Spring DST Clock Change May Increase Risk of New-onset PDR, Wet AMD

DST-related circadian disruption may be a modifiable risk factor for microvascular retinal disease, according to the results of a new nationwide cohort study. Photo: Rami Aboumourad, OD. Click image to enlarge. It’s known that daylight saving time (DST) transitions can disrupt circadian rhythm, and some studies have even found an association with cardiovascular events. Considering that changes in retinal vasculature can reflect systemic cardiovascular health, researchers recently explored whether DST transitions could predispose individuals to retinal diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). Their findings suggested that, in the short term, the biannual clock change could alter the risk of certain retinal conditions, with the spring transition showing higher risk for some conditions and the autumn transition appearing protective in others.The nationwide cohort study used claims data from the Merative MarketScan Commercial Database, comprised of commercially insured US adults aged 18 to 64 years between 2012 and 2014. In total, 12,640,343 patients met inclusion criteria, which required at least one year of enrollment (to confirm incident disease) and a 12-month lookback period. The average age was 42.2 years, and a slight majority of the cohort was female (56.2%). The team compared the one-week and one-month periods after autumn DST, spring DST and control periods in summer or winter, adjusting their analysis for age, sex, tobacco use, comorbidities, sleep disorders and prior retinal disease.Results varied by season and outcome. Compared with the summer control period, autumn DST was associated with a lower risk of retinal vein occlusion in the month afterward (hazard ratio, HR: 0.84) and proliferative DR (HR: 0.83). Spring DST was associated with a higher risk of proliferative DR (HR: 1.34) and neovascular AMD (HR: 1.24) in the month afterward. When winter was used as the control period, autumn DST was associated with lower risk across several outcomes in the month afterward, including retinal artery occlusion (HR: 0.75), retinal vein occlusion (HR: 0.66), proliferative DR (HR: 0.61) and neovascular AMD (HR: 0.64).In their paper discussing the study findings, published last week in Scientific Reports, the authors wrote, “While the pathophysiological mechanisms across the spectrum of retinal vascular disease are diverse and multifactorial, it is feasible that a proinflammatory state generated by circadian rhythm disruption serves as a common catalyst to increase risk of disease after spring DST transition, while autumn DST transition may confer an opposing protective effect.”The researchers observed that most of the strongest associations emerged at one month rather than one week, suggesting that the clock change may have a delayed effect. Additionally, they identified several factors that increased the risk of retinal vascular disease following DST transition, including older age, hypertension, ischemic stroke and prior diagnosis of retinal detachment, DR or AMD.An unexpected finding, according to the authors, was that sleep disorders—including obstructive sleep apnea, insomnia and hypersomnia/narcolepsy—did not appear to increase risk of retinal vascular disease after DST transition. This could suggest “that the long-term circadian misalignment observed in chronic sleep disorders has a different effect on cardiovascular pathophysiology compared to short-term circadian disruption after DST transition,” the team explained in their paper. It’s also possible that sleep disorder treatments may “mitigate acute vascular stress” from this short-term disruption in circadian rhythm, they added.The takeaway of this study, the authors conclude, is that “even short-term circadian rhythm disruptions have clinically significant effects on retinal microvasculature,” which they remark is “consistent with previous studies that have found increased stroke and acute myocardial infarction risk after DST transition.” As such, they posited, “DST-related circadian disruption may be a modifiable risk factor for microvascular retinal disease,” while advising clinicians to consider “close monitoring for signs and symptoms of new retinal vascular disease in patients, especially those with existing cardiovascular disease or retinal disease.”Click here for the journal source. Chan KS, Cheng BT, Banker MM, et al. Daylight saving time transition and new-onset retinal vascular disease: a nationwide cohort study. Sci Rep. June 26, 2026. [Epub ahead of print]. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.