456 - Viability of RUDAS as a screening tool for cognitive decline in primary health care settings

Abstract

Introduction

Primary Health Care (PHC) has an essential role in the early detection of people with cognitive impairment (CI). Rowland Universal Dementia Assessment Scale (RUDAS) is a brief cognitive test, appropriate for people with minimum completed level of education and easily adaptable to multicultural contexts. For these reasons it could be a good instrument for dementia screening in PHC. It comprises the following areas: recent memory, body orientation, praxis, executive functions and language.

Objectives

The objective of this study was to analyse the viability of RUDAS, as an instrument for the screening of CI in PHC. RUDAS viability in PHC was checked, and it's psychometric properties assessed: Reliability, Sensitivity, Specificity, Positive and Negative Predictive Value were studied. RUDAS was compared to Mini Mental State Exam (MMSE) as a “gold standard”.

Patients and Methods

RUDAS was administered to 150 participants older than 65 years, randomly selected from seven PHC physicians’ consultations in O Grove Health Center. The test battery also included Katz, Barthel and Lawton Indexes, MMSE and the Geriatric Depression Scale. For each instrument administration time, difficulties perceived while administration and participant's collaboration were recorded. RUDAS was administered again within one month to assess test-retest reliability. For dementia clinical diagnosis, patients were classified following the Clinical Dementia Rating (CDR) scale based on clinicians’ criteria and health records.

Results

RUDAS application was brief (7,58±2,10 minutes) and well accepted. RUDAS’ area under Receiver Operating Characteristic (ROC) curve was 0.965 (95% Confidence Interval (CI) = 0.91-1.00) for an optimal cut-off point of 21.5, with sensitivity of 90.0%, and a specificity of 94.1%. RUDAS did not correlate with depression. Education, socioeconomic status and urban or rural context did not contribute any variance to RUDAS total score.

Conclusions

RUDAS is a valid instrument to assess CI in PHC. It is easily applicable and appears to be culturally fair and free from educational level and language interference in bilingual contexts. However, longitudinal studies to determine its sensitivity to change in cognitive function over time are needed.