Visceral fat accumulation and postdexamethasone serum cortisol levels in patients with adrenal incidentaloma.

[adrenal incidentaloma]

Visceral fat is a significant cardiovascular risk factor . Because visceral fat has not been measured systematically in patients with adrenal incidentalomas , we have tested the hypothesis that visceral fat volume may be associated with cutoffs for serum cortisol levels post dexamethasone .This was a retrospective , cross-sectional study .The study was conducted at the Endocrine Investigation Unit , University Teaching Hospital .Seventy -three women and 52 men diagnosed with adrenal incidentalomas and 9 patients with overt Cushing 's syndrome participated in this study .The following was measured for serum cortisol level after dexamethasone suppression and visceral fat ratios : visceral-subcutaneous (V :S ) and visceral-total volume (V :TV ) measured by computed tomography .Sixty -eight patients with a postdexamethasone serum cortisol greater than 1 .8 Î¼g /dL (50 nmol /L ) showed a significantly higher mean V :S and V :TV fat ratio compared with those whose serum cortisol was less than 1 .8 Î¼g /dL : women , lnV :S , -0 .45 vs -0 .69 [mean difference 0 .24 (95 % confidence interval [CI ] 0 .08 -0 .41 ); P = .004 ] and V :TV , 0 .39 vs 0 .34 [mean difference 0 .05 (95 % CI 0 .02 -0 .09 ); P = .004 ]; men , lnV :S , 0 .64 vs 0 .29 [mean difference 0 .35 95 % CI 0 .08 -0 .63 ); P = .01 ] and V :TV , 0 .65 vs 0 .57 [mean difference 0 .08 (95 % CI 0 .02 -0 .14 ); P = .02 ]. By ANOVA and post hoc analysis (Fisher 's least significant differences ), there was no difference in fat ratios between the postdexamethasone serum cortisol groups [1 .8 -2 .9 Î¼g /dL (50 -82 nmol /L ), 3 .0 -5 .0 Î¼g /dL (83 -137 nmol /L ), > 5 .0 Î¼g /dL (>138 nmol /L ) and Cushing 's syndrome (mean V :TV : 0 .38 , 0 .40 , 0 .40 , 0 .41 , respectively )], but they all differed significantly from the less than the 1 .8 -Î¼g /dL group (V :TV : 0 .34 , P = .03 ).Visceral fat is increased in patients with adrenal incidentalomas and a postdexamethasone serum cortisol of greater than 1 .8 Î¼g /dL and is similar to that found in patients with overt Cushing 's syndrome .