Longitudinal assessment of patient dependence in Alzheimer disease.
BACKGROUND
The Dependence Scale measures the amount of assistance patients with dementia require in performing daily activities. Validity and reliability of this scale have been demonstrated, but the progression throughout long periods in patients with Alzheimer disease (AD) has not previously been examined.


OBJECTIVE
To determine the longitudinal course of patient dependence in a cohort of prospectively followed AD patients.


METHODS
Two hundred thirty AD patients enrolled in the Predictors Study were followed up prospectively at 6-month intervals for an average of 6.5 visits. The Dependence Scale was administered to a caregiver, and patients were assessed with the modified Mini-Mental State Examination (mMMSE) and the Blessed Dementia Rating Scale. Dependence level and the additive sum of the Dependence Scale items were considered for analysis.


RESULTS
Generalized estimating equations to regression analyses were used to determine that both Dependence Scale scores and dependence level significantly decline with time. By covarying mMMSE scores and self-care deficits factor scores of the Blessed Dementia Rating Scale, generalized estimating equations analysis also demonstrated that change in patient dependence was independent of global cognitive decline and other measures of activities of daily living, respectively.


CONCLUSIONS
This study shows the validity of the Dependence Scale and demonstrated that dependency in AD significantly declines with time independent of global cognition and other self-care deficits. The scale is a valuable instrument for outcomes research, efficacy trials, and behavioral research in AD.
Brickman
Adam M
AM
Department of Neurology, Gertrude H. Sergievsky Center, Columbia University College of Physicians and Surgeons, 630 W 168th St, New York, NY 10032, USA.
Riba
Aliza
A
Bell
Karen
K
Marder
Karen
K
Albert
Marilyn
M
Brandt
Jason
J
Stern
Yaakov
Y
D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000401:mortality / Q000503:physiopathology*; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D016019:Survival Analysis