Abstract
The objective of this study was to examine the effects of morning bright light on behavioral disturbances in dementia using a repeated measures ABA design. We hypothesized that morning bright light in demented patients reduces the agitation rating and directly observed disruptive behavior, but increases observed positive behavior.
The study was done in a special care unit of a long term care facility, with 16 demented residents ages 60 to 89, 13 female and three male. Morning bright light (Day-Light Box 10000, produced by DayLight Technologies, Inc, providing 10,000 lux) was administered Monday to Friday during the treatment week. The Global Deterioration Scale rating at baseline, followed by baseline, treatment and post-treatment ratings in the Cohen-Mansfield Agitation Inventory (CMAI) and Environment-Behavior Interaction Code (EBIC) were used as measurements
Compared to baseline, the mean total Cohen-Mansfield score decreased more during the phototherapy week than during the post-treatment week (p < 0.05 on one-tailed paired t-test). Regardless of phototherapy, Cohen-Mansfield scores decreased significantly in summer versus fall-spring (p < .005). Although the direct behavioral measures [EBIC] showed no statistically significant change compared to baseline, there was a pattern of greater mean increase in positive behaviors (p = .08) during phototherapy than in the post-treatment week, and a mean decrease of total disruptive behaviors most pronounced in the post-treatment week (p = .05).
Bright light therapy has modest efficacy in reducing agitation, with possible concurrent improvement in positive behaviors. Disruptive behaviors may also become less frequent during phototherapy with evidence of even greater delayed optimal effect. Further research should focus on subgroups of patients demonstrating a particularly robust response, enhance power through a larger sample, provide for longer light exposure, and control for seasonal variables.