Exposure to CYP3A4-inducing and CYP3A4-non-inducing antiepileptic agents and the risk of fractures

Liver enzyme inducing anticonvulsant drug use is associated with prevalent vertebral fracture

Among those who use of liver-enzyme inducing anticonvulsant medication for more than 2 years, 27% have a prevalent vertebral fracture on vertebral fracture assessment (VFA) lateral spine imaging. VFA imaging at the time of bone densitometry may be appropriate for older individuals who are chronic users of these medications.

PURPOSE

It is unclear whether prevalent vertebral fractures are associated with use of anticonvulsant drugs, especially those that induce liver enzymes (LEI) that metabolize drugs and vitamin D. Our purpose was to estimate the prevalence of vertebral fracture on densitometric lateral spine images according to duration of prior anticonvulsant medication use.

METHODS

Our study population was 11,822 individuals (mean [sd] age 76.1 [6.8] years, 94% female) who had bone densitometry with VFA between 2010 and 2018. Cumulative prior exposure to LEI anticonvulsants (carbamazepine, phenobarbital, phenytoin, valproic acid, n = 538), non-LEI anticonvulsants (clonazepam, gabapentin, levetiracetam, others, n = 2786), and other non-clonazepam benzodiazepines (n = 5082) was determined using linked pharmacy records. Prevalent vertebral fractures were identified on VFA images using the modified ABQ method. Logistic regression models were used to estimate the association of anticonvulsant drug exposure with prevalent vertebral fractures.

RESULTS

Prevalence of one or more vertebral fractures was 16.1% for the entire analytic cohort, and 27.0%, 19.0%, and 18.5% for those with ≥ 2 years of prior LEI anticonvulsant use, non-LEI anticonvulsant use, and other benzodiazepine use, respectively. Adjusted for multiple covariates, use of prior LEI anticonvulsant medication for ≥ 2 years was associated with prevalent fracture on VFA (OR 1.48 [95% CI 1.04, 2.10]).

CONCLUSION

LEI anticonvulsant use for ≥ 2 years is associated with higher vertebral fracture prevalence. Lateral spine VFA imaging at the time of bone densitometry may be appropriate for older individuals who have used LEI anticonvulsant medications for ≥ 2 years.

Complications associated with the use of enzyme-inducing and non-enzyme-inducing anti-seizure medications in the Japanese population: A retrospective cohort study

OBJECTIVE

Enzyme-inducing anti-seizure medications (EIASMs) may contribute to the development of complications such as fracture and cardiovascular disease. The objective of the study was to determine whether the use of EIASMs is associated with a higher risk of fracture and cardiovascular outcome in young Japanese patients with epilepsy.

METHOD

Adult patients diagnosed with epilepsy and initiated a monotherapy with an anti-seizure medication (ASM) between 2008 and 2018 were included in the study. The primary outcomes were the occurrence of acute myocardial infarction (AMI) or stroke. The secondary outcome was fracture. We performed a propensity score-matched analysis (1:1) to control for imbalances in patient characteristics, and the matched hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models.

RESULT

Of the 7115 eligible patients, 626 (8.79%) initiated treatment with EIASMs. The median age of the patients was 44 years (interquartile range: 31-54 years), and 56.2% were male. Propensity score matching generated 626 matched pairs of patients treated with EIASMs and non-EIASMs. There were no significant differences in the risk of stroke (EIASM group: n = 28[4.47%], non-EIASM group: n = 22[3.51%], HR: 1.47, 95% CI: 0.79-2.72, p = 0.22) or fracture (EIASM group: n = 7[1.12%], non-EIASM group: n = 5[0.80%], HR: 1.00, 95% CI: 0.29-3.45, p = 1.00) between the two groups. The hazard ratio for the occurrence of AMI could not be calculated due to the small number of events (EIASM group: n = 0[0.00], non-EIASM group: n = 2[0.32]).

SIGNIFICANCE

Our cohort study did not find increased risk of the occurrence of stroke, AMI, or fracture hospitalization with the use of enzyme-inducing ASMs. Although the findings suggested that exposure to EIASMs does not appear to increase the risk of complications in young patients, caution should be taken as patients with epilepsy tend to take medication in the long run.

The 2018 European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation

The current manuscript is the second update of the original Practical Guide, published in 2013 [Heidbuchel et al. European Heart Rhythm Association Practical Guide on the use of new oral anticoagulants in patients with non-valvular atrial fibrillation. Europace 2013;15:625-651; Heidbuchel et al. Updated European Heart Rhythm Association Practical Guide on the use of non-vitamin K antagonist anticoagulants in patients with non-valvular atrial fibrillation. Europace 2015;17:1467-1507]. Non-vitamin K antagonist oral anticoagulants (NOACs) are an alternative for vitamin K antagonists (VKAs) to prevent stroke in patients with atrial fibrillation (AF) and have emerged as the preferred choice, particularly in patients newly started on anticoagulation. Both physicians and patients are becoming more accustomed to the use of these drugs in clinical practice. However, many unresolved questions on how to optimally use these agents in specific clinical situations remain. The European Heart Rhythm Association (EHRA) set out to coordinate a unified way of informing physicians on the use of the different NOACs. A writing group identified 20 topics of concrete clinical scenarios for which practical answers were formulated, based on available evidence. The 20 topics are as follows i.e., (1) Eligibility for NOACs; (2) Practical start-up and follow-up scheme for patients on NOACs; (3) Ensuring adherence to prescribed oral anticoagulant intake; (4) Switching between anticoagulant regimens; (5) Pharmacokinetics and drug-drug interactions of NOACs; (6) NOACs in patients with chronic kidney or advanced liver disease; (7) How to measure the anticoagulant effect of NOACs; (8) NOAC plasma level measurement: rare indications, precautions, and potential pitfalls; (9) How to deal with dosing errors; (10) What to do if there is a (suspected) overdose without bleeding, or a clotting test is indicating a potential risk of bleeding; (11) Management of bleeding under NOAC therapy; (12) Patients undergoing a planned invasive procedure, surgery or ablation; (13) Patients requiring an urgent surgical intervention; (14) Patients with AF and coronary artery disease; (15) Avoiding confusion with NOAC dosing across indications; (16) Cardioversion in a NOAC-treated patient; (17) AF patients presenting with acute stroke while on NOACs; (18) NOACs in special situations; (19) Anticoagulation in AF patients with a malignancy; and (20) Optimizing dose adjustments of VKA. Additional information and downloads of the text and anticoagulation cards in different languages can be found on an EHRA website (www.NOACforAF.eu).

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.

Assessment of Sex Differences in Fracture Risk Among Patients With Anorexia Nervosa: A Population-Based Cohort Study Using The Health Improvement Network

Though previous studies have demonstrated an increased fracture risk in females with anorexia nervosa (AN), fracture risk in males is not well characterized. The objective of this study was to examine sex differences in fracture risk and site-specific fracture incidence in AN. We performed a population-based retrospective cohort study using The Health Improvement Network (THIN; a large database of anonymized electronic medical records collected at primary care clinics throughout the United Kingdom). The median calendar year for the start of the observation period was 2004-2005. We identified 9239 females and 556 males <60 years of age with AN, and 97,889 randomly selected sex-, age-, and practice-matched participants without eating disorders (92,329 females and 5560 males). Multivariable Cox regression was used to estimate the hazard ratio (HR) for incident fracture. Median age at start of observation was 29.8 years in females and 30.2 years in males. The HR for fracture associated with AN differed by sex and age (interaction p = 0.002). Females with AN had an increased fracture risk at all ages (HR, 1.59; 95% confidence interval [CI], 1.45 to 1.75). AN was associated with a higher risk of fracture among males >40 years of age (HR, 2.54; 95% CI, 1.32 to 4.90; p = 0.005) but not among males ≤40 years. Females with AN had a higher risk of fracture at nearly all anatomic sites. The greatest excess fracture risk was noted at the hip/femur (HR, 5.59; 95% CI, 3.44 to 9.09) and pelvis (HR, 4.54; 95% CI, 2.42 to 8.50) in females and at the vertebrae (HR, 7.25; 95% CI, 1.21 to 43.45) for males with AN. AN was associated with higher incident fracture risk in females across all age groups and in males >40 years old. Sites of highest fracture risk include the hip/femur and pelvis in females and vertebrae in males with AN. © 2016 American Society for Bone and Mineral Research.

Type 1 diabetes is associated with an increased risk of fracture across the life span: a population-based cohort study using The Health Improvement Network (THIN)

OBJECTIVE

This study was conducted to determine if type 1 diabetes is associated with an increased risk of fracture across the life span.

RESEARCH DESIGN AND METHODS

This population-based cohort study used data from The Health Improvement Network (THIN) in the U.K. (data from 1994 to 2012), in which 30,394 participants aged 0-89 years with type 1 diabetes were compared with 303,872 randomly selected age-, sex-, and practice-matched participants without diabetes. Cox regression analysis was used to determine hazard ratios (HRs) for incident fracture in participants with type 1 diabetes.

RESULTS

A total of 334,266 participants, median age 34 years, were monitored for 1.9 million person-years. HR were lowest in males and females age <20 years, with HR 1.14 (95% CI 1.01-1.29) and 1.35 (95% CI 1.12-1.63), respectively. Risk was highest in men 60-69 years (HR 2.18 [95% CI 1.79-2.65]), and in women 40-49 years (HR 2.03 [95% CI 1.73-2.39]). Lower extremity fractures comprised a higher proportion of incident fractures in participants with versus those without type 1 diabetes (31.1% vs. 25.1% in males, 39.3% vs. 32% in females; P < 0.001). Secondary analyses for incident hip fractures identified the highest HR of 5.64 (95% CI 3.55-8.97) in men 60-69 years and the highest HR of 5.63 (95% CI 2.25-14.11) in women 30-39 years.

CONCLUSIONS

Type 1 diabetes was associated with increased risk of incident fracture that began in childhood and extended across the life span. Participants with type 1 diabetes sustained a disproportionately greater number of lower extremity fractures. These findings have important public health implications, given the increasing prevalence of type 1 diabetes and the morbidity and mortality associated with hip fractures.

Risk of fracture in urolithiasis: a population-based cohort study using the health improvement network

BACKGROUND AND OBJECTIVES

Studies have shown decreased bone mineral density in individuals with urolithiasis, but their burden of fracture remains unclear. This study sought to determine whether urolithiasis is associated with increased fracture risk across the lifespan and to delineate sex effects.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A population-based retrospective cohort study using The Health Improvement Network was performed. The median calendar year for the start of the observation period was 2004 (1994-2012). This study identified 51,785 participants with ≥1 of 87 diagnostic codes for urolithiasis and 517,267 randomly selected age-, sex-, and practice-matched participants. Cox regression was used to estimate the hazard ratio (HR) for first fracture. Fractures identified using diagnostic codes were classified by anatomic site.

RESULTS

Median age was 53 years, and 67% of participants were men, confirming their greater urolithiasis burden. Median time from urolithiasis diagnosis to fracture was 10 years. The HR for fracture associated with urolithiasis differed by sex and age (P for interactions, P≤0.003). In men, the adjusted HR was greatest in adolescence (1.55; 95% confidence interval [95% CI], 1.07 to 2.25) with an overall HR of 1.10 (95% CI, 1.05 to 1.16). Urolithiasis was associated with higher fracture risk in women aged 30-79 years (HR, 1.17-1.52), and was highest in women aged 30-39 years (HR, 1.52; 95% CI, 1.23 to 1.87). Peak background fracture rates were highest in boys aged 10-19 years and in women aged 70-79 years. The incidence per 10,000 person-years in participants with versus without urolithiasis was 392 versus 258 in male participants aged 10-19 years, and 263 versus 218 in women aged 70-79 years. Distribution of fracture site within sex did not differ between participants with versus without urolithiasis.

CONCLUSIONS

Urolithiasis was associated with higher incident fracture risk. The significantly higher risk at times of peak background fracture incidence in adolescent boys and elderly women has profound public health implications.

Association between use of antiepileptic drugs and fracture risk: a systematic review and meta-analysis

BACKGROUND

It has been shown that antiepileptic drugs (AEDs) may have a detrimental effect on bone health and translate into an increased risk of bone fracture. We aimed to comprehensively evaluate the association between use of AEDs and fracture risk.

METHODS

We searched NCBI (PubMed), ISI Web of Science, the Cochrane Library and EMBASE databases for studies reporting fracture risk among users of AEDs. Random-effects meta-analysis was used to pool results across studies.

RESULTS

Twenty-two studies met the inclusion criteria. Overall, there was a significant increase in fracture risk among users of AEDs involving 1,292,910 participants, with a mean/median age of 36-82 years (relative risk (RR)=1.86; 95% confidence interval (CI) 1.62-2.12). When we limited the studies to those on osteoporosis-related fractures, the RR was still significant. Both liver enzyme-inducing antiepileptic drugs (LEI AEDs) and non-LEI AEDs were associated with an increase in fracture risk, although the estimate for LEI AEDs was higher than that of non-LEI AEDs (RR=1.18; 95% CI 1.11-1.25). For some specific AEDs, use of phenobarbiturate (PB), topiramate (TPM) and phenytoin (PHT) suggested an increase in fracture risk of 78%, 39% and 70%, respectively.

CONCLUSIONS

The study suggests a robust association between use of AEDs and fracture risk (particularly for LEI AEDs). It also suggests that several specific AEDs such as PB, TPM and PHT may be associated with an increased risk of fracture.