A new study claims people who suffer from both insomnia and osteoarthritis are at a greater risk of intense knee and joint pain. The study correlated osteoarthritis with insufficient sleep patterns and suggests insomnia may have a direct relationship with how humans experience pain.

In the study, Claudia Campbell, the lead researcher from the Johns Hopkins University School of Medicine in Baltimore, discovered that people who suffer from both osteoarthritis and insomnia have a nervous system disorder called “central sensitization.” This disorder makes the sufferer more sensitive to pain.

“Knee osteoarthritis patients with insomnia have more pain and worse physical function than knee osteoarthritis patients without insomnia,” said Campbell in a statement.

The study analyzed sleep and pain patterns in four groups of people – individuals with insomnia and osteoarthritis, people with only joint problems, people with insomnia but no joint disorder, and healthy individuals with neither disorder. The researchers found that people with insomnia and osteoarthritis were far more sensitive to pain. 

According to statistics from the World Health Organization, nearly 1 in 10 men and 1 in 5 women over the age of 60 suffer from osteoarthritis globally. The American Academy of Sleep Medicine says about one-third of adults suffer from insomnia, with 1 in 10 individuals having its chronic form.

The study was published in the journal Arthritis Care & Research.