Heat Waves, Drugs with Anticholinergic Effects, and Outcomes in Older Hospitalized Adults

Systematic review of the impact of heatwaves on health service demand in Australia

OBJECTIVES

Heatwaves have been linked to increased levels of health service demand in Australia. This systematic literature review aimed to explore health service demand during Australian heatwaves for hospital admissions, emergency department presentations, ambulance call-outs, and risk of mortality.

STUDY DESIGN

A systematic review to explore peer-reviewed heatwave literature published from 2000 to 2020.

DATA SOURCES

Articles were reviewed from six databases (MEDLINE, Scopus, Web of Science, PsychINFO, ProQuest, Science Direct). Search terms included: heatwave, extreme heat, ambulance, emergency department, and hospital. Studies were included if they explored heat for a period of two or more consecutive days. Studies were excluded if they did not define a threshold for extreme heat or if they explored data only from workers compensation claims and major events.

DATA SYNTHESIS

This review was prospectively registered with PROSPERO (# CRD42021227395 ). Forty-five papers were included in the final review following full-text screening. Following a quality assessment using the GRADE approach, data were extracted to a spreadsheet and compared. Significant increases in mortality, as well as hospital, emergency, and ambulance demand, were found across Australia during heatwave periods. Admissions for cardiovascular, renal, respiratory, mental and behavioural conditions exhibited increases during heatwaves. The most vulnerable groups during heatwaves were children (< 18 years) and the elderly (60+).

CONCLUSIONS

Heatwaves in Australia will continue to increase in duration and frequency due to the effects of climate change. Health planning is essential at the community, state, and federal levels to mitigate the impacts of heatwaves on health and health service delivery especially for vulnerable populations. However, understanding the true impact of heatwaves on health service demand is complicated by differing definitions and methodology in the literature. The Excess Heat Factor (EHF) is the preferred approach to defining heatwaves given its consideration of local climate variability and acclimatisation. Future research should explore evidence-based and spatially relevant heatwave prevention programs. An enhanced understanding of heatwave health impacts including service demand will inform the development of such programs which are necessary to promote population and health system resilience.

High anticholinergic burden at admission associated with in-hospital mortality in older patients: A comparison of 19 different anticholinergic burden scales

Although no gold standard exists to assess a patient's anticholinergic burden, a review identified 19 anticholinergic burden scales (ABSs). No study has yet evaluated whether a high anticholinergic burden measured with all 19 ABSs is associated with in‐hospital mortality and length of stay (LOS). We conducted a cohort study at a Swiss tertiary teaching hospital using patients' electronic health record data from 2015–2018. Included were patients aged ≥65 years, hospitalised ≥48 h without stays and >24 h in intensive care. Patients' cumulative anticholinergic burden score was classified using a binary (<3: low, ≥3: high) and categorical approach (0: no, 0.5–3: low, ≥3: high). In‐hospital mortality and LOS were analysed using multivariable logistic and linear regression, respectively. We included 27,092 patients (mean age 78.0 ± 7.5 years, median LOS 6 days). Of them, 913 died. Depending on the evaluated ABS, 1370 to 17,035 patients were exposed to anticholinergics. Patients with a high burden measured by all 19 ABSs were associated with a 1.32‐ to 3.03‐fold increase in in‐hospital mortality compared with those with no/low burden. We obtained similar results for LOS. To conclude, discontinuing drugs with anticholinergic properties (score ≥3) at admission might be a targeted intervention to decrease in‐hospital mortality and LOS.

Quality of anticholinergic burden scales and their impact on clinical outcomes: a systematic review

PURPOSE

Older people are at risk of anticholinergic side effects due to changes affecting drug elimination and higher sensitivity to drug's side effects. Anticholinergic burden scales (ABS) were developed to quantify the anticholinergic drug burden (ADB). We aim to identify all published ABS, to compare them systematically and to evaluate their associations with clinical outcomes.

METHODS

We conducted a literature search in MEDLINE and EMBASE to identify all published ABS and a Web of Science citation (WoS) analysis to track validation studies implying clinical outcomes. Quality of the ABS was assessed using an adapted AGREE II tool. For the validation studies, we used the Newcastle-Ottawa Scale and the Cochrane tool Rob2.0. The validation studies were categorized into six evidence levels based on the propositions of the Oxford Center for Evidence-Based Medicine with respect to their quality. At least two researchers independently performed screening and quality assessments.

RESULTS

Out of 1297 records, we identified 19 ABS and 104 validations studies. Despite differences in quality, all ABS were recommended for use. The anticholinergic cognitive burden (ACB) scale and the German anticholinergic burden scale (GABS) achieved the highest percentage in quality. Most ABS are validated, yet validation studies for newer scales are lacking. Only two studies compared eight ABS simultaneously. The four most investigated clinical outcomes delirium, cognition, mortality and falls showed contradicting results.

CONCLUSION

There is need for good quality validation studies comparing multiple scales to define the best scale and to conduct a meta-analysis for the assessment of their clinical impact.

Quality of anticholinergic burden scales and their impact on clinical outcomes: a systematic review

Purpose

Older people are at risk of anticholinergic side effects due to changes affecting drug elimination and higher sensitivity to drug’s side effects. Anticholinergic burden scales (ABS) were developed to quantify the anticholinergic drug burden (ADB). We aim to identify all published ABS, to compare them systematically and to evaluate their associations with clinical outcomes.

Methods

We conducted a literature search in MEDLINE and EMBASE to identify all published ABS and a Web of Science citation (WoS) analysis to track validation studies implying clinical outcomes. Quality of the ABS was assessed using an adapted AGREE II tool. For the validation studies, we used the Newcastle-Ottawa Scale and the Cochrane tool Rob2.0. The validation studies were categorized into six evidence levels based on the propositions of the Oxford Center for Evidence-Based Medicine with respect to their quality. At least two researchers independently performed screening and quality assessments.

Results

Out of 1297 records, we identified 19 ABS and 104 validations studies. Despite differences in quality, all ABS were recommended for use. The anticholinergic cognitive burden (ACB) scale and the German anticholinergic burden scale (GABS) achieved the highest percentage in quality. Most ABS are validated, yet validation studies for newer scales are lacking. Only two studies compared eight ABS simultaneously. The four most investigated clinical outcomes delirium, cognition, mortality and falls showed contradicting results.

Conclusion

There is need for good quality validation studies comparing multiple scales to define the best scale and to conduct a meta-analysis for the assessment of their clinical impact.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-02994-x) contains supplementary material, which is available to authorized users.

Is cognitive impairment associated with antipsychotic dose and anticholinergic equivalent loads in first-episode psychosis?

BACKGROUND

Cognitive deficits are a core feature of early stages in schizophrenia. However, the extent to which antipsychotic (AP) have a deleterious effect on cognitive performance remains under debate. We aim to investigate whether anticholinergic loadings and dose of AP drugs in first episode of psychosis (FEP) in advanced phase of remission are associated with cognitive impairment and the differences between premorbid intellectual quotient (IQ) subgroups.

METHODS

Two hundred and sixty-six patients participated. The primary outcomes were cognitive dimensions, dopaminergic/anticholinergic load of AP [in chlorpromazine equivalents (Eq-CPZ) and the Anticholinergic Risk Scale (ARS), respectively].

RESULTS

Impairments in processing speed, verbal memory and global cognition were significantly associated with high Eq-CPZ and verbal impairment with high ARS score. Moreover, this effect was higher in the low IQ subgroup.

CONCLUSIONS

Clinicians should be aware of the potential cognitive impairment associated with AP in advanced remission FEP, particularly in lower premorbid IQ patients.

Psychotropics, Environmental Temperature, and Hospital Outcomes in Older Medical Patients

PURPOSE

The authors investigated whether the use of psychotropics and environmental temperature on admission influence hospital length of stay (LOS) and mortality in older medical patients.

METHODS

Clinical and demographic characteristics, Charlson Comorbidity Index, use of psychotropic and nonpsychotropic drugs, hospital LOS, and mortality were retrospectively collected in medical patients 65 years and older (n = 382) admitted to a metropolitan teaching hospital during 5 consecutive heat waves (HWs) between 2007 and 2009. Patients admitted either before or after each HW, matched for HW period, age, and admission day of the week, served as controls (non-HW, n = 1339).

RESULTS

Total number of psychotropic and nonpsychotropic drugs, Charlson Comorbidity Index, comorbidities, number of daily admissions, LOS, and mortality were similar in the HW and non-HW groups. After adjusting for clinical and demographic confounders, competing risks regression showed that psychotropic use, particularly antipsychotics, predicted increased LOS during non-HW (subdistribution hazard ratio: 95% CI, 0.82, 0.72-0.94; P = 0.003) but not HW (subdistribution hazard ratio: 95% CI, 0.89, 0.69-1.14; P = 0.36) periods. The effect of psychotropics on LOS during normal weather conditions was particularly evident in the old-old subgroup (difference [SE] in coefficients between non-HW and HW periods: -0.52 [0.25], P = 0.036 in patients >80 years; 0.11 [0.19], P = 0.54, in patients 65-80 years). By contrast, psychotropics did not predict hospital mortality during non-HW or HW periods.

CONCLUSIONS

Psychotropic use on admission, particularly antipsychotics, predicted hospital LOS, but not mortality, in older medical patients, particularly those older than 80 years, during normal environmental temperature. However, there was no effect of psychotropics on LOS during extreme heat.

The effect of ambient temperature on type-2-diabetes: case-crossover analysis of 4+ million GP consultations across England

BACKGROUND

Given the double jeopardy of global increases in rates of obesity and climate change, it is increasingly important to recognise the dangers posed to diabetic patients during periods of extreme weather. We aimed to characterise the associations between ambient temperature and general medical practitioner consultations made by a cohort of type-2 diabetic patients. Evidence on the effects of temperature variation in the primary care setting is currently limited.

METHODS

Case-crossover analysis of 4,474,943 consultations in England during 2012-2014, linked to localised temperature at place of residence for each patient. Conditional logistic regression was used to assess associations between each temperature-related consultation and control days matched on day-of-week.

RESULTS

There was an increased odds of seeking medical consultation associated with high temperatures: Odds ratio (OR) = 1.097 (95% confidence interval = 1.041, 1.156) per 1 °C increase above 22 °C. Odds during low temperatures below 0 °C were also significantly raised: OR = 1.024 (1.019, 1.030). Heat-related consultations were particularly high among diabetics with cardiovascular comorbidities: OR = 1.171 (1.031, 1.331), but there was no heightened risk with renal failure or neuropathy comorbidities. Surprisingly, lower odds of heat-related consultation were associated with the use of diuretics, anticholinergics, antipsychotics or antidepressants compared to non-use, especially among those with cardiovascular comorbidities, although differences were not statistically significant.

CONCLUSIONS

Type-2 diabetic patients are at increased odds of medical consultation during days of temperature extremes, especially during hot weather. The common assumption that certain medication use heightens the risk of heat illness was not borne-out by our study on diabetics in a primary care setting and such advice may need to be reconsidered in heat protection plans.

Anticholinergic drug exposure is associated with delirium and postdischarge institutionalization in acutely ill hospitalized older patients

Several studies investigated the possible association between anticholinergic drugs and diverse clinical outcomes in older persons, but the results are inconsistent. The aim of this study was to investigate whether anticholinergic drug exposure is associated with delirium on admission, length of hospital stay, postdischarge institutionalization and in-hospital mortality in acutely ill hospitalized older patients. In this observational chart review study, we included acutely ill patients aged 65 and older who were admitted to the geriatric ward of the Erasmus University Medical Center, Rotterdam, The Netherlands, between 2012 and 2015 (n = 905). Anticholinergic drug exposure on admission was defined as the use of anticholinergic drugs, total number of anticholinergic drugs and anticholinergic drug burden score (ADB), quantified with the Anticholinergic Risk Scale (ARS), the Anticholinergic Cognitive Burden scale (ACB) and the list of Chew et al. (Chew). Logistic regression analyses were performed to investigate possible associations between anticholinergic drug exposure and the aforementioned outcomes. Analyses were adjusted for age, sex, comorbidities, non-anticholinergic drugs and delirium, where appropriate. Moderate and high ADB measured with the ARS were associated with delirium on admission with odds ratios (OR) of 1.70 (95% confidence interval (CI) = 1.16-2.49) and 1.83 (95% CI = 1.06-3.15), respectively. High ADB measured with the ARS was also associated with postdischarge institutionalization (OR = 2.43, 95% CI = 1.24-4.75). No associations were found using the ACB and Chew. Future studies are warranted to investigate the clinical usefulness of the ARS in reducing complications in older persons.