Relationship Between Floppy Eyelid Syndrome and Obstructive Sleep Apnea Syndrome: An Umbrella Review.

Background: Obstructive sleep apnea syndrome (OSAS) is characterized by intermittent partial or complete interruption of airflow due to upper airway collapse during sleep. Increased eyelid elasticity and the presence of a lax tarsus are features that define floppy eyelid syndrome (FES). The prevalence of FES may reach up to 64.5% among patients with OSAS. Despite its strong association with cardiovascular events, OSAS remains largely underdiagnosed. The Methods: Systematic reviews were evaluated to investigate the association between OSAS and FES in adults. This umbrella review was registered in PROSPERO and followed the PICO framework to define the research question. From August 2023 to January 2025, multiple databases were searched using relevant terms. The methodological quality of the included reviews was assessed using the AMSTAR 2 tool. Certainty of evidence was evaluated using a GRADE framework adapted for umbrella reviews, and an overlap analysis was performed. Results: Seven systematic reviews were included. According to AMSTAR 2, most were classified as having low methodological confidence. The final GRADE certainty ranged from low to moderate. Overlap analysis indicated moderate overlap. Nevertheless, the included studies consistently reported an association between FES and OSAS. Conclusion: Consistent with previous literature, this review supports an association between FES and OSAS. Identification of FES or EL during clinical examination may increase suspicion of OSAS. Despite its clinical relevance, this association remains underrecognized, and further studies using standardized diagnostic criteria are needed to strengthen the available evidence.