Seasonal variation of intra-ocular pressure in glaucoma with and without dry eye

Abstract

the management of intra-ocular pressure (iop) is important for glaucoma treatment. iop is recognized for showing seasonal fluctuation. Glaucoma patients can be at high risk of dry eye disease (DeD). We thus evaluated seasonal variation of iop with and without DeD in glaucoma patients. this study enrolled 4,708 patients, with mean age of 55.2 years, who visited our clinics in Japan from Mar 2015 to Feb 2017. We compared the seasonal variation in IOP (mean ± SD) across spring (March-May), summer (June-August), fall (September-November), and winter (December-February). IOP was highest in winter and lowest in summer, at 14.2/13.7 for non-glaucoma without DED group (n = 2,853, P = 0.001), 14.5/13.6 for non-glaucoma with DED group (n = 1,500, P = 0.000), 14.0/13.0 for glaucoma without DED group (n = 240, P = 0.051), and 15.4/12.4 for glaucoma with DED group (n = 115, P = 0.015). Seasonal variation was largest across the seasons in the glaucoma with DeD group. iop was also inversely correlated with corneal staining score (P = 0.000). In conclusion, the seasonal variation was significant in most of study groups and IOP could tend to be low in summer. Glaucoma is the second leading cause of blindness worldwide 1. Elevated intra-ocular pressure (IOP) is the only adaptable risk factor for glaucoma and the progression of visual field loss is strongly related to IOP. The management of glaucoma aims to reduce IOP 2,3 , which could be influenced by various factors including blood pressure, body posture, and diurnal and seasonal variations 4-6. Mean IOPs are reportedly higher in winter and lower in summer in both normal 7-9 and glaucoma 10,11 subjects, and the magnitude of these fluctuations are larger in patients with glaucoma than in normal subjects. Clinically, it is important to control IOP since a large diurnal fluctuation in IOP is a known risk factor for the progression of glaucoma 12. Seasonal and diurnal fluctuations could thus mislead a clinical decision regarding medication and surgery. Although this seasonal pattern was described two decades ago, the phenomenon is not completely characterised 8. Due to the chronic nature of glaucoma, many affected patients experience long-term exposure to commercial pharmaceutical components and preservatives that are known to cause corneal and conjunctival toxicity 13-15. Previous studies have shown that up to 40% of glaucoma patients use more than one topical medication 16 , and benzalkonium chloride (BAK), the most common preservative in anti-glaucoma solutions, has been strongly implicated in inducing and/or exacerbating ocular toxicity such as corneal epithelial cell dysfunction and inflammatory and toxic side effects on the conjunctiva. Consequently, glaucoma-affected patients can be at high risk of also developing the commonly seen dry eye disease (DED) 17-19. DED also exhibits seasonal fluctuations in vulnerability against environmental conditions. DED signs and symptoms tend to vary throughout the year, and particularly with seasonal changes across summer to winter 8. These ...

Intraocular Pressure and Its Relation to Climate Parameters—Results From the Gutenberg Health Study

“…Our findings are supported by other studies in healthy subjects 4 , 17 , 18 : One study with 103 healthy Chinese participants found an IOP difference of 1.4 ± 0.7 mm Hg between winter and summer, with higher IOP in winter months. 3 Analyses in this subject area in Chicago, Illinois, United States, recorded an IOP peak in December/January (15.7 ± 3.7/15.7 ± 3.8 mm Hg) and lowest IOP in September (14.5 ± 3.1 mm Hg).…”

“… 17 Similarly, studies examining glaucoma patients concluded that IOP is subject to periodic IOP changes. 4 , 17 , 18 …”

Does the order of intraocular pressure measurement affect tonometry results?

“…However, there was no correlation between IOP and tear film osmolarity or TFBUT in these patients. Similarly, in a study of 4708 normal subjects and glaucoma patients, there were no differences in IOP between patients with and without dry eye disease in either group 28 …”

Influential Signs of Dry Eye–Related Ocular Symptoms in Participants With Unstable Tear Film

“…Exploring the signs that influence DED symptoms can help establish the necessity for additional DED metrics. 5…”

“…Exploring the signs that influence DED symptoms can help establish the necessity for additional DED metrics. 5 In the suggested diagnostic criterion, both sign and symptom measurements are important tools for monitoring DED progression and response to treatment. 2 As the most commonly used measurement, subjective symptoms can be evaluated using the Ocular Surface Disease Index (OSDI) or other questionnaires, and tear break-up time (TBUT) is used to evaluate tear film stability, which is considered as the key sign of DED.…”