Author Affiliation: The University of Newcastle, Newcastle, and Wyong Hospital, Lake Haven, New South Wales, Australia.
Gross and colleagues1 wrote an interesting article on hospital admissions in patients with Alzheimer disease 65 years or older who visited the Massachusetts Alzheimer Disease Research Center (ADRC) at least 3 times. The key to their article is the accuracy of discharge coding for delirium in hospital medical charts.
The diagnosis of delirium is fraught with problems. In many hospitals clinicians label any elderly patient with acute confusion as delirious even if they do not meet criteria such as Confusion Assessment Method (used by physicians) or Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (used by psychiatrists). I decided to conduct a retrospective analysis in the Wyong Hospital Memory Clinic to replicate the Massachusetts ADRC study by Gross et al.1 Wyong Hospital has 370 beds and is located 100 km north of Sydney, Australia. Among the 473 patients in the Wyong Hospital Memory Clinic database, I selected 193 with dementia or mild cognitive impairment who had at least 1 hospital admission (Gross et al1 sampled only patients with dementia and not MCI). Total follow-up at Wyong Hospital was 340.3 patient-years; the median follow-up was 699 days, or 1.91 years, compared with the median follow-up of 3.2 years in Massachusetts.
Regal PJ. Delirium Admissions in Dementia. JAMA Intern Med. 2013;173(7):597. doi:10.1001/jamainternmed.2013.3303