Development of the Korean Version of Alzheimers Disease Assessment Scale(ADAS-K) to Assess Cognition in Dementia

OBJECTIVES: To develop the Korean version of Alzheimer`s Disease Assessment Scale(ADAS-K), an instrument for assessment of cognitive decline and behavioral symptoms seen in persons with Alzheimer`s disease METHOD: Community-dwelling elderly with Alzheimer`s disease(n=198) and mild cognitive impairment (n=30) participated in this study to evaluate reliabilities and validities of ADAS-K. RESULTS: The ADAS-K demonstrated a high degree of internal consistency and excellent interrater and test-retest reliability and high concurrent validity. Optimal cutoff points for the ADAS-K and ADAS-K-cog were 20/21(sensitivity 91%, specificity 83%) and 17/18(sensitivity 91%, specificity 93%). CONCLUSION: The ADAS-K is valid and reliable instrument in Korean elderly with Alzheimer`s disease, that may have potential to improve research outcomes and reduce the time and costs of research.

The relationship between the Alzheimer's Disease Assessment Scale and other measures of dementia

BACKGROUND: The cognitive subscale of the Alzheimer's Disease Assessment Scale(ADAS-Cog) has been extensively valiated in assessing cognitive function in patients with Alzheimer's Disease(AD) and used as an efficacy measure in clinical trials of AD. There is a need for additional data on the relationship between cognitive performance and other measures of dementia to fully assess the value of the ADAS-Cog as a measure of treatment efficacy. METHODS: We used data from 53 AD participants in 8 multicenter clinical drug trials to examine the distribution of baseline ADAS-Cog scores in relation to Mini-Mental State Examination(MMSE), Global Deterioration Scale(GDES), Katz Index of Activity of Daily Living(ADL), Lawton Instrumental Activity of Daily Living(IADL), Geriatric Depression Scale(GDS) and Mini-Nutritional Assessment(MNA). RESULTS: The ADAS-Cog score was statistically significantly correlated with MMSE (R=-0.755, P<0.001), GDES(R=0.403, P<0.003), ADL(R=-0.532, P<0.001), IADL(R=-0.626, P<0.001) and MNA(R=-0.427, P=0.004) scores. But GDS scores were not associated with ADAS-Cog scores.(R= -0.123, P=0.396) CONCLUSIONS: This study characterizes the relationship between ADAS-Cog scores and other commonly used measures of dementia in AD patients. As expected, baseline scores on ADAS-Cog and MMSE demonstrated significantly high correlation. The relatively weaker correlation between ADAS-Cog and GDES scores may be related to the fact that GDES does not evaluate cognitive function only. There are also significant correlations between ADAS-Cog and ADL, IADL, and MNA which indicate the severity and progression of dementia in AD patients. Further studies with larger samples including cognitive function of broader spectrum need to confirm the findings in this study.