Inappropriate benzodiazepine use in older adults and the risk of fracture

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

• Benzodiazepine use increases the risk of fracture in the elderly.
• It is controversial which conditions of use are most risky, e.g. use of short- or long-acting benzodiazepines, dose and duration of use.
• The well-known Beers criteria include statements about inappropriate benzodiazepine use in elderly and the risk of fracture, but their clinical value has never been tested in an outcome study.

WHAT THIS STUDY ADDS

• Inappropriate benzodiazepine use according to the Beers criteria is not associated with an increased risk of fracture.
• Daily dose and duration of use is associated with higher risk of fracture, not the type of benzodiazepine prescribed as the Beers criteria state.

AIMS

The Beers criteria for prescribing in elderly are well known and used for many drug utilization studies. We investigated the clinical value of the Beers criteria for benzodiazepine use, notably the association between inappropriate use and risk of fracture.

METHODS

We performed a nested case–control study within the Rotterdam Study, a population-based cohort study in 7983 elderly. The proportion of ‘inappropriate’ benzodiazepine use according to the Beers criteria was compared between fracture patients and controls. ‘Inappropriate’ use for elderly implies use of some long-acting benzodiazepines and some intermediate/short-acting ones exceeding a suggested maximum daily dose. Also, alternative criteria were applied to compare the risk of fracture. Cases were defined as persons with incident fracture between 1991 and 2002 who were current benzodiazepine users on the fracture date. Controls were matched on fracture date and were also current benzodiazepine users.

RESULTS

The risk of fracture in ‘inappropriate’ benzodiazepine users according to the Beers criteria was not significantly different from ‘appropriate’ users [odds ratio (OR) 1.07, 95% confidence interval (CI) 0.72, 1.60]. However, a significantly higher risk of fracture was found in ‘high dose’ users and a longer duration of use (14–90 days), irrespective of the type of benzodiazepine (OR 3.45, 95% CI 1.38, 8.59).

CONCLUSIONS

These findings suggest that inappropriate benzodiazepine use according to the Beers criteria is not associated with increased risk of fracture. Daily dose and longer duration of use (>14 days) is associated with higher risk of fracture, irrespective of the type of benzodiazepine prescribed.     

Potentially inappropriate medications in geriatric outpatients with polypharmacy: application of six sets of published explicit criteria

AIM

Our aim was to compare the practicability of six different potentially inappropriate medication (PIM) criteria in geriatric outpatients with polypharmacy.

METHODS

We analysed baseline data from the Medication Safety Review Clinic in Taiwanese Elders (MSRC-Taiwan) study. The prevalence and correlates of PIMs were determined on the basis of criteria developed in the USA, Canada, France, Norway, Ireland and Thailand. The percentage of PIMs considered as drug-related problems and the problem-solving rate are reported.

RESULTS

In the 193 participants, the prevalence of PIM varied from 24 to 73%. Application of the criteria revealed that a high number of chronic medications was a common risk factor for having at least one PIM. Of the 1713 medications reviewed, 5.6–14.8% were considered PIMs. Only 30–40% of the identified PIMs were reported as drug-related problems by the MSRC team experts. Criteria with a higher number of statements and a higher percentage of local market/institution drug availability tended to detect more PIMs.

CONCLUSIONS

The prevalence of PIM varied significantly when different criteria were applied. Caution should be exercised in applying PIM criteria developed in other regions when medication availability in the local market is limited.     

Application of the Beers Criteria to Alternate Level of Care Patients in Hospital Inpatient Units

Background:

The Beers criteria were developed to help in identifying potentially inappropriate medications (PIMs) for elderly patients. These medications are often associated with adverse events and limited effectiveness in older adults. Patients awaiting an alternate level of care (ALC patients) are those who no longer require acute care hospital services and are waiting for placement elsewhere. They are often elderly, have complex medication regimens, and are at high risk of adverse events. At the time of this study no studies had applied the Beers criteria to ALC patients in Canadian hospitals.

Objectives:

To determine the proportion of ALC patients receiving PIMs and the proportion experiencing selected PIM-related adverse events.

Methods:

A retrospective chart review of ALC patients 65 years of age or older was performed to identify PIMs and the occurrence of selected adverse events (specifically central nervous system [CNS] events, falls, bradycardia, hypoglycemia, seizures, insomnia, gastrointestinal bleeding, and urinary tract infections). A logistic regression model with a random intercept for each patient was constructed to estimate odds ratios and probabilities of adverse events.

Results:

Fifty-two ALC patients were included in the study. Of these, 48 (92%) were taking a PIM. Of the 922 adverse events evaluated, 407 (44.1%) were associated with a regularly scheduled PIM. Among patients who were taking regularly scheduled PIMs, there was a significantly increased probability of an adverse CNS event and of a fall (p < 0.001 for both). The most common PIM medication classes were first-generation antihistamines (24 [46%] of the 52 patients), antipsychotics (21 patients [40%]), short-acting benzodiazepines (15 patients [29%]), and nonbenzodiazepine hypnotics (14 patients [27%]).

Conclusions:

A high proportion of ALC patients were taking PIMs and experienced an adverse event that may have been related to these drugs. These findings suggest that the ALC population might benefit from regular medication review and monitoring to prevent or detect adverse events.     

Prevalence of potentially hazardous drug interactions amongst Australian veterans

BACKGROUND

Up to 21% of adverse drug event-related hospital admissions are due to drug interactions. Clinical significance of drug interactions varies, and drug interactions defined ‘potentially hazardous’ are more likely to contribute to morbidity and mortality.

AIM

The aim of this study was to assess the prevalence of potentially hazardous drug interactions in an elderly Australian veteran population.

METHODS

This study assessed the prevalence of potentially hazardous drug interactions, where hazardous was defined in three or more international drug interaction references, using Repatriation Pharmaceutical Benefits Scheme pharmacy claims data. Analysis was limited to patients who received regular concurrent dispensings of potentially hazardous interacting medicines.

RESULTS

Of the 287 074 subjects included in the study, 1.5% were dispensed potentially hazardous interacting drug pairs. For patients dispensed cyclosporin, concomitant use of a statin was common (47%); as was statin use with those dispensed itraconazole (31%). Of those dispensed methotrexate, 24% also received a non-steroidal anti-inflammatory drug; of those on lithium, 18% also received an ACE inhibitor or angiotensin 2 receptor blocker; of those on warfarin, 7.2% and 5.9% were co-dispensed an non-steroidal anti-inflammatory drugs or antiplatelets respectively; for those on verapamil, 5.3% were co-dispensed a beta-blocker, while for those on amiodarone 6.2% were co-dispensed digoxin.

CONCLUSIONS

Overall prevalence of potentially serious drug interactions appears to be low in the Australian veteran population. However, patients taking cyclosporine, itraconazole, methotrexate, lithium, warfarin, verapamil and amiodarone appear to be most at risk and their medicine use should be regularly reviewed to prevent potentially hazardous drug interactions.     

Influence of Admission to a Tertiary Care Hospital after a Fall on Use of Potentially Inappropriate Medications among Older Patients

Background:

Each year, about one-third of individuals over the age of 65 years will experience a fall, and half of these will experience a subsequent fall in the following year. The use of potentially inappropriate medications (PIMs) is an important factor contributing to increased fall risk in geriatric patients.

Objective:

To determine the proportion of patients over the age of 65 admitted to orthopedics and general medicine services with diagnosis of a fall who experienced a change in the total number or dosage of PIMs, as defined by the Beers criteria, upon discharge from hospital.

Methods:

This retrospective observational study involved patients admitted to a tertiary care hospital with diagnosis of a fall between January 1 and December 31, 2011. Those aged 65 years or older with at least one PIM on admission were eligible for inclusion. Data analysis included χ² and Fisher testing, as well as multivariate analysis.

Results:

A total of 148 patients were included, of whom 63 (43%) had an overall change in the dosage or number of PIMs during their hospital stay. Forty patients (27%) had an overall reduction in the dosage or number of PIMs upon discharge from hospital, whereas 23 (16%) experienced an overall increase in the dosage or total number of PIMs. The mean number (± standard deviation) of PIMs decreased during the hospital stay, from 1.6 ± 0.8 on admission to 1.4 ± 0.9 on discharge (p = 0.03). Benzodiazepines were the class of PIMs most frequently discontinued or reduced in dosage.

Conclusion:

One-quarter of patients admitted with falls had de-escalation of PIMs upon hospital discharge. Although dosage reduction or drug discontinuation may not be appropriate for all patients, a standardized approach to medication review during the hospital stay and improved prescriber education and awareness of PIM use among elderly individuals are warranted.     

Quality use of medicines and health outcomes among a cohort of community dwelling older men: an observational study

AIM

To determine the prevalence of potentially suboptimal medication use and association with adverse outcomes.

METHODS

A prospective, observational cohort study of 4260 community-dwelling older men from Perth, Western Australia (mean age of 77 ± 3.6 years) was conducted. Follow-up was for 4.5 years (or until death, if sooner). Cox proportional hazard models were used to explore associations between suboptimal medication use and prospective clinical outcomes. Logistic regression analyses were used to explore predictors of a fall in the previous 12 months.

RESULTS

Use of potentially inappropriate medicines (48.7%), polypharmacy (≥5 medications, 35.8%) and potential under-utilization (56.7%) were highly prevalent, and overall 82.3% of participants reported some form of potentially suboptimal medication use. A self-reported history of falls in the previous 12 months was independently associated with the number of medicines taken (odds ratio [OR]= 1.06, 95% confidence interval [CI] 1.02, 1.09) and use of one or more potentially inappropriate medicines (OR = 1.23, 95% CI 1.04, 1.45). After adjusting for age, co-morbidity, smoking status, body mass index, hypertension and educational attainment, the number of medicines reported was associated with admission to hospital (hazard ratio [HR]= 1.04, 95% CI 1.03, 1.06), cardiovascular events (HR = 1.09, 95% CI 1.06, 1.12) and all cause mortality (HR = 1.04, 95% CI 1.00, 1.07). Use of one or more potentially inappropriate medicines was associated with admission to hospital (HR = 1.16, 95% CI 1.08, 1.24). Potential under-utilization was associated with cardiovascular events (HR = 1.20, 95% CI 1.03, 1.40).

CONCLUSIONS

These data suggest that both medication over-use and under-use occur frequently among older men and may be harmful.     

Doctors’ perspectives on the barriers to appropriate prescribing in older hospitalized patients: a qualitative study

Aims

Older patients commonly suffer from multimorbidites and take multiple medications. As a result, these patients are more vulnerable to potentially inappropriate prescribing (PIP). PIP in older patients may result in adverse drug events (ADEs) and hospitalizations. However, little has been done to identify why PIP occurs. The objectives of this study were (i) to identify hospital doctors'' perceptions as to why PIP occurs, (ii) to identify the barriers to addressing the issues identified and (iii) to determine which intervention types would be best suited to improving prescribing.

Methods

Semi-structured interviews based on the Theoretical Domains Framework (TDF), a tool used to apply behaviour change theories, were conducted with 22 hospital doctors. Content analysis was conducted to identify domains of the TDF that could be targeted to improve prescribing for older people. These domains were then mapped to the behaviour change wheel to identify possible intervention types.

Results

Content analysis identified five of the 12 domains in the TDF as relevant: (i) environmental context and resources, (ii) knowledge, (iii) skills, (iv) social influences and (v) memory/attention and decision processes. Using the behaviour change wheel, the types of interventions deemed suitable were those based on training and environmental restructuring.

Conclusion

This study shows that doctors feel there is insufficient emphasis on geriatric pharmacotherapy in their undergraduate/postgraduate training. An intervention providing supplementary training, with particular emphasis on decision processes and dealing with social influences would be justified. This study has, however, uncovered many areas for potential intervention in the future.