Clinical depression can worsen the symptoms of knee arthritis beyond what is evident on X-rays, according to a new study from the Journal of Bone and Joint Surgery (JBJS). Patients with mild to moderate knee arthritis are especially affected by depression, the study notes.
"Knee osteoarthritis is a common cause of pain and impairment in older adults," said Tae Kyun Kim, MD, study author and director of the Division of Knee Surgery and Sports Medicine at Seoul National University Bundang Hospital's Joint Reconstruction Center. "Often, the level of arthritic symptoms reported by patients is much more severe than what is represented by X-rays, which can make it difficult for the doctor to treat. The results of this study indicate that depression can play a major role in the way patients experience the symptoms of knee arthritis, and that even when X-rays show the arthritis is not severe, patients with depression may report significant pain," Dr. Kim said. "The relationship between pain and depression suggests that both should be considered by physicians when treating patients with knee osteoarthritis, particularly in those with X-rays not indicating severe damage to the joint."
The study included 660 men and women aged 65 years or older who were evaluated for the severity of their knee arthritis on X-rays, as well as symptom severity. Patient interviews and questionnaires were used to assess coincident depressive disorders. The study was conducted as a part of the Korean Longitudinal Study on Health and Aging (KLoSHA).
As expected, the researchers found the levels of pain attributed to knee arthritis were higher in patients whose X-rays indicated greater joint damage; however, they also found depressive disorders were associated with an increase in pain in patients with mild to moderate knee arthritis, even when X-rays did not show significant joint damage.
"When evaluating the results of this study, the contribution of depression to knee osteoarthritis symptoms was almost as important as the damage indicated on X-rays," Dr. Kim noted.
Knee arthritis typically affects men and women over 50 years of age, and occurs most frequently in people who are overweight. Common symptoms include:
- Pain or stiffness in or around the knee
- Swelling of the knee
- Limited range of motion when walking or moving the knee
- Knee weakness or a feeling of instability
In more severe cases, the knee joint may appear deformed, such as bowlegged or knock-kneed appearance, either bulging outward or toward the side of the leg. Knee replacement surgery is often performed in patients with severe symptoms.
Although studies have indicated depression is not uncommon among older adults, it remains largely underdiagnosed. According to the National Institute of Mental Health (NIMH):
- The risk of depression increases with other illnesses and when ability to function becomes limited.
- Estimates of major depression in older people range from 1 to 5 percent among those living in the community, to as high as 11.5 percent in hospital patients and 13.5 percent in those who require home healthcare.
- An estimated 5 million older adults have mild depression, which is often undiagnosed. Symptoms of depression may include feelings of sadness or hopelessness; loss of interest in activities that were once enjoyed; change in appetite or sleep patterns; difficulty thinking and remembering or frequent thoughts of death or dying.
"Despite the reported satisfactory outcomes of knee replacement surgery a percentage of patients still experience knee pain and impaired movement," said Dr. Kim. "Sometimes pain and disability after surgery is medically unexplained, so in these patients screening for depression might be a very good option."
Treating Depression: A New Approach
According to another study, adding an alternative approach to antidepressant treatment might hold the answer to helping older people facing depression as well as providing the kind of gentle exercise that offers fitness benefits without jarring movement.
Researchers at UCLA turned to a gentle, Westernized version of tai chi chih, the 2,000-year-old Chinese martial art. When they combined a weekly tai chi exercise class with a standard depression treatment for a group of depressed elderly adults, they found greater improvement in the level of depression—along with improved quality of life, better memory and cognition, and more overall energy—than among a different group in which the standard treatment was paired with a weekly health education class. The results of the study appear in the current online edition of the American Journal of Geriatric Psychiatry.
"This is the first study to demonstrate the benefits of tai chi in the management of late-life depression, and we were encouraged by the results," said first author Dr. Helen Lavretsky, a UCLA professor-in-residence of psychiatry. "We know that nearly two-thirds of elderly patients who seek treatment for their depression fail to achieve relief with a prescribed medication."
In the study, 112 adults age 60 or older with major depression were treated with the drug escitalopram, a standard antidepressant, for approximately four weeks. From among those participants, 73 who showed only partial improvement continued to receive the medication daily but were also randomly assigned to 10 weeks of either a tai chi class for two hours per week or a health education class for two hours per week.
All the participants were evaluated for their levels of depression, anxiety, resilience, health-related quality of life, cognition and immune system inflammation at the beginning of the study and again four months later.
The level of depression among each participant was assessed using a common diagnostic tool known as the Hamilton Rating Scale for Depression, which involves interviewing the individual. The questions are designed to gauge the severity of depression. A cut-off score of 10/11 is generally regarded as appropriate for the diagnosis of depression.
The researchers found that among the tai chi participants, 94 percent achieved a score of less than 10, with 65 percent achieving remission (a score of 6 or less). By comparison, among participants who received health education, 77 percent achieved scores of 10 or less, with 51 percent achieving remission.
While both groups showed improvement in the severity of depression, said Lavretsky, who directs UCLA's Late-Life Depression, Stress and Wellness Research Program, greater reductions were seen among those taking escitalopram and participating in tai chi, a form of exercise that is gentle enough for the elderly.
"Depression can lead to serious consequences, including greater morbidity, disability, mortality and increased cost of care," Lavretsky said. "This study shows that adding a mind-body exercise like tai chi that is widely available in the community can improve the outcomes of treating depression in older adults, who may also have other, co-existing medical conditions, or cognitive impairment.
"With tai chi," she said, "we may be able to treat these conditions without exposing them to additional medications."