Folks with a guardian or sibling identified with glaucoma ought to think about limiting caffeine to the quantity in two cups of coffee a day, says Louis Pasquale, MD, an ophthalmology professor at Mount Sinai Well being System in New York Metropolis.
“It’s a suggestion,” he says. “It’s not one thing set in stone, however in the event you’re focused on decreasing your danger of the illness, it’s one thing I’d positively entertain.”
Pascale and his colleagues reported their findings in Ophthalmology.
Glaucoma causes harm to the optic nerve, usually from elevated strain from a buildup of fluid inside the attention. It could actually trigger blindness.
The illness is extra widespread in individuals with shut relations who’ve it. And researchers have recognized variants in a number of genes which might be extra widespread in individuals with glaucoma.
In earlier research, individuals who take giant doses of caffeine have had non permanent will increase in eye strain. So researchers have questioned whether or not getting caffeine over an extended time frame may pose a danger.
To assist reply that query, Pasquale and his colleagues regarded on the data of greater than 100,000 individuals. The data got here from the UK Biobank, a big survey performed in the UK. The data included info on sufferers’ genes, how a lot tea or espresso they drank, their eye strain, and whether or not they had glaucoma.
all of the members collectively, the researchers didn’t discover any elevated danger of glaucoma from caffeine. Actually, they discovered that individuals who received probably the most caffeine truly had barely decrease eye strain.
However once they regarded solely at individuals whose genes had been related to glaucoma, they discovered that caffeine was linked to larger common eye strain and in addition to a better danger of glaucoma.
That was significantly true once they regarded on the 25% of people that received greater than 321 milligrams of caffeine — the equal of three cups of espresso — a day. When these individuals had been additionally within the high 25% of genetic danger for elevated eye strain, that they had a a lot larger danger of glaucoma. They had been nearly 4 occasions extra prone to have the illness than individuals who didn’t eat caffeine and had been on the lowest 25% genetic danger.
The researchers discovered that the mix of caffeine and genes elevated the danger of glaucoma greater than the genes alone.
The researchers couldn’t discover a statistical hyperlink to larger eye strain or glaucoma for espresso, just for tea. However that’s possible due to a statistical drawback, says research co-author Anthony Khawaja, affiliate professor on the College School London Institute of Ophthalmology. “The reply is kind of easy− the UK is a tea consuming nation!” he says in an e mail. There have been most likely not sufficient individuals within the database who drink giant quantities of espresso to investigate their glaucoma danger.
Folks in each the highest 25% for genetic danger and high 25% for tea consuming (3 to six cups of tea a day), had been nearly 3 times as prone to have glaucoma in comparison with these within the lowest 25% for tea consuming and lowest 25% for genetic danger.
Nonetheless, any such research can not show that caffeine will increase the danger of glaucoma or excessive eye strain, even amongst individuals with a genetic danger, Pasquale says. He and his colleagues wish to do a follow-up research by which they provide caffeine to teams of individuals with completely different genetic dangers, then examine the results on eye strain.
Sufferers mustn’t depend on altering their caffeine consumption as a manner of treating their glaucoma, says Asaf Achiron, MD, an ophthalmologist on the Sackler College of Medication in Tel Aviv, Israel, who has studied the connection of way of life and eye strain. Caffeine didn’t have a giant impact for most individuals within the research, he factors out.
“Glaucoma is a fancy illness. In some circumstances it continues to progress even when [eye pressure] is lowered by the drops so clearly there are extra points right here than strain,” he says in an e mail.
Nonetheless, the discovering may be value mentioning to sufferers, he says. “I do not talk about tea with my sufferers simply measure their [eye pressure]. Maybe I ought to.”