Glaucoma Watch prev next

Jan 05 2010

Glaucoma Risk and the Consumption of Fruits and Vegetables in Older Women

posted by: Noreen Marron-Curdo, OD

Nutritional factors may influence the development of ocular diseases and antioxidants may protect against these diseases. This multi-centered longitudinal cohort study investigated the association of glaucoma risk and the consumption of specific nutrient rich fruits and vegetables.

Sample/Methods: The study included women aged 65 and older participating in a Study of Osteoporotic Fractures (SOF). The study sample began with 1274 women randomly selected to participate from the 5482 that were part of the SOF group. These patients had optic nerve images and VF’s evaluated by independent glaucoma specialists. Of these 1274 women, 1196 (94%) responded to the Block Food Frequency Questionnaire (FFQ), pertaining to eating habits over a one-year period. A small number of women (41) were excluded from the study because of unreadable ONH photographs, yielding a final sample size of 1155.

The sample was 87% White and 13% Black. Participants’ ages ranged from 67-97 years with a mean of 79.4 years. Nearly all of the women (95%) were not current smokers and 6% had diabetes. The Black women tended to be younger than the White study participants, with a higher percentage of smokers and diabetics. Of the 1155 study participants, 95 (8%) were diagnosed with glaucoma in at least one eye.

Analysis: The relationship between fruit and vegetable consumption and the risk of glaucoma was evaluated using logistic regression models, adjusting for potential confounders including study site, age, race, education, smoking status, exercise, BMI, self-rated health assessment, including diabetes and hypertension, alcohol consumption, and the presence of ARMD. The major nutrient components of fruits and vegetables were determined and the consumption of these nutrients along with total calories, fats, proteins, and carbohydrates were based on the FFQ.

Results: The odds of having glaucoma were decreased by 64% in women who ate fresh carrots more than two servings a week compared to those having less than one a week, after adjusting for potential confounding variables. Women who consumed one or more servings a month of fresh collards or kale were 69% less likely to have glaucoma compared to those who ate less than one serving per month. The odds of having glaucoma were decreased by 47% in women who ate one or more serving per month of canned or dried peaches compared to those who had less than one serving a month.

Interestingly, the odds of having glaucoma increased by 70% in women who drank at least one serving per day of orange juice compared to those who drank less than one serving per week. Women who ate more than one serving of spinach per week tended to have a greater chance of glaucoma diagnosis versus those who consumed less than one serving per month.

Conclusions: In summary, the authors conclude that certain fruits and vegetables may be associated with a decreased risk of glaucoma in older women. Females with a larger consumption of carrots, which are high in Vitamin A, alpha-and beta-carotenes; of collards or kale, which are rich in vitamins A, C, B2 and Beta-carotene; and of canned or dried peaches, which are rich in vitamin A, had a reduced odds of glaucoma diagnosis.

The study did not investigate the exact mechanism by which these nutrients and antioxidants may affect glaucoma. Of note, some antioxidants, such as vitamin C, were not associated with a reduction in the risk of glaucoma. Although these antioxidants are present in collards and kale, which did show reduced odds of glaucoma risk, other nutrients in these vegetables may have contributed to the reduced risk. The authors call for further investigations to determine the relationship between glaucoma and fruit and vegetable consumption.

Several caveats should be considered when interpreting these results. The findings may not be generalized to men or to those younger than 65 years old. In addition, the sample of Blacks in this study was significantly smaller and younger than the Whites. These findings also may be confounded by other risk factors related to a woman’s lifestyle since higher fruit and vegetable intake may be associated with a healthier overall lifestyle.

Citation: Anne L. Coleman, MD; Katie L. Stone, MD; Gergana Kodjebacheva, MD; Fei Yu, MD; Kathryn L. Pedula, MD; Kris E. Ensrud, MD; Jane A. Cauley, MD; Marc C. Hochberg, MD; Fotis Topouzis, MD; Federico Badala, MD; and Carol M. Mangione, MD on behalf of the Study of Osteopoptic Fractures Research Group. Am J Ophthalmol. 2008;145;1081-1089.