Obesity is associated with increased intraocular pressure compared with normal weight controls, and weight loss may have a positive effect, according to researchers in the Journal of Glaucoma.
The prospective case-control study included 25 morbidly obese subjects scheduled for bariatric surgery and 25 age- and sex-matched average weight controls.
IOP measurements were performed in seven positions, three while seated: sitting with head straight, head flexed to 30 degrees and head extended to 30 degrees; and four supine positions: supine flat, right lateral decubitus, left lateral decubitus, and head and upper body elevated at 30 degrees with a wedge pillow.
The second part of the study followed the same obese group 1 to 2 years after bariatric surgery using the same protocol.
Mean age was 43.1 years in the bariatric group and 44.5 years in the control group. Mean body mass index was 49.3 in the bariatric group and 22.7 in the control group.
The mean IOP in the obese group was significantly higher than the control group across each position by a mean difference of 2.5 mm Hg, according to the researchers. No difference was found in mean IOP among the three sitting positions within each group.
Researchers found a significant increase in IOP sitting in supine, right and left lateral decubitus compared with sitting with head straight in both groups.
A total of 19 subjects returned after bariatric surgery with mean time to follow-up of 17 months. Mean weight loss was 49.1 kg, or 36% of total body weight, according to the study.
After bariatric surgery, mean IOP was significantly lower, with a mean difference of 1.6 mm Hg. Right eye mean IOP was significantly lower after bariatric surgery in each position except for the right eye in left lateral decubitus, according to researchers.
Left eye mean IOP was lower after bariatric surgery in each position but only reached statistical significance in the supine head up and right lateral decubitus positions.
Through linear regression researchers concluded that every 10% body weight lost was correlated with a 1.4 mm Hg decrease in IOP in the right eye. Every 10 unit decrease in BMI was correlated with a 2.4 mm Hg decrease in IOP in the right eye.
The researchers concluded, that “...it may be worthwhile to recommend weight loss in overweight glaucoma patients, as IOP remains the only modifiable risk factor.” – by Abigail Sutton
Disclosure: The researchers reported no relevant financial disclosures.