Time-of-Year Variation in Intraocular Pressure. Issue 11 (November 2021)

• Record Type: Journal Article
• Authors: Morettin, Christina E.; Roberts, Daniel K.; Newman, Tricia L.; Yang, Yongyi; McMahon, Janice M.; Roberts, Mary Flynn; Teitelbaum, Bruce A.; Winters, Janis E.
• Is Part Of: Journal of glaucoma. Volume 30:Issue 11(2021)
• Publication Date: 2021-11
• Subjects: intraocular pressure -- glaucoma -- seasonal -- time of year -- annual periodicity; Glaucoma -- Periodicals; 617.741005
• DOI: 10.1097/IJG.0000000000001930
• Languages: English
• ISSNs: 1057-0829

Abstract

Abstract : Précis: In this study conducted in Chicago, IL, intraocular pressure (IOP) level was found to have a subtle, but measurable, annual pattern. Reasonable evidence is presented for a time-of-year variation in IOP. Adequate numbers of subjects must be studied to detect this small variation. Purpose: The aim was to investigate the relationship between IOP and time of year. Methods: During a separate investigation, patients from 2011 to 2018 (dataset A, N=3041) in an urban, academic facility in Chicago, IL received an examination that included Goldmann applanation tonometry. Regression analyses assessed the relationship between time of year and IOP. Two additional datasets, 1 collected in a similar manner during 1999 and 2002 (dataset B, N=3261) and another consisting of all first visits during 2012 and 2017 (dataset C, N=69, 858), were used to confirm and further investigate trends. Results: For dataset A, peak mean IOP occurred in December/January (15.7±3.7/15.7±3.8 mm Hg) and lowest in September (14.5±3.1 mm Hg). The analysis suggested conventional quarterly analysis (January to March, etc.) can conceal time-of-year relationships because of inadequate statistical power and timing of IOP variation. Multiple linear regression analysis, with a November-to-October reordering, detected an annual, downward IOP trend ( P <0.0001). Analysis of dataset B confirmed this trend ( P <0.001). Fourier analysis on datasets A and B combined supported a 12-month IOP cycle for right/left eyes ( P =0.01/ P =0.005) and dataset C provided stronger evidence for an annual periodicity ( P <0.0001). Harmonics analysis of dataset C showed a repeating pattern where IOP trended downward around April, and then back upward around October. Conclusions: This analysis strongly supports a demonstrable annual, cyclical IOP pattern with a trough to peak variation of ≈1 mm Hg, which has a seasonal relationship. Abstract : Supplemental Digital Content is available in the text.