People with age-related macular degeneration, a common cause of blindness in older adults, have a significantly increased risk of fractures, according to a new study.

Macular degeneration typically occurs in people over 50. Unlike blurred vision in older people, it is characterized by symptoms such as decreased central vision and blurred objects even after wearing glasses.

On Wednesday, a research team, led by Professors Ham Don-il, Lim Dong-hee, and Yoon Je-moon of the Department of Ophthalmology and Professor Shin Dong-wook of the Department of Family Medicine at Samsung Medical Center, released the results of a cohort study of 3,894,702 people aged 50 and older who underwent a National Health Insurance Service health checkup in 2009, following them up until 2019.

A total of 47,266 people (2.21 percent) were diagnosed with macular degeneration at the time of the initial examination, and the researchers measured the effect of macular degeneration on fractures.

The results showed 20.6 fractures per 1,000 person-years in the macular degeneration group. This compared to 12.6 in the control group. The relative fracture risk was also 9 percent higher in the macular degeneration group. This was after adjusting for other factors that affect fractures, including age and gender.

The same was true when seen by fracture types. Whether it was a hip fracture or a vertebral fracture, both life-threatening injuries in later life, the macular degeneration group had more incidents and a higher relative risk.

This was especially true when macular degeneration was combined with visual impairment. Compared to the control group, having macular degeneration but no visual impairment increased the fracture risk by 8 percent. However, the risk jumped to 17 percent when combined with visual impairment.

The researchers explained that impairments, such as poor vision due to macular degeneration, are a direct cause of fractures and can lead to loss of balance due to lack of exercise, making falling easier. As macular degeneration is also associated with a lack of vitamin D, the researchers said, a lack of vitamin D can lead to osteoporosis, making people more susceptible to fractures.

"If macular degeneration is suspected, prevention of fracture risk should be started simultaneously," Professor Yoon said. "If a person falls and breaks a bone in old age, recovery is slow, and disability can occur."

Professor Ham said this study identified a real risk factor for fractures posed by macular degeneration and laid the groundwork for further research into its relationship with osteoporosis,

“Through further research, we hope to prevent patients with macular degeneration from suffering from complications such as fractures," he added.