Outcomes Compared for Patients with Alzheimer’s and Non-Alzheimer’s Dementia

Atlanta—A review of records from the National Alzheimer Coordinating Center’s Uniform Data Set (NACC-UDS) found that patients with Alzheimer’s disease (AD) transition more quickly to states of more severe dementia as measured by the Mini-Mental State Examination (MMSE) than patients with non-AD dementia. Patients with non-AD dementia, however, were more likely to be institutionalized or die.

The NACC-UDS is a large, longitudinal dataset funded by the National Institute of Aging that includes AD and non-AD dementia patients, and nondemented controls. Investigators from the University of Washington, Pharmaceutical Outcomes Research and Policy Program and the University of York, Centre for Health Economics compared transitions among mild, moderate, and severe health states, and to death or institutionalization for AD and non-AD dementia patients in the NACC-UDS.

Using scores from the MMSE, one of the most commonly used tools for assessing cognition in dementia, the authors classified patients as mild (27-20), moderate (19-10), or severe (<10). They calculated the association between previous and current MMSE stage and the association between previous MMSE stage and institutionalization using multinomial logistic models with random effects to account for individual and center level correlation, controlling for demographic characteristics and time since last observation.

The coefficients from the regressions were used to calculate predicted probabilities using the population means for each of the covariates.

The analysis was limited to 3418 patients with dementia and ≥2 observations with complete data for the covariates of interest. Of these patients, 52.3% were determined to have probable AD and 47.7% had possible AD. Average baseline age was 76.72 years, and the average MMSE score was 17.05. The majority of patients (50.4%) were female.

The authors reported that patients in a higher MMSE stage at their previous visit were associated with a higher MMSE stage or death at the next study observation. The regression coefficient for the previous MMSE stage was statistically significant in all cases, according to the authors.

Previous MMSE stage was also found to be strongly associated with institutionalization. White, non-Hispanic, unmarried patients were more likely to be institutionalized, with other factors being equal. Patients with non-AD dementia were more likely to be institutionalized than patients with AD.

The authors concluded that patients with AD in the NACC-UDS database transition more quickly to more severe stages of MMSE than non-AD dementia patients. Non-AD dementia patients are more likely to transition to institutionalization and death than patients with AD.—Charles Boersig