Measuring case-mix and outcome for older people in acute hospital care across Europe: the development and potential of the ACMEplus instrument

Aim: To identify case-mix variables measured shortly after admission to be included in a patient classification system (ACMEplus) that best explains hospital outcome for older people in different health care systems.

Design: Observational prospective cohort study collecting patient factors (sociodemographics, functional, mental, clinical, administrative and perceived health) at different time assessments.

Methods: Multicentre study involving eight hospitals in six European countries (United Kingdom, Spain, Italy, Finland, Greece and Poland). It included consecutive patients aged 65 years or older admitted to hospital for acute medical problems. Main outcome measures: discharge status, hospital readmission, mortality and length of stay.

Results: Of the 1667 included patients (mean age 78.1 years; male gender 43.5) two-third had at least one Geriatric Giant (immobility, confusion, incontinence or falls) on admission or shortly after. The most frequently affected system was cardiovascular (29.2) and 31 of patients declared poor or very poor health. Mean length of stay was 17.9 days, 79 of patients were discharged to their usual residence; in-hospital and 1-month follow up mortality were 7.4 and 11.6, respectively. Physical function explained the highest variation (between 8 and 21), followed by cognitive status and number of Geriatric Giants, for almost all outcomes except readmission.

Conclusions: Factors other than diagnosis (physical function, cognition and presenting problems) are important in predicting key outcomes of acute hospital care for older people and are consistent across countries. Their inclusion in a standardized system of measurement may be a way of improving quality and equity of medical care in older people.