Title: Momentary triggers, lasting impact: Environmental dynamics and agitation in dementia

BACKGROUND: Evidence on how environmental triggers in home settings lead to momentary agitation remains limited.

METHODS: This secondary analysis used BESI Phase II data and applied GAMM to examine relationships between levels of agitation and home environments through 181 agitation events from seven persons with dementia monitored for 30 days. Agitation and environmental measures were rank-transformed, and model assumptions were tested using residual distribution and concurvity.

RESULTS: Changes in noise showed a significant, non-linear relationship to agitation (edf=3.78, p<0.001). Changes in lighting displayed a negative linear relationship to agitation (edf=1.00, p=0.011). Mean temperature displayed a positive linear relationship to agitation (edf=1.00, p=0.003). Mean barometric pressure exhibited a significant non-linear relationship with agitation (edf=1.73, p=0.003). Mean humidity showed a non-linear, quadratic relationship to agitation (edf=2.60, p=0.004).

DISCUSSION: Agitation levels were shaped by moment‑to‑moment sensory variability, indoor microclimate conditions, and room‑level context, reflecting the dynamic and context‑responsive nature of environmental influence.