HMGB1 and obesity due to melanocortin 4 receptor deficiency: High levels of HMGB1 have also been found in patients with type 2 diabetes, obesity and Inflammatory bowel disease (IBD) (Wang et al. 2016; Guzmán-Ruiz et al. 2021; Hu et al. 2015), which are common comorbidities of PsA.