Biodynamic lighting and functional disability: A single-case experimental design in three community dwelling people with dementia

Functional disability in people with dementia is associated with placement in long-term care facilities, feelings of depression and caregiver burden. As there is currently no cure for dementia, more attention is needed for personalised support for people living with dementia at home. A promising non-pharmacological innovation for reducing problems in functional activities is biodynamic lighting. This type of artificial lighting resembles a normal daylight curve, including changes in light intensity and colour during the day. The aim of this pilot study with three participants is to explore the possible influence of biodynamic lighting on functional activities over time on people with dementia living at home. The study used an A-B-A-B withdrawal single-case experimental design. In the intervention phases, the participants were exposed to biodynamic lighting, while in the placebo phases, the participants were exposed to placebo light. Both light phases came from the same light system. Based on this study protocol, the quantitative effects of biodynamic light related with functional activity did not reach significance. However, the qualitative results of lighting seem promising with a stabilisation of functional activity experienced over time. Future research should examine the effects that light may have on functional activity more in-depth. This study offers recommendations for longitudinal research.