# Combined Chronotherapy for Poor Sleep Following Acute Coronary Syndrome: A Pilot Randomized Trial

## TL;DR

A pilot study tested a sleep improvement intervention for heart attack survivors using light therapy and found it was mostly feasible and well-received.

## Contribution

This is the first pilot trial of combined chronotherapy plus sleep hygiene for post-ACS sleep disturbance.

## Key findings

- High adherence to the chronotherapy intervention was observed in most patients.
- Most patients found the intervention feasible and usable, though fewer found it acceptable.
- Improvements in insomnia symptoms and sleep quality were reported in response to the intervention.

## Abstract

Sleep disturbance is common following acute coronary syndrome (ACS) and may contribute to a worse prognosis. We describe the rationale, design, and findings of a pilot and feasibility randomized clinical trial (RCT) of an intervention to improve post-ACS sleep. Fifteen post-ACS patients with insomnia and/or short sleep were randomized (2:1 allocation) to combined chronotherapy (CC) plus sleep hygiene education (SHE) or SHE control. CC was bright light therapy (BLT) delivered by a wearable light visor for 30 minutes after awakening and short-wavelength light avoidance using blue-light blocking (BLB) glasses in the evening from 8:00pm to bedtime daily for 4 weeks. Primary outcomes were feasibility, acceptability, appropriateness, usability, and adherence. Secondary outcomes were insomnia symptoms, sleep quality, and sleep duration. Two patients in the CC intervention group dropped before initiating study procedures. Completion of study procedures in remaining patients was high in the CC and control groups (88% and 100%, respectively). Self-reported adherence to CC (i.e., using BLT and BLB on ≥50% of days) was high (88% and 100%, respectively). The proportion of CC patients who perceived the intervention as feasible (71%) and usable (100%) was high, though fewer CC patients rated the intervention as acceptable (57%) and appropriate to improve sleep (29%). Improvements in insomnia symptoms and self-reported sleep quality and duration were seen in response to the CC intervention (71%). Post-ACS patients with sleep disturbance had high adherence to this chronotherapeutic intervention, and most viewed it as feasible and usable. This intervention should be tested in a larger RCT to determine efficacy to improve sleep.

ClinicalTrials.gov number NCT05299723

March 29, 2022

https://classic.clinicaltrials.gov/ct2/show/NCT05299723