Antiepileptic drugs and high prevalence of low bone mineral density in a group of inpatients with chronic epilepsy

Hormonal Changes in Women with Epilepsy

Epilepsy is a prevalent neurological disorder among women globally, often requiring long-term treatment. Hormonal fluctuations in women with epilepsy (WWE) can have reciprocal effects on epilepsy and antiseizure medications (ASMs), posing significant challenges for WWE. Notably, WWE commonly experience endocrine alterations such as thyroid dysfunctions, low bone metabolism, and reproductive hormone irregularities. On the one hand, the presence of hormones in women with epilepsy affects their susceptibility to epilepsy as well as the metabolism of antiseizure medications in various ways. On the other hand, epilepsy itself and the use of antiseizure medications impact the production, secretion, and metabolism of hormones, resulting in low fertility, increased risk of pregnancy complications, negative offspring outcomes, and so on. In order to develop more precise treatment strategies in the future, it is necessary to comprehend the explicit relationships between hormones, epilepsy, and antiseizure medications, as well as to elucidate the currently known mechanisms underlying these interactions.

Impaired bone health as a co-morbidity of epilepsy

Increasing number of studies shows significant reductions in bone mineral density in patients with epilepsy treated with enzyme-inducing anti-seizure medications (EIASM), valproic acid, and newer anti-seizure medications (ASM). ASM seems to be a specific risk factor for the development of osteoporosis affecting 11%-31% of patients with epilepsy and leads to 2 to 6 times increased risk of fractures compared to the background population. Treatment with ASM clearly contributes to epilepsy-associated bone disease. Yet, the exact pathophysiological mechanism has not been established; however, several hypotheses were suggested, especially in relation to EIASM. As the long-lasting medical treatment, often in polytherapy, has shown negative effects on bone health, it indicates the need for guidelines for the prevention and management of bone disease to be included in the follow-up of patients with epilepsy. An algorithm for following bone status during the treatment has been suggested based on Danish national guidelines.

How Do Drugs Affect the Skeleton? Implications for Forensic Anthropology

Simple Summary

Forensic anthropologists analyze human remains to assist in the identification of the deceased, predominantly by assessing age-at-death, sex, stature, ancestry and any unique identifying features. Whilst methods have been established to create this biological profile of the skeleton, these may be influenced by a number of factors. This paper, for the first time, provides an overview from a reading of the clinical and pharmacological literature to explore whether the intake of drugs can affect the skeleton and whether these may have implications for forensic anthropology casework. In effect, drugs such as tobacco, heroin, and prescription medications can alter bone mineral density, can increase the risk of fractures, destroy bone and changes to the dentition. By considering how drugs can affect the skeleton, forensic anthropologists can be aware of this when attempting to identify the deceased.

Abstract

Forensic anthropologists rely on a number of parameters when analyzing human skeletal remains to assist in the identification of the deceased, predominantly age-at-death, sex, stature, ancestry or population affinity, and any unique identifying features. During the examination of human remains, it is important to be aware that the skeletal features considered when applying anthropological methods may be influenced and modified by a number of factors, and particular to this article, prescription drugs (including medical and non-medical use) and other commonly used drugs. In view of this, this paper aims to review the medical, clinical and pharmacological literature to enable an assessment of those drug groups that as side effects have the potential to have an adverse effect on the skeleton, and explore whether or not they can influence the estimation of age-at-death, sex and other indicators of the biological profile. Moreover, it may be that the observation of certain alterations or inconsistencies in the skeleton may relate to the use of drugs or medication, and this in turn may help narrow down the list of missing persons to which a set of human remains could belong. The information gathered from the clinical and medical literature has been extracted with a forensic anthropological perspective and provides an awareness on how several drugs, such as opioids, cocaine, corticosteroids, non-steroidal anti-inflammatory drugs, alcohol, tobacco and others have notable effects on bone. Through different mechanisms, drugs can alter bone mineral density, causing osteopenia, osteoporosis, increase the risk of fractures, osteonecrosis, and oral changes. Not much has been written on the influence of drugs on the skeleton from the forensic anthropological practitioner perspective; and this review, in spite of its limitations and the requirement of further research, aims to investigate the current knowledge of the possible effects of both prescription and recreational drugs on bones, contributing to providing a better awareness in forensic anthropological practice and assisting in the identification process of the deceased.

Associations between osteoporosis and drug exposure: A post-marketing study of the World Health Organization pharmacovigilance database (VigiBase®)

BACKGROUND

Bone remodeling is a complex process, and many conditions (including drug exposure) lead to osteoporosis. Here, we sought to detect new disproportionality signals for drugs associated with osteoporosis.

METHODS

We performed a disproportionality analysis of the World Health Organization's VigiBase® pharmacovigilance database through April 12, 2020. The frequency of reports on osteoporosis for all identified drug classes was compared with that for all other drugs and quoted as the reporting odds ratio (ROR) [95% confidence interval (CI)].

RESULTS

Of the 7,594,968 cases spontaneously recorded to VigiBase®, 4758 concerned osteoporosis. New disproportionality signals with a pharmacologically plausible mechanism were found for drugs used in neurology (levodopa (ROR [95%CI]: 10.18 [4.33-25.10]), selective serotonin agonists (4.22 [2.34-7.00]) and memantine (4.10 [1.56-8.93])), hematology (romiplostim (4.93 [1.15-21.10])), pulmonology (macitentan (3.02 [1.84-4.90])), ophthalmology (ranibizumab (3.31 [1.00-10.51])) and rheumatology (tofacitinib (3.65 [3.00-4.40])). The robustness of these new results is supported by the significant RORs for the vast majority of drugs already known to induce osteoporosis and/or increase the fracture risk, namely glucocorticoids, gonadotropin-releasing hormone analogs, anti-aromatases, androgen receptor blockers, thyroid hormones, proton pump inhibitors, thiazolidinediones, vitamin K antagonists, loop diuretics, protease inhibitors, nucleoside and nucleotide reverse transcriptase inhibitors, and enzyme-inducing antiepileptics including barbiturates and derivatives, hydantoin derivatives, carboxamide derivatives and fatty acid derivatives.

CONCLUSION

We established up a comprehensive list of drugs potentially associated with osteoporosis and highlighted those with pharmacologically plausible mechanisms leading to bone fragility. Our results might pave the way for additional exploration of these mechanisms.

Bone mineral density and fractures in institutionalised children with epilepsy and intellectual disability

BACKGROUND

Long-term use of antiseizure drugs is associated with a low bone mineral density (BMD) and an increased fracture risk. The literature regarding institutionalised children on chronic antiseizure drugs is limited. Therefore, the aim of this cross-sectional study is to evaluate the prevalence of low BMD and the history of fractures in institutionalised children with epilepsy and intellectual disability (ID).

METHODS

A dual-energy X-ray absorptiometry of lumbar spine (L1-L4) and hip was performed in 24 children, residing in a long-stay care facility in the Netherlands. Additionally, serum concentrations of albumin, calcium and 25-hydroxyvitamin D were determined. Data on fractures were retrospectively extracted from the medical files.

RESULTS

Ages of the children (14 male and 10 female) ranged from 5 to 17 years with a mean age of 13.0 (±3.2). The criteria of the International Society for Clinical Densitometry (ISCD) were used for classification of bone mineral disorders. Eight (33.3%) children had a normal BMD (Z-score > - 2.0). Of the 16 children with a low BMD (Z-score ≤ - 2.0), three were diagnosed as osteoporotic, based on their fracture history. Ten children (41.7%) were reported to have at least one fracture in their medical history. Serum concentrations of albumin-corrected calcium (2.28-2.50 mmol/L) and (supplemented) vitamin D (16-137 nmol/L) were within the normal range.

CONCLUSIONS

This study demonstrated that 67% of institutionalised children with epilepsy and ID had low BMD and 42% had a history of at least one fracture, despite supplementation of calcium and vitamin D in accordance with the Dutch guidelines.

High prevalence of vertebral fractures in seizure patients with normal bone density receiving chronic anti-epileptic drugs

People with epilepsy who take certain medications are at risk for developing osteoporosis and fractures of the vertebrae that commonly go undiagnosed. By using technology available in a bone density scan, we observed at least one fracture in many subjects with bone density in the normal and osteopenic range.

PURPOSE/INTRODUCTION

Chronic use of antiepileptic drugs (AEDs), both enzyme-inducing (phenytoin, phenobarbital, carbamazepine, and primidone) and non-enzyme-inducing (i.e., valproate), is recognized as a cause of secondary osteoporosis. Vertebral compression fractures (VF) are the most common type of osteoporotic fractures and may confer an increased risk of future hip, wrist, and vertebral fractures. Vertebral compression fractures in the general population are frequently asymptomatic, and under-diagnosed. The purpose of this study is to describe the prevalence of VF in a cohort of male veterans with epilepsy on chronic AEDs.

METHODS

The cohort for this study consisted of 146 male veterans who carried a diagnosis of epilepsy and were chronic users of AEDs known to cause osteoporosis (phenobarbital, phenytoin, carbamazepine, primidone, and valproate). Chronic AED use was defined as receiving an AED for at least 2 years. Subjects were previously seen in the osteoporosis clinic and had been evaluated by a dual-energy X-Ray absormetry (DXA) instrument including morphometric studies following a standard vertebral fracture assessment (VFA) protocol during the same DXA imaging acquisition session.

RESULTS

The mean age was 63 years. Low bone mineral density defined as osteoporosis or osteopenia was observed in 29% and 43% respectively. We observed at least one VF in 41 % of the subjects who had normal BMD, 54% in the osteopenic range, and 75% in the osteoporotic range.

CONCLUSIONS

By performing a VFA in addition to standard bone densitometric studies, we disclosed a large prevalence of compression fractures in individuals with epilepsy chronically treated with AEDs who had BMDs in the normal and osteopenic ranges. The addition of VFA or other imaging methods to evaluate VF should be included in the evaluation of bone health in individuals with epilepsy receiving AEDs since it may modify treatment recommendations to prevent future osteoporotic fractures.

Incidence of clinical fractures: A 7-year follow-up study in institutionalized adults with epilepsy and intellectual disability

PURPOSE

To determine the incidence of clinical fractures over seven years of follow-up, in adults with epilepsy and intellectual disability, residing in a long-stay care facility.

METHODS

In 2009, all institutionalized adult patients (n = 261) were invited to undergo a Dual-energy X-ray Absorptiometry (DXA) measurement and a Vertebral Fracture Assessment (VFA). Participants were followed over seven years or until date of discharge (in case of moving from the care facility) or date of death. The patients' medical files were screened for radiology reports and staff notes, to identify clinical fractures. Fracture incidence rates (IR) were determined and compared for subgroups, by calculating incidence rate ratios. Hazard ratios were calculated to identify factors associated with fracture risk, using Cox Proportional Hazards analyses.

RESULTS

A total of 205 patients (124 male, 60.5%) aged between 18 and 88 years (median 48, IQR 34-60) were enrolled. At baseline, 92 patients (44.9%) were diagnosed with osteopenia and 65 (31.7%) with osteoporosis. Between 2009 and 2016, 30 patients (14.6%) deceased and 3 patients (1.5%) left the care facility. During follow-up, 156 clinical fractures were reported in 82 patients (40.0%). Thirty-eight patients (18.5%) had at least one major osteoporotic fracture. Overall, the IR was 11.6 fractures per 100 person-years. Fracture risk was significantly lower in patients who were wheelchair dependent than in patients who were able to walk (p<.001).

CONCLUSION

This study demonstrated that 40% of institutionalized adults with epilepsy and intellectual disability had at least one clinical fracture during seven years of follow-up, despite adequate anti-osteoporosis treatment.

Management of lower extremity orthopaedic injuries in epileptic patients: A systematic review

Lower-extremity injuries may occur during seizures. There is a lack of standardized guidelines when diagnosing and planning perioperative care. Databases were systematically screened using predefined search terms. Of the 13 patients included, seven (53.8%) involved bilateral femoral neck fractures. Associated fractures were observed in all cases with surgical intervention performed in eight (61.5%) patients. Eleven patients reported functional outcomes, with over a quarter (three of 11, [27.3%]) endorsing mild range of motion deficits or issues with ambulation. Post-seizure patients may require standardized diagnostic protocols to ensure prompt management with a specialized treatment approach that accommodates the nuances of their condition.

[Inpatient treatment costs, cost-driving factors and potential reimbursement problems due to epileptic seizure-related injuries and fractures]

BACKGROUND

The systematic analysis of disease-specific costs is becoming increasingly more relevant in an economically oriented healthcare system. Chronic diseases are of particular interest due to the long duration as well as frequent hospitalization and physician visits. Epilepsy is a frequent neurological disorder affecting all age groups with the clinical hallmark of paroxysmal epileptic seizures, which are often associated with injuries.

OBJECTIVE

The aim of this work was to process the inpatient treatment costs due to seizure-related injuries and fractures. Moreover, relevant cost-causing factors were addressed. Using an alternative calculation of the costs of care, the question of potential reimbursement problems in the current German diagnosis-related groups (G-DRG) system was additionally assessed.

METHODS

For this monocentric retrospective analysis the actual proceeds of 62 inpatients who were treated at the University Hospital Frankfurt between January 2010 and January 2018 for injuries and fractures due to epileptic seizures were used. The analysis of potential cost-causing factors was carried out with respect to relevant sociodemographic and clinical aspects. The alternative calculation of the costs of treatment was carried out using established health economic methods.

RESULTS

The average DRG revenue was 7408€ (±8993€, median 5086€, range 563-44,519€), the average calculated costs were 9423€ (±11,113€, 5626€, range 587-49,830€). A length of stay ≥7 days (p = 0.014) was identified as a significant cost-driving factor. Due to the significant difference (p < 0.001) between revenue and calculated costs, an analysis was made according to factors for potential reimbursement problems, which remained significant for a length of stay of ≥7 days (p = 0.014) and for treatment in the intensive care unit (p = 0.019).

CONCLUSION

The inpatient treatment costs for patients with injuries and fractures due to epileptic seizures are high and therefore relevant from a health economic perspective. In general, reimbursement according to the G‑DRG appears to cover the actual costs, but there may be reimbursement problems for patients with a long period of hospitalization or a stay in an intensive care ward.

Effectiveness of osteoporosis medication on site-specific fracture-risk attenuation among adults with epilepsy

OBJECTIVE

The objective of this propensity score-matched, observational cohort study was to determine the effectiveness of osteoporosis medication on reducing the risk of non-trauma fracture (NTFx) among adults with epilepsy.

METHODS

Data from 01/01/2012 to 09/30/2015 was extracted from Optum Clinformatics Data Mart. NTFx risk attenuation from 12 months prior to 12 months after the individual's index date was examined for each group of adults ≥50 years of age as risk ratios (RRs with 95% confidence intervals [CIs]). Groups were stratified based on: (1) epilepsy status, as with vs without epilepsy (EP); and (2) if and when osteoporosis medication was first prescribed, as new users (treatment naive), consistent users (osteoporosis medication prescribed in pre-index period), and no users. Comparison groups were matched 1:1 to EP new users (n = 828/group) for demographics, glucocorticoid and antiseizure medication, and the Elixhauser comorbidity index. Difference-in-difference analysis compared the change in pre- to post-index NTFx risk among groups as the ratio of the RR (RRR).

RESULTS

The pre- to post-index NTFx risk at any site was reduced for EP new users (RR = 0.49; 95% CI = 0.40-0.61) and EP consistent users (RR = 0.70; 95% CI = 0.38-0.98), but nonsignificantly elevated for EP no users (RR = 1.39; 95% CI = 0.93-2.07)-findings were consistent for most sites (eg, vertebral column). EP new users had a larger NTFx risk attenuation at any site compared to EP no users (RRR = 0.35; 95% CI = 0.23-0.54) and EP consistent users (RRR = 0.70; 95% CI = 0.51-0.97). EP consistent users had a larger NTFx risk attenuation at any site compared to EP no users (RRR = 0.50; 95% CI = 0.32-0.79). The extent of NTFx risk attenuation at any site was similar for new users with vs without epilepsy (RRR = 0.99; 95% CI = 0.73-1.34) and consistent users with vs without epilepsy (RRR = 0.81; 95% CI = 0.55-1.17). There was evidence of site-specific effects (eg, hip).

CONCLUSION

Osteoporosis medication is associated with a clinically meaningful 12-month NTFx risk attenuation for adults with epilepsy, especially for those just starting osteoporosis medication.

Prevalence and incidence of vertebral fractures: a 7-year follow-up study in institutionalized adults with refractory epilepsy and intellectual disability

OBJECTIVE

The main objective of this cohort study is to determine the prevalence and incidence of morphometric vertebral fractures (VFs) over 7 years follow-up, in institutionalized adults with refractory epilepsy and intellectual disability (ID).

METHODS

Dual-energy X-ray Absorptiometry (DXA) and Vertebral Fracture Assessment (VFA) were performed in 2009 and 2016. Vertebrae T4-L4 were assessed using quantitative morphometry. Severity of VFs was graded as 1 (mild; 20-25% reduction in height), 2 (moderate; 25-40% reduction) or 3 (severe; >40% reduction) according to the method described by Genant. Prevalent VFs were analyzed at baseline. VFs (grade 1, 2 or 3) present at follow-up, but not at baseline, were considered new VFs. Worsening VFs were defined as VFs with at least one grade deterioration at follow-up, compared to baseline (grade 1 to 2 or 3, or grade 2 to 3). Patients were treated with anti-osteoporosis treatment according to the Dutch guideline.

RESULTS

Baseline and follow-up DXA and VFA could be obtained in 141 patients (87 male) aged between 18-79 years old (mean 44.8 ± 15.7). At baseline, 56 patients had at least one prevalent VF. Patients with a prevalent VF were significantly older than patients without (49.2 ± 13.7 vs 41.9 ± 16.4, p < .01). After 7 years follow-up, 38 new VFs occurred in 27 patients and 15 patients had a worsening VF, leading to an overall cumulative incidence of 27.0%. VF incidence was significantly higher in patients with at least one prevalent VF at baseline (48.2% vs 12.9%, respectively, p < .01) compared to no VF.

SIGNIFICANCE

In adults with refractory epilepsy VFA is challenging, due to physical and behavioral aspects, resulting in a substantial proportion of unevaluable vertebrae and scans. Nevertheless, 40% of the patients had a VF at baseline and after 7 years follow-up, 27% had at least one new and/or worsening VF despite adequate anti-osteoporosis treatment.

The effect of normalization of sodium on bone turnover markers in patients with epilepsy. A randomized single-blinded placebo-controlled trial

Hyponatremia [p[Na]<136 mmol/L] is an independent risk factor for decreased bone mineral density (BMD). However, whether hyponatremia represents a surrogate marker, or a direct causal relationship to bone loss remains unknown. The aim of the study was to investigate the effect of salt replacement therapy on bone turnover markers (BTM) and BMD in patients with epilepsy and chronic hyponatremia. This prospective single-blinded randomized trial investigated serum BTM and BMD, evaluated by Dual Energy X-ray Absorptiometry (DXA), in 21 patients at baseline and following three months of salt replacement therapy. Patients with two consecutive measurements of hyponatremia prior to baseline and no known osteoporosis were included from the epilepsy out-patient clinic at Rigshospitalet, Denmark. Seven patients were randomized to placebo and 14 to salt intervention. The baseline p[Na] was 134 (130.5–140) mmol/L (median (IQR)). All patients had BTM within age-specific reference ranges at baseline. Following 3 months of intervention with 3–9 g of salt daily there was no difference in levels of procollagen type 1 N-terminal propeptide (P1NP) or C-terminal cross-linking telopeptide of type 1 collagen (CTX) between placebo and intervention. Nor was there any difference in BMD evaluated at the lumbar spine (L₁-L₄) or at the femoral neck or total hip. In our study, salt replacement did neither affect BTM nor BMD. However, due to the small size of the study, more studies are needed to further investigate this.

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Patients with epilepsy and hyponatremia have low bone turnover.

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Defining chronic hyponatremia in patients with epilepsy is challenging.

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Bone turnover markers are not affected by salt supplements.

Vitamin D status among patients with drug-resistant and non-drug-resistant epilepsy

Background & Aims: Epilepsy affects nearly 70 million people worldwide. Vitamin D deficiency may influence the balance of certain epilepsies. The purpose of this study was to determine the vitamin D status and anthropometric measurements of people with epilepsy (PWE), according to their pharmacosensitivity. Methods: Forty-six PWE, with or without drug resistance, underwent nutritional assessment after giving consent. Weight, body mass index (BMI), triceps skinfold thickness (TSF), fat mass (FM) and free fat mass (FFM) by bioelectrical impedance analysis were measured. Serum vitamin D was determined without supplementation. Deficiency was defined as a level < 30 ng/mL. Statistical analysis involved Student t test, ANOVA and Chi². Results: Patients were aged 44.5 ± 14.3 years, with 60.9% of drug-resistance. BMI was 28.7 ± 7.0, 2.2% were malnourished and 30.4% obese according to the BMI. The average vitamin D level was 15.3 ± 9.9 ng/mL, with 87.0% of deficiency, and 40.0% of severe deficiency (<10 ng/mL). The TSF was higher in drug-resistant cases (p = 0.03). There was no link between drug resistance and anthropometric measurements, FM, FFM or vitamin D concentration. Conclusions: Although limited in size, this study showed that PWE are more often obese. Vitamin D deficiency is more common than in the general population, with a much higher prevalence of severe deficiency.

The mortality burden attributable to nontrauma fracture for privately insured adults with epilepsy

OBJECTIVE

Individuals with epilepsy have poor bone development and preservation throughout the lifespan and are vulnerable to nontrauma fracture (NTFx) and post-NTFx complications. However, no studies have examined the contribution of NTFx to mortality among adults with epilepsy. The objective was to determine whether NTFx is a risk factor for mortality among adults with epilepsy.

METHODS

Data from 2011 to 2016 were obtained from Optum Clinformatics Data Mart, a nationwide claims database from a single private payer in the United States. Diagnosis codes were used to identify adults (≥18 years old) with epilepsy, NTFx, and covariates (demographics and pre-NTFx cardiovascular disease, respiratory disease, diabetes, chronic kidney disease, cancer). Crude mortality rate per 100 person-years was estimated. Cox regression estimated hazard ratios (HRs) and 95% confidence intervals (CIs) were determined for mortality, comparing epilepsy and NTFx (EP + NTFx; n = 11 471), epilepsy without NTFx (EP without NTFx; n = 50 384), without epilepsy and with NTFx (without EP + NTFx; n = 423 041), and without epilepsy and without NTFx (without EP without NTFx; n = 6.8 million) after adjusting for covariates.

RESULTS

The 3-, 6-, and 12-month crude mortality rates were highest among EP + NTFx (12-month mortality rate = 8.79), followed by without EP + NTFx (12-month mortality rate = 4.80), EP without NTFx (12-month mortality rate = 3.06), and without EP without NTFx (12-month mortality rate = 0.47). After adjustments, the mortality rate was elevated for EP + NTFx for all time points compared to EP without NTFx (eg, 12-month HR = 1.70, 95% CI = 1.58-1.85), without EP + NTFx (eg, 12-month HR = 1.41, 95% CI = 1.32-1.51), and without EP without NTFx (eg, 12-month HR = 5.23, 95% CI = 4.88-5.60). Stratified analyses showed higher adjusted HRs of 12-month mortality for EP + NTFx for all NTFx sites (ie, vertebral column, hip, extremities), all age categories (young, middle-aged, older), and for both women and men.

SIGNIFICANCE

Among adults with epilepsy and compared to adults without epilepsy, NTFx is associated with a higher 12-month mortality rate. Findings suggest that NTFx may be a robust risk factor for mortality among adults with epilepsy.

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.

Hyponatremia and metabolic bone disease in patients with epilepsy: A cross-sectional study

AIM

Patients with epilepsy frequently develop hyponatremia due to the treatment with antiepileptic drugs and have an increased risk of developing metabolic bone disease. Hyponatremia is known to be associated with osteoporosis. The aim of the study was to investigate the association between hyponatremia and osteoporosis in patients with epilepsy.

METHOD AND MATERIAL

This cross-sectional study included patients with epilepsy from a tertiary epilepsy out-patient clinic in Denmark, who had a Dual Energy X-ray Absorptiometry scan performed and an accompanying plasma sodium (p-Na) measured prior to or a maximum of 14 days after the scan. Information regarding the patients' health and medical conditions were obtained from their medical reports.

RESULTS

A total of 695 patients (females 53.8%, age 49 (34:63) years (median (quartiles)) were included. 10.4% had hyponatremia (p-Na ≤ 135 mmol/L). The hyponatremic patients had significantly lower T-scores in the lumbar spine, femoral neck and total femur (all p < 0.023) and the odds ratio of osteoporosis (T-score < -2.5) was significantly increased (2.91 (1.61-5.27) (95% confidence interval) (p = 0.001)). When adjusting for potential confounders the patients with moderate and severe hyponatremia (p-Na < 129 mmol/L) had a significantly lower mean T-score in the lumbar spine (p = 0.030).

CONCLUSION

We conclude that hyponatremia is common in patients with epilepsy and that moderate and severe hyponatremia is independently associated with decreased bone mineral density in the lumbar spine. Therefore, hyponatremia in a patient with epilepsy should warrant further examination of the patient for bone loss and osteoporosis.

Effect of Long-term Carbamazepine Therapy on Bone Health

Introduction:

Recent research reported that prolonged use of AET is associated with changes in bone metabolism, with consequent reduction in bone mineral density (BMD) and increased risk of fractures.

Objectives:

Therefore, the aim of our study was to investigate the effects of carbamazepine on serum levels of 25 -hydroxyvitamin D and on biomarker of bone formation and resorption (serum levels of osteocalcin).

Material and methods:

We measured serum levels of 25-OHD and osteocalcin (OCLN) in normal controls (n=30) and in epilepsy patients taking carbamazepine (CBZ) (n=50) in monotherapy for a period of at least twelve months. For each participant, mineral density (BMD) was evaluated by dual-energy X-ray absorptiometry method.

Results:

The average value of vitamin D in serum was significantly lower in CBZ group than in control group (Vit D 17.03+12.86 vs. 32.03+6.99, p=0.0001). The average value of osteocalcin in serum was significantly higher in CBZ group than in control group (26.06+10.78 vs. 19.64+6, 54, p=0.004).BMD value in CBZ group was significantly lower than in control group (T. score CBZ: 0.08+1.38 vs. T. score control: 0.73+ 1.13, p=0.031; Z score CBZ:-0.05+1.17 vs. Z. score control: 0.55+0.79, p=0.015).

Conclusion:

AEDs are associated with bone disease, as evidenced by biochemical abnormalities and decreased BMD. Patients on long-term antiepileptic therapy, especially with enzyme-inducing agents, could benefit of routine measurement of biochemical markers of bone turnover, and BMD measurement as part of osteoporosis investigation.

Carbamazepine adverse drug reactions

INTRODUCTION

Carbamazepine (CBZ) is used for the treatment of epilepsy and other neurological and psychiatric disorders. The occurrence of adverse reactions (ADRs) to CBZ can negatively impact the quality of life of patients, as well as increase health-care costs. Thus, knowledge of CBZ-induced ADRs is important to achieve safer treatment outcomes. Areas covered: This review describes the clinical features, known mechanisms, and clinical management of the main CBZ-induced ADRs. In addition, pharmacogenetic studies focused on ADRs induced by CBZ are cited. Expert commentary: CBZ-induced ADRs are well known in the literature. The metabolite CBZ-10,11-epoxide plays an important role in the mechanism that underlies the ADRs induced by CBZ. Several factors should be considered for a safer use of CBZ, such as monotherapy prescription when possible, an adequate dose titration, knowledge of previous ADRs in the patient, and routine monitoring of CBZ plasma concentrations in symptomatic patients. Pharmacogenetics is a potential tool for CBZ therapy improvement, and the design of multicenter studies focused on the identification of biomarkers for CBZ-induced ADRs could provide useful information for a safer CBZ therapy.

Bone impairment assessed by HR-pQCT in juvenile-onset systemic lupus erythematosus

High-resolution peripheral quantitative computed tomography (HR-pQCT) analysis of female juvenile-onset systemic lupus erythematosus (JoSLE) patients revealed trabecular/cortical bone damage and reduced bone strength primarily at the distal radius compared to healthy controls. We demonstrated for the first time that JoSLE patients with vertebral fracture (VF) present trabecular impairment at the distal radius.

INTRODUCTION

This study investigated the volumetric bone mineral density (vBMD), microarchitecture, and biomechanical features at the distal radius and tibia using HR-pQCT and laboratory bone markers in JoSLE patients compared to controls to determine whether this method discriminates JoSLE patients with or without VF.

METHODS

We compared 56 female JoSLE patients to age- and Tanner-matched healthy controls. HR-pQCT was performed at the distal radius and tibia. Serum levels of the amino-terminal pro-peptide of type I collagen, the C-terminal telopeptide of type I collagen, intact parathormone, sclerostin, and 25-hydroxyvitamin D (25OHD) were evaluated. VFs were analyzed using VFA-dual-energy X-ray absorptiometry (DXA) (Genant's method).

RESULTS

Reduced density and strength parameters and microarchitecture alterations of cortical and trabecular bones were observed in JoSLE patients compared to controls, primarily at the distal radius (p < 0.05). Patients with VF exhibited a significant decrease in trabecular bone parameters solely at the distal radius (Total.BMD, p = 0.034; Trabecular.BMD [Tb.BMD], p = 0.034; bone volume (BV)/trabecular volume (TV), p = 0.034; apparent modulus, p = 0.039) and higher scores for disease damage (Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACR-DI), p = 0.002). Bone metabolism markers were similar in all groups. Logistic regression analysis of parameters that were significant in univariate analysis revealed that Tb.BMD (OR 0.98, 95 % CI 0.95-0.99, p = 0.039) and SLICC/ACR-DI (OR 7.37, 95 % CI 1.75-30.97, p = 0.006) were independent risk factors for VF.

CONCLUSION

In conclusion, this study is the first demonstration of bone microstructure and strength deficits in JoSLE patients, particularly at the distal radius. Our results demonstrated that VF was associated with trabecular radius alteration and emphasized the potential detrimental effect of disease damage on this condition.

Osteoporosis Associated with Epilepsy and the Use of Anti-Epileptics-a Review

The increased rate of fractures associated with epilepsy has been long recognised but remains incompletely understood. Study quality and study results have varied, with some but not all studies showing bone diseases including osteoporosis and/or osteomalacia, and a high prevalence of vitamin D insufficiency and deficiency are also noted. Falls risk can also be higher in patients with epilepsy taking anti-epileptic medications, potentially leading to fracture. Larger research collaborations are recommended to further advance understanding in this field, particularly to examine underlying genetic and pharmacogenomic associations of epilepsy and anti-epileptic medication usage and its association with bone diseases and fractures, as well as further investigation into optimal management of bone health in epilepsy.

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.

Musculoskeletal manifestations of Fabry disease: A retrospective study

OBJECTIVES

Fabry disease is a rare X-linked metabolic disorder characterized by a deficiency in the enzyme alpha-galactosidase A. Both males and females can be affected. The main presenting symptom is pain in the extremities, whereas at a more advanced stage, the manifestations include hypertrophic cardiomyopathy, cardiac dysrhythmia, proteinuria, chronic kidney dysfunction, stroke, and hearing loss. When not diagnosed and treated, Fabry disease causes early death. No studies specifically designed to describe the musculoskeletal manifestations of Fabry disease are available.

METHODS

We conducted a single-center retrospective study of patients receiving follow-up at a Fabry disease referral center. We described the musculoskeletal manifestations and analyzed the differential diagnoses.

RESULTS

Our study included 40 patients belonging to 20 families, including 25 females with a mean age of 44.2 years (range, 20-76 years) and 15 males with a mean age of 40.1 years (range, 16-61 years). Mean age at the diagnosis of Fabry disease was 37.2 years (range, 7-71 years) in the females and 26.9 years (range, 9-51 years) in the males. Specific enzyme replacement therapy was given to 10 (40%) females and 12 (80%) males. Musculoskeletal manifestations were as follows: past or present pain in the extremities (13 females and 10 males), combined in some patients with vasomotor disorders in the extremities and telangiectasia; exercise intolerance (12 females and 12 males); osteoporotic fractures (2 brothers aged 45 and 44 years, respectively); osteoporosis (3 females, aged 57, 63, and 75 years, respectively), which contributed to death in the oldest patient; osteopenia (2 females aged 38 and 47 years, respectively; and 1 male aged 43 years); Charcot foot and lymphedema with serious infectious complications (4 males older than 40 years), with avascular osteonecrosis of the lower limbs in 2 cases; toe amputations (3 cases); bilateral lower-limb amputation (1 case); abnormally slender lower limbs (5 females and 8 males); acute gout (3 males with severe chronic kidney failure); and carpal tunnel syndrome (1 female and 1 male, both younger than 40 years). Mistaken diagnoses that were made at an early stage, contributing to delay the identification of Fabry disease, included rheumatic fever (2 females and 2 males), growing pains (2 males), pain with paralysis (1 female), chilblains of the lower limbs (1 female), and erythermalgia (1 female). In adulthood, the following mistaken diagnoses were made: Sjögren's syndrome and/or sicca syndrome (6 females), systemic sclerosis (1 male), dysautonomia (1 female), and familial Mediterranean fever (1 female).

CONCLUSION

The diagnosis of Fabry disease is usually delayed, due to confusion with more common disorders. Musculoskeletal manifestations may constitute the presenting symptoms. Past or present pain in the extremities is typical. Osteoporosis may develop early and become severe. Together with the family history, the presence of musculoskeletal manifestations can lead to the correct diagnosis by prompting alpha-galactosidase assays in males and genetic testing in females. Fabry disease is often responsible for musculoskeletal manifestations, of which the most common are pain in the extremities and osteoporosis. These manifestations can be inaugural and lead to diagnostic wanderings. They require specific treatment strategies.

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.