With respect to dementia in the general hospital setting, the term “prevalence” is often used in an undifferentiated form.
This may give the false impression that it always refers to the same measurement of frequency of illness, to which Stausberg and colleagues draw our attention. We have to differentiate between at least two frequency measurements: on the one hand, the average proportion of patients with dementia of all patients who are hospitalized on a reference date (point prevalence); and on the other hand, the proportion of patients with dementia of all patients treated (admission or period prevalence). The greater the differences between the length of stay of patients with and without dementia, the more these two measurements diverge from each other.
Stausberg and colleagues suspect that our prevalence rate of 18.4% might be based on a period prevalence of around 10% and recommend that we directly standardize against the length of stay for comparative purposes.
According to a recent review, most studies indeed suggest that length of stay is significantly longer for patients with dementia as a comorbidity (1). Whether that also applies to Germany is still unclear. The most extensive study to date, of insured persons in Saxony, showed no differences (2).
As our study was cross-sectional, we do not know the total length of stay of patients (3). However, the length of stay from hospital admission until the reference date survey did not differ for patients with or without dementia. In accordance with the analysis results from Saxony (2), we see this as an indication that the high point prevalence in Germany is mainly due to higher hospital admission rates of people with dementia, and not due to a longer length of stay per treatment episode.
On behalf of the authors
Dr. phil. Dipl.-Psych. Horst Bickel
Klinik und Poliklinik für Psychiatrie und Psychotherapie der TU München, Klinikum rechts der Isar
Conflict of interest statement
Dr. Bickel has been reimbursed for travel expenses, and has received study support (third-party funds), from the Robert Bosch Foundation.
|1.||Möllers T, Stocker H, Wie W, Perna L, Brenner H: Length of hospital stay and dementia: A systematic review of observational studies. Int J Geriatr Psychiatry 2019; 34: 8–21 CrossRef MEDLINE|
|2.||Motzek T, Werblow A, Schmitt J, Marquardt G: Administrative Prävalenz und Versorgungssituation der Demenz im Krankenhaus – Eine versorgungsepidemiologische Studie basierend auf GKV-Daten sächsischer Versicherter. Gesundheitswesen (efirst) 2018 CrossRef|
|3.||Bickel H, Hendlmeier I, Heßler JB, et al.: The prevalence of dementia and cognitive impairment in hospitals—results from the General Hospital Study (GHoSt). Dtsch Arztebl Int 2018; 115: 733–40 VOLLTEXT|