Gann P H, Giovanazzi S, Van Horn L, Branning A, Chatterton R T
Department of Preventive Medicine, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Medical School, Chicago, Illinois 60611, USA.
Cancer Epidemiol Biomarkers Prev. 2001 Jan;10(1):59-64.
Repeated measurement of ovarian steroids in saliva could provide an advantage in studies estimating long-term sex steroid exposure in premenopausal women, by reducing the measurement error associated with collection of serum or urine samples. We previously reported on characteristics of ultrasensitive RIAs adapted for extraction-free measurement of estradiol (E2) and progesterone (PG) in saliva. The purpose of the present study was to evaluate the consistency of E2 and PG levels in saliva in the same women across menstrual cycles, and to compare this with the variation observed between women. We also evaluated the effect of altering the number of consecutive daily samples considered and the method for locating a particular cycle day in relation to ovulation (day 0). Study participants included 12 healthy women who provided daily saliva samples for two consecutive, ovulatory menstrual cycles. A single midluteal serum sample was collected 7-8 days after detection of a luteinizing hormone (LH) peak in urine. We plotted individual cycle profiles and computed intraclass correlation coefficients (ICC) for various definitions of peak and cumulative daily hormone level. For peak PG, determined as the maximal running 3-day mean, ICC was 0.68. For cumulative PG, based on 8 consecutive cycle days (+2 to +9), ICCs were 0.72-0.76 when reverse dating LH peak or rise in salivary PG determined day 0. For E2, ICCs ranged from 0.74 to 0.79 by various dating methods for the 5 preovulatory days (-4-0), and from 0.85 to 0.92 for the 15 days about the center of the cycle (-6 to +8). With exclusion of just the first 5 days of the cycle, the ICC for E2 was 0.91. For both E2 and PG, selection of 5 or 7 days for the estimation of the midluteal mean level provided separation of within and between subject variance that was comparable with a LH-timed serum sample. These results indicate that daily saliva samples can be combined to clarify the interindividual differences in E2 and PG levels in premenopausal women, and that these interindividual differences may be greater than previously imagined.
唾液中卵巢甾体激素的重复测量，通过减少与血清或尿液样本采集相关的测量误差，在评估绝经前女性长期甾体激素暴露的研究中可能具有优势。我们之前报道了适用于唾液中雌二醇（E2）和孕酮（PG）免提取测量的超灵敏放射免疫分析的特性。本研究的目的是评估同一女性在月经周期中唾液中E2和PG水平的一致性，并将其与女性之间观察到的变异进行比较。我们还评估了改变连续每日样本数量以及确定相对于排卵（第0天）的特定周期日的方法的影响。研究参与者包括12名健康女性，她们连续两个有排卵的月经周期每天提供唾液样本。在检测到尿中促黄体生成素（LH）峰值后7 - 8天采集一份黄体中期血清样本。我们绘制了个体周期曲线，并计算了各种峰值和累积每日激素水平定义的组内相关系数（ICC）。对于确定为最大连续3天平均值的峰值PG，ICC为0.68。对于基于连续8个周期日（+2至+9）的累积PG，当以LH峰值反向推算或唾液PG升高确定第0天时，ICC为0.72 - 0.76。对于E2，在排卵前5天（-4至0）通过各种推算方法，ICC范围为0.74至0.79，在周期中心约15天（-6至+8）为0.85至0.92。仅排除周期的前5天，E2的ICC为0.91。对于E2和PG，选择5天或7天来估计黄体中期平均水平，提供了与LH定时血清样本相当的个体内和个体间方差分离。这些结果表明，每日唾液样本可以合并以阐明绝经前女性E2和PG水平的个体间差异，并且这些个体间差异可能比之前想象的更大。
