Young adults who are considered obese may be more likely to suffer from psoriatic arthritis, according to a study published in Archives of Dermatology.

Psoriatic arthritis is a joint condition that affects the fingers or toes and leads to stiffness and pain. Individuals who develop psoriasis, a skin-related disease, could have a higher risk of developing psoriatic arthritis.

In order to better understand how excessive weight gain could contribute to developing this type of arthritis, more than 900 individuals were enrolled in a six-year study. Of the group, 51 percent had been diagnosed with psoriatic arthritis and 27 percent had psoriasis.

The researchers then screened the body mass index (BMI) of each participant, and found that an unhealthy BMI at age 18 years was a sign of psoriatic arthritis later in life.

The results showed that 20 percent of overweight or obese participants developed psoriatic arthritis by age 45, while 20 percent of healthy-BMI individuals showed signs of joint problems by age 48.

“Patients with psoriasis represent a unique opportunity to identify individuals at very high risk of developing [psoriatic arthritis],” the authors stated. They added that “to determine which patients are at greatest risk, it is essential that risk factors be identified using robust epidemiologic approaches.”

Approximately 7.5 million Americans have been diagnosed with psoriatic arthritis. And of this population, 2.2 percent suffer from psoriasis, the National Psoriasis Foundation reports.