Drug Prescriptions/statistics & numerical data

Identifying and quantifying potentially problematic prescribing cascades in clinical practice: A mixed-methods study

Author/s: 
Atiya K Mohammad, Jacqueline G Hugtenburg, Joost W Vanhommerig

Background: A prescribing cascade occurs when medication causes an adverse drug reaction (ADR) that leads to the prescription of additional medication. Prescribing cascades can cause excess medication burden, which is of particular concern in older adults. This study aims to identify and quantify potentially problematic prescribing cascades relevant for clinical practice.

Methods: A mixed-methods study was conducted. First, prescribing cascades were identified through literature search. An expert panel (n = 16) of pharmacists and physicians assessed whether these prescribing cascades were potentially problematic. Next, a cohort study quantified potentially problematic prescribing cascades in adults using Dutch community pharmacy data for the period 2015-2020. Additionally, the influence of multiple medications potentially causing the same ADR was evaluated. Prescription sequence symmetry analysis was used to calculate adjusted sequence ratios (aSRs), adjusting for temporal prescribing trends. An aSR >1.0 indicates the occurrence of a prescribing cascade. In a subgroup analysis, aSRs were calculated for older adults.

Results: Seventy-six prescribing cascades were identified in literature and three were provided by experts. Of these, 66 (83.5%) were considered potentially problematic. A significant positive aSR for the medication sequence was found for 41 (62.1%) of these prescribing cascades. The highest aSR was found for amiodarone potentially causing hypothyroidism treated with thyroid hormones (4.63 [95% confidence interval 4.40-4.85]), based on 565 incident users. The biggest population (n = 34,645) was found for angiotensin converting enzyme-inhibitors potentially causing urinary tract infections treated with antibiotics. Regarding four potential ADRs, the aSRs were higher for people using multiple medications that cause the same ADR as compared to people using only one of those medications. Among older adults the aSRs remained significant for 37 prescribing cascades.

Conclusion: An overview was generated of potentially problematic prescribing cascades relevant for clinical practice. These results can support healthcare providers to intervene and reduce medication burden for older adults.

Associations between gabapentinoids and suicidal behaviour, unintentional overdoses, injuries, road traffic incidents, and violent crime: population based cohort study in Sweden

Author/s: 
Molero, Y., Larsson H., D'Onofrio B.M., Sharp D.J., Fazel S.

Abstract

OBJECTIVE:

To examine associations between gabapentinoids and adverse outcomes related to coordination disturbances (head or body injuries, or both and road traffic incidents or offences), mental health (suicidal behaviour, unintentional overdoses), and criminality.

DESIGN:

Population based cohort study.

SETTING:

High quality prescription, patient, death, and crime registers, Sweden.

PARTICIPANTS:

191 973 people from the Swedish Prescribed Drug Register who collected prescriptions for gabapentinoids (pregabalin or gabapentin) during 2006 to 2013.

MAIN OUTCOME MEASURES:

Primary outcomes were suicidal behaviour, unintentional overdoses, head/body injuries, road traffic incidentsand offences, and arrests for violent crime. Stratified Cox proportional hazards regression was conducted comparing treatment periods with non-treatment periods within an individual. Participants served as their own control, thus accounting for time invariant factors (eg, genetic and historical factors), and reducing confounding by indication. Additional adjustments were made by age, sex, comorbidities, substance use, and use of other antiepileptics.

RESULTS:

During the study period, 10 026 (5.2%) participants were treated for suicidal behaviour or died from suicide, 17 144 (8.9%) experienced an unintentional overdose, 12 070 (6.3%) had a road traffic incident or offence, 70 522 (36.7%) presented with head/body injuries, and 7984 (4.1%) were arrested for a violent crime. In within-individual analyses, gabapentinoid treatment was associated with increased hazards of suicidal behaviour and deaths from suicide (age adjusted hazard ratio 1.26, 95% confidence interval 1.20 to 1.32), unintentional overdoses (1.24, 1.19 to 1.28), head/body injuries (1.22, 1.19 to 1.25), and road traffic incidents and offences (1.13, 1.06 to 1.20). Associations with arrests for violent crime were less clear (1.04, 0.98 to 1.11). When the drugs were examined separately, pregabalin was associated with increased hazards of all outcomes, whereas gabapentin was associated with decreased or no statistically significant hazards. When stratifying on age, increased hazards of all outcomes were associated with participants aged 15 to 24 years.

CONCLUSIONS:

This study suggests that gabapentinoids are associated with an increased risk of suicidal behaviour, unintentionaloverdoses, head/body injuries, and road traffic incidents and offences. Pregabalin was associated with higher hazards of these outcomes than gabapentin.

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Subscribe to Drug Prescriptions/statistics & numerical data