DENVER (FRONTLINE MEDICAL NEWS) Weight loss enhances responsiveness of patients with psoriatic arthritis to tumor necrosis factor inhibitors and should be part of routine care when using these drugs in this setting, Lianne Gensler, MD, said at an educational symposium organized by the Spondyloarthritis Research and Treatment Network.

She cited results from a randomized study conducted in Naples, Italy, with 138 patients and published in 2014, which showed the greater the weight loss of patients with psoriatic arthritis (PsA) during their first 6 months on treatment with a tumor necrosis factor (TNF) inhibitor, the greater their rate of achieving minimal disease activity by the end of the first 6 months.

Patients achieving a 5%-10% weight loss in the first 6 months on TNF-inhibitor treatment had a nearly fourfold increased rate of minimally active disease, compared with patients who had anything less than a 5% weight loss (including patients who may have had no weight change or gained weight). Those who lost more than 10% of their starting weight had a nearly sevenfold higher rate of achieving minimal disease activity, compared with those who had anything less than a 5% weight loss (Ann Rheum Dis. 2014 June;73[6]:1157-62).

“I use this result in my routine practice when starting patients on a TNF inhibitor or when patients are not responding to TNF-inhibitor treatment,” said Dr. Gensler, director of the ankylosing spondylitis clinic at the University of California, San Francisco.

“It’s a patient-centered approach to improving outcomes,” she said at the symposium, also organized by the Group for the Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA).

The 2015 guidelines (Arthritis Rheum. 2016 May;68[5]:1060-71) for managing psoriasis and PsA from GRAPPA cite the Naples data to recommend that all PsA patients be encouraged to achieve and maintain a healthy body weight, she noted.

The evidence that weight can affect TNF-inhibitor response in PsA patients first dates to a prior report from the same Naples group, which prospectively followed 270 PsA patients starting a TNF-inhibitor regimen, including 135 obese patients and 135 at normal weight. After 12 months, 36% of patients had minimal disease activity. The obese patients were nearly fivefold more likely to not achieve minimal disease activity during the first 12 months on treatment, compared with the normal-weight patients (Arthritis Care Res. 2013 Jan;65[1]:141-7). Obesity also was linked with a significantly increased risk that patients who achieved minimal disease activity after 1 year would relapse by 2-year follow-up.

“These studies have provided a new reason for [PsA] patients to lose weight,” agreed Atul A. Deodhar, MD, professor of medicine and medical director of the rheumatology clinics at the Oregon Health and Science University in Portland. “Before we counseled patients to lose weight for other reasons. Now there is a rheumatologic reason.”

Smoking cessation is another lifestyle step recently shown to improve TNF-inhibitor response in PsA patients, Dr. Deodhar added. For example, results from a recent Danish study of 1,388 PsA patients enrolled in the Danish national registry showed that smokers had significantly worse responses, compared with nonsmokers, during their first 6 months on a TNF-inhibitor regimen (Ann Rheum Dis. 2015 Dec;74[12]:2130-6).

Both weight loss and smoking cessation “have a powerful effect. I use these results in my practice to counsel patients to stop smoking and lose weight [for] those going on a TNF inhibitor, or when a TNF inhibitor is not working,” Dr. Deodhar said in an interview.

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