A study has found that individuals with thinning in a specific retinal nerve layer face a 27% higher risk of developing atrial fibrillation years later. The research analyzed eye scans from over 90,000 participants, including a group of more than 39,000 who were followed for approximately a decade. The thinning of the retina was detectable before a formal diagnosis of atrial fibrillation was made. Researchers indicate that while eye scans should not replace existing heart monitoring methods, they could serve as an early warning signal for potential heart issues.
The study revealed that individuals diagnosed with atrial fibrillation had thinner layers in the retina compared to those without the condition. The thinning was particularly noted in the ganglion cell-inner plexiform layer, which was consistently observed across both study groups. Atrial fibrillation is a common form of irregular heartbeat that can be difficult to detect, as it may occur without symptoms. This condition increases the risk of stroke, heart failure, and death.
Data for the study was sourced from two large groups: AlzEye, which included over 50,000 patients aged 40 and older who visited a London eye hospital, and the UK Biobank, a long-term health study involving individuals aged 40 to 69. Researchers utilized common eye imaging techniques, including color photographs and optical coherence tomography, to assess retinal thickness and blood vessel features. Atrial fibrillation status was determined from hospital records and self-reported diagnoses.
The findings indicated that thinning in the nerve cell layer was the only retinal change confirmed across both groups. In the hospital-based group, individuals with atrial fibrillation also exhibited smaller retinal veins and altered blood vessel branching. The researchers noted that the thinning observed in the hospital group was comparable to about 13 years of age-related thinning and four times the thinning typically associated with daily alcohol consumption.
Longitudinal tracking of over 39,000 participants from the UK Biobank revealed that 838 developed atrial fibrillation, typically around four years after their initial eye scan. Each standard step of thinning in the nerve cell layer was linked to a 27% higher risk of later diagnosis. The retinal changes were detectable prior to the formal diagnosis of atrial fibrillation.
Researchers propose that the observed pattern may be due to the increased risk of silent strokes associated with atrial fibrillation, which could lead to nerve damage reflected in retinal thinning. They emphasize that eye scans should complement existing diagnostic tools for atrial fibrillation, as the condition is often missed with standard monitoring methods. Atrial fibrillation is expected to become more prevalent in the coming decades.