PWE). Methods: We systematically searched PubMed, EMBASE, and MEDLINE for eligible studies. We calculated the standardized mean difference (SMD) with 95% confidence interval (CI) to investigate the statistical power of the association between VPA treatment and BMD. Results: Nineteen studies were included in this systematic review and meta-analysis. We found that BMD was lower in the VPA group than in the control group (SMD: -0.44; 95% CI: -0.65 to -0.22). A significant association was found in adult patients (SMD: -0.57; 95% CI: -0.88 to -0.26; I 2 = 69.8%) and pediatric patients (SMD: -0.32; 95% CI: -0.60 to -0.03; I 2 = 67.8%) by subgroup analysis. This study indicated that BMD was significantly lower in patients treated for more than 36 months than in controls (SMD: -0.52; 95% CI: -0.76 to -0.27; I 2 = 61.8%). However, a significant difference was not found between patients who were treated for less than 36 months and controls (SMD: -0.36; 95% CI: -0.72 to 0.01; I 2 = 74.8%). Conclusion and significance: The present study provided evidence that VPA treatment was significantly associated with BMD loss in PWE. Thus, for patients at a high risk of osteoporosis and fracture, especially for patients who need long-term treatment, VPA may not be a good choice.

Evaluation of bone health among epileptic patients using biochemical markers and DEXA scan: an Egyptian study

BACKGROUND

An association between antiepileptic drugs, low bone mineral density (BMD), fractures, and abnormalities in bone metabolism has been suggested for a longer period, although conclusive evidence has not been reported.

METHODS

Thirty epileptic patients and 30 matched healthy subjects participated in the study. Measurements of serum levels of calcium, phosphorus, vitamin D, parathormone, and alkaline phosphatase were done for included subjects. Dual-energy X-ray absorptiometry (DEXA) scan was also performed.

RESULTS

Serum calcium, phosphorus, and vitamin D were significantly lower, whereas serum parathormone and alkaline phosphatase were significantly higher in epileptic patients compared to control subjects. Bone mineral density (BMD) abnormalities were detected in 22 patients (73.4%). A statistically significant difference in DEXA scan measurements at different regions was detected between epileptic patients and control subjects. Epileptic patients receiving enzyme inducer antiepileptic drugs (AEDs) had significantly lower serum (calcium, phosphorous, and vitamin D) and lower BMD values compared to those receiving enzyme inhibitors. Results of BMD were positively correlated with serum calcium, phosphorous, and vitamin D, while negatively correlated with serum alkaline phosphatase and duration of therapy.

CONCLUSIONS

Abnormal bone health is common in epileptic patients. These abnormalities may be attributed to prolonged intake of AEDs especially enzyme inducers.

Decreased bone density induced by antiepileptic drugs can cause accelerated orthodontic tooth movement in male Wistar rats

PURPOSE

The aim of the present study was to evaluate the effect of the carbamazepine and valproic acid on orthodontic tooth movement in male Wistar rats.

METHODS

Evaluation of tooth movement after 21 days of drugs infusion was carried out by feeler gauge. Bone densitometry on lateral cephalograms was conducted on days 1 and 21. After dissection of the maxillae, histologic parameters were evaluated.

RESULTS

Orthodontic tooth movement was accelerated in experimental groups rather than controls. Optical density was significantly increased in these groups. In histologic sections, mesioapical portion of the PDL (Periodontal Ligament) was wider in experimental groups. Also, distoapical portion of the PDL was wider only in valproic acid group.

CONCLUSION

Valproic acid and carbamazepine can decrease the bone density which may induce the accelerated orthodontic tooth movement in rats.

Bone Mineral Status in Children with Epilepsy: Biochemical and Radiologic Markers

Objective:

The aim of this study is to assess bone mineral status in children with epilepsy, on different antiepileptic drugs (AEDs) regimen, using dual-energy X-ray absorptiometry (DXA) and routine biochemical bone markers.

Patients and Methods:

This is observational prospective controlled cohort study, conducted at Mansoura University Children Hospital, from January 2014 to June 2015. In this study, we had 152 participants with ages 3–13 years, 70 children diagnosed with epilepsy and 82 were controls. Children classified into two groups according to the duration of treatment, Group 1 children maintained on AEDs for 6–24 months, Group 2 children ≥24 months. Bone mineral density (BMD) measured by DXA and biochemical markers includes serum calcium, phosphorus, alkaline phosphatase (ALP), and parathyroid hormone (PTH).

Results:

In this study, we found that the serum level of calcium and phosphate were significantly low (P > 0.05) in total cases versus control. We found that the serum level of and ALP and PTH were significantly high (P > 0.05) in total cases versus control. Regarding the DXA markers, there was a significant decrease of BMD and Z-score for the total body and lumbar area in the total cases versus control (P > 0.05).

Conclusion:

The present study showed that all AEDs (new and old) affect bone mineral status in children receiving therapy for more than 6 months, altering both biochemical markers (serum calcium, phosphorus, ALP, and PTH) and radiologic markers (BMD assessed using DXA). Children on AEDs for a longer duration (≥2 years) showed more severe side effects on BMD. Children receiving multiple AEDs are more prone to altered bone mineral status, especially with long duration of therapy. The study also highlights the role of DXA as a safe noninvasive method to assess BMD in children on long-term AEDs.

Relationship between Bone Density and Biochemical Markers of Bone among Two Groups Taking Carbamazepine and Sodium Valproate for Epilepsy in Comparison with Healthy Individuals in Yazd

Introduction

Chronic antiepileptic therapy has been associated with metabolic bone diseases including osteomalacia and osteoporosis. The aim of this study was to determine frequency of changes in biochemical and bone mineral density (BMD) in adults receiving valproaic acid (VPA) & carbamazepine (CBZ).

Methods

In a cross sectional study evaluating adults (age 20–50 y) epileptic patients receiving valproic acid or carbamazepine for at least 2 years. This study was conducted from May 2014 to May 2015 in Shahid Sadoughi Hospital of Yazd University of Medical Science, Yazd, Iran. Bone metabolism was evaluated by measurement of serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP) and parathormone hormone (PTH), BMD at lumbar and femoral measured by dual energy X ray absorptiometry (DXA). SPSS software (version 18) was used for data analysis. The t-test was used for quantitative data, and the chi-squared test was used for the qualitative variables.

Results

Eighty two epileptic patients (mean age: 31.67±10.69 year) treated with either carbamazepine (n=41) or valproate sodium (n=41) were studied. Normal serum Ca and P levels were observed in 98.8% and 97.6% of patients respectively. Serum ALP and PTH were normal in 97.6% and 97.6% of patients. Means of Ca and P in CBZ group were significantly lower than VPA group (Ca: 9.02 vs. 9.1, p-value: 0.03 and P: 3.54 vs. 3.76 p-value: 0.004). BMD values at lumbar spine were not significant in either group (T. score CBZ: −0.43± 0.744 vs. T. score VPA: −0.615± 0.904 and p-value: 0.333) and were significantly higher than Iranian normal population BMD value at femoral neck in CBZ group was lower than VPA group (T. score CBZ: −0.707± 0.896 vs. T. score VPA: − 0.297± 0.850 p-value: 0.04). Dosage of CBZ and VPA did not correlate with BMD and biochemical parameters. Duration of CBZ use had correlation with increased ALP and duration of VPA use had correlation with decreased BMD in adult patients.

Conclusion

long term anti-epileptic drug treatment either with CBZ and VPA which has unknown effects on skeletal mineralization and induces a state of decreased bone mineral density BMD values at femoral neck were significant in CBZ group Therefore regular screening for monitoring of biochemical markers of bone turnover and BMD with DXA during the treat period is recommended. In addition, Ca supplement could be considered for all patients with epilepsy upon initiation of CBZ and VPA therapy.

Markers of bone turnover in patients with epilepsy and their relationship to management of bone diseases induced by antiepileptic drugs

Data from cross-sectional and prospective studies revealed that patients with epilepsy and on long-term treatment with antiepileptic drugs (AEDs) are at increased risk for metabolic bone diseases. Bone diseases were reported in about 50% of patients on AEDs. Low bone mineral density, osteopenia/osteoporosis, osteomalacia, rickets, altered concentration of bone turnover markers and fractures were reported with phenobarbital, phenytoin, carbamazepine, valproate, oxcarbazepine and lamotrigine. The mechanisms for AEDs-induced bone diseases are heterogeneous and include hypovitaminosis D, hypocalcemia and direct acceleration of bone loss and/or reduction of bone formation. This article reviews the evidence, predictors and mechanisms of AEDs-induced bone abnormalities and its clinical implications. For patients on AEDs, regular monitoring of bone health is recommended. Prophylactic administration of calcium and vitamin D is recommended for all patients. Treatment doses of calcium and vitamin D and even anti-resorptive drug therapy are reserved for patients at high risk of pathological fracture.

Markers of bone turnover in patients with epilepsy and their relationship to management of bone diseases induced by antiepileptic drugs

Data from cross-sectional and prospective studies revealed that patients with epilepsy and on long-term treatment with antiepileptic drugs (AEDs) are at increased risk for metabolic bone diseases. Bone diseases were reported in about 50% of patients on AEDs. Low bone mineral density, osteopenia/osteoporosis, osteomalacia, rickets, altered concentration of bone turnover markers and fractures were reported with phenobarbital, phenytoin, carbamazepine, valproate, oxcarbazepine and lamotrigine. The mechanisms for AEDs-induced bone diseases are heterogeneous and include hypovitaminosis D, hypocalcemia and direct acceleration of bone loss and/or reduction of bone formation. This article reviews the evidence, predictors and mechanisms of AEDs-induced bone abnormalities and its clinical implications. For patients on AEDs, regular monitoring of bone health is recommended. Prophylactic administration of calcium and vitamin D is recommended for all patients. Treatment doses of calcium and vitamin D and even anti-resorptive drug therapy are reserved for patients at high risk of pathological fracture.

The bone mineral content alterations in pediatric patients medicated with levetiracetam, valproic acid, and carbamazepine

AIM

The negative effect of antiepileptic drugs on bone health has been previously documented. However, which antiepileptic drug is safer in regard to bone health is still questionable. Our aims were to investigate the bone mineral density alterations in pediatric patients who receive antiepileptic medication for a minimum of two years and to compare the results of these drugs.

MATERIALS AND METHODS

Fifty-nine patients (32 males, 27 females; mean age: 8.6±4.6years) and a control group (13 males, 7 females; mean age: 7.6±3.3years) were included in the study. The patients were receiving necessarily the same antiepileptic drugs (AEDs) for at least two years, and none of the patients had mental retardation or cerebral palsy. The patients were divided into three groups: group 1 (patients receiving levetiracetam (LEV), n=20), group 2 (patients receiving carbamazepine (CBZ), n=11), and group 3 (patients receiving valproic acid (VPA), n=28). Plasma calcium (Ca), phosphorus (P), parathyroid hormone (PTH), alkaline phosphatase (ALP), vitamin D levels, and bone mineral density (BMD) values of femur and vertebras (L1-4) and z-scores (comparative results of BMD values of the patients with the age- and gender-matched controls in device database) of the groups were compared.

RESULTS

The differences between P, PTH, ALP and age, Ca and BMD results, and vitamin D levels of the patients in all four groups was not statistically significant according to Kruskal-Wallis test (p>0.05). The z-score levels of all the patient and control groups were also not statistically significantly different compared with each other.

CONCLUSION

In contrast to previous reports in pediatric patients, our study has documented that there is not a considerable bone loss in patients receiving long-term AED medication. Although levetiracetam has been proposed as bone-protecting medication, we did not observe any difference between AEDs regarding bone mineral density after two years of treatment.

Effects of antiepileptic drugs on bone mineral density and bone metabolism in children: a meta-analysis

OBJECTIVE

The aim of our meta-analysis was to assess the effects of antiepileptic drugs on bone mineral density and bone metabolism in epileptic children.

METHODS

Searches of PubMed and Web of Science were undertaken to identify studies evaluating the association between antiepileptic drugs and bone mineral density and bone metabolism.

RESULTS

A total of 22 studies with 1492 subjects were included in our research. We identified: (1) a reduction in bone mineral density at lumbar spine (standardized mean difference (SMD)=-0.30, 95% confidence interval (CI) [-0.61, -0.05]), trochanter (mean difference (MD)=-0.07, 95% CI [-0.10, -0.05]), femoral neck (MD=-0.05, 95% CI [-0.09, -0.02]), and total body bone mineral density (MD=-0.33, 95% CI [-0.51, -0.15]); (2) a reduction in 25-hydroxyvitamin D (MD=-3.37, 95% CI [-5.94, -0.80]) and an increase in serum alkaline phosphatase (SMD=0.71, 95% CI [0.38, 1.05]); (3) no significant changes in serum parathyroid hormone, calcium, or phosphorus.

CONCLUSIONS

Our meta-analysis suggests that treatment with antiepileptic drugs may be associated with decreased bone mineral density in epileptic children.

Effects of antiepileptic drugs on bone health and growth potential in children with epilepsy

BACKGROUND

Bone health may be impaired in children with epilepsy.

OBJECTIVES

Our objective was to characterize bone mineral density (BMD) and bone growth in children receiving antiepileptic drugs (AEDs) and to assess the effects of co-morbidity, vitamin D deficiency, and type of drugs used.

DATA SOURCES

Data were sourced from PubMed, Embase, and Web of Science.

ELIGIBILITY CRITERIA

Cross-sectional, cohort, case-control, or randomized controlled trials reporting BMD or parameters of bone growth.

PARTICIPANTS

Children with epilepsy compared with controls.

INTERVENTIONS

AEDS or ketogenic diet.

STUDY APPRAISAL

The studies were evaluated by one author.

SYNTHESIS METHODS

Studies were categorized as reporting reduced BMD or not at any skeletal site as outcome. A logistic regression was performed for age, percent boys, study design, type of AED, co-morbidity or not, and signs of vitamin D deficiency/osteomalacia or not.

RESULTS

Carbamazepine and valproate were analyzed as monotherapy in 11 studies, and for both drugs a limited decrease in BMD seemed present. For oxcarbazepine, levetiracetam, phenytoin, phenobarbital, and topiramate, only one study with monotherapy was found for each drug, none of which reported decreased bone density. Polytherapy with AEDs seemed to be associated with a larger decrease in bone density than was monotherapy. Although few studies were available on bone growth, these did indicate that bone growth may be impaired among users of AEDs. Ketogenic diet may be associated with decreased bone density. The main determinant of normal BMD was absence of vitamin D deficiency/osteomalacia.

LIMITATIONS

The studies differed in skeletal sites studied and most were cross-sectional. No head-to-head comparisons of AEDs were performed. Children treated with polytherapy or ketogenic diet may have more complicated and severe disease than those treated with monotherapy. The underlying cause of epilepsy and vitamin D deficiency may contribute to impaired bone growth and density.

CONCLUSIONS

Reduced bone density, impaired bone growth, and vitamin D deficiency may be seen in children treated with drugs against epilepsy.

IMPLICATIONS

Measures to correct vitamin D deficiency, calcium intake should be taken.

Longitudinal change of vitamin D status in children with epilepsy on antiepileptic drugs: prevalence and risk factors

BACKGROUND

Our aim was to evaluate the prevalence and risk factors of vitamin D deficiency and the changes of vitamin D level among children with epilepsy on antiepileptic drugs.

METHODS

The levels of serum 25-hydroxy vitamin D were measured at the start of antiepileptic drugs and at 6- to 12-month intervals in children with epilepsy taking antiepileptic drugs in Pusan National University Children's Hospital. Vitamin D deficiency was defined as 25-hydroxy vitamin D levels <20 ng/mL and insufficiency between 21 and 29 ng/mL.

RESULTS

A total of 143 children (103 boys and 40 girls) with the mean age of 7.4 ± 5.4 years were included. The mean follow-up duration was 1.8 ± 0.8 years. At the start of antiepileptic drugs and the last follow-up, vitamin D deficiency or insufficiency was recognized in 56.6% (81 of 143) and 79.0% (113 of 143), respectively (P < 0.01). The mean value of initial 25-hydroxy vitamin D was 31.1 ± 14.7 ng/mL, which was significantly decreased to 20.2 ± 14.9 ng/mL (P < 0.01) in the last follow-up. Polytherapy (-16.0 ± 13.6 ng/mL), longer duration of ≥2 years (-23.5 ± 9.1 ng/mL), tube feeding (-18.2 ± 14.5 ng/mL), and overweight with body mass index of eighty-fifth percentile or greater (-17.0 ± 12.1 ng/mL) had a significant negative effect for the longitudinal change of 25-hydroxy vitamin D. Age, etiologies, seizure outcomes, and type of antiepileptic drugs (enzyme-inducing versus nonenzyme-inducing antiepileptic drugs) did not affect the longitudinal decrease of 25-hydroxy vitamin D.

CONCLUSIONS

A high proportion of these children on antiepileptic drugs had hypovitaminosis D and a significant decrease between the initial and the last follow-up. Polytherapy and longer duration of antiepileptic drugs, tube feeding, and overweight were independently associated with longitudinally significant decrease of 25-hydroxy vitamin D.

The problem of osteoporosis in epileptic patients taking antiepileptic drugs

INTRODUCTION

Epilepsy is a common neurological disorder associated with recurrent seizures. Therapy with antiepileptic drugs (AEDs) helps achieve seizure remission in approximately 70% of epileptic patients. Treatment with AEDs is frequently lifelong and there are reports suggesting its negative influence on bone health. This is especially important in terms of general occurrence of osteoporosis, affecting over 50 million people worldwide.

AREAS COVERED

This study refers to two main groups of AEDs: hepatic enzyme inducers (carbamazepine, oxcarbazepine, phenobarbital, phenytoin, primidone and topiramate) and non-inducers (clobazam, clonazepam, ethosuximide, gabapentin, lacosamide, lamotrigine, levetiracetam, pregabalin, tiagabine, valproate, vigabatrin and zonisamide). Some reports indicate that enzyme inducers may exert a more negative influence on bone mineral density (BMD) compared to non-inducers. Bone problems may appear in both sexes during AED therapy, although women are additionally burdened with postmenopausal osteoporosis. Supplementation of vitamin D and calcium in patients on AEDs is recommended.

EXPERT OPINION

Apart from enzyme inducers, valproate (an even enzyme inhibitor) may also negatively affect BMD. However, the untoward effects of AEDs may depend upon their doses and duration of treatment. Although the problem of supplementation of vitamin D and calcium in epileptic patients on AEDs is controversial, there are recommendations to do so.

Epilepsy treatment by sacrificing vitamin D

Epilepsy is one of the most common neurologic disorders in childhood that often requires long term treatment with antiepileptic drugs. Both antiepileptic treatment and the comorbidities associated with epilepsy have a negative impact on bone health in growing children. Given the fact that vitamin D deficiency is a major public health problem worldwide, clinicians caring for children with chronic diseases should be aware of effects of the medication on the bone metabolism. Yet, vitamin D deficiency due to antiepileptic treatment is an overlooked issue among neurologists. In this review, we briefly describe vitamin D metabolism and the effect of vitamin D in the brain. We also discuss the literature in terms of vitamin D deficiency and antiepileptic treatment in the pediatric population.

The impact of the use of antiepileptic drugs on the growth of children

BACKGROUND

This study investigated whether long-term treatment with antiepileptic drugs (AEDs) had negative effects on statural growth and serum calcium levels in children with epilepsy in Taiwan.

METHODS

Children with epilepsy treated with one prescription of AEDs (monotherapy) for at least 1 year were selected. The AEDs included valproic acid (VPA; Deparkin) in 27 children (11 boys and 16 girls) aged 4-18 years, oxcarbazepine (Trileptal) in 30 children (15 boys and 15 girls) aged 5-18 years, topiramate (Topamax) in 19 children (10 boys and 9 girls) aged 6-18 years, and lamotrigine (Lamicta) in eight children (5 boys and 3 girls) aged 5-13 years. Patients with a history of febrile convulsions were selected as the controls.

RESULTS

One year of VPA treatment significantly impaired the statural growth of pediatric patients with epilepsy (p < 0.005) compared with the control group. The underlying mechanism may have been due to the direct effect of VPA on the proliferation of growth plate chondrocytes rather than alterations of serum calcium.

CONCLUSIONS

These results raise serious concerns about the growth of pediatric epilepsy patients who use AEDs, and potentially the need to closely monitor growth in children with epilepsy and adolescents under AED treatment, especially VPA.

Antiepileptic drugs and bone metabolism in children: data from 128 patients

There are conflicting results concerning bone metabolism in children receiving antiepileptic medication, with data concentrating on neurologically impaired patients. We performed a multicenter cross-sectional study in otherwise healthy children who received monotherapy with valproic acid, oxcarbazepine, lamotrigine, sulthiame, levetiracetam, or topiramate for at least 6 months. Data on calcium, phosphorus, alkaline phosphatase, 25-OH vitamin D, and parathormone were collected. Among 128 patients, 24.4% had hypocalcemia, 25.4% hypophosphatemia, and 13.3% (n = 17) 25-OH vitamin D levels <10 ng/mL. All patients were clinically asymptomatic. Mean calcium concentrations were found to be significantly lower among the study population (2.41 mmol/L) compared with healthy controls (2.53 mmol/L). Lowest mean concentration was observed in patients treated with sulthiame followed by oxcarbazepine and valproic acid. No influence of calcium intake or therapy on bone metabolism was noted. Effects on bone metabolism of anticonvulsive monotherapy are not restricted to neurologically impaired children but also affect otherwise healthy children.

Influences of bone and mineral metabolism in epilepsy

INTRODUCTION

Patients with epilepsy are at increased risk for metabolic bone disease, low bone mineral density and fractures.

AREAS COVERED

This article reviews the predictors and mechanisms of bone loss in patients with epilepsy. It provides information regarding the basic bone biology, evidences of osteopathy with epilepsy and the potential mechanisms of its pathogenesis. This review shows that long-term use of antiepileptic drugs (AEDs) is associated with the risk of osteopathy. However, age, gender, low body mass, severity of epilepsy, co-morbid conditions, institutionalization and calcium and vitamin D deficiencies are additional and modified risk factors. AEDs may indirectly accelerate bone loss through hypovitaminosis D, hypocalcemia and hyperparathyroidism or reduce bone accrual through decreasing the levels of calcitonin, growth factors and vitamin K. Also, AEDs may directly accelerate osteoclastic (bone loss) and/or reduce osteoblastic (bone formation) activities, the main cells involved in bone remodeling.

EXPERT OPINION

Understanding the basic bone biology and the pathophysiology of the disturbed bone and mineral metabolism in epilepsy will aid in identification and monitoring of patients at risk and in planning appropriate prophylactic and therapeutic measures.

Effect of carbamazepine therapy on vitamin D and parathormone in epileptic children

Evidence suggests that carbamazepine affects bone metabolism by altering vitamin D status. We prospectively compared 25-hydroxyvitamin D, parathormone, calcium, phosphorus, and alkaline phosphatase levels at initiation and 6 months of carbamazepine therapy in children, and correlated them with carbamazepine levels. We included 47 children newly diagnosed with partial epilepsy, initiated on carbamazepine therapy. Of these, 32 were studied for 6 months. Children were managed according to standard protocol. Various parameters were measured at initiation and at 6 months. Carbamazepine levels were estimated after 6 months. Mean age was 6.72 ± 2.22 years S.D. Mean 25-hydroxyvitamin D was 14.45 ± 9.77 ng/mL S.D. and 11.31 ± 9.15 ng/mL S.D. at baseline and 6 months (P = 0.023), respectively (21.7% decline). Mean parathormone increased from 34.24 ± 21.38 pg/mL S.D. to 45.01 ± 24.46 pg/mL S.D. (P = 0.001). Change in vitamin D correlated negatively with change in parathormone (r = -0.404, P = 0.022). Serum alkaline phosphatase increased from 283.50 ± 100.10 IU/L S.D. to 364.25 ± 126.98 IU/L S.D. (P < 0.001). Changes in vitamin D and parathormone did not correlate significantly with carbamazepine level. Carbamazepine therapy decreased levels of vitamin D. Hence vitamin D monitoring and supplementation may help prevent alterations in bone metabolism.

Prevalence and risk factors for vitamin D insufficiency among children with epilepsy

This cross-sectional study was designed to determine the prevalence of, and risk factors for, vitamin D insufficiency among children treated for epilepsy in a general pediatric neurology clinic. Included were 78 children with epilepsy, aged 3-17 years, treated by the authors between September 2008 and March 2009. Vitamin D levels and relevant risk factors were evaluated using multiple logistic regression. Of the 78 children, 41% were male and 81% were of European origin; the mean age was 11.64 + or - 4.37 years. 25-hydroxyvitamin D levels of <20 ng/mL were observed in 25% of the children and levels considered to be normal (>32 ng/mL) were observed in only 25%. Girls and children with elevated body mass index were at increased risk for low 25-hydroxyvitamin D. The odds ratio for low 25-hydroxyvitamin D was 4.07 for girls versus boys, with a 95% confidence interval of 1.18-13.97; for each 1-unit increase in body mass index, the odds ratio was 1.179, with a 95% confidence interval of 1.047-1.329. Use of newer antiepileptic drugs was not associated with altered risk, compared with older enzyme-inducing drugs. Vitamin D insufficiency was highly prevalent in this unselected population of children with epilepsy. Female sex and increased body mass index were significant risk factors for low vitamin D levels, but antiepileptic drug regimen was not.

Vitamin D and bone health among children with epilepsy

The lay media and scientific literature have focused increasing attention on vitamin D deficiency and insufficiency in recent years. Low vitamin D levels confer increased an risk of abnormal bone mineralization, and are linked to poor bone health in epilepsy patients. However, vitamin D is not the only determinant of bone health in children with epilepsy. Anticonvulsant medications, in addition to features and comorbidities of epilepsy and coexisting neurologic diseases, are important factors in this complex topic. We review the basic metabolism of vitamin D in terms of bone health among children with epilepsy. We also discuss the literature regarding vitamin D and bone mineral density in this population. Finally, we suggest algorithms for screening and treating vitamin D insufficiency in these patients.

Bone mineral density in children, adolescents, and young adults with epilepsy

PURPOSE

The aim of this study was to assess bone mineral density (BMD) in a large population of children, adolescents, and young adults with epilepsy alone or in association with cerebral palsy and/or mental retardation.

METHODS

Ninety-six patients were enrolled in the study. The group comprised 50 males and 46 females, aged between 3 and 25 years (mean age 11 years). The control group consisted of 63 healthy children and adolescents (23 males, 40 females), aged between 3 and 25 years (mean age 12.1 years). Patients underwent a dual-energy x-ray absorptiometry (DEXA) scan of the lumbar spine (L1-L4) and the z scores were calculated for each patient; the t score was considered for patients 18 years of age or older.

RESULTS

Abnormal BMD was found in 56 patients (58.3%), with values documenting osteopenia in 42 (75%) and osteoporosis in 14 (25%). A significant difference emerged between epileptic patients and the control group in BMD, z score, and body mass index (BMI) (p = <0.001). Lack of autonomous gait, severe mental retardation, long duration of antiepileptic treatment, topiramate adjunctive therapy, and less physical activity significantly correlated with abnormal BMD.

DISCUSSION

This study detected abnormal BMD in more than half of a large pediatric population with epilepsy with or without cerebral palsy and/or mental retardation. The clinical significance of these findings has yet to be clarified.

Evaluation of bone turnover in epileptic children using oxcarbazepine

This study evaluated the effects of oxcarbazepine monotherapy on bone turnover in prepubertal and pubertal children. Thirty-four newly diagnosed pediatric patients with normal bone mineral density, serum biochemical markers of bone formation, and hormonal markers participated. Levels of 25-hydroxyvitamin D were significantly decreased after therapy compared with baseline values. Levels of gamma-glutamyl transferase, phosphorus, alkaline phosphatase, osteocalcin, parathyroid hormone, and calcitonin had increased. However, only changes in osteocalcin and gamma-glutamyl transferase levels were statistically significant compared with baseline values. Drug-induced osteopenia was evident in 3 patients with z scores of bone-mineral density less than -2.0, whereas these patients had z scores of less than -1.5 before treatment. Although 18 months of oxcarbazepine treatment exerted slightly adverse effects on bone metabolism, the effect seems insignificant in children with normal bone-mineral density. Although alterations in bone metabolism do not always suffice to explain the decrease in bone-mineral metabolism, we think that patients with osteopenia before the initiation of oxcarbazepine therapy should be followed carefully, especially in long-term treatment.

Bone mineral density in angelman syndrome

Our aim was to evaluate bone mineral densitometry in patients with Angelman syndrome with or without antiepileptic therapy. Eighteen patients (9 females, 9 males), aged 4.0-24.3 years (mean age, 10.1 years), and two control groups consisting of 18 epileptic and 24 healthy patients, underwent dual-energy X-ray absorptiometry at the lumbar spine (L(1)-L(4)), and z score was evaluated for each patient; the t score was considered for patients aged > or = 18 years. Abnormal bone mineral density was present in 8/18 (44.5%) of patients with Angelman syndrome, in 7/18 (38.9%) of the epileptic group, and in none of the healthy controls. Furthermore, a significant difference regarding mean age of patients (6 versus 15 years, P = 0.008, by Fisher exact test), and mean length of drug treatment (3.5 versus 11.1 years, P = 0.005 by Fisher exact test), appeared in the group with Angelman syndrome. Most of these patients (94.4%) were receiving antiepileptic drugs, mainly valproic acid, for many years. In conclusion, our study revealed osteopenia in almost half the children and young patients with Angelman syndrome. Dual-energy X-ray absorptiometry should be performed in all patients with Angelman syndrome, particularly if they are treated with antiepileptic drugs.

Anti-epileptic medication and bone health

BACKGROUND

Epilepsy is a common chronic neurological disorder, usually requiring long-term treatment with anti-epileptic drugs (AED). Many studies have reported that AED therapy is associated with metabolic bone disease and is a major iatrogenic risk factor for fractures. There remains uncertainty about the type(s) of bone disease due to AED treatment, and the pathogenesis of AED-associated fractures.

RATIONALE

Deficits in bone mineral density (BMD) are widely reported in AED-treated patient populations. However, much of the research conducted to date has been limited by factors such as small sample size, potentially biased subject selection, a lack of selection of appropriate control data, and failure to take account of important confounding influences. The pathogenesis of AED-associated fractures is likely to be multifactorial, due to factors including reduced BMD, impaired bone quality (due to osteoporosis and/or osteomalacia), increased propensity to fall, and fractures associated with seizures or loss of consciousness.

RECOMMENDATIONS

Patients receiving long-term AED should be monitored for indices of bone health, including BMD and vitamin D status. Lifestyle factors should be optimized, vitamin D status maintained, and fall prevention strategies introduced as appropriate. Good seizure control is important. The use of additional, specific osteoporosis therapy is not evidence-based in this setting, but would appear reasonable in patients with clinically significant decreases in BMD, applying current treatment guidelines for osteoporosis.

CONCLUSION

There is a pressing need for improved understanding of the pathogenesis of AED-associated bone disease, for better definition of the risk associated with specific AED regimens, and for the development of evidence-based preventive and treatment approaches in this common but neglected disorder.

Antiepileptic drugs and bone metabolism

Anti-epileptic medications encompass a wide range of drugs including anticonvulsants, benzodiazepines, enzyme inducers or inhibitors, with a variety effects, including induction of cytochrome P450 and other enzyme, which may lead to catabolism of vitamin D and hypocalcemia and other effects that may significantly effect the risk for low bone mass and fractures. With the current estimates of 50 million people worldwide with epilepsy together with the rapid increase in utilization of these medications for other indications, bone disease associated with the use of anti-epileptic medications is emerging as a serious health threat for millions of people. Nevertheless, it usually goes unrecognized and untreated. In this review we discuss the pathophysiologic mechanisms of bone disease associated with anti-epileptic use, including effect of anti-epileptic agents on bone turnover and fracture risk, highlighting various strategies for prevention of bone loss and associated fractures a rapidly increasing vulnerable population.

Adverse effects of antiepileptic drugs on bone mineral density

The aim of this study is to determine the frequency of changes in biochemical markers of bone metabolism in children who are receiving valproic acid, carbamazepine, and oxcarbazepine. Thirty healthy children and 68 children with idiopathic epilepsy treated with either carbamazepine (n = 23), valproic acid (n = 31), or oxcarbazepine (n = 14) for more than 1 year were enrolled into the study. Blood samples were obtained in order to determine biochemical parameters (calcium, phosphorus, alkaline phosphates, parathormone, and 25-hydroxyvitamin D). Bone mineral density was measured with the dual-energy x-ray absorptiometry method. There were no significant differences in the serum concentrations of calcium, phosphorus, aspartate aminotransferase, alanine aminotransferase, and albumin levels between the four groups. However, serum alkaline phosphatase concentrations were higher in the patient group as compared with the control subjects. In patients receiving antiepileptic drugs, bone mineral density values were significantly lower than the healthy control group. In conclusion, long-term antiepileptic drug treatment either with valproic acid, carbamazepine, or with oxcarbazepine which has unknown effects on skeletal mineralization, induces a state of decreased bone mineral density.

Bone mineral density in subjects using central nervous system-active medications

PURPOSE

Decreased bone mineral density defines osteoporosis according to the World Health Organization and is an important predictor of future fractures. The use of several types of central nervous system-active drugs, including benzodiazepines, anticonvulsants, antidepressants, and opioids, have all been associated with increased risk of fracture. However, it is unclear whether such an increase in risk is related to an effect of bone mineral density or to other factors, such as increased risk of falls. We sought to examine the relationship between bone mineral density and the use of benzodiazepines, anticonvulsants, antidepressants, and opioids in a representative US population-based sample.

SUBJECTS AND METHODS

We analyzed data on adults aged 17 years and older from the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994). Total femoral bone mineral density of 7114 male and 7532 female participants was measured by dual-energy x-ray absorptiometry. Multivariable linear regression models were used to quantify the relation between central nervous system medication exposure and total femoral bone mineral density. Models controlled for relevant covariates, including age, sex, and body mass index.

RESULTS

In linear regression models, significantly reduced bone mineral density was found in subjects taking anticonvulsants (0.92 g/cm2; 95% confidence interval [CI]: 0.89 to 0.94) and opioids (0.92 g/cm2; 95% CI: 0.88 to 0.95) compared with nonusers (0.95 g/cm2; 95% CI: 0.95 to 0.95) after adjusting for several potential confounders. The other central nervous system-active drugs--benzodiazepines or antidepressants--were not associated with significantly reduced bone mineral density.

CONCLUSION

In cross-sectional analysis of NHANES III, anticonvulsants and opioids (but not benzodiazepines or antidepressants) were associated with significantly reduced bone mineral density. These findings have implications for fracture-prevention strategies.

Epilepsy, osteoporosis and fracture risk - a meta-analysis

This meta-analysis assesses the effects of epilepsy on fracture risk and changes in bone mineral density (BMD) in patients with epilepsy. A search of PubMed was conducted using the key words epilepsy, fracture, and bone mineral. A weighted estimate of relative risk of fractures and changes in BMD (Z-score) was calculated. From the changes in BMD, expected increase in relative fracture risk was calculated. A total of 11 studies on fracture risk and 12 studies on BMD were retrieved. The relative risk of any fracture was increased (2.2, 95% CI: 1.9-2.5, five studies), as was the risk of hip (5.3, 3.2-8.8, six studies), forearm (1.7, 1.2-2.3, six studies), and spine fractures (6.2, 2.5-15.5, three studies). A large proportion of fractures (35%) seemed related to seizures. Spine (mean +/- SEM: -0.38 +/- 0.06) and hip (-0.56 +/- 0.06) BMD Z-scores were significantly decreased, hip more than spine (2P < 0.05). The expected increases in relative risk of any fracture from BMD Z-scores were 1.2-1.3, and significantly lower than observed (2P < 0.05). The deficit in BMD in patients with epilepsy is too small to explain the observed increase in fracture risk. The remainder of the increase in fracture risk may be linked to seizures.

Bone mineral metabolism changes in epileptic children receiving valproic acid

OBJECTIVE

The aim of this study was to evaluate bone mineral density (BMD) in epileptic children receiving valproic acid (VPA) and to determine differences between osteopenic and non-osteopenic children.

METHODS

Thirty-three epileptic children, receiving VPA for at least 6 months, were compared with 33 healthy children for BMD. BMD was measured by dual-energy X-ray absorptiometry at lumbar vertebrae, femoral neck and greater trochanter. Serum calcium, phosphorus, alkaline phosphates, osteocalcin and VPA levels were also determined.

RESULTS

Patient's osteocalcin levels were significantly higher (P = 0.02) and femur and trochanter BMD values were significantly lower (P = 0.04 and P = 0.03, respectively). Duration of VPA therapy was significantly longer and doses of VPA were significantly higher in seven osteopenic patients compared with 26 non-osteopenic patients. Osteopenic patients (4.6 +/- 2.4 years) were younger than non-osteopenic patients (7.8 +/- 3.2 years) (P = 0.01).

CONCLUSION

Long-term and high dose VPA therapy may cause osteopenia, primarily in younger epileptic children. These patients should be followed closely by BMD measurements.

Antiepileptic drugs and reduced bone mineral density

There is a growing interest in recognizing the association between antiepileptic drugs and reduced bone mineral density. Although the literature regarding this association has been available for more than three decades, the management of this complication remains unclear. We review the relevant literature regarding antiepileptic drugs and reduction in bone mineral density with the aim of developing some guidelines for practical management of this problem. This review focuses on the mechanism of antiepileptic drug-induced bone loss, its recognition, and its management.

Bone health in pediatric epilepsy

Childhood and adolescence are critical periods of skeletal mineralization. Peak bone mineral density achieved by the end of adolescence determines the risk for later pathological fractures and osteoporosis. Chronic disease and medication often adversely affect bone health. Epilepsy is one of the most common neurological conditions occurring in persons under the age of 21. Epilepsy may affect bone in a number of ways. Restrictions of physical activity imposed by seizures; limitations on physical activity resulting from cerebral palsy, frequently present in patients with symptomatic epilepsy; and medications used to treat seizures can all adversely affect bone health. It has long been observed that treatment with phenytoin and phenobarbital can be associated with rickets. More recently, established agents such as carbamazepine and valproate have been shown to be associated with a lowering of bone mineral density. The literature related to bone health in pediatric epilepsy is reviewed, although it should be noted that these data are limited.

Bone mineral status in ambulatory pediatric patients on long-term anti-epileptic drug therapy

BACKGROUND

For ambulatory pediatric outpatients,reports of abnormalities of bone metabolism associated with anti-epileptic drugs are inconsistent and may be difficult to interpret.

METHODS

The effects of long-term anti-epileptic therapy (mainly valproic acid and/or carbamazepine) on bone mineral status were evaluated in ambulatory epileptic patients(seven males and 11 females) aged 5.5-15.9 years. Bone mineral density (BMD) at the lumbar spine was measured by dual-energy X-ray absorptiometry and markers of bone and mineral metabolism were determined.

RESULTS

The mean BMD was decreased by 9% in our patients relative to the control, and five patients (all males)showed osteopenia, defined as BMD SD scores less than - 1.5. Serum levels of minerals, intact parathyroid hormone and 1alpha,25(OH)2 vitamin D were within the normal ranges. In most patients, serum levels of intact osteocalcin, carboxyterminal propeptide of type I procollagen and pyridinoline cross-linked telopeptide of type I collagen were reduced relative to the corresponding mean control values. The BB genotype by BsmI restriction fragment length polymorphism, associated with low BMD, was not found in our patients. The dietary calcium intake in the osteopenic patients was significantly lower than that of the non-osteopenic patients.

CONCLUSIONS

Our results indicate that long-term anti-epileptic treatment induces a state of decreased bone turnover in children, resulting in osteopenia preferentially in males. The alterations may be due, at least in part, to direct effects of the drugs on bone cells; and that low calcium intake could be an aggravating factor for anti-epileptic-associated osteopenia.