June 10, 2021 — Individuals who drink lots of caffeine have the next threat of glaucoma, however provided that their genes already make them vulnerable to the attention illness, researchers say.
Folks with a father or mother or sibling recognized with glaucoma ought to take into account limiting caffeine to the quantity in two cups of espresso 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 should you’re focused on decreasing your threat of the illness, it’s one thing I’d undoubtedly entertain.”
Pascale and his colleagues reported their findings in Ophthalmology.
Glaucoma causes injury to the optic nerve, typically from elevated strain from a buildup of fluid inside the attention. It will possibly trigger blindness.
The illness is extra widespread in individuals with shut members of the family who’ve it. And researchers have recognized variants in a number of genes which are extra widespread in individuals with glaucoma.
In earlier research, individuals who take giant doses of caffeine have had momentary will increase in eye strain. So researchers have puzzled whether or not getting caffeine over an extended time period might pose a threat.
To assist reply that query, Pasquale and his colleagues regarded on the information of greater than 100,000 individuals. The information got here from the UK Biobank, a big survey carried out in the UK. The information included data on sufferers’ genes, how a lot tea or espresso they drank, their eye strain, and whether or not they had glaucoma.
all of the contributors collectively, the researchers didn’t discover any elevated threat of glaucoma from caffeine. In truth, they discovered that individuals who acquired essentially 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 greater common eye strain and likewise to the next threat of glaucoma.
That was notably true once they regarded on the 25% of people that acquired greater than 321 milligrams of caffeine — the equal of three cups of espresso — a day. When these individuals had been additionally within the prime 25% of genetic threat for elevated eye strain, they’d a a lot greater threat of glaucoma. They had been nearly 4 occasions extra more likely to have the illness than individuals who didn’t eat caffeine and had been on the lowest 25% genetic threat.
The researchers discovered that the mixture of caffeine and genes elevated the danger of glaucoma greater than the genes alone.
The researchers couldn’t discover a statistical hyperlink to greater eye strain or glaucoma for espresso, just for tea. However that’s probably due to a statistical drawback, says examine co-author Anthony Khawaja, affiliate professor on the College Faculty London Institute of Ophthalmology. “The reply is sort of easy− the UK is a tea ingesting 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 research their glaucoma threat.
Folks in each the highest 25% for genetic threat and prime 25% for tea ingesting (three to six cups of tea a day), had been nearly thrice as more likely to have glaucoma in comparison with these within the lowest 25% for tea ingesting and lowest 25% for genetic threat.
Nonetheless, this kind of examine can’t show that caffeine will increase the danger of glaucoma or excessive eye strain, even amongst individuals with a genetic threat, Pasquale says. He and his colleagues wish to do a follow-up examine through which they provide caffeine to teams of individuals with completely different genetic dangers, then evaluate the consequences on eye strain.
Sufferers mustn’t depend on altering their caffeine consumption as a approach of treating their glaucoma, says Asaf Achiron, MD, an ophthalmologist on the Sackler College of Drugs 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 examine, he factors out.
“Glaucoma is a posh illness. In some instances 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 is likely to be value mentioning to sufferers, he says. “I do not focus on tea with my sufferers simply measure their [eye pressure]. Maybe I ought to.”