Risk Factors Associated With Cognitive, Functional, and Behavioral Trajectories of Newly Diagnosed Dementia Patients

BACKGROUND: Dementia results in changes in cognition, function, and behavior. We examine the effect of sociodemographic and clinical risk factors on cognitive, functional, and behavioral declines in incident dementia patients.

METHODS: We used longitudinal data from the National Alzheimer's Coordinating Center to evaluate cognitive (Mini-Mental State Exam [MMSE]), functional (Functional Activities Questionnaire [FAQ]), and behavioral (Neuropsychiatric Inventory Questionnaire [NPI-Q] severity score) trajectories for incident dementia patients over an 8-year period. We evaluated trajectories of 457 patients with mixed effects linear regression models.

RESULTS: In the first year, cognition worsened by -1.518 (95% confidence interval [CI] -1.745, -1.291) MMSE points (0-30 scale). Education, race, and region of residence predicted cognition at diagnosis. Age of onset, geographic region of residence, and history of hypertension and congestive heart failure predicted cognitive changes. Function worsened by 3.464 (95% CI 3.131, 3.798) FAQ points in the first year (0-30 scale). Cognition, gender, race, region of residence and place of residence, and a history of stroke and hypercholesterolemia predicted function at diagnosis. Place of residence and a history of diabetes predicted functional changes. Behavioral symptoms worsened by 0.354 (95% CI 0.123, 0.585) NPI-Q points in the first year (0-36 scale). Age of onset, region of residence, and history of hypertension and psychiatric problems predicted behaviors at diagnosis. Cognition explained changes in behavior.

CONCLUSIONS: Sociodemographic characteristics and clinical comorbidities predict cognitive and functional changes. Only cognitive status explains behavioral decline. Results provide an understanding of the characteristics that impact cognitive, functional, and behavioral decline.