Light up: an intervention study of the effect of environmental dynamic lighting on sleep–wake rhythm, mood and behaviour in older adults with intellectual disabilities

Abstract

scores on the ADAMS depression (À0.64 SD, P < 0.001) and social avoidance (À0.47 SD, P = 0.004) subscales. The prevalence of screening above cut-off for depression decreased from 23 to 9.8% (OR = .16, P = 0.003). For behaviour, a decrease was seen in hyperactivity (À0.43 SD, P < 0.001), lethargy (À0.35 SD, P = 0.008) and irritability (À0.33 SD, P < .001) as measured with the ABC. No adverse effects were reported. Conclusion Installing dynamic lighting in common living areas for older adults with ID improved the mood and behaviour of the residents up to 14 weeks after placement. Integrated dynamic lighting is a promising, undemanding and potentially effective addition to improve mood and behaviour in care organisations for people with ID, but does not seem to do so by improving sleep or sleep-wake rhythms.

Efficacy of light intervention in improving mood and behaviour, but not sleep in intellectually disabled older adults

“…Böhmer et al 3 performed a non-randomised, non-concurrent, multiple baseline study to investigate the effect of environmental light intervention on sleep-wake rhythm, mood and behaviour in older adults with ID living in residential care facilities (N=54). After three baseline assessments on sleep (evaluated by actigraphy), mood (Anxiety, Depression and Mood Scale, ADAMS) and behaviour (Aberrant Behaviour Checklist, ABC) at weeks 1, 5 and 9, ceiling-lightening was installed at week 10.…”

“…Although the findings by Böhmer et al 3 point to beneficial effects of environmental lightening protocol on mood disorder and behaviour in ID individuals, it seems necessary that future studies should investigate the optimal protocol features to affect sleep variables.…”

Long‐term effects of environmental dynamic lighting on sleep–wake rhythm, mood and behaviour in older adults with intellectual disabilities

“…Light exposure at 7:00 p.m. was 23 lux (SD = 8 lux) during baseline and 85 lux (SD = 34 lux) during intervention. A full description of the dynamic lighting installation and an overview of illuminances during the baseline and intervention periods are presented elsewhere (Böhmer et al 2022).…”

“…This made it impossible to report reliable data on personal daily light exposure during the study period. In order to measure whether the light levels in the common living room increased after the placement of the light installations, light exposure in the living room was measured 1 day during the last week of baseline and 1 day during the first week after the placement of the light installation, and we presented these data in the paper of the initial study (Böhmer et al 2022). Over the study period, the light levels in the common rooms increased from 68 lux (SD = 46 lux) at baseline to 989 lux (SD = 211 lux) during intervention.…”

“…Recently, we conducted a study on the short‐term effect of increasing environmental light exposure in group homes for older adults with IDs (Böhmer et al . 2022). Installing environmental dynamic light in the common living rooms did not affect stability and fragmentation of the sleep–wake rhythm within 14 weeks after placement, but small advancing effects were seen on sleep onset time and mid‐sleep.…”