BMI categories
When SSc patients were subdivided by BMI categories, some meaningful differences emerged (Table 3). As expected, leptin (Figure 1) and visfatin levels were significantly higher in obese than in other BMI classes (p=0.0001 and p=0.002 , respectively), while no significant changes were observed for resistin. Obese SSc patients also had the highest serum levels of IL-17A (p=0.01 ), IL-2 (p=0.001 ) and IL-10 (p=0.01 ). Adiponectin levels did not significantly change among the BMI subgroups, but the leptin/adiponectin ratio, a functional biomarker of adipose tissue inflammation, was significantly higher in obese patients (p=0.0001 ). A striking finding was the increased TNFα levels observed in underweight SSc patients. The latter had significantly higher TNFα levels (p=0.01 ) than the other BMI classes (Table 3, Figure 2). IL-17A, leptin, and visfatin levels were found to be positively correlated, and TNFα negatively, with increasing BMI values (table 4). BMI was also correlated with ESR, CRP, triglycerides and cholesterol levels (Table 4).