Department of Medicine, McGill University Hospital Center, Montreal, Canada.
HIV Med. 2014 Feb;15(2):98-107. doi: 10.1111/hiv.12085. Epub 2013 Sep 22.
The accuracy of the use of anthropometrics to quantify visceral adipose tissue (VAT) in treated HIV-infected patients is unknown. We evaluated the predictive accuracy of waist circumference (WC) with and without dual-energy X-ray absorptiometry (DXA)-derived trunk : limb fat ratio [fat mass ratio (FMR)] as surrogates for VAT determined using computerized axial tomography (CT-determined VAT).
We performed a retrospective cohort analysis of treated HIV-infected male patients followed at the Modena HIV Clinic. We developed prediction equations for VAT using linear regression analysis and Spearman correlations. Receiver operating characteristic (ROC) analysis evaluated the accuracy of WC alone or with FMR at discrete VAT thresholds.
The 1500 Caucasian male patients had a median age of 45 years, body mass index (BMI) of 24, WC of 87 cm, VAT area of 127 cm(2) and body fat percentage of 14%. The correlation between WC-predicted VAT and CT-VAT was 0.613, and this increased significantly if FMR was added. The WC-associated R(2) of 0.35 increased to 0.51 if the prediction equation included WC plus FMR. The area under the ROC curve (AUC) using WC was 0.795-0.820 at all VAT thresholds. The positive predictive value (PPV) and negative predictive value (NPV) changed reciprocally at CT-VAT thresholds from 75 to 200 cm(2) and ranged from 0.72 to 0.74, respectively, at a representative VAT of 125 cm(2). Adding the FMR to the predictive equations increased the AUC in the range of 0.854-0.889 with the PPV and NPV increasing minimally, ranging from 0.780 to 0.821. Limits of precision were wide, especially at the highest CT-VAT levels, and varied from 24 to 68 cm(2).
WC is a limited surrogate for CT-VAT in this population and DXA-derived parameters do not improve performance indices to a clinically relevant level. These findings should inform the applicability of WC to predict VAT in treated HIV-infected male patients.
利用人体测量学来量化接受治疗的 HIV 感染者内脏脂肪组织（VAT）的准确性尚不清楚。我们评估了腰围（WC）和双能 X 射线吸收法（DXA）衍生的躯干：肢体脂肪比[脂肪质量比（FMR）]作为计算机轴向断层扫描（CT 确定的 VAT）确定的 VAT 的替代指标的预测准确性。
我们对在摩德纳 HIV 诊所接受治疗的 HIV 感染男性患者进行了回顾性队列分析。我们使用线性回归分析和 Spearman 相关性对 VAT 进行了预测方程的开发。接受者操作特征（ROC）分析评估了 WC 单独或与 FMR 在离散 VAT 阈值处的准确性。
1500 名白种男性患者的中位年龄为 45 岁，体重指数（BMI）为 24，WC 为 87cm，VAT 面积为 127cm²，体脂百分比为 14%。WC 预测的 VAT 与 CT-VAT 之间的相关性为 0.613，如果添加 FMR，则相关性显著增加。如果预测方程包含 WC 和 FMR，则与 WC 相关的 R²从 0.35 增加到 0.51。使用 WC 的 ROC 曲线下面积（AUC）在所有 VAT 阈值下为 0.795-0.820。在 CT-VAT 阈值从 75 到 200cm²范围内，阳性预测值（PPV）和阴性预测值（NPV）相互变化，在代表性的 125cm²的 VAT 处分别为 0.72 到 0.74。在预测方程中添加 FMR，AUC 的范围为 0.854-0.889，PPV 和 NPV 略有增加，范围从 0.780 到 0.821。精度限制很宽，尤其是在最高的 CT-VAT 水平，范围从 24 到 68cm²。
在该人群中，WC 是 CT-VAT 的有限替代指标，DXA 衍生参数并不能将性能指标提高到临床相关水平。这些发现应该告知 WC 在预测接受治疗的 HIV 感染男性患者 VAT 中的适用性。
