Lifestyle choices matter for vision loss
Excerpted from the January/February 2015 edition of AOA Focus
When it comes to the risk of vision impairment, a patient has no control over genetics. However, a patient can control lifestyle choices.
The findings highlight an opportunity for optometrists to play an increasing role on a health care team.
Quantifying the role of those choices has been a major goal of the Beaver Dam Eye Study, a longitudinal, population-based cohort study that has been ongoing since 1987.
"Our impetus was to determine the relationship of modifiable risk factors to age-related eye disease and vision impairment—and how common they are," says Ronald Klein, M.D., M.P.H., a retinal specialist and epidemiological researcher from the University of Wisconsin School of Medicine and Public Health who has worked on Beaver Dam since its inception.
Following a cohort of 4,926 people, ages 43 to 86 at the study's launch, the study has collected data on age-related cataract, age-related macular degeneration and diabetic retinopathy, among other conditions. Based on an initial assessment and follow-up every five years, the team examined lifestyle factors in relation to changes in best-corrected visual acuity (BCVA) over time.
Findings include the following:
Being a current or past smoker was related to a bigger change in the number of acuity letters lost over time. Specifically, current smokers lost 0.44 more letters over each five-year interval than people who never smoked.
Study participants who indicated they engaged in regular physical activity at least three times per week were less likely than sedentary participants to develop visual impairment over time. Around 2 percent of the active group developed visual impairment, compared with 6.7 percent of the sedentary group.
"It's important to note that even when incorporating factors such as age, income and conditions such as AMD and cataract, lifestyle factors were still associated with these outcomes," Dr. Klein notes. "Our data suggests these modifiable risk factors affect more than just eye conditions."
The study also included results related to alcohol consumption. Occasional drinkers—those who reported consuming alcohol in the past year—experienced a lower rate of visual impairment than nondrinkers. But Dr. Klein cautions against interpreting that result as a reason to encourage drinking.
Findings bolster messages
The findings may come as no surprise to ODs who commonly speak with patients about lifestyle choices.
"However, seeing such changes over time, in such a large group, helps put credence to our recommendations," says Janis Winters, O.D., an associate professor at the Illinois College of Optometry who practices in Chicago. She does caution that though the study population is large, it is also largely Caucasian; performing such research on varied populations is a future opportunity.
Still, Dr. Winters sees the study as reinforcing the messages ODs share with patients. She says the findings highlight an opportunity for optometrists to play an increasing role on a health care team, flagging risks and communicating with other professionals about how patients can reduce them.
"For example," she says, "smoking is a big risk factor not only for ocular conditions but also for systemic conditions. This study gives us yet another reason to communicate the message about nonsmoking to patients—and also to better coordinate a quitting strategy as a