Visual contrast enhances food and liquid intake in advanced Alzheimer's disease

Patients with severe Alzheimer's disease (AD) in long-term care have deficient contrast sensitivity and poor food and liquid intake. The present study examined how contrast manipulations affect these intake levels.

Participants were nine men with advanced AD. Independent variables were meal type (lunch and supper) and condition (baseline, intervention, and post-intervention). Dependent variables were amount of food (grams) and liquid (ounces). Data were collected for 30 days (10 days per condition) for two meals per day. White tableware was used for the baseline and post-intervention conditions, and high-contrast red tableware for the intervention condition. In a follow-up study 1 year later, other contrast conditions were examined (high-contrast blue, low-contrast red and low-contrast blue).

Mean percent increase was 25% for food and 84% for liquid for the high-contrast intervention (red) versus baseline (white) condition, with 8 of 9 participants exhibiting increased intake. In the follow-up study, the high-contrast intervention (blue) resulted in significant increases in food and liquid intake; the low-contrast red and low-contrast blue interventions were ineffectual.

Simple environmental manipulations, such as contrast enhancement, can significantly increase food and liquid intake in frail demented patients with AD.