Fig. 2. Residual-residual plots. Each plot shows the relationship between REE and log leptin after both have been adjusted for the effects of FFM using linear regression. The adjusted variables are labeled "Residual REE" and "Residual log leptin," respectively.

a.In males, a positive linear relationship was observed between log leptin and REE in control subjects, after adjusting for FFM (see Table 3 for corresponding analysis; regression coefficient=1.01). This relationship was not observed in SCD patients.

b.In females, no consistent relationship between log leptin and REE was observed after adjusting for FFM, though REE was higher on average in SCD females those in control females (see Table 3 for corresponding analysis; regression coefficient=0.901).