circAdian lighTing to prevenT deliriUm in NEurointensive care patients (ATTUNE): A cluster-period randomized controlled feasibility trial

• Applicant: Privatdozent Dr. Jochen Sembill
• Subject Area: Anaesthesiology ; Clinical Neurology; Neurosurgery and Neuroradiology
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560017625

This study, titled "circAdian lighTing to prevenT deliriUm in NEurointensive care patients (ATTUNE)," is a cluster-period randomized controlled feasibility trial designed to evaluate the potential of circadian bright light therapy (CBLT) to reduce the incidence of delirium in neurological intensive care unit (NICU) patients. Delirium, a frequent and severe complication in critically ill patients, is linked to increased morbidity and mortality, and long-term cognitive and psychiatric sequelae. This results not only in a direct patient-related clinical impact, but also in an enormous socio-economic burden on healthcare systems and patients' families. This trial aims to determine the feasibility and potential efficacy of CBLT, compared to conventional lighting, in preventing delirium, thereby informing the design of a future full-scale randomized controlled trial. This single-center trial spans 36 months, including 24 months of patient recruitment. The trial aims to enroll 80 adult patients with neurological conditions requiring intensive care medicine from a pool of 700 assessed for eligibility. The experimental intervention is comprised of CBLT, whereby patients will be exposed to daylight-comparable bright light with an illuminance of over 1700 Lux for a minimum of 12 hours per day, in comparison to the standard lighting conditions applied to the control group. CBLT will be emitted through ceiling-mounted devices that imitate the rhythm of sunlight, from sunrise to sunset, with the objective of positively realigning patients' circadian rhythm and, consequently, potentially reducing the incidence of delirium. The study intervention needs to account potential confounders such as light contamination of neighboring beds or due to seasonal changes of sunlight exposure through windows. We therefore plan to implement a cluster-randomization (1:1), assigning patients to therapy rooms and defined treatment periods according to the seasonal course. The primary endpoints are designed to assess the feasibility of the intervention and the study design, as well as the explanatory efficacy by the proportion of delirium-free assessments per patient. The feasibility will be determined based on the recruitment rates, the completeness of the CBLT administration and of the repeated delirium assessments. Secondary endpoints include the duration of mechanical ventilation, length of stay, and melatonin levels, thereby providing a biochemical proof of principle. The proposed feasibility trial will provide the first robust evidence on the practicality and potential benefits of CBLT in reducing the incidence of delirium within this patient population. This is of great importance for the planning of a future multicenter, confirmatory study, with the objective of improving delirium rates in critically ill patients.

• DFG Programme: Clinical Trials