Bone status in patients with epilepsy: relationship to markers of bone remodeling

[Bone mineral density assessment of women on long-term antiepileptic therapy]

OBJECTIVE

To study the effect of anticonvulsants on bone mineral density in patients with epilepsy.

MATERIAL AND METHODS

The study included 90 women with epilepsy and a control group of 60 healthy women. The subjects' serum levels of parathyroid hormone, alkaline phosphatase, calcium, phosphorus, and vitamin D were measured. Mineral density and bone structure were assessed using dual-energy X-ray absorptiometry (DEXA).

RESULTS

In women with epilepsy, the serum levels of calcium, phosphorus, and vitamin D were significantly lower compared to the control group, and the levels of parathyroid hormone and alkaline phosphatase were significantly higher. There was also a statistically significant difference in the DEXA values between study groups. In women with epilepsy who received enzyme-inducing antiepileptic drugs, calcium, phosphorus, and vitamin D levels were significantly lower compared to patients who received enzyme-inhibiting antiepileptic drugs. Bone mineral density was positively correlated with serum micronutrients (calcium, phosphorus, vitamin D) and negatively with serum alkaline phosphatase and duration of therapy.

CONCLUSION

Bone tissue disorders are common in patients with epilepsy. These disorders may be associated with prolonged use of antiepileptic drugs, especially enzyme inducers.

Phenytoin is associated with increased risk of osteoporosis and fragility fractures in adult epileptic patients

INTRODUCTION

Osteoporotic fractures lead to significant decreases in the quality of life with increases in morbidity, mortality, and disability. Treatment with a variety of anti-epileptic drugs, such as phenytoin, has been understood to cause a decrease in bone mineral density.

MATERIALS AND METHODS

Cohort A was identified as patients that were 18-55 years old that had epilepsy and recurrent seizures that were also prescribed phenytoin. Cohort B was identified as patients that were 18-55 years old that had epilepsy and recurrent seizures but were not prescribed phenytoin or other anti-epileptic medications. Cohorts were matched for relevant confounding pathologies and demographic factors. Outcomes were evaluated from 1 day to 5 years after the indexed event.

RESULTS

A total of 35,936 patients with epilepsy that were prescribed phenytoin were matched with 109,335 patients with epilepsy that were not prescribed phenytoin. Patients on phenytoin therapy were at significantly higher risk for osteoporosis without pathological fracture, fracture of metatarsal bone, fracture of shoulder and upper arm, fracture of distal radius, fracture of thoracic vertebra, fracture of cervical vertebra, fracture of lumbar vertebra, fracture of femoral head or neck, pertrochanteric fracture, femoral shaft fracture, and distal tibia fracture (all outcomes p < 0.001).

CONCLUSION

Epileptic patients on phenytoin therapy that were 18-55 years old exhibited higher associated risk of osteoporosis and osteoporotic-fragility fractures of various regions. Patients that undergo phenytoin therapy for epilepsy treatment should be educated on the increased risk of bone fractures and have appropriate lifestyle and diet modifications.

The Effect of Chronic Swimming Exercise and Vitamin E Supplementation on Bone Element Metabolism in Epileptic Rats

INTRODUCTION

This study aimed to investigate the effects of chronic swimming exercise and vitamin E administration on elemental levels in the bone tissue of epileptic rats.

METHODS

Forty-eight rats were divided into six groups: Control, Swimming, Swimming + vitamin E, Swimming + Epilepsy, Swimming + Epilepsy + vitamin E, and Epilepsy. Vitamin E was administered to the animals chronically by gavage at a dose of 500 mg/kg every other day for 3 months. Epileptiform activity was induced with penicillin in animals 24 hours after the last vitamin E intake. The exercise program consisted of daily 30-minute swimming sessions. At the end of the treatment period, the levels of calcium, chromium, copper, iron, magnesium, manganese, lead, and zinc (µg/gram tissue) in bone tissue samples were measured using an atomic emission device.

RESULTS

The results showed that all epileptic groups had significantly lower bone chromium levels compared to the control groups (p<0.05). The epileptic, and epileptic swimming groups had the lowest levels of bone calcium, magnesium, and zinc (p<0.05). Vitamin E administration resulted in a significant increase in bone calcium, magnesium, and zinc levels in the epileptic swimming group with vitamin E compared to the epileptic and epileptic swimming groups. (p<0.05).

CONCLUSION

The findings of the study show that the administration of vitamin E improves calcium, magnesium, and zinc metabolism in the deteriorated bone tissue of the epileptic rat model.

The association of osteoprotegerin and RANKL with osteoporosis: a systematic review with meta-analysis

OBJECTIVES

The OPG/RANKL signal pathway was important regulation mechanism of bone remodeling cycle, but the effect of osteoprotegerin (OPG) and RANKL in osteoporosis was uncertain. We did a systematic review with meta-analysis to assess the association between serum OPG/RANKL and osteoporosis.

METHODS

The systematic search, data extraction, critical appraisal, and meta-analysis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Randomized controlled studies were searched in PubMed, OvidMedline, Embase (1946 to present). Standard mean difference (SMD), and associated credible interval (CI) were calculated using RevMan statistical software to assess the continuous data. Heterogeneity in studies was measured by I2 values. Subgroup analysis was performed based on different bone turnover.

RESULTS

A total of 5 randomized controlled studies met the inclusion criteria. Both OPG and RANKL had no significant differences between the osteoporosis and control group, and the statistical heterogeneity was high in meta-analysis. However, RANKL had significant differences between the osteoporosis group with low bone turnover and control group (SMD =  - 1.17; 95% CI - 1.77 to 0.57; P value < 0.01) in subanalysis. Furthermore, the OPG/RANKL ratio was significant lower in the osteoporosis group than in the control group (SMD =  - 0.29; 95% CI - 0.57 to - 0.02; P value < 0.05), and the statistical heterogeneity was very low (Chi2 = 0.20, P = 0.66, I2 = 0%).

CONCLUSIONS

Our meta-analysis study supported OPG and RANKL were important modulatory factors of bone formation and resorption in bone turnover, respectively. Although the serum level of both OPG and RANKL were not associated with osteoporosis, but the OPG/RANKL ratio was associated with osteoporosis. In future, standardizing the test method and unit was good to clinical application.

Development and validation of a machine learning-derived radiomics model for diagnosis of osteoporosis and osteopenia using quantitative computed tomography

Background

To develop and validate a quantitative computed tomography (QCT) based radiomics model for discriminating osteoporosis and osteopenia.

Methods

A total of 635 patients underwent QCT were retrospectively included from November 2016 to November 2019. The patients with osteopenia or osteoporosis (N = 590) were divided into a training cohort (N = 414) and a test cohort (N = 176). Radiomics features were extracted from the QCT images of the third lumbar vertebra. Minimum redundancy and maximum relevance and least absolute shrinkage and selection operator were used for data dimensional reduction, features selection and radiomics model building. Multivariable logistic regression was applied to construct the combined clinical-radiomic model that incorporated radiomics signatures and clinical characteristics. The performance of the combined clinical-radiomic model was evaluated by the area under the curve of receiver operator characteristic curve (ROC–AUC), accuracy, specificity, sensitivity, positive predictive value, and negative predictive value.

Results

The patients with osteopenia or osteoporosis were randomly divided into training and test cohort with a ratio of 7:3. Six more predictive radiomics signatures, age, alkaline phosphatase and homocysteine were selected to construct the combined clinical-radiomic model for diagnosis of osteoporosis and osteopenia. The AUC of the combined clinical-radiomic model was 0.96 (95% confidence interval (CI), 0.95 to 0.98) in the training cohort and 0.96 (95% CI 0.92 to 1.00) in the test cohort, which were superior to the clinical model alone (training-AUC = 0.81, test-AUC = 0.79). The calibration curve demonstrated that the radiomics nomogram had good agreement between prediction and observation and decision curve analysis confirmed clinically useful.

Conclusions

The combined clinical-radiomic model that incorporates the radiomics score and clinical risk factors, can serve as a reliable and powerful tool for discriminating osteoporosis and osteopenia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12880-022-00868-5.

Differential effects of antiepileptic drugs on human bone cells

Antiepileptic drugs (AED) have been associated to in vivo deleterious consequences in bone tissue. The present work aimed to characterize the cellular and molecular effects of five different AED on human osteoclastogenesis and osteblastogenesis. It was observed that the different drugs had the ability to differentially modulate both processes, in a way dependent on the identity and dose of the AED. Shortly, valproic acid stimulated either osteoclastogenesis and osteoblastogenesis, whereas carbamazepine, gabapentin, and lamotrigine revealed an opposite behavior; topiramate elicited a decrease of osteoclast development and an increase in osteoblast differentiation. This is the first report describing the direct effects of different AED on human primary bone cells, which is a very important issue, because these drugs are usually consumed in long-term therapeutics, with acknowledged in vivo effects in bone tissue.

A Cross-Sectional Study to Assess the Modulation of Wnt Inhibitors following Anti-Epileptic Drug Therapy and their Correlation with Vitamin D and Receptor Activator of Nuclear Factor κ B Ligand in Indian Women with Epilepsy

Long-term anti-epileptic drug (AED) therapy compromises bone health. Although vitamin D deficiency is proposed to be involved, it alone is not held responsible. This accounts for investigating other mechanisms in bone accrual. Recent studies have shown modulation of inhibitors of wnt pathway, sclerostin and dickkopf-1 (DKK-1), in glucocorticoids-induced osteoporosis. We investigated whether AED monotherapy modulates wnt inhibitors in Indian women with epilepsy. Women of age > 20-40 years with the diagnosis of epilepsy and receiving AEDs (carbamazepine, valproate and levetiracetam) for at least a year were enrolled. The results were compared with age-matched healthy controls with no evidence of metabolic bone disease. Women undergoing treatment with AEDs (mean duration: 50.59 ± 37.929 months) exhibited higher serum sclerostin and receptor activator of nuclear factor κ B ligand (RANKL) and lower vitamin D (25-hydroxy vitamin D) and DKK-1 levels when compared to age-matched healthy controls. Sclerostin showed a positive correlation with RANKL, while DKK-1 presented no such relationship. However, no association was evident after adjusting for age, duration of treatment and total daily dose. Although a correlation between wnt inhibitors and RANKL could not be obtained, AEDs displayed changes in serum levels of wnt inhibitors in persons with epilepsy and hence these drugs may compromise bone health through a disturbance in wnt signalling mechanisms.

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.

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.

Long-term warfarin therapy and biomarkers for osteoporosis and atherosclerosis

Background

Stroke prevention by warfarin, a vitamin K antagonist, has been an integral part in the management of atrial fibrillation. Vitamin K-dependent matrix Gla protein (MGP) has been known as a potent inhibitor of arterial calcification and osteoporosis. Therefore, we hypothesized that warfarin therapy affects bone mineral metabolism, vascular calcification, and vascular endothelial dysfunction.

Methods

We studied 42 atrial fibrillation patients at high-risk for atherosclerosis having one or more coronary risk factors. Twenty-four patients had been treated with warfarin for at least 12 months (WF group), and 18 patients without warfarin (non-WF group). Bone alkaline phosphatase (BAP) and under carboxylated osteocalcin (ucOC) and receptor activator of nuclear factor-kappa B ligand (RANKL) were measured as bone metabolism markers. Reactive hyperemia-peripheral arterial tonometry (RH-PAT) index measured by Endo-PAT2000 was used as an indicator of vascular endothelial function.

Results

There were no significant differences in patient background characteristics and other clinical indicators between the two groups. In WF group, the ucOC levels were significantly higher than those in the non-WF group (10.3 ± 0.8 vs. 3.4 ± 0.9 ng/mL; P < 0.01), similarly, the RANKL levels in the WF group were higher than those in the non-WF group (0.60 ± 0.06 vs. 0.37 ± 0.05 ng/mL; P = 0.007). Moreover, RH-PAT index was significantly lower in the WF group compared to those in the non-WF group (1.48 ± 0.11 vs. 1.88 ± 0.12; P = 0.017).

Conclusions

Long-term warfarin therapy may be associated with bone mineral loss and vascular calcification in 60–80 year old hypertensive patients.

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Stroke prevention by warfarin has been an integral part in the management of atrial fibrillation.

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Warfarin prevents the activation of vitamin K-dependent proteins, MGP and Gas-6.

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Long-term warfarin therapy increases the serum levels of ucOC and RANKL.

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Long-term warfarin therapy is associated with vascular endothelial dysfunction.

Vitamin D in epilepsy: vitamin D levels in epilepsy patients, patients on antiepileptic drug polytherapy and drug-resistant epilepsy sufferers

The objective of this study was to assess vitamin D levels in epileptic patients and to compare its serum levels in patients on antiepileptic monotherapy and polytherapy. We analyzed the serum 25-hydroxy (25-OH) vitamin D levels in 98 consecutive subjects (43 epileptic patients and 55 non-epileptics). Factors influencing its serum levels such as degree of sun exposure, physical activity and dietary intake were taken into consideration. Overall, 41% had deficient, 49% had insufficient and 9% had sufficient levels of serum vitamin D. Elderly individuals (>60 years) and people employed in offices and schools had lower blood vitamin D levels. Across both the sexes, epileptic patients and non-epileptics, epileptic patients on monotherapy and polytherapy and patients with drug-responsive and -resistant seizures, there were no significant differences in serum 25-OH vitamin D levels. Our study shows that people with epilepsy suffer with vitamin D deficiency along with their normal peers.