Improved indoor lighting improved healthy aging at home - an intervention study in 77-year-old Norwegians.

Healthy aging and good quality of life is important to allow older people to live at home. Lighting is a significant environmental attribute promoting visual, physical, and mental health. Due to normal visual age changes, older people need more light, but improving indoor lighting levels receives little attention. To investigate the impact of improved home lighting on abilities to perform activities of daily living (ADLs) and quality of life in healthy older people. Sixty healthy 77 years old living at home participated during the 4-month dark winter period. In the intervention group (IG, n=30), the living room lighting was optimized by providing lamps and a basic control system with three preset levels (normal, medium, low). Participants chose the light level and kept a diary. No change was implemented for the control group (CG, n=30). A questionnaire measured self-reported visual and general health and ability to perform ADL in regards to lighting before and after the intervention in both groups. In the IG, lighting levels significantly improved self-assessed lighting levels, abilities to perform ADLs, and read and write in the living room (all <0.03). In the CG the only change was a deterioration in performing ADLs <0.05). The difference in change was significant between the IG and CG (all <0.02). "Normal" lighting was the preferred level and increased comfort and well-being. The IG also resumed visually demanding tasks, and acknowledged that avoiding these tasks were mainly due to poor lighting. Good vision is essential in promoting healthy aging at home and require adequate lighting. This can easily be achieved using a basic light system. Adopting to higher lighting levels evolves quickly. Our results suggest that improved quality of light could improve quality of life, and lighting should be included as a factor promoting healthy aging at home.