Agreement on dementia severity levels between the 8‐item and 21‐item Dementia Assessment Sheet for Community‐based Integrated Care System

Abstract

As older adults with dementia possess a higher risk of in-hospital adverse events, assessing the presence and severity of dementia in older inpatients on admission can contribute to the optimization of care. The Dementia Assessment Sheet for Community-based Integrated Care System 21-items (DASC-21) was developed in Japan to detect dementia and assess its severity among community-dwelling older adults by evaluating impairments in daily living and/or cognitive function. DASC-21 was also reported to be a practical assessment tool for identifying inpatients with a high risk of early readmission. An 8-item version (DASC8) of this tool was developed to assess impairments in daily living and cognitive function in order to determine the appropriate glycemic targets for older adults with diabetes. DASC-8 has also been applied to frailty screenings and comprehensive geriatric assessments in outpatient care. Although DASC-8 was developed based on DASC-21, these tools employ different definitions of the presence and severity of impairments in daily living and cognitive function. DASC-21 determines the risk of dementia and classifies patients into the following four categories as specified in the DASC-21 assessment manual: no dementia, low-level dementia, medium-level dementia, and serious-level dementia. In contrast, DASC-8 classifies patients into the following three categories: Category I: no functional impairment of daily living and no cognitive impairment; Category II: mild cognitive impairment (MCI) or instrumental activities of daily living impairment and no basic activities of daily living (BADL) impairment; and Category III: moderate or severe dementia and BADL impairment. Because DASC-8 is easier to use than DASC-21, ascertaining the agreement on dementia risk and severity between these tools may support clinical assessments of dementia among older inpatients on admission. We examined the agreement on dementia classifications between DASC-8 and DASC-21. This retrospective cross-sectional study was conducted using DASC-21 data from a general acute-care hospital in Tokyo, Japan. The sample included patients aged ≥65 years who were admitted to the subject hospital between July 11, 2016 and December 3, 2018. DASC-21 was administered to each patient, family member, or caregiver to assess the patient’s impairments in daily living and cognitive function during the month before admission. If patients did not have any family member or caregiver available, they completed the DASC-21 themselves or through a proxy. Based on the DASC-21 data, we also categorized the patients according to the DASC-8 classification criteria. The study protocol was approved by the Tokyo Metropolitan Institute of Gerontology Ethics Committee (Approval No. R18-20). We first identified 31 110 patients who were admitted to the subject hospital during the study period. We excluded 6745 patients with missing DASC-21 data, 321 patients aged <65 years, and 483 patients with DASC-21 completed by unrecorded persons. The first hospitalization episodes were analyzed for 10 771 patients who were admitted to this hospital multiple times during the study period. The final sample for this analysis comprised 12 790 patients (mean age: 80.0 years, standard deviation: 7.7). Approximately 56.4% of the patients were women, 94.2% were admitted from home, 66.4% had planned admissions, and 40.8% answered the DASC-21 by themselves. A total of 4665 patients (36%) were identified as having a risk of dementia based on DASC-21. Table 1 shows the agreement between the DASC-8 categorization of functional impairment of daily living and cognitive impairment and the DASC-21 classification of dementia severity. Almost all patients in DASC-8ʼs Category I were classified as having “no dementia” by DASC-21, and 89.4% of patients in Category III were classified as having “mediumor serious-level dementia”; however, only 38.4% of patients in Category II were classified as having “low-level dementia”. In examining the presence of functional impairment of daily living and cognitive