Energy-restricted, n-3 polyunsaturated fatty acids-rich diet improves the clinical response to immuno-modulating drugs in obese patients with plaque-type psoriasis: A randomized control clinical trial

摘要

Low-grade systemic inflammation associated with obesity may worsen the clinical course of psoriasis. This study aimed to assess the effectiveness of an energy-restricted diet, enriched in n-3 polyunsaturated fatty acids (PUFAs) and poor in n-6 PUFAs, on metabolic markers and clinical outcome of obese patients with psoriasis. Methods: Forty-four obese patients with mild-to-severe plaque-type psoriasis treated with immuno-suppressive drugs were randomized to assume for six months either their usual diet or an energy-restricted diet (20kcal/kg/ideal body weight/day) enriched of n-3 PUFAs (average 2.6g/d). All patients continued their immuno-modulating therapy throughout the study. Results: At 3 and 6 months, a significant clinical improvement was observed in patients assuming the low-calorie high n-3 PUFAs diet respect to controls. Specifically Psoriasis Area Score Index (7.7±3.7, 5.3±4.3 and 2.6±3.0, respectively; p<0.05), itch scores (15.4±13.5, 12.3±12.1 and 1.8±5.9, respectively; p<0.05) and Dermatological Life Quality Index (19.5±1.9, 11.4±3.5 and 5.1±1.6; respectively, p<0.05) all decreased respect to baseline. In these subjects but not in controls, a significant decrease in body weight (93.8±10.1, 85.8±11.4 and 83.1±12.1kg, respectively; p<0.05), waist circumference (112.7±7.2, 106.1±10.3 and 101.9±10.4cm; p<0.05), serum triglycerides (141.8±51.1, 100.5±26.6 and 90.2±34.5mg/dL; respectively, p<0.05), serum total cholesterol (198.3±31.7, 171.4±29.0 and 176.5±20.5mg/dL; respectively, p<0.05) and n-6-3 ratio intake also occurred (5.1±0.9, 2.0±0.9 and 2.3±1.1; respectively, p<0.05). Conclusions: In obese psoriatic patients, an energy-restricted diet designed to increase n-3 and reduce n-6 PUFAs, ameliorated the metabolic profile and, by increasing the response to immuno-modulating therapy, improved the clinical outcomes of the disease (ClinicalTrials.gov identifier: NCT01876875).