The difference between Bright Light Therapy and Biodynamic Lighting for patiënts with moderate-to-severe dementia: a double-blind, randomized, placebo-controlled trial.

INTERVENTION: The group patiënts (N = 60) are divided over 6 living rooms of a nursing home 'Atlant' in Apeldoorn, The Netherlands. All patiënts are exposed to bright light therapy (lux 1000‐2500, 10 AM‐ 6 PM), Circadian adjusted LED‐based lighting (0 ‐ 2500 lux, 2700‐6500K, 9 AM‐ 11 PM) and placebo light (standard light intensity, 300 lux, 10 AM ‐ 6 PM). Every intervention and placebo periods lasts 3 months. CONDITION: Dementia, Alzheimer, Vascular dementia, Frontotemporal dementia, Lewy‐body dementia, Cognition, Mood, Quality of life, Light therapy ; ; PRIMARY OUTCOME: ‐ Cognition (SIB‐II, MMSE); ; ‐ Quality of life (QUALIDEM); ; ‐ Depression (MADRS); ; ‐ Apathy (NPI‐NH Apathy scale); ; ‐ Agitation (CMAI); ; ‐ Rest‐activity Rythm (actigraphy) ; ; ‐ Activities of Daily Life (Katz‐ADL) SECONDARY OUTCOME: ‐ Dementia Severity (GDS) ; ; ‐ Year diagnosis dementia ; ; ‐ Dementia Types ; ; ‐ Age ; ; ‐ Gender ; ; ‐ Education Level (according to verhage criteria) ; ; ‐ Medical comorbidities in the last 6 months ; ; ‐ Medication use in the last 6 months ; ; ‐ Presence/absence of walking function ; ; ‐ falls incidence (number of falls a month before and during the study). ; ; ‐ Lux measurement: Before, after and during the intervention the light intensity will be measured by the supplier. During the intervention the light intensity will be independently measured by a luxmeter at the eye level in the gaze direction. The measurements take place two times in the week at the same time (12 o'clock PM) ; ; ‐ Light colour: Before, after and during the intervention the light colour (kelvin) will be measured by the supplier. INCLUSION CRITERIA: ‐ Patiënts with a clear diagnosis of dementia according to the ICD‐10 and/or DSM criteria ‐ Patiënts with dementia staying in a long‐term care nursing home 'Atlant Zorggroep' in Apeldoorn ‐ The Netherlands