Ultrasonographic assessment of lipodystrophy in HIV-1-infected patients

Interleukin-17 regulates visceral obesity in HIV-1-infected patients

OBJECTIVE

The aim of the study was to evaluate the interleukin-17 (IL-17) plasma level in HIV-1-infected patients and its relation to central obesity.

METHODS

Eighty-four HIV-1-infected patients [42 with visceral obesity (group A) and 42 without visceral obesity (group B)] and 46 HIV-negative subjects [23 with visceral obesity (group C) and 23 without visceral obesity (group D)] were enrolled in the study. Sonographic measurements of perirenal fat diameter/body mass index (PRFD/BMI) were used to assess visceral adipose tissue thickness.

RESULTS

HIV-1-infected patients had higher plasma levels of IL-17 than HIV-negative subjects [837.8 ± 260 pg/mL (mean ± standard deviation) vs. 395.3 ± 138.6 pg/mL, respectively; P<0.001]. Furthermore, HIV-1-infected patients with a diagnosis of visceral obesity had lower levels of IL-17 than HIV-infected lean patients (756.9 ± 282.9 pg/mL vs. 918.7 ± 208.4 pg/mL, respectively; P<0.01). IL-17 (r= -0.21; P=0.03) and waist circumference (r=0.48; P<0.001) were significantly associated with visceral adipose tissue thickness. A negative correlation of IL-17 (r= -0.23; P<0.001) with PRFD/BMI was found.

CONCLUSIONS

This study suggests a linear negative association between IL-17 and visceral adipose tissue thickness.

A Comparison of Sonographic Assessments and Clinical Questionnaire in the Diagnosis of HIV-Associated Lipodystrophy

The study evaluated the use of sonographic measurements as an alternative to assessments based on clinical or other imaging techniques for the diagnosis of body-fat abnormalities. The study enrolled 179 HIV-infected patients, 81 (45.3%) of them diagnosed as lipodystrophy (LD)-positive based on a clinical standard questionnaire. Association between clinical LD and sonographic measurements of face, right upper limb, subcutaneous abdomen, and visceral compartments was evaluated by multiple logistic regression. The predicted probability of the logistic model was 0.64, corresponding to a maximum sensitivity of 69.1% (58%-79%), a specificity of 94.9% (88%-98%), and to positive and negative predictive values of 92% (82%-97%) and 79% (70%-86%), respectively. Kappa measure of concordance was 65% (54%-77%). Low sensitivity poses a problem for the use of sonography to detect LD in the clinical routine as a single exam, speaking in favor of the combined use of clinical and sonographic measurements over time.

Ultrasound-assessed perirenal fat is related to increased ophthalmic artery resistance index in HIV-1 patients

Background

The introduction of highly active antiretroviral therapy (HAART) has dramatically changed the prognosis of human immunodeficiency virus (HIV) infection, with a significant decline in morbidity and mortality.

Changes in body fat distribution are a common finding in individuals with HIV infection being treated with antiretrovirals, and this condition (collectively termed lipodystrophy syndrome) is associated with depletion of subcutaneous fat, increased triglycerides and insulin resistance. Obesity, particularly visceral obesity, is associated with increased risk of cardiovascular disease. Therefore, estimating visceral fat distribution is important in identifying subjects at high risk for cardiovascular disease.

The aim of our study was to evaluate whether perirenal fat thickness (PRFT), a parameter of central obesity, is related to ophthalmic artery resistance index (OARI), an index of occlusive carotid artery disease in HIV-1 infected patients.

Methods

We enrolled 88 consecutive HIV-1-infected patients receiving highly active antiretroviral therapy for more than 12 months, in a prospective cohort study. Echographically measured PRFT and OARI, as well as serum metabolic parameters, were evaluated. PRFT and OARI were measured by 3.75 MHz convex and 7.5 MHz linear probe, respectively.

Results

The means of PRFT and OARI in HIV-1-infected patients with visceral obesity was considerably higher than in patients without it (p < 0.0001 and p < 0.001, respectively). Using the average OARI as the dependent variable, total serum cholesterol level, HDL, triglycerides, glycemia, sex, blood pressure, age and PRFT were independent factors associated with OARI. A PRFT of 6.1 mm was the most discriminatory value for predicting an OARI > 0.74 (sensitivity 78.9%, specificity 82.8%).

Conclusions

Our data indicate that ultrasound assessment of PRFT may have potential as a marker of increased endothelial damage with specific involvement of the ocular vascular region in HIV-1-infected patients.

Sonographically measured perirenal fat thickness: an early predictor of atherosclerosis in HIV-1-infected patients receiving highly active antiretroviral therapy?

PURPOSE

The aim of our study was to evaluate whether perirenal fat thickness (PRFT), a parameter of central obesity, is related to carotid intima-media thickness (IMT), an index of atherosclerosis in human immunodeficiency virus (HIV)-1-infected patients.

METHODS

We enrolled 70 consecutive HIV-1-infected patients receiving highly active antiretroviral therapy for more than 12 months, in a prospective cohort study. Sonographically measured PRFT and carotid IMT, as well as serum metabolic parameters, were evaluated. PRFT and IMT were measured using 3.75-MHz convex and 7.5-MHz linear probes, respectively.

RESULTS

The mean PRFT and IMT in HIV-1-infected patients with visceral obesity was significantly greater than those in patients without it (p < 0.0001 and p < 0.01, respectively). Using the average IMT as the dependent variable in regression analysis, PRFT was an independent factor associated with carotid IMT (p < 0.05). A PRFT of 6.4 mm was the most discriminatory value for predicting an IMT >or= 0.9 mm (sensitivity 83.3%, specificity 83.9%). Subjects with visceral obesity had a progressively increasing carotid IMT on the 12-month measurement (p < 0.05).

CONCLUSION

Our data demonstrated that PRFT measurement could be used as an early predictor of IMT increase in HIV-1-infected patients receiving highly active antiretroviral therapy.

Association of visceral adiposity with increased intrarenal artery resistive index in HIV-1-infected patients receiving highly active antiretroviral therapy

PURPOSE

The aim of our study was to evaluate whether perirenal fat thickness (PRFT), a parameter of central obesity, is related to kidney function and intrarenal artery resistive index (IARI) in human immunodeficiency virus (HIV)-1-infected patients.

MATERIALS AND METHODS

We enrolled 102 consecutive HIV-1-infected patients receiving highly active antiretroviral therapy for more than 12 months in a prospective cohort study. Echographically, the PRFT and IARI were measured and the serum metabolic parameters were evaluated. PRFT and IARI were measured using a 3.75 MHz convex linear probe.

RESULTS

The mean of PRFT and IARI in HIV-1-infected patients with visceral obesity was considerably higher than that in patients without it (P <0.001 and <0.01, respectively). Using the average IARI as the dependent variable, age (odds ratio, 1.07; 95% confidence interval [CI], 1.01-1.14; P < 0.5) and PRFT (odds ratio, 1.28; 95% CI, 1.08P-1.51; P<0.01) were independent factors associated with IARI.

CONCLUSION

Our data indicate that ultrasonographic assessment of PRFT may have a potential to be a marker of increased endothelial damage with specific involvement of the renal vascular district in HIV-1-infected patients.