MADRID – Patients with knee osteoarthritis who "retreated" into a passive coping strategy and engaged in an unhealthy lifestyle were likely to develop more long-term pain than were patients who stayed physically healthy and emotionally strong, in a large Dutch cohort study.
"To diminish pain in patients with early symptomatic OA [osteoarthritis], attention should be given not only to pain complaints, but also to effective use of coping strategies and unhealthy lifestyle factors," said the lead author of the study, Janet Wesseling, Ph.D., of University Medical Center, Utrecht, the Netherlands. "This is a further argument to take coping and lifestyle factors into account in the management of early OA."
Dr. Janet Wesseling
Her findings were extracted from data in the CHECK (Cohort Hip and Cohort Knee) study, a 10-year prospective cohort study with a mirror cohort in the United States. It’s following 1,002 patients with early OA-related complaints of hip and/or knee pain (Ann. Rheum. Dis 2013;72[Suppl. 3]:152)
The study’s pain trajectory subanalysis included 5-year data on 705 patients with symptomatic knee OA. Dr. Wesseling identified three trajectories in these patients: good, moderate, and poor pain outcomes.
Patients with a good outcome trajectory (n = 222) had over time a slight decrease in pain severity and ended up with a low pain severity. Those with a moderate outcome trajectory (n = 294) had a stable course of moderate pain over time. The poor outcome trajectory group (n = 189) had an increase in pain severity over time and ended up with severe pain.
Compared with the good-outcome group, participants in the other groups were significantly more likely to have a higher body mass index (odds ratio = 1.1). Patients in the moderate- and poor-outcome groups were significantly more likely to smoke than were those in the good-outcome group (moderate outcome, OR = 1.8; poor outcome, OR = 2.3), Dr. Wesseling reported at the annual European Congress of Rheumatology.
There were significant differences in coping strategies as well. The poorer-outcome groups were more likely to have a passive coping style. They were significantly more likely to worry about their condition than was the good-outcome group (moderate outcome, OR = 2.3; poor outcome, OR = 3.5), and more likely to rest often (moderate outcome, OR = 1.6; poor outcome, OR = 2.4).
Over the long run, there were also disease-related physical differences, Dr. Wesseling noted.
After 5 years, patients in the poor-outcome group experienced more joint destruction and changes in osteophyte size, she said. By that time, 13% of patients in the poor-outcome group had at least two grade changes on the Kellgren-Lawrence Grading Scale, indicating more joint space narrowing, osteophyte formation, sclerosis, and bony contour deformity.
Over time, these patients also experienced significantly more osteophyte enlargement than did patients in the moderate- and good-outcome groups, with a mean growth of 5.2 mm, compared with 3.4 mm and 2.9 mm, respectively.
Surgical outcomes were significantly different in the poor-outcome group, Dr. Wesseling said. There were 12 total knee replacements in the poor-outcome group, compared with 4 in the moderate-outcome group and just 1 in the good-outcome group.
Distinguishing different trajectories could have implications for treatment, Dr. Wesseling noted in an interview. Clinicians can suggest improvements in the way patients choose to deal with their condition – beginning with an up-front conversation.
"At the very least, the topic should be discussed during counseling on OA. Physicians should be alert to increasing stress levels in their patients. Sometimes, physicians can help counsel patients about managing stress, but a psychological consult might also be useful. And self-management programs can help patients manage and tolerate their pain."
The CHECK study is supported by the Dutch Arthritis Association. Dr. Wesseling and her colleagues had no disclosures to report.