Most weight loss strategies associated with increased risk of glaucoma

VANCOUVER, British Columbia – Eating less was the only weight loss strategy found to decrease the odds of developing glaucoma, according to a poster presented here at the Association for Research in Vision and Ophthalmology meeting.

Nikitha Reddy, MD , and colleagues conducted a retrospective cross-sectional study using the 2005-2008 National Health and Nutrition Examination Survey (NHANES).

The researchers reported in the poster that 3,076,410, or 3.7%, of the 83,643,392 subjects in the NHANES study had glaucoma, which was defined as more than two abnormal points on visual field tests and cup-to-disc ratio (CDR) or CDR asymmetry of at least 97.5% of the NHANES population.

Reddy told Healio.com/OSN that she and her colleagues looked at the risk of glaucoma associated with a range of weight loss strategies.

“We found there was a decreased risk of glaucoma associated with eating less in order to lose weight, and there was an increased risk of glaucoma associated with exercise, using diet supplement pills, dietitian consult or drinking more water with glaucoma,” she said.

The retrospective, cross-sectional nature of the research has many limitations, Reddy noted.

“Ideally, we could do it prospectively and have a temporal analysis to see if this is a long-term effect or temporary; we don’t really know,” she said.

She also noted that there have been no studies on the relevance of dietitian consults.

“But eating less – there’s been a study that showed patients have decreased IOP when they fast,” Reddy said. “But in comparison to that, there has been a study that showed in patients who fast, they drink more water because they’re fasting, so that elevates their IOP. There are contradicting statements there.

“But anything that seems to increase the episcleral venous pressure will decrease the outflow of the aqueous humor, so that could lead to increased IOP,” she continued. “Drinking more water acts along that mechanism. There’s a water drinking test that follows the same physiological mechanism for that.”

Another drawback of this study was the fact that patients answered “yes” or “no” regarding exercise, she noted.

“Aerobic exercise has been shown to decrease IOP and decrease risk of glaucoma, but exercises like weightlifting or anything that increases your venous pressure, anything that causes you to bear down, that has been hypothesized to elevate your IOP and perhaps have increased risk of glaucoma,” Reddy said. – by Nancy Hemphill, ELS, FAAO

Reference:

Reddy N, et al. Associations between weight loss strategies and glaucoma in the National Health and Nutrition Examination Survey. Presented at: Association for Research in Vision and Ophthalmology; April 28-May 2, 2019; Vancouver, British Columbia.

Disclosure: Reddy reports no relevant financial disclosures. Please see study abstract for all other authors’ disclosures.