Department of Clinical Biochemistry, Amager and Hvidovre Hospital, Hvidovre, Denmark.
Department of Clinical Biochemistry, Bispebjerg and Frederiksberg Hospital, København, NV, Denmark.
Scand J Clin Lab Invest. 2024 Sep;84(5):305-310. doi: 10.1080/00365513.2024.2392116. Epub 2024 Aug 20.
This aim of this study was to assess the possible association between diurnal oscillations and biochemical markers associated with calcium homeostasis. This included the markers parathyroid hormone (PTH), total calcium, total alkaline phosphatase, phosphate, and 25-hydroxyvitamin D (25-OH-D). By examining the influence of circadian rhythms on these parameters, the study aimed to deepen the understanding of calcium metabolism dynamics and its clinical implications.
Blood samples from 24 Caucasian male volunteers aged 20 to 40 (mean age 26) with normal pulse, blood pressure, and BMI were analyzed for biochemical markers related to calcium homeostasis. Data was obtained from the Bispebjerg study of diurnal variations. Blood samples were collected every three hours over a 24-hour period. Patients were fasting from 22:00 to 09:00. The participants spent 24 h in the hospital ward, receiving regular meals and engaging in low-intensity activities. They experienced 15 h of daylight and 9 h of complete darkness during sleep. Diurnal oscillations were analyzed using cosinor analysis with statistical significance set at < 0.05.
Total calcium, phosphate, and PTH exhibited significant diurnal variations. Total calcium and PTH were inversely synchronized while PTH and phosphate oscillated in synchronization. The three parameters showed relatively large amplitude/reference range ratios from 25.4% to 41.5%.
This study found notable fluctuations in total calcium, phosphate, and PTH levels over a 24-hour cycle, while 25-OH-D and total alkaline phosphatase remained consistent. It highlights the importance of considering sampling times for total calcium, PTH, and phosphate in clinical settings.
本研究旨在评估昼夜节律波动与钙稳态相关生化标志物之间可能存在的关联。这些标志物包括甲状旁腺激素（PTH）、总钙、总碱性磷酸酶、磷酸盐和 25-羟维生素 D（25-OH-D）。通过研究昼夜节律对这些参数的影响，旨在加深对钙代谢动力学及其临床意义的理解。
对 24 名年龄在 20 岁至 40 岁（平均年龄 26 岁）的高加索男性志愿者的血液样本进行分析，以评估与钙稳态相关的生化标志物。这些数据来自比斯加夫研究昼夜节律变化获得。在 24 小时内，每 3 小时采集一次血液样本。患者从 22:00 到 09:00 禁食。参与者在医院病房中度过 24 小时，接受常规饮食并进行低强度活动。他们在睡眠期间经历了 15 小时的日光和 9 小时的完全黑暗。使用余弦分析对昼夜节律波动进行分析，统计显著性水平设为 < 0.05。
总钙、磷酸盐和 PTH 表现出明显的昼夜变化。总钙和 PTH 呈负同步变化，而 PTH 和磷酸盐呈同步振荡。这三个参数的相对振幅/参考范围比为 25.4%至 41.5%。
本研究发现，在 24 小时周期内，总钙、磷酸盐和 PTH 水平出现显著波动，而 25-OH-D 和总碱性磷酸酶保持稳定。这强调了在临床环境中考虑总钙、PTH 和磷酸盐采样时间的重要性。
