Individuals with Cognitive Impairment Entering Long-Term Care: Characteristics and Cumulative Incidence of Dementia after Care Entry

Abstract

Objectives

To characterize individuals entering long-term care facilities (LTCFs) with evidence of cognitive impairment and without a diagnosis of dementia, and to ascertain the cumulative incidence of dementia after care entry.

Design

Retrospective cohort study using the Registry of Senior Australians (ROSA) National Historical Cohort.

Setting and Participants

Individuals aged 65 to 105 years who entered LTCFs between 2009 and 2018, received a cognitive evaluation, and had no recorded dementia diagnosis at the time of care entry.

Methods

Cognitive function was determined via the Psychogeriatric Assessment Scales–Cognitive Impairment Scales (PAS-CIS) and defined as none or minimal (PAS-CIS score 0 to <4), mild (4 to <10), or moderate to severe (10 to 21). The cumulative incidence of dementia, determined by aged care assessments, hospitalization, medication, or cause of death, was ascertained for the total cohort and by cognitive impairment status at care entry.

Results

In total, 90,122 individuals [median age 85 years; interquartile range (IQR) 81–89; 64.6% female] were studied, of whom 76.6% (n = 69,075) had cognitive impairment, including 51.4% (n = 46,350) with mild and 25.2% (n = 22,725) with moderate to severe impairment. Over a median follow-up of 1.5 years (IQR 0.6–2.9), the cumulative incidence of dementia was 26.8% [95% confidence interval (CI), 26.5–27.1]. Stratification by cognitive impairment status showed the cumulative incidence of dementia was 17.4% (95% CI, 16.8–17.9) for none or minimal, 27.3% (95% CI, 26.9–27.8) for mild, and 35.3% (95% CI, 34.7–36.0) for moderate to severe.

Conclusions and Implications

The cohort of people entering LTCFs with cognitive impairment had a high incidence of dementia diagnosis within 1.5 years after entry. Routine cognitive impairment assessments can inform dementia screening strategies by identifying individuals at higher risk of dementia.