Gallbladder Volume (Comparison of Diabetics and Controls)

Diabetics are known to have an increasedprevalence of gallstones. The aim of this study was toinvestigate whether diabetics have increased gallbladdervolumes that would predispose to stasis, nucleation of cholesterol crystals, and gallstoneformation. The gallbladder volume of 271 diabeticsubjects and 277 controls was determined by ultrasoundusing the ellipse formula. Gallbladder volume was alsodetermined by the sum of the cylinders method in 143 caseswith a strong correlation (r = 0.89) between the twomethods. Using analysis of variance, gallbladder volumewas influenced by both diabetic type (NIDDM 33.68 cm³, IDDM = 26.84 cm³,controls 29.05 cm³; P = 0.018) and thepresence of gallstones (gallstones 32.04 cm³,no gallstones 27.58 cm³; P = 0.018). Thevariation in gallbladder volume between NIDDM, IDDM, andcontrol subjects was influenced by the presence ofgallstones (P = 0.024, interaction term from ANOVA).Significant differences (P < 0.001) were only foundbetween NIDDM vs IDDM and NIDDM vs control in thenongallstone group (NIDDM 34.33 cm³, IDDM = 25.08cm³, control = 25.17 cm³). Maleshad significantly larger gallbladder volumes thanfemales: 31.98 cm³ vs 27.74 cm³ (P= 0.023). After the inclusion of BMI, HDL cholesterol, triglyceride, and age in a statistical modelwith gender and diabetic type in those withoutgallstones, significant differences were still foundbetween NIDDM and IDDM (P = 0.013) and NIDDM andcontrols (P = 0.005), demonstrating that NIDDM is anindependent predictor for increased gallbladdervolume.