Excessive polypharmacy and potentially inappropriate prescribing in 147 care homes: a cross-sectional study.

BACKGROUND: Care home residents often have multiple cognitive and physical impairments, and are at high risk of adverse drug events (ADEs). AIM: To describe excessive polypharmacy and potentially inappropriate prescribing predisposing care home residents to ADEs. DESIGN & SETTING: A cross-sectional analysis of all dispensed prescriptions for 147 care home residents in Tayside and Fife, Scotland. METHOD: Prevalence of excessive polypharmacy was examined using multilevel logistic regression, by modelling associations between individual and care home predictors with excessive polypharmacy (≥10 drugs). Prescribing of drugs known to increase the risk of eight clinically important ADE categories was examined. Drugs prescribed within each ADE category, for each resident, were counted. RESULTS: In total, 32.3% (n = 1444/4468) of residents had excessive polypharmacy, which was more common in residents aged 70-74 years (adjusted odds ratio [aOR] 1.86, 95% confidence interval [CI] = 1.04 to 3.34) and 80-84 years (aOR 1.75, 95% CI = 1.01 to 3.02), living in a residential care home (aOR 1.50, 95% CI = 1.19 to 1.88), and located in Fife (aOR 1.37, 95% CI = 1.09 to 1.71). Excessive polypharmacy was less common in residents with dementia (aOR 0.73, 95% CI = 0.64 to 0.84), and 8.9% (95% CI = 5.9% to 11.6%) of the variation was attributable to care home predictors. Potentially inappropriate prescribing of ≥2 drugs was seen across all ADE categories, with highest prevalence seen in drugs predisposing to constipation (35.8%), sedation (27.7%), and renal injury (18.0%). CONCLUSION: Excessive polypharmacy is common in care home residents and is associated with both individual and care home predictors. Potentially inappropriate prescribing of drugs that predisposed residents to all included ADE categories is common. Research is needed to support and evaluate safe care home prescribing practices.

Impact of electronic alerts for acute kidney injury on patient outcomes: interrupted time-series analysis of population cohort data.

BACKGROUND: Automated acute kidney injury (AKI) electronic alerts (e-alerts) are rule-based warnings triggered by changes in creatinine and are intended to facilitate earlier detection in AKI. We assessed the impact of the introduction in the Tayside region of UK in April 2015 of automated AKI e-alerts with an accompanying education programme. METHODS: Interrupted time-series analysis using segmented regression was performed involving all adults with AKI aged ≥18 years who had a serum creatinine measured between 1 April 2013 and 31 March 2017. Analysis evaluated associations of AKI e-alert introduction on rate and severity (Stages 2-3) of AKI as well as mortality and occupied hospital bed days per patient per month in the population with AKI. RESULTS: There were 32 320 episodes of AKI during the observation period. Implementation of e-alerts had no effect on the rate of any AKI [incidence rate ratio (IRR) 0.996, 95% confidence interval (CI) 0.991 to 1.001, P = 0.086] or on the rate of severe AKI (IRR 0.995, 95% CI 0.990 to 1.000, P = 0.061). Subgroup analysis found no impact on the rate or severity of AKI in hospital or in the community. Thirty-day mortality following AKI did not improve (IRR 0.998, 95% CI 0.987 to 1.009, P = 0.688). There was a slight reduction in occupied bed days (ß-coefficient -0.059, 95% CI -0.094 to -0.025, P = 0.002). CONCLUSIONS: Introduction of automated AKI e-alerts was not associated with a change in the rate, severity or mortality associated with AKI, but there was a small reduction in occupied hospital bed days.

Effect of multiple episodes of acute kidney injury on mortality: an observational study.

BACKGROUND: Patients who survive an episode of acute kidney injury (AKI) are more likely to have further episodes of AKI. AKI is associated with increased mortality, with a further increase with recurrent episodes. It is not clear whether this is due to AKI or as a result of other patient characteristics. The aim of this study was to establish whether recurrence of AKI is an independent risk factor for mortality or if excess mortality is explained by other factors. METHODS: This observational cohort study included adult people from the Tayside region of Scotland, with an episode of AKI between 1 January 2009 and 31 December 2009. AKI was defined using the creatinine-based Kidney Disease: Improving Global Outcomes definition. Associations between recurrent AKI and mortality were examined using a Cox proportional hazards model. RESULTS: Survival was worse in the group identified to have recurrent AKI compared with those with a single episode of AKI [hazard ratio = 1.49, 95% confidence interval (CI) 1.37-1.63; P < 0.001]. After adjustment for comorbidities, stage of reference AKI, sex, age, medicines that predispose to renal impairment or, in the 3 months prior to the reference AKI, deprivation and baseline estimated glomerular filtration rate (eGFR), recurrent AKI was independently associated with an increase in mortality (hazard ratio = 1.25, 95% CI 1.14-1.37; P < 0.001). Increasing stage of reference AKI, age, deprivation, baseline eGFR, male sex, previous myocardial infarction, cerebrovascular disease and diuretic use were all associated with an increased risk of mortality in patients with recurrent AKI. CONCLUSIONS: Recurrent AKI is associated with increased mortality. After adjusting for patient characteristics, the increase in mortality is independently associated with recurrent AKI and is not solely explained by other risk factors.

The burden of psychotropic and anticholinergic medicines use in care homes: population-based analysis in 147 care homes.

BACKGROUND: older people living in care-homes are particularly vulnerable to adverse effects of psychotropic and anticholinergic drugs. METHODS: anonymised dispensed prescription data from all 4,478 residents aged ≥ 60 years in 147 care-homes in two Scottish health boards were analysed. Psychotropic medicines examined were antipsychotics, antidepressants, hypnotic/anxiolytics, opioids and gabapentinoids. Anticholinergic burden was measured using the modified anticholinergic risk scale (mARS). Variation between care-homes and associations with individual and care-home characteristics were examined using multilevel logistic regression. RESULTS: 63.5% of residents were prescribed at least one psychotropic drug, and 27.0% two or more, most commonly antidepressants (41.6%), opioids (20.3%), hypnotic/anxiolytics (16.9%) and antipsychotics (16.7%). 48.1% were prescribed an anticholinergic drug, and 12.1% had high anticholinergic burden (mARS ≥ 3). Variation between care-homes was high for antipsychotics (intra-cluster correlation coefficient [ICC] 8.2%) and hypnotics/anxiolytics (ICC = 7.3%), and moderate for antidepressants (ICC = 4.7%) and anticholinergics (ICC = 2.8%). Prescribing of all drugs was lower in the oldest old. People with dementia were more likely to be prescribed antipsychotics (adjusted OR = 1.45, 95%CI 1.23-1.71) but less likely to be prescribed anticholinergics (aOR = 0.61, 95%CI 0.51-0.74). Prescribing of antipsychotics was higher in Tayside (aOR = 1.52, 95%CI 1.20-1.92), whereas prescribing of antidepressants (particularly tricyclic-related) was lower (aOR = 0.66, 95%CI 0.56-0.79). There was no association with care-home regulator quality scores. CONCLUSION: care-home residents have high psychotropic and anticholinergic burden, with considerable variation between care-homes that is not related to existing measures of quality of care. Research to better understand variation between care-homes and the interaction with local prescribing cultures is needed.

Development and external validation of an acute kidney injury risk score for use in the general population.

BACKGROUND: Improving recognition of patients at increased risk of acute kidney injury (AKI) in the community may facilitate earlier detection and implementation of proactive prevention measures that mitigate the impact of AKI. The aim of this study was to develop and externally validate a practical risk score to predict the risk of AKI in either hospital or community settings using routinely collected data. METHODS: Routinely collected linked datasets from Tayside, Scotland, were used to develop the risk score and datasets from Kent in the UK and Alberta in Canada were used to externally validate it. AKI was defined using the Kidney Disease: Improving Global Outcomes serum creatinine-based criteria. Multivariable logistic regression analysis was performed with occurrence of AKI within 1 year as the dependent variable. Model performance was determined by assessing discrimination (C-statistic) and calibration. RESULTS: The risk score was developed in 273 450 patients from the Tayside region of Scotland and externally validated into two populations: 218 091 individuals from Kent, UK and 1 173 607 individuals from Alberta, Canada. Four variables were independent predictors for AKI by logistic regression: older age, lower baseline estimated glomerular filtration rate, diabetes and heart failure. A risk score including these four variables had good predictive performance, with a C-statistic of 0.80 [95% confidence interval (CI) 0.80-0.81] in the development cohort and 0.71 (95% CI 0.70-0.72) in the Kent, UK external validation cohort and 0.76 (95% CI 0.75-0.76) in the Canadian validation cohort. CONCLUSION: We have devised and externally validated a simple risk score from routinely collected data that can aid both primary and secondary care physicians in identifying patients at high risk of AKI.

Quinine exposure and the risk of acute kidney injury: a population-based observational study of older people.

OBJECTIVES: to establish and quantify any observable association between the exposure to community prescriptions for quinine and acute kidney injury (AKI) events in a population of older adults. DESIGN: two observational studies using the same dataset, a retrospective longitudinal cohort study and a self-controlled case series (SCCS). SETTING: NHS health board in Scotland. PARTICIPANTS: older adults (60+ years) who received quinine prescriptions in Tayside, Scotland, between January 2004 and December 2015. The first study included 12,744 individuals. The SCCS cohort included 5,907 people with quinine exposure and more than or equal to one AKI event. MAIN OUTCOME MEASURED: in the first study, multivariable logistic regression was used to calculate odds ratios (ORs) for AKI comparing between episodes with and without recent quinine exposure after adjustment for demographics, comorbidities and concomitant medications. The SCCS study divided follow-up for each individual into periods 'on' and 'off' quinine, calculating incidence rate ratios (IRRs) for AKI adjusting for age. RESULTS: during the study period, 273,596 prescriptions for quinine were dispensed in Tayside. A total of 13,616 AKI events occurred during follow-up (crude incidence 12.5 per 100 person-years). In the first study, exposure to quinine before an episode of care was significantly associated with an increased probability of AKI (adjusted OR = 1.27, 95% confidence interval (CI) 1.21-1.33). In the SCCS study, exposure to quinine was associated with an increased relative incidence of AKI compared to unexposed periods (IRR = 1.20, 95% CI 1.15-1.26), with the greatest risk observed within 30 days following quinine initiation (IRR = 1.48, 95% CI 1.35-1.61). CONCLUSION: community prescriptions for quinine in an older adult population are associated with an increased risk of AKI.

Assessing the accuracy of ICD-10 coding for measuring rates of and mortality from acute kidney injury and the impact of electronic alerts: an observational cohort study.

BACKGROUND: The application of a uniform definition for acute kidney injury (AKI) is vital to advance understanding and management of AKI. International Classification of Diseases (Tenth Revision) (ICD-10) coding is frequently used to define AKI, but its accuracy is unclear. The aim of this study was to determine whether ICD-10 coding is a reliable method of monitoring rates and outcomes of AKI in inpatients compared with biochemically defined AKI, and whether electronic alerts (e-alerts) for AKI affect ICD-10 AKI coding. METHODS: An observational cohort study of all 505 662 adult admissions to acute hospitals in two Scottish Health Boards [National Health Service (NHS) Tayside and NHS Fife] from January 2013 to April 2017 was performed. AKI e-alerts were implemented in NHS Tayside in April 2015. Sensitivity, specificity, positive and negative predictive values of ICD-10 coding for AKI compared with biochemically defined AKI using the Kidney Disease: Improving Global Outcomes definition and relative risk of 30-day mortality in people with ICD-10 and biochemically defined AKI before and after AKI e-alert implementation were performed. RESULTS: Sensitivity of ICD-10 coding for identifying biochemically defined AKI was very poor in both health boards for all AKI (Tayside 25.7% and Fife 35.8%) and for Stages 2 and 3 AKI (Tayside 43.8% and Fife 53.8%). Positive predictive value was poor both for all AKI (Tayside 76.1% and Fife 45.5%) and for Stages 2 and 3 AKI (Tayside 45.5% and Fife 36.8%). Measured mortality fell following implementation of AKI e-alerts in the ICD-10-coded population but not in the biochemically defined AKI population, reflecting an increase in the proportion of Stage 1 AKI in ICD-10-coded AKI. There was no evidence that the introduction of AKI e-alerts in Tayside improved ICD-10 coding of AKI. CONCLUSION: ICD-10 coding should not be used for monitoring of rates and outcomes of AKI for either research or improvement programmes.

Risk of acute kidney injury following community prescription of antibiotics: self-controlled case series.

BACKGROUND: Development of acute kidney injury (AKI) following the use of antibiotics such as sulphonamides, trimethoprim and aminoglycosides is a frequently described phenomenon. More recently, an association between fluoroquinolone use and AKI has been suggested. The aim of this study was to evaluate the risk of AKI as an unintended consequence of commonly prescribed antibiotics in a large community cohort using a method that fully adjusts for underlying patient characteristics, including potential unmeasured confounders. METHODS: A self-controlled case study was conducted and included all individuals aged 18 years and over in the Tayside region of Scotland who had a serum creatinine measured between 1 January 2004 and 31 December 2012. AKI episodes were defined using the Kidney Disease: Improving Global Outcomes definition. Data on oral community-prescribed antibiotics (penicillins, cephalosporins, fluoroquinolones, sulphonamides and trimethoprim, macrolides and nitrofurantoin) were collected for all individuals. Incidence rate ratios (IRRs) for AKI associated with antibiotic exposure versus time periods without antibiotic exposure were calculated. RESULTS: Combined use of sulphonamides, trimethoprim and nitrofurantoin rose by 47% and incidence of community-acquired AKI rose by 16% between 2008 and 2012. During the study period 12 777 individuals developed 14 900 episodes of AKI in the community, of which 68% was AKI Stage 1, 16% Stage 2 and 16% Stage 3. The IRR of AKI during any antibiotic use was 1.16 [95% confidence interval (CI) 1.10-1.23], and this was highest during sulphonamides or trimethoprim use; IRR 3.07 (95% CI 2.81-3.35). Fluoroquinolone and nitrofurantoin use was not associated with a significantly increased rate of AKI; IRR 1.13 (95% CI 0.94-1.35) and 1.16 (95% CI 0.91-1.50), respectively. CONCLUSIONS: Incidence of AKI rose by 16% between 2008 and 2012. In the same period the use of sulphonamides, trimethoprim and nitrofurantoin increased by 47%. A significant increased risk of AKI was seen with the use of sulphonamides and trimethoprim, but not with fluoroquinolones or nitrofurantoin.

Epidemiology and outcomes of people with dementia, delirium, and unspecified cognitive impairment in the general hospital: prospective cohort study of 10,014 admissions.

BACKGROUND: Cognitive impairment of various kinds is common in older people admitted to hospital, but previous research has usually focused on single conditions in highly-selected groups and has rarely examined associations with outcomes. This study examined prevalence and outcomes of cognitive impairment in a large unselected cohort of people aged 65+ with an emergency medical admission. METHODS: Between January 1, 2012, and June 30, 2013, admissions to a single general hospital acute medical unit aged 65+ underwent a structured specialist nurse assessment (n = 10,014). We defined 'cognitive spectrum disorder' (CSD) as any combination of delirium, known dementia, or Abbreviated Mental Test (AMT) score < 8/10. Routine data for length of stay (LOS), mortality, and readmission were linked to examine associations with outcomes. RESULTS: A CSD was present in 38.5% of all patients admitted aged over 65, and in more than half of those aged over 85. Overall, 16.7% of older people admitted had delirium alone, 7.9% delirium superimposed on known dementia, 9.4% known dementia alone, and 4.5% unspecified cognitive impairment (AMT score < 8/10, no delirium, no known dementia). Of those with known dementia, 45.8% had delirium superimposed. Outcomes were worse in those with CSD compared to those without - LOS 25.0 vs. 11.8 days, 30-day mortality 13.6% vs. 9.0%, 1-year mortality 40.0% vs. 26.0%, 1-year death or readmission 62.4% vs. 51.5% (all P < 0.01). There was relatively little difference by CSD type, although people with delirium superimposed on dementia had the longest LOS, and people with dementia the worst mortality at 1 year. CONCLUSIONS: CSD is common in older inpatients and associated with considerably worse outcomes, with little variation between different types of CSD. Healthcare systems should systematically identify and develop care pathways for older people with CSD admitted as medical emergencies, and avoid only focusing on condition-specific pathways such as those for dementia or delirium alone.