GENEVA – according to a systematic review and meta-analysis presented by Ching-Chi Chi, MD, at the annual congress of the European Academy of Dermatology and Venereology.
A plausible mechanism of benefit exists for these findings: “Fat tissue is known to be an endocrine organ that produces inflammatory cytokines, such as tumor necrosis factor. Reduce the amount of fat tissue and you reduce inflammation,” explained Dr. Chi, professor of dermatology at Chang Gung University in Taoyuan, Taiwan.
His meta-analysis of 10 randomized, controlled trials totaled 1,163 patients with psoriasis, all with disease sufficiently severe that they were on systemic therapy. Six trials tested dietary interventions, one used a combined diet and exercise program, another involved walking for exercise coupled with continuous health education, and two studies used educational programs promoting healthy lifestyle without coupling to a diet or exercise program.Among the key findings in the meta-analysis: Participation in dietary interventions provided obese psoriasis patients with a 66% increased likelihood of achieving a PASI 75 response at week 24, compared with controls, with a number needed to treat of 3. These low-calorie diets were typically rigorous, the dermatologist noted. For example, one entailed a food intake of 1,000 kcal/day or less, while another restricted intake by 500 kcal/day less than a patient’s calculated resting energy expenditure.
Also, participants in the dietary intervention studies averaged a 14.4-point improvement from baseline in Dermatologic Life Quality Index (DLQI) scores at week 24 versus a 2.2-point improvement in controls. Researchers consider a 5-point or greater improvement in the DLQI clinically meaningful.
A combined diet and exercise program resulted in a 45% increased likelihood that obese psoriasis patients would achieve a PASI 50 response at week 16, with a number needed to treat of 7. There was a trend in the active treatment arm for higher PASI 75 and PASI 100 responses than in controls as well, but it wasn’t statistically significant.
The one randomized trial of a walking exercise program coupled with continuous health education demonstrated a significant reduction in the rate of psoriasis flares, compared with controls, over a 3-year period.
In contrast, the studies of educational programs promoting a healthy lifestyle without an associated dietary or physical activity intervention failed to show a reduction in PASI scores.
Dr. Chi reported no financial conflicts of interest regarding his study, which was funded by Chang Gung Memorial Hospital.
SOURCE: Chi C. EADV 2017.