Methotrexate, a widely used and inexpensive drug often used as a first-line treatment for rheumatoid arthritis, is also effective in reducing pain and stiffness in patients with osteoarthritis of the hands, a new study finds. To date, there is no effective treatment for this disease.
Osteoarthritis (OA) causes joint cartilage to thin and joint surfaces to become rough, meaning joints may not move as smoothly. Although OA can affect any joint in the body, the stiffness and pain associated with hand OA can particularly affect a patient's ability to grip objects, dress, and eat.
According to the National Institutes of Health, the global incidence of hand OA increased by 82% from 1990 to 2019. About half of patients with symptomatic hand OA suffer from synovitis, inflammation of the lining of the joints, which is associated with pain and disease progression.
Researchers at Monash University and Alfred Hospital in Australia have found in a new study that an inexpensive drug called methotrexate can effectively reduce pain and stiffness in patients with symptomatic hand OA.
Flavia Cicuttini, corresponding author of the study, said: "In our study, as in most osteoarthritis studies, pain improved in both the placebo and methotrexate groups within the first month or so. However, pain levels remained the same in the placebo group, but continued to decrease in the methotrexate group at three and six months, when pain levels were still declining. Pain improved twice as much in the methotrexate group as in the placebo group."
Methotrexate is an immunosuppressant that is widely used in the first-line treatment of autoimmune and inflammatory arthritis, such as rheumatoid arthritis and psoriatic arthritis. It has been used to treat rheumatoid arthritis since the mid-1980s.
In the current study, 97 participants with hand OA complicated by synovitis (detected by MRI) received 20 mg of methotrexate or placebo orally once a week for 6 months. The primary outcome was pain reduction, measured using a 100-mm visual analog scale (VAS). Participants were asked to place a mark on the scale that corresponded to pain. Then measure and record the distance in millimeters from the lower end of the scale.
After six months, the mean change in VAS pain was -15.2 mm in the methotrexate group and -7.7 mm in the placebo group. The researchers concluded that methotrexate had a "modest but potentially clinically meaningful effect" in reducing pain.
"Based on these results, methotrexate may be considered when treating inflammatory hand osteoarthritis," Cicuttini said. "This provides clinicians with a treatment option because these patients tend to experience more joint damage."
The benefits of methotrexate are evident at around three months and are maintained after six months, meaning patients and their clinicians can decide whether to continue treatment after six months.
"At that point, patients and their doctors can decide whether to continue or stop treatment. This is very similar to how we treat other forms of inflammatory arthritis," Cicuttini said.
Adverse effects occurred in 62% of participants in the methotrexate group and 60% in the placebo group. Common side effects of methotrexate include nausea, vomiting, and loss of appetite, which are easily managed. Methotrexate may cause damage to the liver if taken long-term. In addition, because methotrexate reduces immune system activity, people who take it may be susceptible to infection.
"Further trials are needed to determine whether the effects of methotrexate last beyond 6 months, how long we need to treat patients, and whether methotrexate reduces joint damage in patients with osteoarthritis and related inflammation of the hands," Cicuttini said.
The research was published in The Lancet.