Such results by single studies have been confirmed in a large meta-analysis including 54 studies and 19.372 patients, which showed that obesity is associated with 60% higher odds of inadequate response to anti-TNF treatment as compared to normal BMI; for each unit increment of BMI, there is an augmentation in odds of failure by 6.5% [137]. Here, TNF is linked to obesity due to melanocortin 4 receptor deficiency.