LOS ANGELES – A provocative study opens the door for psoriasis and psoriatic arthritis to be added to the growing list of benefits following bariatric surgery.
“Although the natural history of psoriasis and psoriatic arthritis is typically chronic, the majority of patients experience improvement after bariatric surgery, Dr. Monica Sethi of New York University said at Obesity Week 2015.
Patrice Wendling/Frontline Medical News
Dr. Monica Sethi
At an average of 6 years after bariatric surgery, 55% of patients with psoriasis and 62% of those with psoriatic arthritis (PsA) reported subjective lessening of their disease.
Preoperative disease severity ratings on a 10-point scale significantly decreased at the most recent follow-up for psoriasis (5.6 vs. 3.3; P less than .01) and PsA (6.4 vs. 3.9; P = .02).
“Our results indicate an association between excess weight loss and symptomatic improvement in severe cases of psoriasis, and a possible improvement in psoriatic arthritis,” she said.
Although the effects of surgical weight loss on psoriasis and PsA are unknown, obesity is known to be more prevalent among patients with psoriasis and PsA. This correlation appears to be related to fat tissue–driven systemic inflammation, Dr. Sethi said.
The investigators surveyed 128 patients with a preoperative diagnosis of psoriasis identified from a single-center database of 9,073 bariatric surgeries performed between 2002 and 2013. A total of 86 patients completed the study, with 21 patients also having a preoperative diagnosis of PsA. Their mean preoperative weight was 288 pounds and preoperative body mass index 45.8 kg/m2. The average duration of psoriasis and PsA at the time of surgery was significant at 18.7 years, Dr. Sethi noted.
The mean time from surgery was 6.1 years, with a mean excess weight loss of 46.2% and total weight loss of 23.8%. Laparoscopic adjustable gastric banding was the most common surgery (91%), followed by Roux-en-Y bypass (7%).
In secondary analyses, a higher percent of excess weight loss at recent follow-up was significantly associated with an easing of psoriasis severity (59.5% vs. 43.5%; P = .046), while higher percent of excess weight loss at 1 year was associated with a trend in PsA improvement (55.4% vs. 43.8%; P = .47), Dr. Sethi said.
Easing of disease severity after surgery was associated with a higher rating of disease at the time of surgery (8.9 vs. 7.4; P less than .01) and older age at diagnosis (36.9 years vs. 25.9 years; P = .02), suggesting that these factors may be used to identify patients with a greater likelihood of improvement.
“Larger prospective studies are needed to further define the true effect of surgical weight loss on psoriasis and psoriatic arthritis,” she said at the meeting, presented by the Obesity Society and the American Society for Metabolic and Bariatric Surgery (ASMBS).
Session comoderator Dr. Peter T. Hallowell of the University of Virginia, Charlottesville, agreed that further studies are needed, but said the interesting thing is how bariatric surgery improves multiple problems.
“The results are pretty impressive with the moderate weight loss they got with laparoscopic gastric banding,” he said in an interview. “With gastric bypass or a sleeve, where we would expect greater weight loss and greater decrease in the inflammatory mediators, we may see an even greater improved outcome.”
A larger prospective study is being planned between New York University’s psoriasis and bariatric centers in about 60 patients with psoriasis and PsA undergoing bariatric surgery, mostly sleeve gastrectomy and gastric bypass, Dr. Sethi said in an interview.