Relationship between changes in serum leptin levels and blood pressure after weight loss

本研究旨在探讨102例中度肥胖女性(BMI，29.5±0.5 kg/m^2；年龄，47.0±0.9)3个月内血压变化与血清瘦素和胰岛素水平的关系。高血压组(n=31)和正常血压组(n=71)在年龄、脂肪质量、HOMA、Σ胰岛素抵抗指数、血浆肾素活性和24小时去甲肾上腺素排泄量(24hU-NE)方面均无差异，但基础瘦素水平在高血压组显著高于正常血压组。经过3个月的减肥治疗，两组患者的腹脂、血清瘦素和Σ胰岛素抵抗指数均显著下降。SBP、DBP仅在高血压组显著降低，而在NT组未见明显下降。24小时U-NE仅在羟色胺组显著降低。两组瘦素水平的变化分别与减肥后Σ胰岛素抵抗指数和HOMA的变化显著相关。最后，仅在高血压组，瘦素的变化与平均血压(MBP)的变化之间存在统计学上的显著正相关。多元回归分析显示，所有受试者的血压变化与24小时U-NE、Σ、IRI和HOMA的变化独立相关。然而，仅在HT组，即使调整了腹脂总量、24小时U-NE和Σ胰岛素抵抗指数(均以基线值的百分比表示)，血压的变化也与瘦素水平的变化呈统计学正相关。提示瘦素可能在肥胖性高血压的病理生理过程中起一定作用。此外，饱和脂肪酸摄入量与Σ胰岛素抵抗指数呈显著正相关。这些结果表明，饱和脂肪酸的摄入可能会增加胰岛素抵抗。

The aims of this study to clarify the relationship between changes in blood pressure and either the serum leptin level or the insulin levels in 102 moderately obese females (BMI, 29.5±0.5kg/m^2; age, 47.0±0.9) during a 3month period. No differences in age, fat-mass, HOMA, ΣIRI, plasma renin activity (PRA) or 24h norepinephrine excretion (24hU-NE) were observed between the hypertensive (HT) group (n=31) and normotensive (NT) group (n=71) before weight loss, but the basal leptin was significantly higher in the HT than in the NT group. After a 3month weight reduction program, the total abdominal fat serum leptin and ΣIRI significantly decreased in both groups. The SBP, DBP significantly decreased only in the HT but not in the NT group. The 24h U-NE significantly decreased only the HT group. The changes in the leptin level were significantly correlated with the changes in both ΣIRI and HOMA after weight loss in the two groups, respectively. Finally, a statistically significant positive correlation was observed between the change in the leptin and the changes in the mean blood pressure (MBP) only in the HT group. Multiple regression analysis revealed that the changes in MBP were independently associated with the changes in 24h U-NE and the changes in either ΣIRI and HOMA in all subjects. However, a statistically positive correlation was observed between the changes in MBP and the changes in leptin levels even adjusting for the total abdominal fat, 24h U-NE and ΣIRI (both expressed as a percentage of the baseline value) only in the HT group. These results suggest that leptin may play a role in the pathophysiology of obese hypertension. In addition, a significant positive correlation was observed between the saturated fatty acid intake and ΣIRI. These results suggest that saturated fatty acid intake may increased insulin resistance.