ABDOMINAL BIOELECTRIC IMPEDANCE FOR FOLLOW-UP OF DIETERS: A PROSPECTIVE STUDY.

CONTEXT: Visceral adipose tissue (VAT) is a strong predictor of carbohydrate metabolism disorders. Abdominal bioelectrical impedance analysis (A-BIA) is a simple method for the measurement of VAT and is a promising tool in screening and follow-up of abdominal obesity. However the role of A-BIA in dieting individuals has not been evaluated adequately in longitudinal follow-up studies. OBJECTIVE: The aim of this study is to determine the role of A-BIA in identifying the changes in metabolic predictors after diet and/or exercise therapy. DESIGN: All patients who sought weight loss treatment underwent baseline assessment and were prescribed a program of diet. After a mean follow-up of 3.2 months, data were analyzed. SUBJECTS AND METHODS: Ultimately, 103 participants who reported adhering to the diet, enrolled to the study. We tested associations between changes in body composition measures and changes in laboratory measures using correlations and multivariate linear regression analysis. RESULTS: Mean loss of body weight was 3.4±2.8 kg. All but waist-to-hip ratio, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels changed significantly (p<0.001). Decreases in body weight, body mass index (BMI), and VAT level significantly correlated with decreases in fasting blood glucose, fasting insulin level, and HOMA-IR score (r=0.230-0.371). In multiple linear regression analysis changes in BMI and VAT significantly correlated with change in HOMA-IR score (F(7.93)=2.283, p=0.034, R2=0.147). CONCLUSION: Decreases in BMI and VAT, as determined by A-BIA, were predictors of changes in metabolic laboratory measures. A-BIA is useful for follow-up of patients receiving diet therapy for weight loss.

FAT DISTRIBUTION AND METABOLIC PROFILE IN SUBJECTS WITH HASHIMOTO'S THYROIDITIS.

CONTEXT: Previous studies have associated overt/subclinical hypothyroidism and obesity but have failed to confirm a causative relationship between them. Confusion is even more for subjects with Hashimoto's Thyroiditis (HT). OBJECTIVE: In this study, we aimed to evaluate the fat distribution and metabolic profile of subjects with euthyroid HT as well as to establish an appropriate cut-off level of TSH for the development of metabolic syndrome (Mets) in both groups. PATIENTS AND METHODS: All subjects were euthyroid whether under levothyroxine replacement or not. We recruited 301 volunteers (99 with HT and 202 without thyroid autoimmunity). Together with some metabolic variables, we measured the waist circumference, hip circumference, neck circumference manually; the total body fat with a body composition analyzer; and the visceral fat/trunk fat percentage via abdominal bioelectrical impedance analysis. RESULTS: A significant positive correlation was established between TSH levels and insulin, fasting plasma glucose, HOMA-IR and body mass index (r=0.28; p<0.001; r=0.27; p<0.05: r=0.32; p<0.001: r=0.13; p<0.05 respectively). The prevalence of Metabolic Syndrome (Mets) was comparable in HT and control groups (27.3% vs. 30.7%; p>0.05). The prevalence of Mets was similar when HT subjects using levothyroxine or HT subjects with accompanying thyroid nodules were taken into consideration. Similarly, anthropometric and metabolic parameters were similar in both the HT group and the control group.We were unable to establish the TSH cut-off level by ROC analysis with desired sensitivity and specificity (AUC: 0.563 with 95% C.I. p=0.35; standard error 0.76). CONCLUSIONS: Although weight gain is frequently encountered in subjects with HT, such subjects with thyroid function tests in the euthyroid range have a similar prevalence of Mets and similar metabolic and anthropometric measurements compared to subjects without autoimmunity.

Performance of abdominal bioelectrical impedance analysis and comparison with other known parameters in predicting the metabolic syndrome.

Although obesity is a powerful risk factor for metabolic syndrome (MetS) it is not present in all obese individuals. Increased visceral adipose tissue is the hallmark of this syndrome. In this cross sectional survey we aimed to use abdominal bioelectrical impedance analysis to measure the visceral adipose tissue (VAT) and trunk fat percentages (TF%) in the study population, correlate these findings with traditional anthropometric measures and biochemical parameters of metabolic syndrome and estimate a cut-off value of visceral fat for development of MetS. A total of 285 subjects were enrolled. VAT and TF% were measured by the AB-140 device via abdominal bioelectrical impedance analysis. Fat% was measured by a body composition analyzer (TBF-300). VAT was significantly positively correlated with body mass index, waist circumference, TF%, HOMA IR, fat percentage, fasting plasma glucose and triglycerides. Strongest correlations were between VAT and TF%, VAT and device measured waist circumference and between VAT and manual waist circumference (r=0.95, r=0.93, r=0.92 respectively). Correlations of VAT and TF% with metabolic parameters were significant but weak. The mean VAT and TF% in MetS (+) groups were significantly higher than patients in MetS (-) groups in both sexes. The areas under the ROC curves were 0.730 (95% CI: 0.661-0.791) for female VAT and 0.702 (95% CI: 0.654-0.749) for male VAT in predicting MetS which were similar to the areas under ROC curves calculated for device and manually measured waist circumference, HOMA IR and TF% in predicting MetS (p>0.05 for all comparisons). The accuracy of VAT and TF% for predicting MetS was not sufficient. From our results we can deduce that the performance of abdominal BIA in predicting MetS is weak but could be used in the follow-up of patients with obesity and/or MetS. This has to be confirmed in future studies.

Hepatitis B surface antigen seroconversion is associated with favourable long-term clinical outcomes during lamivudine treatment in HBeAg-negative chronic hepatitis B patients.

The aims of this study were to assess hepatitis B surface antigen (HBsAg) seroconversion and to determine its impact on the natural course of the disease in patients with HBeAg-negative chronic hepatitis B (CHB) during lamivudine (LMV) treatment. A total of 183 consecutive patients with HBeAg-negative CHB who were treated with LMV were included in the study. Data were retrospectively collected from outpatient visit charts. The primary endpoint was HBsAg seroconversion to anti-HBs. The secondary endpoint was to determine the development of cirrhosis. Loss of HBsAg was confirmed in 10 patients and seroconversion to anti-HBs in nine patients during LMV treatment or after its discontinuation. HBsAg seroconversion was achieved on-treatment in four patients after a median treatment duration of 30 months and off-treatment in the remaining five patients in a median 61 months after LMV discontinuation. The cumulative probability of HBsAg seroconversion increased from 0.6% at 1 year and 1.9% at 5 years to 21.5% at 10 years of LMV during and after LMV treatment. HBsAg clearance was preceded by undetectable serum hepatitis B virus (HBV) DNA. The majority of the patients responding to treatment had undetectable HBV DNA levels at 24 weeks of treatment. The cumulative probability of LMV resistance increased from 2.2% at 1 year to 37.3% at 5 years. No baseline parameter predicting either HBsAg seroconversion or the emergence of LMV resistance was identified. None of the patients with HBsAg seroconversion experienced virological breakthrough or disease progression during the follow-up period. These results indicate that HBsAg seroclearance can occur in patients with HBeAg-negative CHB under LMV therapy and predicts better clinical outcome.

Acute cytomegalovirus infection complicated by venous thrombosis in a renal transplant recipient.

We report a case of simultaneous acute cytomegalovirus infection and venous thrombosis in a renal transplant recipient. On posttransplant month 3, the patient started complaining of left leg pain and swelling. Tibiopopliteal and femoral deep venous thrombosis were confirmed by Doppler ultrasonography. A serological test for CMV ELISA was strongly positive for IgM antibodies. Acute CMV infection was diagnosed by serum quantitative DNA polymerase chain reaction. Genetic predisposing risk factors for thrombosis (eg, protein C and S deficiency, factor V Leiden and prothrombin G20210A mutations, and antithrombin III deficiency) were not present. Results of tests for anticardiolipin antibodies, lupus anticoagulant, and antinuclear antibodies were also negative. No other clinical or biologic risk factors for thrombosis were detected in the patient. The patient responded well to intravenous gancyclovir and low-molecular weight heparin therapy. He was discharged in good condition. Our observation suggests that acute CMV infection may be the cause of a thrombotic event in renal transplant recipients.