Dawn Simulation and Postural Hypotension

One of the most physiologically demanding things that older people do every day is to get up in the morning. After spending a night laying flat, where the blood distributes evenly across the body, when they stand in the morning (and the blood rushes to their feet), their cardiovascular system may not be able to compensate and maintain blood flow to the brain. This phenomenon is known as orthostatic or postural hypotension. The investigators have found in a group of young individuals that use of a dawn-simulation light that gradually wakes the brain is able to increase cardiovascular tone prior to arising. The goal of this experiment is to determine whether this dawn simulation light is able to increase cardiovascular tone in older adults such that they would have reduced or absent postural hypotension when they awaken in the morning. This would greatly reduce the risks of falls and their associated morbidities in older adults.

Inclusion Criteria: History of falls or dizziness at exit from bed in the morning (at least two incidents in the past year) At least 20/200 corrected visual acuity Stable health Normal hearing Exclusion Criteria: Regular cigarette smoker Alcohol abuse Drug abuse

Anonymized individual participant data will be made available upon request following publication of summary data.

Gabel V, Miglis M, Zeitzer JM. Effect of artificial dawn light on cardiovascular function, alertness, and balance in middle-aged and older adults. Sleep. 2020 Oct 13;43(10):zsaa082. doi: 10.1093/sleep/zsaa082.