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Season, Weather, and Intraocular Pressure: A Monocentric Retrospective Analysis from 2016 to 2021
Cornelius Wiedenmann1, Daniel Böhringer1, Thomas Reinhard1
1Eye Center, Medical Center, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany.
Ophthalmic Epidemiology
|April 28, 2026
Summary
Intraocular pressure (IOP) shows seasonal variations, influenced by temperature and sunshine duration. Environmental factors and age significantly correlate with IOP, impacting eye health.
Area of Science:
- Ophthalmology and Environmental Science
- Investigates the interplay between physiological measurements and external environmental conditions.
Background:
- Intraocular pressure (IOP) is a critical factor in eye health, particularly for conditions like glaucoma.
- Understanding external influences on IOP can aid in predicting and managing ocular conditions.
Purpose of the Study:
- To investigate the relationship between intraocular pressure (IOP) and key environmental factors.
- To analyze the influence of daily mean temperature, sunshine duration, and atmospheric pressure on IOP.
- To assess seasonal variations and periodicity in IOP measurements.
Main Methods:
- Retrospective analysis of 199,804 outpatient IOP measurements (2016-2021) using non-contact tonometry.
- Exclusion of IOP values outside the 5-30 mm Hg range.
- Statistical analysis including ANOVA, multiple linear regression, and cross-correlations to evaluate environmental and demographic influences on IOP.
Main Results:
- A significant annual periodicity in IOP was observed, with highest levels in January and lowest in July.
- Multiple linear regression revealed significant negative correlations between IOP and daily mean temperature, age, and preceding 10-day sunshine duration.
- Atmospheric pressure and time of measurement did not show statistical significance.
Conclusions:
- An annual periodic variation in IOP, approximately 0.4 mm Hg, is confirmed.
- Environmental temperature appears to be the primary driver of IOP variation.
- Sunshine exposure over the preceding 10 days and potential secondary behavioral changes also contribute to IOP fluctuations.
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