Predicting incident delirium diagnoses using data from primary-care electronic health records

Abstract

Importance risk factors for delirium in hospital inpatients are well established, but less is known about whether delirium occurring in the community or during an emergency admission to hospital care might be predicted from routine primary-care records. Objectives identify risk factors in primary-care electronic health records (PC-EHR) predictive of delirium occurring in the community or recorded in the initial episode in emergency hospitalisation. Test predictive performance against the cumulative frailty index. Design Stage 1: case-control; Stages 2 and 3: retrospective cohort. Setting clinical practice research datalink: PC-EHR linked to hospital discharge data from England. Subjects Stage 1: 17,286 patients with delirium aged ≥60 years plus 85,607 controls. Stages 2 and 3: patients ≥ 60 years (n = 429,548 in 2015), split into calibration and validation groups. Methods Stage 1: logistic regression to identify associations of 110 candidate risk measures with delirium. Stage 2: calibrating risk factor weights. Stage 3: validation in independent sample using area under the curve (AUC) receiver operating characteristic. Results fifty-five risk factors were predictive, in domains including: cognitive impairment or mental illness, psychoactive drugs, frailty, infection, hyponatraemia and anticholinergic drugs. The derived model predicted 1-year incident delirium (AUC = 0.867, 0.852:0.881) and mortality (AUC = 0.846, 0.842:0.853), outperforming the frailty index (AUC = 0.761, 0.740:0.782). Individuals with the highest 10% of predicted delirium risk accounted for 55% of incident delirium over 1 year. Conclusions a risk factor model for delirium using data in PC-EHR performed well, identifying individuals at risk of new onsets of delirium. This model has potential for supporting preventive interventions.

The degree of frailty as a translational measure of health in aging

“…Indeed, a higher degree of frailty has been linked to a greater risk of disability in activities of daily living and falls 75,76 , delirium [77][78][79] , as well as more hospital admissions, with longer lengths of stay 75,80 , and more primary care visits-all leading to greater health care costs 73,81 . Work on the degree of frailty and risk extends to a variety of clinical settings, including critical care 5 , during invasive interventions 46 and in nursing homes 82 .…”

Delirium in COVID-19: epidemiology and clinical correlations in a large group of patients admitted to an academic hospital

“…Infections are frequently associated with delirium in older patients, especially if they imply alterations of physiological parameters and laboratory tests and are treated with the use of invasive devices [ 4 – 6 ]. These precipitating factors are common in patients hospitalized with pneumonia [ 7 ] and have also been observed in patients with moderate or severe COVID-19 [ 8 ].…”

Delirium: A Marker of Vulnerability in Older People

“…Cognitive impairment and dementia were also prominent risk factors for delirium in a systematic review on patients with hip fracture and in another systematic review on patients from Intensive Care Unit (ICU) (Oh et al, 2015;Zaal et al, 2015). Recently, a study by Bowman et al (2020) identified 55 risk factors that were predictive of delirium occurring in the community or recorded in emergency hospitalisation. These included cognitive impairment or mental illness, psychoactive drugs, frailty, infection, hyponatraemia and anticholinergic drugs (Bowman et al, 2020).…”

“…Recently, a study by Bowman et al (2020) identified 55 risk factors that were predictive of delirium occurring in the community or recorded in emergency hospitalisation. These included cognitive impairment or mental illness, psychoactive drugs, frailty, infection, hyponatraemia and anticholinergic drugs (Bowman et al, 2020). Recent studies are suggesting the SARS-CoV-2 infection may be a potential cause of delirium in older people admitted to hospital wards (Zaal et al, 2015).…”