The effect of levetiracetam on rat bone mass, structure and metabolism

Effects of levetiracetam on bone mineral density and bone metabolism in patients with epilepsy: A systematic review and meta-analysis

PURPOSE

The effects of levetiracetam (LEV) on bone mineral density (BMD) and bone metabolism are currently inconclusive, and this study was designed to answer this question.

METHODS

Citations from PubMed, Embase, Cochrane Library, and Web of Science databases (up to February 4, 2024) were reviewed. The effects of LEV on BMD as well as bone metabolism indicators were measured by calculating the standardized mean difference (SMD) with a 95% confidence interval (CI). This study was registered with PROSPERO (CRD42024509560).

RESULTS

A total of 612 individuals from 13 studies were included in the present analysis. Of the items related to bone metabolism, LEV was found to be associated significantly with decreased serum calcium with an SMD of -0.47 (95 % CI, -0.77- -0.16; p = 0.04). However, changes in other markers (including serum phosphorus, 25-hydroxyvitamin D, alkaline phosphatase, and parathyroid hormone) were not statistically significantly correlated with the use of LEV (p > 0.05). Also, when compared to the control groups, the changes in BMD of the observation groups were not significant (p > 0.05).

CONCLUSIONS

The use of LEV may significantly reduce serum calcium in patients with epilepsy, and regular monitoring of bone metabolism-related indicators is recommended.

The impact of antiseizure medication on bone heath: A systematic review of animal studies

BACKGROUND

Antiseizure medications (ASMs) are known to potentially impact bone health, but existing literature presents conflicting results regarding their specific effects on bone mineralization, metabolism, and quality.

OBJECTIVE

This systematic review aims to establish a consensus regarding the influence of ASMs on bone health based on existing preclinical studies.

METHODS

Following SYRCLE and PRISMA guidelines, we conducted a systematic search in PubMed, Science Direct, and Google Scholar to identify relevant studies. Ultimately, 21 articles were selected for inclusion in this review.

RESULTS

Among the chosen studies, approximately half involved Wistar rats as experimental subjects. Levetiracetam and sodium valproate were the most frequently investigated drugs, with a typical treatment duration of 10-12 weeks. These studies exhibited a low risk of bias in aspects like sequence generation, random housing, random outcome assessment, and reporting bias. However, blinding in performance, allocation concealment, and detection were often rated as having a high risk of bias. The collective findings suggest that prolonged ASM use leads to reduced bone mineral density, altered bone turnover marker levels (including hypovitaminosis D, hypocalcemia, and secondary hyperparathyroidism), deterioration of bone microarchitecture, and decreased mechanical strength.

CONCLUSION

The adverse effects on bone associated with ASMs are not limited to enzyme-inducing drugs, as newer generation ASMs may also contribute to these effects. Hypovitaminosis D alone may not be solely responsible for ASM-induced bone issues, suggesting the involvement of other mechanisms. Furthermore, substantial variations were observed in the results of different preclinical studies on individual ASMs, highlighting the need to standardize animal study methodologies to enhance reproducibility and reduce variation.

Assessment of the toxic effects of levetiracetam on biochemical, functional, and redox parameters of salivary glands in male Wistar rats

Levetiracetam (LEV) is an anticonvulsant for epilepsy. The toxic effects of this medication in tissues have been associated with redox state imbalance, which can lead to salivary gland dysfunction. Therefore, the current work investigated the effects of LEV on the biochemical, functional, and redox parameters of the parotid and submandibular glands in rats. For this, male Wistar rats (Rattus norvegicus albinus) were randomly divided into 3 groups (n = 10/group): Control (0.9% saline solution), LEV100 (100 mg/kg), and LEV300 (300 mg/kg). After 21 consecutive days of intragastric gavage treatments, pilocarpine stimulated saliva secretion was collected for salivary biochemical analysis. The extracted salivary glands were utilized for histomorphometry and redox state analyses. Our results showed that LEV300 increased plasma hepatotoxicity markers and reduced salivary amylase activity and the acinar surface area of the parotid gland. Total oxidant capacity and oxidative damage to lipids and proteins were higher in the parotid gland, while total antioxidant capacity and uric acid levels were reduced in the submandibular gland of the LEV100 group compared to Control. On the other hand, total oxidant capacity, oxidative damage to lipids and proteins, total antioxidant capacity, and uric acid levels were lower in both salivary glands of the LEV300 group compared to Control. Superoxide dismutase and glutathione peroxidase activities were lower in the salivary glands of treated animals compared to Control. In conclusion our data suggest that treatment with LEV represents a potentially toxic agent, that contributes to drug-induced salivary gland dysfunction.

An insight into the implications of estrogen deficiency and transforming growth factor β in antiepileptic drugs-induced bone loss

There have been a number of reports that chronic antiepileptic drug (AEDs) therapy is associated with abnormal bone and calcium metabolism, osteoporosis/osteomalacia, and increased risk of fractures. Bony adverse effects of long term antiepileptic drug therapy have been reported for more than four decades but the exact molecular mechanism is still lacking. Several mechanisms have been proposed regarding AEDs induced bone loss; Hypovitaminosis D, hyperparathyroidism, estrogen deficiency, calcitonin deficiency. Transforming growth factor-β (TGF- β) is abundant in bone matrix and has been shown to regulate the activity of osteoblasts and osteoclasts in vitro. All isoforms of TGF- β are expressed in bone and intricately play role in bone homeostasis by modulating estrogen level. Ovariectomised animal have shown down regulation of TGF- β in bone that could also be a probable target of AEDs therapy associated bone loss. One of the widely accepted hypotheses regarding the conventional drugs induced bone loss is hypovitaminosis D which is by virtue of their microsomal enzyme inducing effect. However, despite of the lack of enzyme inducing effect of certain newer antiepileptic drugs, reduced bone mineral density with these drugs have also been reported. Thus an understanding of bone biology, pathophysiology of AEDs induced bone loss at molecular level can aid in the better management of bone loss in patients on chronic AEDs therapy. This review focuses mainly on certain new molecular targets of AEDs induced bone loss.

Antiepileptic Stiripentol May Influence Bones

Bone structure abnormalities are increasingly observed in patients chronically treated with antiepileptic drugs (AEDs). The majority of the available data concern older conventional AEDs, while the amount of information regarding newer AEDs, including stiripentol, is limited. The aim of the study was to assess the effect of stiripentol on bones. For 24 weeks, male Wistar rats, received 0.9% sodium chloride (control group) or stiripentol (200 mg/kg/day) (STP group). In the 16th week of the study, we detected lower serum PINP levels in the STP group compared to the control group. In the 24th week, a statistically significant lower 1,25-dihydroxyvitamin D3 level, higher inorganic phosphate level and higher neutrophil gelatinase-associated lipocalin (NGAL) levels in serum were found in the STP group compared to the control. Micro X-ray computed tomography of the tibias demonstrated lower bone volume fraction, lower trabecular thickness, higher trabecular pattern factor and a higher structure model index in the stiripentol group. Considering the results of this experiment on rats which suggests that long-term administration of stiripentol may impair the cancellous bone microarchitecture, further prospective human studies seem to be justified. However, monitoring plasma vitamin D, calcium, inorganic phosphate and kidney function in patients on long-term stiripentol therapy may be suggested.

Effects of long-term antiepileptic polytherapy on bone biochemical markers in ambulatory children and adolescents and possible benefits of vitamin D supplementation: a prospective interventional study

PURPOSE

Our aim was to investigate any adverse effects of long-term polytherapy (VPA and add-on-therapy) on bone biochemical markers in ambulatory children and adolescents with epilepsy and the possible benefits of vitamin D supplementation on the same markers.

METHODS

In this prospective interventional study, the levels of 25(OH)D and the bone turnover markers of CrossLaps (CTX), total alkaline phosphatase (tALP), osteoprotegerin (OPG), and the receptor activator for nuclear factor kB (RANK) ligand (sRANKL) were determined in forty-two ambulatory children with epilepsy on polytherapy (valproic acid + one or more other from levetiracetam, topiramate, lamotrigine, or rufinamide). The same markers were assessed after a year's supplementation of vitamin D (400 IU/d) and were compared with those of clinically healthy controls. The respective mean (±SD) ages were 11.9 ± 4.6 and 11.4 ± 4.4 yrs.

RESULTS

The basal mean 25(OH)D levels in the patients did not differ from controls (23.9 ± 11.5 vs 27.4 ± 13.3 ng/ml), but increased significantly after the vitamin D intake (31.1 ± 13.3 ng/ml, p < 0.01). In parallel, basal serum CTX levels were found to be significantly lower in the patients than controls (0.89 ± 0.63 vs 1.22 ± 0.58 ng/ml, p < 0.02), but not tALP. Osteoprotegerin was higher in the patients (5.7 ± 7.7 pmol/L vs 2.6 ± 1.0 pmol/L, p < 0.03), while sRANKL did not differ. After vitamin D, the CTX levels increased to comparable levels in controls (0.99 ± 0.57 ng/ml), and those of OPG decreased to levels that did not differ from controls (4.9 ± 5.1 pmol/L). The ratio of OPG/sRANKL was higher in patients than controls before treatment (0.030 ± 0.045 vs 0.009 ± 0.005, p < 0.03), but decreased (0.026 ± 0.038) to comparable values in controls later.

CONCLUSIONS

These findings imply a lower bone turnover in the young patients on long-term polytherapy (VPA and add-on-therapy), but after one year's vitamin D intake, bone biochemical markers improved.

Effects of valproate, lamotrigine, and levetiracetam monotherapy on bone health in newly diagnosed adult patients with epilepsy

PURPOSE

The aim of this study was to evaluate the effects of valproate (VPA), lamotrigine (LTG), and levetiracetam (LEV) on bone turnover and bone mineral density (BMD) in newly diagnosed adult patients with epilepsy.

METHODS

Eligible adult patients who were newly diagnosed with epilepsy were treated with VPA, LTG, and LEV. The chemical indicators of bone metabolism and BMD were measured before treatment and 2 years after treatment with different antiseizure medication (ASM) monotherapies. Then, the differences in these parameters before and after treatment were analyzed.

RESULTS

One hundred twenty-four patients completed the 2 years follow-up; 43 received monotherapy with VPA, 32 received LTG, and 49 received LEV. Serum parathyroid hormone (PTH), bone alkaline phosphatase (B-ALP), and β-cross-linked C-telopeptide of type I collagen (β-CTX) levels were elevated in adult patients after 2 years of VPA administration; the serum procollagen I intact N-terminal peptide (PINP) level was noticeably higher in patients after LEV treatment than before treatment. Meanwhile, the BMD of the lumbar spine and femoral neck did not change in patients treated with VPA, LTG, and LEV.

CONCLUSIONS

Valproate altered bone turnover in adult patients with epilepsy, while LTG and LEV did not exert harmful effects on bone health in adult patients.

A Review of Molecular Imaging of Glutamate Receptors

Molecular imaging with positron emission tomography (PET) and single photon emission computed tomography (SPECT) is a well-established and important in vivo technique to evaluate fundamental biological processes and unravel the role of neurotransmitter receptors in various neuropsychiatric disorders. Specific ligands are available for PET/SPECT studies of dopamine, serotonin, and opiate receptors, but corresponding development of radiotracers for receptors of glutamate, the main excitatory neurotransmitter in mammalian brain, has lagged behind. This state of affairs has persisted despite the central importance of glutamate neurotransmission in brain physiology and in disorders such as stroke, epilepsy, schizophrenia, and neurodegenerative diseases. Recent years have seen extensive efforts to develop useful ligands for molecular imaging of subtypes of the ionotropic (N-methyl-D-aspartate (NMDA), kainate, and AMPA/quisqualate receptors) and metabotropic glutamate receptors (types I, II, and III mGluRs). We now review the state of development of radioligands for glutamate receptor imaging, placing main emphasis on the suitability of available ligands for reliable in vivo applications. We give a brief account of the radiosynthetic approach for selected molecules. In general, with the exception of ligands for the GluN2B subunit of NMDA receptors, there has been little success in developing radiotracers for imaging ionotropic glutamate receptors; failure of ligands for the PCP/MK801 binding site in vivo doubtless relates their dependence on the open, unblocked state of the ion channel. Many AMPA and kainite receptor ligands with good binding properties in vitro have failed to give measurable specific binding in the living brain. This may reflect the challenge of developing brain-penetrating ligands for amino acid receptors, compounded by conformational differences in vivo. The situation is better with respect to mGluR imaging, particularly for the mGluR5 subtype. Several successful PET ligands serve for investigations of mGluRs in conditions such as schizophrenia, depression, substance abuse and aging. Considering the centrality and diversity of glutamatergic signaling in brain function, we have relatively few selective and sensitive tools for molecular imaging of ionotropic and metabotropic glutamate receptors. Further radiopharmaceutical research targeting specific subtypes and subunits of the glutamate receptors may yet open up new investigational vistas with broad applications in basic and clinical research.

Antiepileptic Drugs and Bone Health: Current Concepts

Chronic use of antiepileptic drugs (AEDs) can induce the development of adverse effects on bone metabolism. In epileptic patients treated with AED, the monitoring of biochemical markers of bone turnover, such as the measurement of serum 25 (OH) vitamin D, bone mineral density, before the beginning of the treatment and during the follow-up is not routinely required. In the future, monitoring of biochemical markers in epileptic patients treated with AED may help us for adequate prevention therapy.

The effect of gabapentin and pregabalin on bone turnover and bone strength: A prospective study in Wistar rats

BACKGROUND

There are limited data on the effects of GBP on bone and no data for PGB. Some data suggest that there is a significant influence of sex hormone balance on the susceptibility of bone to antiepileptic drug-induced bone loss.

METHODS

Forty-eight male Wistar rats were divided into six groups that were subjected to two surgeries, sham (noORX) or real orchidectomy (ORX), and were fed three diets, a SLD, a SLD enriched with GBP or a SLD enriched with PGB. Dual energy X-ray absorptiometry was used to measure the bone mineral density. The concentrations of bone turnover markers were assayed. The femurs were biomechanically tested.

RESULTS

Significant reductions in bone mineral density, weight and biomechanical strength were observed in ORX animals. GBP or PGB exposure did not cause significant alterations in bone mineral density or biomechanical strength. No changes in bone turnover markers were observed, except for RANKL. A significant increase was found in the ORX GBP and ORX PGB groups. Within the orchidectomized animal group, RANKL levels were significantly higher in the ORX PGB group than in the ORX GBP group.

CONCLUSIONS

Because neither GBP nor PGB affected bone mineral density or mechanical bone strength, both of these antiepileptic drugs could be considered drugs with lower risks to bone health. A shift in RANKL levels indicates that the effects of GBP and PGB on osteoclast activity may be dependent on the hormonal status of animals.

An explorative literature review of the multifactorial causes of osteoporosis in epilepsy

PURPOSE

Patients with epilepsy have a greatly increased risk of osteoporosis and fractures. The literature is diverse and contradictory when dealing with the underlying pathophysiological mechanisms. Consequently, the purpose of this review was to shed light on the multifactorial causes behind the increased occurrence of metabolic bone disease in patients with epilepsy and to identify areas for future research.

METHODS

A review of the literature was performed searching PubMed with relevant Medical Subject Headings MeSH terms. The results of the search were evaluated for relevance to the review based on the title and abstract of the publication. Publications in language other than English and publications pertaining only pediatric patients were excluded. For all studies, included reference lists were evaluated for further relevant publications. In total, 96 publications were included in this explorative review.

RESULTS

The high occurrence of metabolic bone disease in patients with epilepsy is multifactorial. The causes are the socioeconomic consequences of having a chronic neurological disease but also adverse effects to antiepileptic drug treatment ranging from interference with calcium and vitamin D metabolism to hyponatremia-induced osteoporosis.

CONCLUSION

The literature supports the need for awareness of bone health in patients with epilepsy. The pathophysiological mechanisms are many and various wanting for further research in the less well-characterized areas. Furthermore, great responsibility rests on the healthcare professionals in implementing comprehensive patient care and in assuring bone protective measures in clinical practice to prevent bone loss in patients with epilepsy.

An update on the problem of osteoporosis in people with epilepsy taking antiepileptic drugs

INTRODUCTION

Antiepileptic drugs (AEDs) have been associated with a negative impact on bone health. Comorbid disorders in patients with epilepsy may require drugs exerting a pro-osteoporotic effect, so a possibility of untoward interactions with AEDs is probable.

AREAS COVERED

This review discusses evidence related to the deteriorating influence of AEDs on bone, demonstrating generally stronger negative effects of conventional AEDs. Lamotrigine seems to be a safer AED in this regard. Further, literature data indicate that generally AEDs can lower the serum concentration of vitamin D. Importantly, pediatric patients are of greater risk of bone problems during therapy with AEDs, which is probably due to their effects on bone-forming processes.

EXPERT OPINION

Supplementation with vitamin D and calcium is frequently recommended in patients taking AEDs chronically. Whether to add a bisphosphonate remains an open question due to the limited data on this issue. A possibility of negative interactions exists between AEDs and other pro-osteoporotic drugs: glucocorticoids, proton pump inhibitors and aromatase inhibitors. Depression is a frequent comorbidity in patients with epilepsy. Clinical data indicate that antidepressant drugs may also increase the risk of fractures. Again, patients with epilepsy and depression may be exposed to a greater risk of osteoporosis.

Levetiracetam and lamotrigine effects as mono- and polytherapy on bone mineral density in epileptic patients

OBJECTIVE

The purpose of this study was to determine the effect of lamotrigine (LTG) and levetiracetam (LEV) as mono- and polytherapy on biochemical markers of bone turnover and bone mineral density in Egyptian adult patients with epilepsy.

METHODS

Forty-eight patients were divided into four groups: two received monotherapy of either LTG or LEV, and the other two groups received polytherapy comprising (valproate [VPA] + LTG or VPA + LEV). Thirty matched healthy participants were included in the study. Participants completed a nutritional and physical activity questionnaire. Biochemical markers of bone and mineral metabolism and bone mineral density of the lumbar spine were measured at baseline and at six months.

RESULTS

In the LEV monotherapy group, the bone formation markers showed a significant decrease in serum alkaline phosphatase and serum osteocalcin levels while the bone resorption marker showed a significant increase in urinary deoxypyridinoline levels. After six months of treatment, bone mineral density showed a significant decrease in all treated groups, while among monotherapy groups, this significant decrease was more prevalent in the LEV monotherapy group compared with the LTG monotherapy group. Furthermore, there was significant negative correlation between urinary deoxypyridinoline levels and bone mineral density in the LEV monotherapy group.

CONCLUSION

Using new generation antiepileptics, LEV monotherapies and polytherapy showed harmful effects on bone but LTG did not.

The anti-epileptic drugs valproate, carbamazepine and levetiracetam cause bone loss and modulate Wnt inhibitors in normal and ovariectomised rats

Secondary osteoporosis is the major concern associated with long term intake of antiepileptic drugs (AEDs). Women are the vulnerable targets owing to post-menopausal bone loss. In the present work, we evaluated the effect of 10 weeks of treatment with AED therapy (carbamazepine, CBZ, 75 mg/kg; sodium valproate, SVP, 300 mg/kg; levetiracetam, LTM, 150 mg/kg) on bone mineral density and microarchitecture at femoral epiphysis, lumbar vertebrae and proximal tibia of normal and ovariectomised Wistar rats. In addition, we measured serum levels of vitamin D, receptor activator of nuclear factor kappa β-ligand (RANKL), procollagen type 1 amino-terminal propeptide (P1NP) and wnt inhibitors (sclerostin and DKK-1) following AED therapy. Micro-computed tomography analysis of bones revealed significant reduction in BMD at femur epiphysis and lumbar vertebrae with all the three AEDs evaluated. At proximal tibia, only CBZ showed a significant decline. The reduction in BMD was more pronounced in ovariectomised rats. AEDs also resulted in alteration of micro-CT parameters. These changes were accompanied by an increased serum RANKL with all AEDs while vitamin D levels were reduced only with CBZ treatment and P1NP levels were reduced with SVP and CBZ. Serum sclerostin levels were elevated following all AEDs in normal and ovariectomised rats except with CBZ in normal rats. However, increase in DKK-1 levels was observed with only LTM. Ovariectomy itself resulted in increased RANKL, sclerostin and DKK-1 and reduced vitamin D and P1NP levels. Significant differences were discernible between normal and ovariectomised rats treated with AEDs in all the parameters. However, while sclerostin increased further upon AEDs treatment, P1NP decreased with SVP and CBZ and serum DKK-1 levels showed a declining trend with all the three AEDs studied. We confirm adverse effects on bone following AEDs in female rats. Further, our results demonstrate for the first time that these effects are more pronounced in ovariectomised rats as compared to normal rats and that this could be related to estrogen deficiency which in turn enhances bone resorption via increased RANKL and reduces bone formation via increased sclerostin and reduced P1NP. Finally, our study demonstrated for the first time that AED treatment displayed changes in the serum levels of wnt inhibitors and hence modulation of wnt inhibitors might be partly involved in their adverse effects on bone.

Impact of antiepileptic drugs on bone health: Need for monitoring, treatment, and prevention strategies

Epilepsy is the most common neurological disorder affecting approximately 50 million people worldwide. In India, overall prevalence of epilepsy is reported to be 5.59/1000 population. Antiepileptic drugs (AEDs) constitute the main-stay of treatment with a large number of AEDs available in the market. High incidence of adverse effects is a major limitation with AEDs. One of the major concerns is significant metabolic effects on the bone. However, little attention has been paid to this issue because most of the bone effects remain subclinical for a long time and may take years to manifest clinically. The main effects include hypocalcemia, hypophosphatemia, reduced serum levels of Vitamin D, increase in parathormone (PTH) levels, and alterations in bone turnover markers. The CYP450 enzyme-inducing AEDs such as phenytoin, phenobarbital, carbamazepine, and primidone are the most common AEDs associated with bone disorders while the data regarding the effect of valproate and newer AEDs such as lamotrigine, gabapentin, vigabatrin, levetiracetam, and topiramate on bone metabolism and bone density are scanty and controversial. Deficiency of Vitamin D is commonly described as a cause for the bone loss in epileptic patients while others being decreased absorption of calcium, increased PTH levels, and inhibition of calcitonin secretion, etc. However, there are no formal practical guidelines for the management of bone disease among those taking AEDs. Evidence-based strategies regarding monitoring, prevention, and treatment of bone diseases in patients on AED therapy are needed.

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.

Phenytoin and sodium valproate but not levetiracetam induce bone alterations in female mice

Adverse effects on the bone are amongst the potentially adverse clinical consequences with antiepileptic drugs (AEDs). This study compared the effects of 3 AEDs (phenytoin (PHT), sodium valproate (SVP), and levetiracetam (LTM)) on the bones of a Swiss strain of albino female mice. Drugs were administered daily for 4 months at doses that produced plasma concentrations corresponding to the clinically relevant therapeutic ranges. PHT and SVP (but not LTM) significantly lowered the bone mineral density (BMD) of lumbar vertebrae (L2–L4) as evaluated by dual-energy X-ray absorptiometry (DEXA) scan. The findings were supported by histopathology of vertebral (lumbar) bone and analysis of bone turnover markers. While both PHT and SVP reduced alkaline phosphatase (ALP) and hydroxyproline (HxP) in lumbar vertebrae, and elevated tartarate-resistant acid phosphatase (TRAP) and urinary excretion of calcium, LTM did not affect any of these markers of bone turnover, indicating that the drug might be a safer option in female epileptic patients prone to bone changes.

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.