Are patients with cirrhosis "glucose resistant"?

Prevalence and determinants of diabetes mellitus among Iranian patients with chronic liver disease

BACKGROUND: Alterations in carbohydrate metabolism are frequently observed in cirrhosis. We conducted this study to define the prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in Iranian patients with chronic liver disease (CLD), and explore the factors associated with DM in these patients. METHODS: One hundred and eighty-five patients with CLD were enrolled into the study. Fasting plasma glucose and two-hour plasma glucose were measured in patients' sera. DM and IGT were diagnosed according to the latest American Diabetes Association criteria. RESULTS: The subjects included 42 inactive HBV carriers with a mean age of 42.2 +/- 12.0 years, 102 patients with HBV or HCV chronic hepatitis with a mean age of 41.2 +/- 10.9 years, and 41 cirrhotic patients with a mean age of 52.1 +/- 11.4 years. DM and IGT were diagnosed in 40 (21.6%) and 21 (11.4%) patients, respectively. Univariate analysis showed that age (P = 0.000), CLD status (P = 0.000), history of hypertension (P = 0.007), family history of DM (P = 0.000), and body mass index (BMI) (P = 0.009) were associated with DM. Using Multivariate analysis, age (OR = 4.7, 95%CI: 1.8-12.2), family history of DM (OR = 6.6, 95%CI: 2.6-17.6), chronic hepatitis (OR = 11.6, 95%CI: 2.9-45.4), and cirrhosis (OR = 6.5, 95%CI: 2.4-17.4) remained as the factors independently associated with DM. When patients with cirrhosis and chronic hepatitis were analyzed separately, higher Child-Pugh's score in cirrhotic patients (OR = 9.6, 95%CI: 1.0-88.4) and older age (OR = 7.2, 95%CI: 1.0-49.1), higher fibrosis score (OR = 59.5, 95%CI: 2.9-1211.3/ OR = 11.9, 95%CI: 1.0-132.2), and higher BMI (OR = 30.3, 95%CI: 3.0-306.7) in patients with chronic hepatitis were found to be associated with higher prevalence of DM. CONCLUSIONS: Our findings indicate that patients with cirrhosis and chronic hepatitis are at the increased risk of DM occurrence. Older age, severe liver disease, and obesity were associated with DM in these patients.

Elevated insulin, proinsulin and insulin-like growth factor-binding protein-1 in liver disease

Insulin-like growth factor-binding protein-1 (IGFBP-1) is one of six soluble binding proteins that regulate the actions of the insulin-like growth factors (IGFs). Liver is the major source of IGFBP-1 in non-pregnant humans. In normal physiology, IGFBP-1 transcription is potently inhibited by insulin and serum levels are limited by a rapid clearance rate. Elevated levels of IGFBP-1 in liver disease have been attributed to insulin resistance; however, the relationships between these analytes have not been defined. We studied insulin, proinsulin and IGFBP-1 in normal subjects (NL, N=47, 43+/-12 yr), cirrhosis (CIR, N=29, 54+/-14 yr), hepatocellular carcinoma (HCC, N=42, 61+/-11 yr), and other liver tumors (TUM, N=8, 60+/-17 yr). All three analytes were significantly increased in liver disease (mean+/-SEM; p-values relative to normals): IGFBP-1 (NL 24+/-4 ng/ml; CIR 235+/-53, p<0.0001; HCC 505+/-105, p<0.0001; TUM 118+/-36, p<0.0001), insulin (NL 72+/-4 pM; CIR 261+/-62, p<0.0002; HCC 180+/-25, p<0.0001; TUM 189+/-58, p<0.0001), proinsulin (NL 6.5+/-0.7 pM; CIR 36.8+/-7.7, p<0.0001; HCC 26.2+/-3.8, p<0.0001; TUM 32.1+/-9.7, p<0.0001). The ratio of proinsulin to insulin was also significantly elevated in liver disease. A typical curvilinear inverse relationship of insulin and IGFBP-1 was observed, but was shifted several fold higher for the liver disease groups. Our results demonstrate that insulin and proinsulin are elevated in liver disease. However, these elevations are paradoxically accompanied by elevated IGFBP-1 levels, indicating disruption of normal regulatory mechanisms. IGFBP-1 is postulated to play a dynamic role in metabolic substrate utilization via regulation of free IGF. Therefore, inappropriate elevation of IGFBP-1 could play an important role in the metabolic disturbances associated with liver disease.

Impaired nonoxidative glucose metabolism in patients with liver cirrhosis: effects of two insulin doses

Glucose intolerance is encountered in the majority of cirrhotic patients. This alteration has been attributed to a defective insulin-mediated glucose uptake in peripheral tissue, where nonoxidative glucose disposal seems to be chiefly impaired. To further investigate insulin action under euglycemic conditions, we studied how physiological (100 microU/mL) and pharmacological (1,000 microU/mL) plasma insulin concentrations affect whole-body insulin-mediated glucose uptake, as well as oxidative and nonoxidative glucose disposal, in cirrhotic patients and controls. To this aim, a sequential two-step insulin euglycemic clamp combined with indirect calorimetry was performed in eight cirrhotic patients and six control subjects. During the first step of the clamp, total glucose uptake was reduced by 40% in cirrhotic patients versus controls (4.42 +/- 1.39 v 7.63 +/- 1.60 mg/kg/min, P = .002). By increasing insulin to pharmacological levels, glucose disposal increased in both groups. However, the maximum rate of glucose metabolism achieved in cirrhotic patients was lower than in controls at all times (10.29 +/- 2.04 v 12.82 +/- 0.51 mg/kg/min, P = .012). Glucose oxidation was lower in cirrhotics in the basal state, but similar in both groups during insulin/glucose infusion. On the other hand, the reduced nonoxidative glucose disposal observed in cirrhotic patients was not normalized even by increasing insulin to pharmacological levels. In conclusion, in liver cirrhosis a reduced insulin sensitivity is associated with a reduced insulin responsiveness that is mainly caused by defective nonoxidative glucose disposal.