Analyzing the Association of Ambient Solar Radiation on Biomechanical Properties of Cornea in Adult Patients: Alien or Population-Based Study
Narrative Responses:
Purpose
To analyze the association of ambient solar radiation (ASR) on biomechanical properties of the cornea in adult patients
Methods
The ALIENOR (Antioxydants, Lipides Essentiels, Nutrition and maladies OculaiRes) Study is a population-based epidemiological study on age-related eye diseases. In 2009-2010, 625 subjects, aged 75 years or more, had an eye examination and an evaluation of corneal biomechanics using the ocular response analyser® (ORA®, reichert inc., USA). Mean lifetime ASR was estimated using residential history, Global annual radiations using astronomic formulas and the statistics of sunshine hours at each location. For each participant, average ASR was estimated by weighting annual ASR at each location by the time spent at that location. Participants were classified in 3 groups (Group 1: <39.65 kJ/cm2, Group 2: 39.65-40.17 kJ/cm2 (reference), Group 3: >40.17 kJ/cm2). Corneal hysteresis (CH), corneal resistance factor (CRF) and CCT parameters were analyzed between groups.
Results
After adjustment for age and gender, there was a significant association of CH and CRF values with SR higher than 40.17 kJ/cm2 (CH: -0.48mmHg, 95% confidence interval (CI): -0.86;-0.09, p=0.015/ CRF: -0.40mmHg, 95% CI: -0.78; -0.02, p=0.038), whereas there was no significant association of CH and CRF values with SR lower than 39.65 kJ/cm2 (CH: -0.04mmHg, 95% CI: -0.42; 0.35, p=0.85/ CRF: 0.09mmHg, 95% CI: -0.29; 0.47, p=0.64). The CCT was not significantly associated with SR ( SR<39.65: CCT:-4.43µm, 95%CI: -13.92;5.05, p=0.36/ SR> 40.17: CCT: -6.95µm, 95%CI: -16.53;2.62, p=0.15)
Conclusion
CH and CRF were significantly lower in subjects exposed to high ambient solar radiation. Ambient UV exposure might induce histological changes of the cornea that influence its biomechanical properties