Tell me about the study.
A secondary analysis assessed 23,776 women with a mean age of 64.4 ± 5.8 years were randomly split into two groups following two diets: 9,340 followed a low-fat (20%) diet, with increased vegetable (five servings per day), fruit (five servings per day), and grain intake (six servings per day); 13,877 followed their original diet, with no dietary modifications (DM). Researchers tracked both patient groups for a mean of five years. Data was collected using a food frequency questionnaire.
What did they find?
While researchers found no significant difference in primary OAG incidence between the two patients groups, those following a low-fat diet exhibited a significantly higher subsequent glaucoma risk in contrast to the group with no dietary changes.
Talk numbers to me.
The prevalence of POAG was 11.1 per 1,000 woman-years—which is a measurement of the effectiveness of contraceptives, where women use one form of contraception exclusively for a period of 1 year—(with a mean follow-up of 11.6 ± 7.4 years; mean DM duration 5.2 ± 3.2 years). There was no overall benefit of DM in minimizing the chance for POAG (HR = 1.04, 95% CI, 0.96-1.12).
However, additional evaluation of baseline dietary intake between the quartile groups found that DM of those in the lowest quartile group (with a percentage of total calories from daily fat at 33.8% or lower), showed an increased risk for developing OAG (HR = 1.22, 95% CI, 1.05-1.41 and interaction p value 0.007). (via)
Takehome.
The study authors concluded that, regardless of age or race, data suggests following a diet with a lower percentage of calories from fat at baseline leads to an increase for developing OAG.