Endocrinology Unit, Department of Internal Medicine and Center of Excellence for Biomedical Research, University of Genoa, Genoa, Italy.
Endocrinology Unit, IRCCS Ospedale Policlinico San Martino, Genoa, Italy.
J Clin Endocrinol Metab. 2021 Mar 8;106(3):789-801. doi: 10.1210/clinem/dgaa859.
Discordant growth hormone (GH) and insulin-like growth factor-1 (IGF-1) values are frequent in acromegaly.
To evaluate the impact of different GH cutoffs on discordance rate. To investigate whether the mean of consecutive GH measurements impacts discordance rate when matched to the last available IGF-1 value.
Retrospective study.
Referral center for pituitary diseases.
Ninety acromegaly patients with at least 3 consecutive evaluations for GH and IGF-1 using the same assay in the same laboratory (median follow-up 13 years).
Multimodal treatment of acromegaly.
Single fasting GH (GHf) and IGF-1 (IGF-1f). Mean of 3 GH measurements (GHm), collected during consecutive routine patients' evaluations.
At last evaluation GHf values were 1.99 ± 2.79 µg/L and age-adjusted IGF-1f was 0.86 ± 0.44 × upper limit of normality (mean ± SD). The discordance rate using GHf was 52.2% (cutoff 1 µg/L) and 35.6% (cutoff 2.5 µg/L) (P = 0.025). "High GH" discordance was more common for GHf <1.0 µg/L, while "high IGF-1" was predominant for GHf <2.5 µg/L (P < 0.0001). Using GHm mitigated the impact of GH cutoffs on discordance (GHm <1.0 µg/L: 43.3%; GHm <2.5 µg/L: 38.9%; P = 0.265). At receiver-operator characteristic curve (ROC) analysis, both GHf and GHm were poor predictors of IGF-1f normalization (area under the curve [AUC] = 0.611 and AUC = 0.645, respectively). The prevalence of disease-related comorbidities did not significantly differ between controlled, discordant, and active disease patients.
GH/IGF-1 discordance strongly depends on GH cutoffs. The use of GHm lessen the impact of GH cutoffs. Measurement of fasting GH levels (both GHf and GHm) is a poor predictor of IGF-1f normalization in our cohort.
肢端肥大症患者常出现生长激素（GH）和胰岛素样生长因子-1（IGF-1）值不一致的情况。
评估不同 GH 截断值对不一致率的影响。研究当与最后一次可用的 IGF-1 值匹配时，连续 GH 测量的平均值是否会影响不一致率。
回顾性研究。
垂体疾病转诊中心。
90 例肢端肥大症患者，至少有 3 次使用同一实验室相同检测方法进行的 GH 和 IGF-1 连续评估（中位随访 13 年）。
肢端肥大症的多模式治疗。
单次空腹 GH（GHf）和 IGF-1（IGF-1f）。在连续常规患者评估期间收集的 3 次 GH 测量值的平均值（GHm）。
在最后一次评估时，GHf 值为 1.99 ± 2.79 µg/L，年龄校正后的 IGF-1f 为 0.86 ± 0.44 × 正常值上限（平均值 ± SD）。使用 GHf 的不一致率为 52.2%（截断值 1 µg/L）和 35.6%（截断值 2.5 µg/L）（P = 0.025）。GHf <1.0 µg/L 时“高 GH”不一致更为常见，而 GHf <2.5 µg/L 时“高 IGF-1”更为常见（P < 0.0001）。使用 GHm 减轻了 GH 截断值对不一致性的影响（GHm <1.0 µg/L：43.3%；GHm <2.5 µg/L：38.9%；P = 0.265）。在受试者工作特征曲线（ROC）分析中，GHf 和 GHm 对 IGF-1f 正常化的预测均较差（曲线下面积 [AUC] = 0.611 和 AUC = 0.645）。控制、不一致和活动疾病患者的疾病相关合并症患病率无显著差异。
GH/IGF-1 不一致性强烈依赖于 GH 截断值。使用 GHm 可减轻 GH 截断值的影响。在我们的队列中，空腹 GH 水平（GHf 和 GHm）的测量均是 IGF-1f 正常化的预测指标较差。
