While daylight saving may give us a little extra sunshine at the end of our workdays, the transition may be costing us our health
There is some light at the end of this tunnel, however, with indications that just a little extra sleep could offset some of the adverse health effects
Following studies suggesting sleep disruptions surrounding the shift in routine may put us at greater risk of heart attack and stroke, a new investigation has found evidence of both a jump and a slide in retinal vascular diseases in the wake of daylight saving changes, depending on the time of year
Researchers from Northwestern University in the US analyzed more than 12.6 million health records of adult volunteers in a commercial database collected between 2012 and 2014, counting diagnoses of retinal artery and vein occlusion, proliferative diabetic retinopathy, and neovascular age-related macular degeneration after fall and spring transitions and a summer or winter control period
What they found was indeed eye-opening. Risk of proliferative diabetic retinopathy and neovascular age-related macular degeneration surged by 30% in the weeks following the spring daylight saving transition. Conversely, the risk of PDR and retinal vein occlusion actually dropped after the fall shift by a whole 20%
“I think that relationship was pretty interesting, and it makes a lot of sense,” says the study’s first author, Kyle Chan, a physician at the Department of Ophthalmology
“There’s been literature showing that losing an hour’s sleep and circadian misalignment can cause inflammatory responses and metabolic derangements, and there’s also been some literature suggesting that getting an hour’s sleep in the context of daylight saving time might be protective.”
In theory, daylight saving time transitions provide society with a few more hours of visibility in the evening at a time of year when we can exploit the rays. Many argue for its economic benefit, opportunity for physical activity, and even its improvements to road safety
Yet the kick to the ol’ circadian rhythm is rarely pleasant. The loss of sleep that comes with “spring forward” has also been shown to be bad for our cardiovascular system
“This led us to ask if these similar effects would be happening in the retina, which is one of the most metabolically active tissues in the body and contains some of the body’s most complex microvascular networks,” says senior author and ophthalmologist Rukhsana Mirza
Retinal vein occlusion is caused by a blockage in a blood vessel that leads from the back of the eye, causing a sudden loss of vision. It affects around 2% of people over the age of 50, and is linked with the same risk factors as stroke and heart attack
Neovascular age-related macular degeneration is also a relatively common condition in our twilight years. Caused by abnormal growth of blood vessels, the condition seems to be on the increase. By 2050, the proportion of individuals over the age of 75 with the condition is expected to jump from around 10% to 17%
If getting extra shut-eye is all it takes to hold onto our vision as we age, then it just might be worth turning in a little earlier next spring
This research was published in the journal Scientific Reports
Fact-checked by Bronwyn Thompson
