The aim of this prospective, non-randomised, observational study was to compare the incidence of delirium in two settings of care for elderly patients requiring hospital admission: the geriatric home hospitalisation service (GHHS) and the traditional geriatric hospital ward (GHW).
The GHHS and GHW in this study are affiliated to the Geriatric Care Unit of San Giovanni Battista Hospital, a University teaching and tertiary-care hospital. GHHS has been extensively described in previous papers and has proven as effective as traditional hospitalisation for selected patients with acute pathologies (Aimonino Ricauda et al. 2004
). GHHS provides substitutive hospital-at-home care in a “clinical unit” model. The care is delivered by a multidisciplinary team consisting of three geriatricians, 13 nurses, two physiotherapists, one social worker and one counsellor. The team operates 7 days a week and looks after 25 patients a day on average. Every year, a mean of 450 patients is treated at home. About 60% of our patients are referred from the ED, 25% from hospital wards and 15% from specialists or general practitioners in the community. Medical consultation with other hospital specialists is possible in the hospital or at the patient’s home. From an administrative, legal, and financial standpoint, hospital-at-home patients are considered hospital inpatients until discharge.
Community dwelling patients, aged 75 years or older, consecutively admitted from the ED to GHHS or GHW from February through April 2007, were considered eligible. Six-month post-discharge follow-up interviews were completed in October 2007.
Inclusion criteria were: absence of probable or definite delirium at enrolment, according to CAM (Inouye et al. 1990
), and intermediate or high risk for delirium, according to the criteria of Inouye. The risk model created by Inouye and colleagues is based on four risk factors—vision impairment, severe illness, pre-existing cognitive impairment, and dehydration—and includes three levels of risk: low-risk (no risk factors present), intermediate-risk (1 to 2 factors present), high-risk (3 to 4 factors present) (Inouye et al. 1993
Exclusion criteria were: absence of a caregiver, inability to undergo interviewing, severe dementia that made administration of “Mini Mental State Examination” (MMSE) unfeasible, coma, aphasia or intubation, presence of a terminal illness (expected survival time < 6 months).
The primary outcomes in the two settings of care were mortality and incidence of delirium among acutely ill elderly patients, nursing home placement, hospital readmissions and mortality at 6 months after discharge. Secondary outcomes were: psychoactive drug use, complications, caregiver’s stress, cost analyses.
Functional and cognitive status 6 months after discharge in the delirious patients were considered as a secondary outcomes.
All enrolled patients were first assessed in the ED with a baseline standard clinical evaluation: blood tests, 12-lead electrocardiography, chest radiograms. Further investigations were performed according to the clinical judgment of the ED physician. After ED evaluation, patients were transferred either home or to the GHW.
The physician interviewers, who had at least 5 years experience in conducting research-related interviews in the elderly, were unaware of the objectives of the study and who had no role in the intervention, conducted the investigation, which consisted of: medical history, demographic and socio-economic characteristics, reason for hospital admission, severity of illness (Acute Physiology And Chronic Health Evaluation—APACHE II; Knaus et al. 1985
), co-morbidity (Cumulative Illness Rating Scale—CIRS; Conwell et al. 1993
), sight and hearing problems (graded from 0
normal to 3
serious impairment), functional status (Activities of Daily Living—DL, Instrumental Activities of Daily Living—IADL; Katz et al. 1963
; Lawton and Brody 1969
), cognitive status (MMSE; Folstein et al. 1975
), nutritional status (Mini Nutritional Assessment—MNA; Guigoz et al. 1996
), quality of life (Nottingham Health Profile—NHP; Hunt et al. 1985
), and affective condition (Geriatric Depression Scale—GDS; Yesavage et al. 1982
). Drugs used by patients prior to hospitalisation were recorded, especially medications bearing high risk for delirium, including benzodiazepines, anti-cholinergics, antidepressants and anti-Parkinsonians. Predisposing factors for delirium (age > 65 years, male gender, depression, previous history of delirium, protracted immobilisation, previous falls, recent trauma or bone fracture, vision or hearing loss, malnutrition, drinking habit, use of more than five drugs, use of psychotropic drugs, terminal illnesses) were also described.
For each patient, cognitive status (MMSE) and possible onset of acute delirium (CAM) were evaluated by physicians interviewers every 48 h or earlier, if patients were recognised as being confused, until discharge or death. Whenever an episode of delirium occurred, a standardised pre-coded form, describing duration and severity of delirium (Delirium Rating Scale—DRS; Trzepacz et al. 1988
), possible triggers, non-pharmacological and pharmacological treatments, was filled out.
Non-pharmacological treatment strategies to prevent and treat delirium were adopted in both care settings: reorientation techniques (board with names of care-team members calendars, clocks...), environmental modifications to prevent cognitive deprivation (discussion of current events, word games and other cognitively stimulating activities twice daily), daily mobilisation to avert immobilisation (at least three times daily), prevention of sleep deprivation (warm drinks, relaxation tapes, back massage, unit-wide noise-reduction strategies, scheduling of medications and procedures to avoid interrupting sleep of patients), prevention of malnutrition and dehydration (encouragement of oral intake of food and fluids, cleaning of the oral cavity, maintenance of food habits, frequent administration of small meals and fluid, patients socialisation during meals, and nutritional education for patients or their proxy).
Caregiver’s characteristics and level of stress at baseline, at time of discharge and 6 months after discharge (Relatives’ Stress Scale—RRS; Greene et al. 1982
) were also recorded.
Length of hospital stay and location of patient (home or nursing home) were recorded on discharge. Mortality, institutionalisation, hospital readmissions, functional, cognitive and depressive status in delirious patients were assessed by patient and caregiver interviews and by review of medical records 6 months after discharge. Finally, GHHS and GHW costs of care were compared.
Consent to participate was approved by the Ethical Committee of the University Hospital of Turin. It was administered to the patient or to a proxy in the ED by a physician before the patient was admitted to the GHW or to the GHHS and included information about the methods and the aims of the present study.
Data are presented as means ± SD (95% confidence intervals; CI) or as percentages in the corresponding categories. We used paired and unpaired t-tests to compare data within and between the groups, respectively, for parametric data, and X2 tests for non-parametric data. The Kaplan-Meier method was used to evaluate cumulative proportion survival at 6-month follow-up. The log-rank test was used to compare the survival curves among the patients with and without delirium. Survival time was defined as length of time between date of discharge and date of the follow-up study interview at 6 months or (in the case of death) the date of death.
Results were interpreted using the real probability. A P
0.05 was considered significant. For nonparametric tests, the real probability was interpreted using CI. Data were analysed with SPSS for Windows version 11.5.
Costs of patient management were calculated by comparing the direct health costs of GHHS interventions with those of GHW care. The costs were calculated in Euros and converted to United States dollars using an exchange rate of 1 Euro
$ 1.546. The daily GHHS costs included costs for geriatricians, nurses, counsellors, dietitians, and social workers, calculated according to the amount of time spent with patients and including a cost for noncontact time. Data on hospital costs were collected from the official hospital medical cost database, including direct medical costs for beds, staff, examinations, medications, rehabilitation, and miscellaneous expenses. Data on costs for hospital-at-home patients were obtained in a similar manner, except that costs for hospital-at-home patients did not include costs for food, laundry, heating, or lighting. Costs for ED care were included for both patient groups.