Weight loss and achievement of minimal disease activity in patients with psoriatic arthritis starting treatment with tumour necrosis factor α blockers

OBJECTIVES: To evaluate prospectively the effect of weight loss on the achievement of minimal disease activity (MDA) in overweight/obese patients with psoriatic arthritis (PsA) starting treatment with tumour necrosis factor α (TNFα) blockers. METHODS: Among subjects with PsA starting treatment with TNFα blockers, 138 overweight/obese patients received a concomitant dietary intervention (69 a hypocaloric diet (HD) and 69 a free-managed diet (FD)). Changes in metabolic variables were measured and a complete clinical rheumatological evaluation was made in all patients at baseline and after a 6-month follow-up to define the achievement of MDA. RESULTS: 126 subjects completed the study. MDA was more often achieved by HD than by FD subjects (HR=1.85, 95% CI 1.019 to 3.345, p=0.043). A diet was successful (≥5% weight loss) in 74 (58.7%) patients. Regardless of the type of diet, after 6 months of treatment with TNFα blockers, ≥5% of weight loss was a predictor of the achievement of MDA (OR=4.20, 95% CI 1.82 to 9.66, p<0.001). For increasing weight-loss categories (<5%, 5-10%, >10%), MDA was achieved by 23.1%, 44.8% and 59.5%, respectively. A higher rate of MDA achievement was found in subjects with 5-10% (OR=3.75, 95% CI 1.36 to 10.36, p=0.011) and in those with >10% (OR=6.67, 95% CI 2.41 to 18.41, p<0.001) weight loss in comparison with those with <5% weight loss. CONCLUSIONS: Regardless of the type of diet, a successful weight loss (≥5% from baseline values) is associated with a higher rate of achievement of MDA in overweight/obese patients with PsA who start treatment with TNFα blockers.