Effect of Concomitant Use of Benzodiazepines and Other Drugs on the Risk of Injury in a Veterans Population

Population-based screening to detect benzodiazepine drug-drug-drug interaction signals associated with unintentional traumatic injury

Drug interactions involving benzodiazepines and related drugs (BZDs) are increasingly recognized as a contributor to increased risk of unintentional traumatic injury. Yet, it remains unknown to what extent drug interaction triads (3DIs) may amplify BZDs' inherent injury risk. We identified BZD 3DI signals associated with increased injury rates by conducting high-throughput pharmacoepidemiologic screening of 2000-2019 Optum's health insurance data. Using self-controlled case series design, we included patients aged ≥ 16 years with an injury while using a BZD + co-dispensed medication (i.e., base pair). During base pair-exposed observation time, we identified other co-dispensed medications as candidate interacting precipitants. Within each patient, we compared injury rates during time exposed to the drug triad versus to the base pair only using conditional Poisson regression, adjusting for time-varying covariates. We calculated rate ratios (RRs) with 95% confidence intervals (CIs) and accounted for multiple estimation via semi-Bayes shrinkage. Among the 65,123 BZD triads examined, 79 (0.1%) were associated with increased injury rates and considered 3DI signals. Adjusted RRs for signals ranged from 3.01 (95% CI = 1.53-5.94) for clonazepam + atorvastatin with cefuroxime to 1.42 (95% CI = 1.00-2.02, p = 0.049) for alprazolam + hydrocodone with tizanidine. These signals may help researchers prioritize future etiologic studies to investigate higher-order BZD interactions.

Analysis of fall-related adverse events among older adults using the Japanese Adverse Drug Event Report (JADER) database

Background

Falls are a common but serious problem in older adults, and may lead to fractures and bleeding. As many factors, such as medication, aging, and comorbid diseases may simultaneously affect fall-related adverse events (AEs) in older adults, we evaluated the association between fall-related AEs and the use of medication, aging, and comorbid diseases using the Japanese Adverse Drug Event Report (JADER) database.

Methods

We analyzed reports of fall-related AEs associated with α-blockers, diuretics, calcium channel blockers, central nervous system (CNS)-active drugs (opioids, benzodiazepines, hypnotics and sedatives, non-selective monoamine reuptake inhibitors, and selective serotonin reuptake inhibitors (SSRI)) in the JADER database using the reporting odds ratio (ROR). For the definition of falls, we used the Preferred Terms of The Medical Dictionary for Regulatory Activities (MedDRA). We used the association rule mining technique to discover undetected associations, such as potential risk factors.

Results

The JADER database comprised 430,587 reports between April 2004 and November 2016. The RORs (95% CI) of α-blockers, diuretics, calcium channel blockers, opioids, benzodiazepines, hypnotics and sedatives, non-selective monoamine reuptake inhibitors, and SSRIs were 1.63 (1.27–2.09), 0.74 (0.63–0.86), 1.26 (1.15–1.38), 0.93 (0.80–1.07), 1.83 (1.68–2.01), 1.55 (1.12–2.14), 2.31 (1.82–2.95), and 2.86 (2.49–3.29), respectively. From the lift value in the association rule mining, the number of administered CNS-active drugs and patient age were associated with fall-related AEs. Furthermore, the scores of lift for patients with herpes zoster administered calcium channel blockers or benzodiazepines and patients with dementia administered benzodiazepines were high.

Conclusion

Our results suggest that the number of administered CNS-active drugs and patient age are both associated with fall-related AEs. We recommend that patients with herpes zoster treated with calcium channel blockers and benzodiazepines be closely monitored for fall-related AEs.

Initiation and long-term use of benzodiazepines and Z-drugs in bipolar disorder

OBJECTIVES

Increasing evidence points to the harmful effects of long-term benzodiazepine treatment. Our objective was to study the incidence of, and predictors for, long-term use of benzodiazepines and Z-drugs in bipolar disorder.

METHODS

We conducted a population-based cohort study, using data from Swedish national registers. Swedish residents aged 18-75 years with a recorded diagnosis of bipolar disorder or mania between July 2006 and December 2012, and no history of benzodiazepine/Z-drug use in the past year, were included. Patients were followed for 1 year with regard to prescription fills of benzodiazepines/Z-drugs. Initiators were followed for another year during which continuous use for >6 months was defined as "long-term". Patient and prescription characteristics were investigated as potential predictors for long-term use in multivariate logistic regression models.

RESULTS

Out of the 21 883 patients included, 29% started benzodiazepine/Z-drug treatment, of whom one in five became long-term users. Patients who were prescribed clonazepam or alprazolam had high odds for subsequent long-term use (adjusted odds ratios [aORs] 3.78 [95% confidence interval (CI) 2.24-6.38] and 2.03 [95% CI 1.30-3.18], respectively), compared to those prescribed diazepam. Polytherapy with benzodiazepines/Z-drugs also predicted long-term use (aOR 2.46, 95% CI 1.79-3.38), as did age ≥60 years (aOR 1.93, 95% CI 1.46-2.53, compared to age <30 years), and concomitant treatment with psychostimulants (aOR 1.78, 95% CI 1.33-2.39).

CONCLUSIONS

The incidence of subsequent long-term use among bipolar benzodiazepine initiators is high. Patients on clonazepam, alprazolam or benzodiazepine/Z-drug polytherapy have the highest risk of becoming long-term users, suggesting that these treatments should be used restrictively.

Polypharmacy including falls risk-increasing medications and subsequent falls in community-dwelling middle-aged and older adults

BACKGROUND

polypharmacy is an important risk factor for falls, but recent studies suggest only when including medications associated with increasing the risk of falls.

DESIGN

a prospective, population-based cohort study.

SUBJECTS

6,666 adults aged ≥50 years from The Irish Longitudinal study on Ageing.

METHODS

participants reported regular medication use at baseline. Any subsequent falls, any injurious falls and the number of falls were reported 2 years later. The association between polypharmacy (>4 medications) or fall risk-increasing medications and subsequent falls or injurious falls was assessed using modified Poisson regression. The association with the number of falls was assessed using negative binomial regression.

RESULTS

during follow-up, 231 falls per 1,000 person-years were reported. Polypharmacy including antidepressants was associated with a greater risk of any fall (adjusted relative risk (aRR) 1.28, 95% CI 1.06-1.54), of injurious falls (aRR 1.51, 95% CI 1.10-2.07) and a greater number of falls (adjusted incident rate ratio (aIRR) 1.60, 95% CI 1.19-2.15), but antidepressant use without polypharmacy and polypharmacy without antidepressants were not. The use of benzodiazepines was associated with injurious falls when coupled with polypharmacy (aRR 1.40, 95% CI 1.04-1.87), but was associated with a greater number of falls (aIRR 1.32, 95% CI 1.05-1.65), independent of polypharmacy. Other medications assessed, including antihypertensives, diuretics and antipsychotics, were not associated with outcomes.

CONCLUSION

in middle-aged and older adults, polypharmacy, including antidepressant or benzodiazepine use, was associated with injurious falls and a greater number of falls.

Impact of specific Beers Criteria medications on associations between drug exposure and unplanned hospitalisation in elderly patients taking high-risk drugs: a case-time-control study in Western Australia

BACKGROUND

Certain broad medication classes have previously been associated with high rates of hospitalisation due to related adverse events in elderly Western Australians, based on clinical coding recorded on inpatient summaries. Similarly, some medications from the Beers Criteria, considered potentially inappropriate in older people, have been linked with an increased risk of unplanned hospitalisation in this population.

OBJECTIVE

Our objective was to determine whether risk estimates of drug-related hospitalisations are altered in elderly patients taking 'high-risk drugs' (HRDs) when specific Beers potentially inappropriate medications (PIMS) are taken into consideration.

METHODS

Using the pharmaceutical claims of 251,305 Western Australians aged ≥65 years (1993-2005) linked with other health data, we applied a case-time-control design to estimate odds ratios (ORs) for unplanned hospitalisations associated with anticoagulants, antirheumatics, opioids, corticosteroids and four major cardiovascular drug groups, from which attributable fractions (AFs), number and proportion of drug-related admissions were derived. The analysis was repeated, taking into account exposure to eight specific PIMs, and results were compared.

RESULTS

A total of 1,899,699 index hospitalisations were involved. Of index subjects, 12-57 % were exposed to each HRD at the time of admission, although the proportions taking both an HRD and one of the selected PIMs were much lower (generally ≤2 %, but as high as 8 % for combinations involving temazepam and for most PIMs combined with hypertension drugs). Included PIMs (indomethacin, naproxen, temazepam, oxazepam, diazepam, digoxin, amiodarone and ferrous sulphate) all tended to increase ORs, AFs and drug-related hospitalisation estimates in HRD combinations, although this was less evident for opioids and corticosteroids. Indomethacin had the greatest overall impact on HRD ORs/AFs. Indomethacin (OR 1.40; 95 % confidence interval [CI] 1.27-1.54) and naproxen (OR 1.22; 1.14-1.31) were associated with higher risks of unplanned hospitalisation than other antirheumatics (overall OR 1.09; 1.06-1.12). Similarly, among cardiac rhythm regulators, amiodarone (OR 1.22; 1.13-1.32) was riskier than digoxin (OR 1.08; 1.04-1.13). For comparisons of drug-related hospitalisation estimates, temazepam yielded the greatest absolute increases, especially with hypertension drugs.

CONCLUSIONS

Indomethacin and temazepam should be prescribed cautiously in elderly patients, especially in drug combinations. Furthermore, it appears other antirheumatics should be favoured over indomethacin/naproxen and, in situations where both drugs may be appropriate, digoxin over amiodarone. Our methodology may help assess the safety of new medications in drug combinations in preliminary pharmacovigilance investigations.

Effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and relevant pharmacological interventions on fall risk in elderly patients

BACKGROUND

Falls among the elderly are an issue internationally and a public health problem that brings substantial economic and quality-of-life burdens to individuals and society. Falls prevention is an important measure of nursing quality and patient safety. Numerous studies have evaluated the association of medication use with fall risk in elderly patients. However, an up-to-date review has not been available to summarize the multifaceted pharmaceutical concerns in the prevention of medication-related falls.

MATERIALS AND METHODS

Relevant literature was identified by performing searches in PubMed, Web of Science, and the Cochrane Library, covering the period until February 2014. We included studies that described an association between medications and falls, and effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and pharmacological interventions on fall risk in elderly patients. The full text of each included article was critically reviewed, and data interpretation was performed.

RESULTS

Fall-risk-increasing drugs (FRIDs) include central nervous system-acting agents, cough preparations, nonsteroidal anti-inflammatory drugs, anti-Alzheimer's agents, antiplatelet agents, calcium antagonists, diuretics, α-blockers, digoxin, hypoglycemic drugs, neurotoxic chemotherapeutic agents, nasal preparations, and antiglaucoma ophthalmic preparations. The degree of medication-related fall risk was dependent on one or some of the following factors: drug pharmacokinetic/pharmacodynamic properties (eg, elimination half-life, metabolic pathway, genetic polymorphism, risk rating of medications despite belonging to the same therapeutic class) and/or characteristics of medication use (eg, number of medications and drug-drug interactions, dose strength, duration of medication use and time since stopping, medication change, prescribing appropriateness, and medication adherence). Pharmacological interventions, including withdrawal of FRIDs, pharmacist-conducted clinical medication review, and computerized drug alerts, were effective in reducing fall risk.

CONCLUSION

Based on the literature review, clear practical recommendations for clinicians to prevent falls in the elderly included making a list of FRIDs, establishing a computerized alert system for when to e-prescribe FRIDs, seeking an alternative drug with lower fall risk, withdrawing FRIDs if clinically indicated, taking pertinent cautions when the use of FRIDs cannot be avoidable, paying attention to prescribing appropriateness, simplifying the medication regimen, strengthening pharmacist-conducted clinical medication review, ensuring the label of each FRID dispensed contains a corresponding warning sign, being careful when medication change occurs, enhancing medication adherence, and mandating for periodic reassessment of potential risk associated with the patient's medication regimen. Further studies should be conducted in this area, such as investigating whether medication reconciliation and improving medication adherence could decrease the rate of falls.

Risk of road accident associated with the use of drugs: a systematic review and meta-analysis of evidence from epidemiological studies

This paper is a corrigendum to a previously published paper where errors were detected. The errors have been corrected in this paper. The paper is otherwise identical to the previously published paper. A systematic review and meta-analysis of studies that have assessed the risk of accident associated with the use of drugs when driving is presented. The meta-analysis included 66 studies containing a total of 264 estimates of the effects on accident risk of using illicit or prescribed drugs when driving. Summary estimates of the odds ratio of accident involvement are presented for amphetamines, analgesics, anti-asthmatics, anti-depressives, anti-histamines, benzodiazepines, cannabis, cocaine, opiates, penicillin and zopiclone (a sleeping pill). For most of the drugs, small or moderate increases in accident risk associated with the use of the drugs were found. Information about whether the drugs were actually used while driving and about the doses used was often imprecise. Most studies that have evaluated the presence of a dose-response relationship between the dose of drugs taken and the effects on accident risk confirm the existence of a dose-response relationship. Use of drugs while driving tends to have a larger effect on the risk of fatal and serious injury accidents than on the risk of less serious accidents (usually property-damage-only accidents). The quality of the studies that have assessed risk varied greatly. There was a tendency for the estimated effects of drug use on accident risk to be smaller in well-controlled studies than in poorly controlled studies. Evidence of publication bias was found for some drugs. The associations found cannot be interpreted as causal relationships, principally because most studies do not control very well for potentially confounding factors.

National Veterans Health Administration Hospitalizations for Syncope Compared to Acute Myocardial Infarction, Fracture, or Pneumonia in Community-Dwelling Elders: Outpatient Medication and Comorbidity Profiles

The authors used 2 national Veterans Health Administration databases to identify outpatient medications and all 30 Elixhauser comorbidities for 2579 unique patients, age 65+ years, hospitalized for syncope in fiscal year 2004. For comparison, we identified other elderly patients hospitalized with acute myocardial infarction (N = 4491), fracture (N = 2797), or pneumonia (N = 9473). The categories of medications included drugs that affect the cardiovascular, central nervous, or the muscular skeletal system. The most notable differences between syncope compared to acute myocardial infarction patients occurred in central nervous system drugs in anticonvulsants/barbiturates, antidepressants, antihistamine/antinauseants, antipsychotics, and cholinesterase inhibitors (P < .0018). Comparing syncope patients with fracture patients, the central nervous medication profile was similar, but the cardiovascular medication profile differed (P < .0018); their hypertension comorbidities also differed (60.45% vs 46.34%); (P < .0016). These findings indicate significant potential associations that warrant further study. Studies linking national outpatient medications to hospitalizations for specific conditions can foster the development of more proactive pharmacovigilance systems.

The association of opioid use with incident lower extremity fractures in spinal cord injury

OBJECTIVE

To determine the association between opioid use and lower extremity fracture risk in men with spinal cord injury (SCI).

DESIGN

Retrospective cohort study.

SETTING

Veterans Affairs Healthcare System.

PARTICIPANTS

In total, 7447 male Veterans with a history of a traumatic SCI identified from the Veterans Affairs (VA) Spinal Cord Dysfunction Registry (SCD) from September 2002 through October 2007 and followed through October 2010.

OUTCOME MEASURES

Incident lower extremity fractures by use of opioids.

RESULTS

In individuals identified from the VA SCD Registry 2002-2007, opioid use was quite common, with approximately 70% of the cohort having received a prescription for an opioid. Overall, there were 892 incident lower extremity fractures over the time period of this study (597 fractures in the opioid users and 295 fractures in the non-opioid users). After adjusting for covariates, there was a statistically significant relationship between opioid use and increased risk for lower extremity fractures (hazard ratio 1.82 (95% confidence interval 1.59-2.09)). Shorter duration of use (<6 months) and higher doses were positively related to fracture risk (P < 0.0001).

CONCLUSIONS

Opioid use is quite common in SCI and is associated with an increased risk for lower extremity fractures. Careful attention to fracture prevention is warranted in patients with SCI, particularly upon initiation of an opioid prescription and when higher doses are used.

Potentially harmful drug-drug interactions in the elderly: a review

BACKGROUND

Elderly patients are vulnerable to drug interactions because of age-related physiologic changes, an increased risk for disease associated with aging, and the consequent increase in medication use.

OBJECTIVE

The purpose of this narrative review was to describe findings from rigorously designed observational cohort and case-control studies that have assessed specific drug interactions in elderly patients.

METHODS

The PubMed and International Pharmaceutical Abstracts databases were searched for studies published in English over the past 10 years (December 2000-December 2010) using relevant Medical Subject Headings terms (aged; aged, 80 and over; and drug interactions) and search terms (drug interaction and elderly). Search strategies were saved and repeated through September 2011 to ensure that the most recent relevant published articles were identified. Additional articles were found using a search of review articles and reference lists of the identified studies. Studies were included if they were observational cohort or case-control studies that reported specific adverse drug interactions, included patients aged ≥65 years, and evaluated clinically meaningful end points. Studies were excluded if they used less rigorous observational designs, assessed pharmacokinetic/pharmacodynamic properties, evaluated drug-nutrient or drug-disease interactions or interactions of drug combinations used for therapeutic benefit (eg, dual antiplatelet therapy), or had inconclusive evidence.

RESULTS

Seventeen studies met the inclusion criteria. Sixteen studies reported an elevated risk for hospitalization in older adults associated with adverse drug interactions. The drug interactions included: angiotensin-converting enzyme (ACE) inhibitors and potassium-sparing diuretics, ACE inhibitors or angiotensin receptor blockers and sulfamethoxazole/trimethoprim, benzodiazepines or zolpidem and interacting medications, calcium channel blockers and macrolide antibiotics, digoxin and macrolide antibiotics, lithium and loop diuretics or ACE inhibitors, phenytoin and sulfamethoxazole/trimethoprim, sulfonylureas and antimicrobial agents, theophylline and ciprofloxacin, and warfarin and antimicrobial agents or nonsteroidal anti-inflammatory drugs. One study reported the risk for breast cancer-related death as a function of paroxetine exposure among women treated with tamoxifen.

CONCLUSIONS

Several population-based studies have reported significant harm associated drug interactions in elderly patients. Increased awareness and interventions aimed at reducing exposure and minimizing the risks associated with potentially harmful drug combinations are needed.

Impact of drug interactions, dosage, and duration of therapy on the risk of hip fracture associated with benzodiazepine use in older adults

PURPOSE

To determine how concomitant use of potentially interacting drugs, drug dosage, and duration of therapy modify the risk of hip fracture associated with use of benzodiazepines and benzodiazepine-related drugs (BDZ) in older adults.

METHODS

A nested case-control study was conducted in Medicare patients 65 years or older, enrolled in the Pennsylvania drug assistance program (PACE) between 1994 and 2005. We included 17,198 patients with a hip fracture leading to hospitalization and 85,990 controls matched on hospitalization (index date). BDZ and interacting drug use within 2 weeks preceding the index date was determined using information on date of drug dispensing, days supplied, quantity dispensed, and strength. Date of the first BDZ prescription within the year preceding the index date was used as surrogate for duration of therapy.

RESULTS

While the adjusted relative risk (RR) for overall BDZ use and hip fracture was 1.2 (95% confidence interval 1.1, 1.2), the RRs for concomitant use of alprazolam, lorazepam, and zolpidem and their interacting drugs were 1.5 (1.3, 1.7), 1.9 (1.7, 2.2), and 1.7 (1.4, 2.0), and 2.1 (1.5, 2.8) for BDZ use initiated within 14 days preceding the index date. RR increased with increasing BDZ dose and was highest for defined daily BDZ doses >1 [RR: 1.3 (1.2, 1.5)].

CONCLUSIONS

BDZ associated hip fracture risk increases with concomitant use of interacting drugs, higher doses, and is highest at initiation. Clinicians should avoid concomitant use of BDZ and interacting drugs, because their impact on hip fracture risk is at least additive.

The relationship between benzodiazepine use and traffic accidents: A systematic literature review

In many countries, benzodiazepines are the most commonly used and misused psychoactive medicinal drugs. Results of epidemiological studies investigating the association between benzodiazepine use and traffic accidents seem to be inconclusive or inconsistent at first sight. However, the outcome of epidemiological studies may be influenced by several methodological factors like study design, study population, exposure measurement, outcome definitions and possible confounders. Our objective was to conduct a systematic literature review of epidemiological studies that investigated the association between benzodiazepine use and traffic accidents, including related outcomes like culpability and injury or accident severity. We searched EMBASE, PubMed and Forensic Science Abstracts 3/0 (FORS) for references included in these databases at 1 June 2009 using the term 'benzodiazepines' in combination with 'driving performance' or 'accident risk' or 'traffic accident'. For inclusion in this review, the study design had to be comparative, include road users involved in accidents and provide specific data about benzodiazepines. Sixty-six studies were included in the review. The study populations varied from the general (driving) population, accident-involved road users with or without injury and persons admitted to a hospital to fatally injured accident-involved drivers. Exposure assessment was performed by using toxicological results, prescription data or questionnaires. The divergent study populations and comparison groups and the variety of methods used to express the outcome of interest hampered comparison between results. Evidence is growing that exposure to benzodiazepines is related to increased accident risk. The literature indicates that the greatest accident risk is associated with the use of long half-life benzodiazepines, increasing dosage and the first few weeks of use of benzodiazepines. Clear evidence of increased culpability associated with benzodiazepine use is scarce. More research has to be done to elucidate the relationship between benzodiazepine use and injury severity.

Hospitalizations for poisoning by prescription opioids, sedatives, and tranquilizers

BACKGROUND

Unintentional poisoning deaths have been increasing dramatically over the past decade, and the majority of this increase has resulted from overdoses of specific prescription drugs. Despite this trend, there are limited existing data examining hospitalizations for poisonings, both unintentional and intentional, associated with prescription drugs. A better understanding of these hospitalizations may help identify high-risk populations in need of intervention to prevent subsequent mortality.

PURPOSE

This article aims to describe the incidence and characteristics of hospitalizations resulting from poisoning by prescription opioids, sedatives, and tranquilizers in the U.S. from 1999 to 2006 and make comparisons to hospitalizations for all other poisonings during this time period.

METHODS

Hospitalizations for poisonings were selected from the Nationwide Inpatient Sample (NIS), a stratified, representative sample of approximately 8 million hospitalizations each year, according to the principal discharge diagnosis. Intentionality of the poisoning was determined by external cause of injury codes. SAS callable SUDAAN software was used to calculate weighted estimates of poisoning hospitalizations by type and intentionality. Demographic and clinical characteristics of poisoning cohorts were compared. Data were analyzed in 2009.

RESULTS

From 1999 to 2006, U.S. hospitalizations for poisoning by prescription opioids, sedatives, and tranquilizers increased a total of 65%. This increase was double the increase observed in hospitalizations for poisoning by other drugs and substances. The largest increase in the number of hospitalized cases over the 7-year period was seen for poisonings by benzodiazepines, whereas the largest percentage increase was observed for methadone (400%). In comparison to patients hospitalized for poisoning from other substances, those hospitalized for prescription opioids, sedatives, and tranquilizers were more likely to be women, aged >34 years, and to present to a rural or urban nonteaching hospital.

CONCLUSIONS

Prescription opioids, sedatives, and tranquilizers are an increasing cause of hospitalization. The hospital admission provides an opportunity to better understand the contextual factors contributing to these cases, which may aid in the development of targeted prevention strategies.

All-cause mortality rates of hip fractures treated in the VHA: do they differ from Medicare facilities?

PURPOSE

To estimate the 1-year all-cause mortality rates for hip fracture (HFx) patients hospitalized at Veterans Health Administration (VHA) facilities and compare with previous published mortality rates for veterans treated in Medicare facilities.

METHODS

In total, 7 years of VHA discharge data on HFxs for 12,539 patients age 65 and older were combined with national death registry data. We performed a 1-year survival analysis using the Cox proportional hazard method.

RESULTS

The adjusted rates for veterans treated in the VHA (30 days=9.3%, 90 days=17.5%, 180 days=23.3%, 365 days=29.8%) were similar to veterans treated in Medicare facilities (30 days=8.9%, 90 days=15.6%, 180 days=21.8%, 365 days=29.9%). For veterans treated for a HFx in Medicare facilities, the average length of stay was 7 days and 49% were discharged to a nursing home. Veterans treated in the VHA had an average length of stay of 14 days and only 35% were discharged to a nursing home.

CONCLUSIONS

Our study suggests no difference in HFx-adjusted mortality rates between the VHA and Medicare facilities. Given the institutional factor differences between Medicare and the VHA, future study and comparison of health outcomes for nursing home HFx patients and related costs between these two health care programs may contribute to the on-going health care reform debate.

Predictors of the incidence and discontinuation of long-term use of benzodiazepines: a population-based study

Long-term use of benzodiazepines (BZDs) has been linked with an array of negative health consequences and increased medical costs and social burden. In this study, we sought to investigate the factors accounting for differential risks in the process from incident BZD use to long-term use and discontinuation in the general population. On the basis of a random sample of 187,413 people enrolled in Taiwan's National Health Insurance program on January 1, 2000, data of 2000-2002 healthcare and pharmacological services utilization were retrieved. Long-term use (LTU) was defined by having received BZD prescriptions for 180 or more days within any given calendar year. Multivariate logistic regression analyses were carried out to assess the strength of associations while adjusting for the effects of individual sociodemographics, service providers, and pharmacological agents simultaneously. Results indicated that males, elderly, and those with physical or mental disorders were more likely to become long-term users of BZDs. Having received BZD prescriptions in multiple pharmacological agents, short-acting or mixed-type agents, and hypnotic indication were associated with a roughly 2- to 5-fold increased risk of BZD LTU soon after prescription initiation. With respect to discontinuation, the effects of pharmacological characteristics seem more salient as compared to those of individual and service-provider factors. Future strategies targeting individual factors and modifying service-provider prescription behaviors may be considered to reduce possible negative consequences of BZD LTU.

Benzodiazepines and injurious falls in community dwelling elders

BACKGROUND

Benzodiazepines are frequently used medications in the elderly, in whom they are associated with an increased risk of falling, with sometimes dire consequences.

OBJECTIVE

To estimate the impact of benzodiazepine-associated injurious falls in a population of elderly persons.

METHOD

A nested case-control study was conducted using data collected during 10 years of follow-up of the French PAQUID (Personnes Agées QUID) community-based cohort. The main outcome measure was the occurrence of an injurious fall, which was defined as a fall resulting in hospitalization, fracture, head trauma or death. Controls (3 : 1) were frequency-matched to cases. Benzodiazepine exposure was the use of benzodiazepines over the previous 2 weeks reported at the follow-up visit preceding the fall.

RESULTS

Benzodiazepine use was significantly associated with the occurrence of injurious falls, with a significant interaction with age. The adjusted odds ratio for injurious falls in subjects exposed to benzodiazepines was 2.2 (95% CI 1.4, 3.4) in subjects aged > or = 80 years and 1.3 (95% CI 0.9, 1.9) in subjects aged <80 years. The population attributable risk for injurious falls in subjects exposed to benzodiazepines was 28.1% (95% CI 16.7, 43.2) for subjects aged > or =80 years. The incidence of injurious falls in subjects aged > or = 80 years exposed to benzodiazepines in the PAQUID cohort was 2.8/100 person-years. Over 9% of these falls were fatal. According to these results and to recent population estimates, benzodiazepine use could be held responsible for almost 20 000 injurious falls in subjects aged > or = 80 years every year in France, and for nearly 1800 deaths.

CONCLUSION

Given the considerable morbidity and mortality associated with benzodiazepine use and the fact that existing good practice guidelines on benzodiazepines have not been effective in preventing their misuse (possibly because they have not been applied), new methods for limiting use of benzodiazepines in the elderly need to be found.

Somnolence effects of antipsychotic medications and the risk of unintentional injury

PURPOSE

This study examined the relationship between antipsychotic medications, categorized by published somnolence effects, and unintentional injury (UI).

METHODS

The study population included patients of 18-64 years of age in a healthcare insurance database with claims from 2001 to 2004 and diagnoses of schizophrenia or affective disorder. A nested case-control design was used with cases defined by an E-code claim (a specified external cause of injury) for selected UIs. For cases, the index date referred to the first injury. For controls, the "control index date" was the date of claim if there was only a single medical claim; for patients with > or =2 claims, one was selected at random as the "control index date." Both groups had a prescription for a first-generation antipsychotic (FGA) or second-generation antipsychotic (SGA) overlapping the index date. Potential somnolence effects were defined as: low (referent)--aripiprazole/ziprasidone; medium--risperidone; high--olanzapine/quetiapine: or any single FGA. Logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (CI) for UI, adjusted for gender, age, concomitant drug, and psychiatric diagnosis.

RESULTS

Among 648 cases and 5214 controls, high-somnolence SGAs were associated with an OR of 1.41 95%CI (1.03-1.93) for risk of UI, while medium-somnolence SGAs, and FGAs had ORs of 1.17 95%CI (0.83-1.64) and 1.17 95%CI (0.79-1.74), respectively. When quetiapine and olanzapine were disaggregated, ORs were 1.61 95%CI (1.15-2.25) and 1.25 95%CI (0.89-1.74), respectively.

CONCLUSIONS

High-somnolence SGAs may lead to UI among patients. When prescribing antipsychotics, clinicians should consider potential somnolence.

A national perspective of Medicare expenditures for elderly veterans with hip fractures

INTRODUCTION

The Centers for Medicare and Medicaid Services (CMS) recently announced that beginning in October 2008, Medicare will no longer reimburse hospitals for the costs of treating injuries from several preventable conditions, including inpatient falls resulting in hip fracture. If hospitals try to shift this care to other payers, elderly veterans who are dually eligible for care in Medicare and Veterans Health Administration (VHA) facilities may be adversely affected. As health care provided for a hip fracture can be substantial, the goal of this research was to calculate Medicare payments for a national cohort of elderly veterans with hip fractures, beginning with the first inpatient admission and continuing through one year.

METHODS

This was a retrospective, secondary data analysis of national VHA-eligible Medicare beneficiaries. The study population was 43,104 veterans with a hip fracture first admitted to a Medicare-eligible facility during 1999-2002. The estimation method was an ordinary least squares regression model of Medicare payments to providers for hip fracture patients over 4 time periods, up to 1 year after discharge, controlling for age, gender, inpatient length of stay, 1-year mortality, and selected Elixhauser comorbidities.

RESULTS

Medicare reimbursed providers for nearly $3 billion of health care for hip fracture patients the first year of injury. Approximately 71.4% ($49,544) of the total annual Medicare payments (for all services) occurred within the first 30 days of hospital admission. Inpatient and carrier (physician) providers received the majority of the payments. The average annual payment per individual was $69,389 (99% confidence interval: $68,539-$70,239). Almost 7 in 10 hip fracture patients obtained care in a skilled nursing facility (SNF) during the year, with these providers comprising only 12% of total annual Medicare payments. In this elderly veteran cohort, hip fracture patients with renal failure, diabetes, lymphoma, and metastatic cancer generated the highest payments.

CONCLUSION

This analysis provides proxy cost estimates for hip fracture patients useful for the forthcoming CMS reimbursement policy changes for inpatient fall-related injuries. The VHA and dually eligible elderly veterans could be disproportionately exposed to the economic consequences of the new CMS policy change.

Rehospitalization after hip fracture: predictors and prognosis from a national veterans study

OBJECTIVES

To estimate the risk and long-term prognostic significance of 30-day readmission postdischarge of a 4-year cohort of elderly veterans first admitted to Medicare hospitals for treatment of hip fractures (HFx), controlling for comorbidities.

DESIGN

Retrospective, national secondary data analysis.

SETTING

National Medicare and Veterans Health Administration (VHA) facilities.

PARTICIPANTS

The study cohort was 41,331 veterans with a HFx first admitted to a Medicare eligible facility during 1999 to 2002.

MEASUREMENTS

HFxs were linked with all other Medicare and VHA inpatient discharge files to capture dual inpatient use. Logistic regression was used to examine the relationship between 30-day readmission and age, sex, inpatient length of stay, and selected Elixhauser comorbidities.

RESULTS

Approximately 18.3% (7,579/41,331) of HFx patients were readmitted within 30 days. Of those with 30-day readmissions, 48.5% (3,675/7,579) died within 1 year, compared with 24.9% (8,388/33,752) of those without 30-day readmissions. Readmission risk was significantly greater in the presence of specific comorbidities, ranging from 11% greater risk for patients with fluid and electrolyte disorders (95% confidence interval (CI)=1.04-1.20) to 43% for renal failure (95% CI=1.29-1.60). For this cohort, cardiac arrhythmias (24%), chronic pulmonary disease (28%), and congestive heart failure (16%) were common comorbidities, and all affected the risk of 30-day readmission.

CONCLUSION

Patients with HFx with 30-day readmissions were nearly twice as likely to die within 1 year. Identification of several predictive comorbidities at discharge and examination of reasons for subsequent readmission suggests that readmission was largely due to active comorbid clinical problems. These comorbidity findings have implications for the current Centers for Medicare and Medicaid Services (CMS) pay-for-performance initiatives, especially those related to better coordination of care for patients with chronic illnesses. These comorbidity findings for elderly patients with HFx may also provide data to enable CMS and healthcare providers to more accurately differentiate between comorbidities and hospital-acquired complications under the current CMS initiative related to nonpayment for certain types of medical conditions and hospital acquired infections.

[Sleep disorders and hypnotic agents: medical, social and economical impact]

Insomnia is a subjective complaint relating to approximately 30% of the adult population in France, described by the patient as a difficulty of initiating and/or maintaining sleep. Its prevalence increases with age and sex: women are more affected than men (24% vs 14%). Insomnia is either occasional (20%), or chronic (10%). Chronic insomnia has an important impact on patients' everyday life e.g. fatigue, perturbed diurnal waking state, impaired quality-of-life... which results in lower work productivity and drowsiness as well as relational difficulties, absenteeism. About 80% of patients consult their general practitioner first. The aim of a hypnotic agent is to obtain sleep as physiological as possible. Benzodiazepines and benzodiazepines-like agents (zopiclone, zolpidem, zaleplon) are the most widely used hypnotics. However, their indications must be limited to occasional insomnia with a limited duration: less than four weeks. There is no advantage with using a combination of hypnotic agents, a practice which should be prohibited. Adverse effects can be serious, e.g. diurnal somnolence associated with risks of road accidents and, in the elderly, the risk of falls. After chronic use, hypnotics can be addictive, as their effects wear off in three to four weeks. After withdrawal, insomnia rebound is frequent. Use of hypnotics in association with alcohol is a well-known drug-addiction behavior. According to the French health insurance fund, 9% of the general population use hypnotics and about half of them regularly. Insurance refunds for hypnotics and sedatives reach more than 110 million euros annually. The efficiency of hypnotics wears off, quickly for benzodiazepines (three - four weeks), or less quickly for zopiclone and zolpidem (a few months). Insomnia is a major public health issue, each year 10% of the incident cases of insomnia treated by hypnotics joint the group of subjects with chronic insomnia. This failure to treat insomnia properly can be explained, at least in part, by several insufficiencies: physicians and pharmacists training, medical profession awareness, research, public information on the rules of good sleep (public health campaigns, booklets, role of physicians and the pharmacists).

Risk-adjusted mortality rates of elderly veterans with hip fractures

PURPOSE

The goal of this research was to estimate 12-month survival rates for a large sample of elderly veterans after hip fracture with a risk-adjusted model and to compare the results of men to those of women.

METHODS

The study design was a retrospective, secondary data analysis of national Veterans Health Administration (VHA) Medicare beneficiaries. The study population was 43,165 veterans with hip fracture first admitted to a Medicare-eligible facility during our specified enrollment period of 1999-2002. Measurement was a Cox proportional hazard model or survival analysis of hip fracture patients with an outcome of death over a 1 year period after discharge controlled by age, gender, and selected Elixhauser comorbidities.

RESULTS

The unadjusted, 1 year mortality rates (30 days = 9.7%, 90 days = 17.5%, 180 days = 24%, 365 days = 32.2%) were slightly higher than the adjusted rates (30 days = 8.9%, 90 days = 15.6%, 180 days = 21.8%, 1 year = 29.9%). The mortality odds for women 12 months after hip fracture were 18%, compared with 32% for men. The comorbidity adjustment suggested that the presence of metastatic cancer increased the risk of death by almost 4 times compared with those patients without this diagnosis. Other particularly high-risk conditions included congestive heart failure, renal failure, liver disease, lymphoma, and weight loss, each of which increased the 1 year mortality risk by approximately two-fold.

CONCLUSIONS

One in 3 elderly male veterans who sustain a hip fracture dies within 1 year. Our work represents the first large study of hip fractures with a predominantly male sample and confirms that men have a higher mortality risk than women, as reported by previous researchers who used smaller samples that were mostly female. Fracture patients with metastatic cancer, renal failure, lymphoma, weight loss, and liver disease have higher mortality risks. The adverse outcomes associated with hip fracture argue for clinical intervention strategies, such as gait and balance testing, and osteoporosis diagnosis that may prevent fractures in both genders.

National outpatient medication profiling: medications associated with outpatient fractures in community-dwelling elderly veterans

AIMS

The primary objective of this retrospective case-control study in an elderly veteran population was to assess the impact of specific medications with recognized side-effects that increase the risk of a fall and were prescribed prior to fractures treated in the outpatient setting compared with patients treated for nonspecific chest pain.

METHODS

Two national Veterans Health Administration (VHA) databases were used to identify 17 273 unique patients, aged > or =65 years, treated in outpatient settings with a fracture in fiscal year 2005, and for whom we could link to all of their outpatient prescriptions (809 536). For comparison, we identified other elderly patients with outpatient clinic visits for nonspecific chest pain (N = 62 331) for whom we could link with their 2 987 394 outpatient prescriptions. We categorized the fall-related medications as drugs that primarily affect the cardiovascular (CVS), the central nervous (CNS) or the muscular skeletal system (MSS).

RESULTS

Significant differences in the two patient groups occurred in the CNS category. Approximately 41% of the patients with fracture-coded encounters were prescribed CNS drugs compared with 31% of the patients in the comparison group (P < 0.0003). Finally, the use of muscle relaxants in the MSS category was significantly higher in the fracture group than in the nonspecific chest pain group.

CONCLUSIONS

Studies using administrative data can foster the development of more proactive pharmacovigilance systems and assist in formulary refinement, particularly in countries with national healthcare systems that have integrated patient data. Particular attention and monitoring of elderly patients taking CNS medications may be important for injury prevention.

Drugs and falls in community-dwelling older people: a national veterans study

OBJECTIVE

The aim of this study was to identify which specific medications within recognized major problematic drug categories that increase risk of falling were prescribed to veterans before their out-patient treatment for a fall.

METHODS

This was a retrospective, cross-sectional national secondary outpatient data analysis with an age- and sex-matched comparison group. The setting was the national Veterans Health Administration (VHA) ambulatory health care system in fiscal year (FY) 2004. The study population was VHA patients aged>or=65 years who had fall-related outpatient clinical health care encounters in FY 2004 (as indicated by diagnostic codes) and who received >or=1 outpatient medication during the study period. The age- and sex-matched comparison group consisted of an equal number of patients with nonspecific chest pain. The percentage of patients in each group receiving medications (at the time of the outpatient encounter) that affect the cardiovascular system (CVS), central nervous system (CNS), or musculoskeletal system (MSS) was compared with Bonferrom-adjusted P values.

RESULTS

The study sample consisted of 20,551 patients; the comparison group included the same number of patients. More patients with fall-coded encounters used CNS drugs than those with nonspecific chest pain (42.05% vs 29.29%). Also, within the CNS category, more patients with fall-coded encounters used antiparkinsonian medications (3.67% vs 1.32%), Alzheimer's disease medications (ie, cholinesterase inhibitors [5.40% vs 2.35%]), anticonvulsants/barbiturates (8.95% vs 5.18%), antidepressants (22.50% vs 14.16%), antipsychotics (4.68% vs 2.01%), opioid analgesics and narcotics (11.21% vs 9.09%), and benzodiazepines (7.60% vs 5.96%) (all, P<0.002). More patients with nonspecific chest pain received CVS drugs compared with the fall-coded group (69.13% vs 63.07%; P<0.002). Within the CVS category, more patients in the nonspecific chest pain group received angiotensin-II receptor antagonists, angiotensin-converting enzyme inhibitors, beta-blockers, calcium channel blockers, vasodilators, diuretics, and antiarrhythmics (all, P<0.002). No differences were noted between groups in the MSS category, except for NSAIDs, which more patients in the nonspecific chest pain group used than in the fall-coded group (6.44% vs 5.63%; P<0.002).

CONCLUSION

In this study, subjects with a health care encounter for a fall (as indicated by diagnostic code) were prescribed significantly more CNS-category medications than subjects in the age- and sex-matched comparison group.