Metabolism Unit, Instituto Estadual de Diabetes e Endocrinologia, Rio de Janeiro and Catholic University, Rio de Janeiro, Brazil.
Diabetol Metab Syndr. 2012 Aug 31;4(1):40. doi: 10.1186/1758-5996-4-40.
Familial partial lipodystrophies (FPLD) are clinically heterogeneous disorders characterized by selective loss of adipose tissue, insulin resistance and metabolic complications. Until genetic studies become available for clinical practice, clinical suspicion and pattern of fat loss are the only parameters leading clinicians to consider the diagnosis. The objective of this study was to compare body composition by dual energy X-ray absorptiometry (DXA) in patients with FPLD and control subjects, aiming to find objective variables for evaluation of FPLD.
Eighteen female patients with partial lipodystrophy phenotype and 16 healthy controls, matched for body mass index, sex and age were studied. All participants had body fat distribution evaluated by DXA measures. Fasting blood samples were obtained for evaluation of plasma leptin, lipid profile and inflammatory markers. Genetic studies were carried out on the 18 patients selected that were included for statistical analysis. Thirteen women confirmed diagnosis of Dunnigan-type FPLD (FPLD2).
DXA revealed a marked decrease in truncal fat and 3 folds decrease in limbs fat percentage in FPLD2 patients (p <0.001). Comparative analysis showed that ratio between trunk and lower limbs fat mass, characterized as Fat Mass Ratio (FMR), had a greater value in FLPD2 group (1.86 ± 0.43 vs controls 0.93 ± 0.10; p <0.001) and a improved accuracy for evaluating FPLD2 with a cut-off point of 1.2. Furthermore, affected women showed hypoleptinemia (FLPD2 4.9 ± 2.0 vs controls 18.2 ± 6.8; p <0.001), insulin resistance and a more aggressive lipid profile.
In this study, assessment of body fat distribution by DXA permitted an objective characterization of FLPD2. A consistent pattern with marked fat reduction of lower body was observed in affected patients. To our knowledge this is the first time that cut-off values of objective variables were proposed for evaluation of FPLD2.
家族性部分脂肪营养不良症（FPLD）是一种临床表现具有异质性的疾病，其特征为选择性的脂肪组织丢失、胰岛素抵抗和代谢并发症。在基因检测能够应用于临床实践之前，临床怀疑和脂肪丢失模式是唯一能使临床医生考虑该诊断的参数。本研究的目的是通过双能 X 射线吸收法（DXA）比较 FPLD 患者和对照组的身体成分，旨在寻找评估 FPLD 的客观变量。
研究了 18 名具有部分脂肪营养不良表型的女性患者和 16 名年龄、性别和体重指数相匹配的健康对照者。所有参与者均通过 DXA 测量评估体脂分布。采集空腹血样，用于评估血浆瘦素、血脂谱和炎症标志物。对选择的 18 名患者进行了基因研究，这些患者被纳入了统计分析。13 名女性被确诊为 Dunnigan 型 FPLD（FPLD2）。
DXA 显示 FPLD2 患者的躯干脂肪明显减少，四肢脂肪百分比减少了 3 倍（p<0.001）。对比分析显示，躯干和下肢脂肪量的比值，即脂肪量比（FMR），在 FPLD2 组中具有更大的值（1.86±0.43 与对照组 0.93±0.10；p<0.001），且用 1.2 作为截断值评估 FPLD2 具有更高的准确性。此外，受影响的女性表现出低瘦素血症（FPLD2 4.9±2.0 与对照组 18.2±6.8；p<0.001）、胰岛素抵抗和更具侵袭性的血脂谱。
在这项研究中，通过 DXA 评估体脂分布可客观地描述 FPLD2。受影响的患者下肢脂肪明显减少，表现出一致的模式。据我们所知，这是首次提出用于评估 FPLD2 的客观变量的截断值。
