DENVER (FRONTLINE MEDICAL NEWS) – Recreational exercise and tumor necrosis factor–inhibitor therapy provide synergistic improvement in the functional status of patients with ankylosing spondylitis, according to an analysis from the multicenter Prospective Study of Outcomes in Ankylosing Spondylitis (PSOAS).

Among 683 PSOAS participants prospectively followed for up to 12 years, those who consistently engaged in moderate recreational exercise, defined as at least 120 minutes of exercise per week, had significantly lower, more favorable Bath Ankylosing Spondylitis Functional Index ( BASFI ) scores during years 1-5 than did those who exercised less, even after controlling for baseline function and other potential confounders in a multivariate analysis, Dr. Lianne S. Gensler said at the annual meeting of the Spondyloarthritis Research and Treatment Network.

Additionally, a significant interaction was observed between exercise time and anti-TNF therapy. BASFI scores improved through 5 years of follow-up in TNF inhibitor users regardless of their exercise status, but the impact on functional status was “strikingly” greater in those patients on a TNF inhibitor who engaged in at least 120 minutes of exercise per week, according to Dr. Gensler of the University of California, San Francisco.

“This suggests that it’s not simply taking a TNF inhibitor that’s going to promote long-term function. These patients should also be exercising to synergize and get the best out of their therapy,” she emphasized.

The PSOAS cohort included averaged 43 years of age at baseline, with a mean 19-year disease duration and an average of 2.1 comorbid conditions. In a multivariate longitudinal analysis, several factors emerged as significant predictors of more pronounced functional impairment over time: being age 40 or older at baseline was associated with a 25% increased risk, opiate use was associated with a 12% increase in risk, a baseline Bath Ankylosing Spondylitis Disease Activity Index ( BASDAI ) score of at least 40 conferred a 19% increase in risk, as did a modified Stoke Ankylosing Spondylitis Spinal Score of 4 or greater.

Dr. Gensler drew a sharp distinction between the effects of moderate recreational exercise and occupational physical activity in ankylosing spondylitis patients. In an earlier landmark study involving 397 members of the PSOAS cohort with at least a 20-year history of ankylosing spondylitis, investigators mapped the patients’ work histories, the physical activities their work entailed, and the time they spent at each activity. Jobs that involved repeated bending, stretching, twisting, and vibration exposure were associated with worse BASFI scores and greater radiographic disease severity ( Arthritis Rheum. 2008 Jun 15;59[6]:822-32 ).

Taking a step back to summarize what’s known today about what affects outcomes in ankylosing spondylitis patients, Dr. Gensler listed in the ‘bad’ column smoking, ongoing inflammation, baseline damage to the spine, certain occupational activities involving biomechanical stress, adiposity, and low socioeconomic status.

What’s good for patients with ankylosing spondylitis is physical therapy and back exercises – both will receive favorable marks in soon-to-be-published American College of Rheumatology guidelines on the management of ankylosing spondylitis that Dr. Gensler worked on – as well as TNF-inhibitor therapy, NSAIDs, and recreational exercise, which wasn’t addressed in the former guidelines.

Dr. Gensler reported receiving research funds from or serving as a consultant to AbbVie, Amgen, Celgene, Janssen, and UCB.