Department of Endocrine and Medical Sciences, University of Genova, Viale Benedetto XV 6, 16132, Genoa, Italy.
Pituitary. 2012 Jun;15(2):215-21. doi: 10.1007/s11102-011-0313-4.
The objective of this study is to assess the secretory pattern of GH after Oral Glucose Tolerance Test (OGTT) or day-curve (DC), in relation with IGF-I and to evaluate the influence of therapy on OGTT. A retrospective analysis in 279 OGTTs performed in 93 acromegalic patients in our unit from January 1988 to December 2005, in 77 patients also DC data were retrived. GH concentration was evaluated by 3 different systems (RIA, IRMA and chemiluminescence assays), and IGF-I by two RIAs. About 12% of OGTT samples were discordant with the baseline, while discordance between nadir and 120th minute was much lower (5%), with all discordant values, except one, near the cut-off lines. Correlation between DC and OGTT data was around 0.99 among all values, discordance rate between nadir and minimum DC was much lower than that with mean DC. In almost 80% of cases there was a complete concordance between OGTT and DC results, and in about 30% IGF-I was discordant with GH. Correlation analysis between IGF-I and GH was highest with DC data and lowest with OGTT baseline (T0). Considering different treatments discrepancy rates between GH and IGF-I were comparable. The best GH parameter is the minimum GH DC, although in the clinical practice the evaluation of OGTT GH in association with IGF-I is the most practical approach. In this case, the basal and T120 GH values can replace multiple sampling. Different treatment modalities do not influence the discordance rate between GH and IGF-I.
本研究旨在评估口服葡萄糖耐量试验（OGTT）或日间曲线（DC）后 GH 的分泌模式与 IGF-I 的关系，并评估治疗对 OGTT 的影响。我们对 1988 年 1 月至 2005 年 12 月在我科进行的 93 例肢端肥大症患者的 279 次 OGTT 进行了回顾性分析，其中 77 例患者还获取了 DC 数据。GH 浓度通过 3 种不同的系统（RIA、IRMA 和化学发光测定法）进行评估，IGF-I 通过 2 种 RIA 进行评估。约 12%的 OGTT 样本与基线不符，而最低点与 120 分钟之间的差异较小（5%），除了一个值外，所有差异值都接近截止值。所有数值中，DC 和 OGTT 数据之间的相关性约为 0.99，最低点与最小 DC 之间的差异率远低于与平均 DC 的差异率。在近 80%的情况下，OGTT 和 DC 结果完全一致，约 30%的 IGF-I 与 GH 不符。IGF-I 与 GH 之间的相关性分析以 DC 数据最高，以 OGTT 基线（T0）最低。考虑到不同的治疗方法，GH 和 IGF-I 之间的差异率相当。最佳 GH 参数是最小 GH DC，尽管在临床实践中，OGTT GH 与 IGF-I 联合评估是最实用的方法。在这种情况下，基础和 T120 GH 值可以替代多次采样。不同的治疗方式并不影响 GH 和 IGF-I 之间的差异率。
