Katz Marcelo E, Margulis Fernando, Schiavelli Rubén, Arias Pablo, Head Geoffrey A, Golombek Diego A
Department of Science and Technology, University of Quilmes Buenos Aires, Argentina.
Front Neurol. 2012 Mar 16;3:35. doi: 10.3389/fneur.2012.00035. eCollection 2012.
Patients with kidney replacement exhibit disrupted circadian rhythms. Most studies measuring blood pressure use the dipper/non-dipper classification, which does not consider analysis of transitional stages between low and high blood pressure, confidence intervals nor shifts in the time of peak, while assuming subjective onsets of night and day phases. In order to better understand the nature of daily variation of blood pressure in these patients, we analyzed 24 h recordings from 41 renal transplant recipients using the non-symmetrical double-logistic fitting assessment which does not assume abruptness nor symmetry in ascending and descending stages of the blood pressure profile, and a cosine best-fitting regression method (Cosinor). Compared with matched controls, double-logistic fitting showed that the times for most transitional stages (ascending systolic and descending systolic, diastolic, and mean arterial pressure) had a wider distribution along the 24-h. The proportion of individuals without daily blood pressure rhythm in the transplanted group was larger only for systolic arterial pressure, and the amplitude showed no significant difference. Furthermore, the transplant recipient group had a less pronounced slope in descending systolic and ascending mean blood pressure. Cosinor analysis confirmed this phase-related changes, showing a wider distribution of times of peak (acrophases). We conclude that daily disruptions in renal transplant recipients can be explained not necessarily by an absence in diurnal variation, but also by changes in waveform-related parameters of the rhythm, and that alterations in the phase of the rhythm are the most consistent finding in these patients.
接受肾脏替代治疗的患者表现出昼夜节律紊乱。大多数测量血压的研究采用勺型/非勺型分类法，该方法未考虑对血压高低转换阶段的分析、置信区间以及峰值时间的偏移，同时假设昼夜阶段的起始是主观的。为了更好地了解这些患者血压每日变化的本质，我们使用非对称双逻辑拟合评估和余弦最佳拟合回归方法（Cosinor），对41名肾移植受者的24小时记录进行了分析。非对称双逻辑拟合评估不假定血压曲线上升和下降阶段的突然性或对称性。与匹配的对照组相比，双逻辑拟合显示，大多数转换阶段（收缩压上升和下降、舒张压和平均动脉压）的时间在24小时内分布更广泛。移植组中无每日血压节律的个体比例仅在收缩压方面较大，且幅度无显著差异。此外，移植受者组在收缩压下降和平均血压上升方面的斜率较小。Cosinor分析证实了这种与阶段相关的变化，显示峰值时间（峰相位）分布更广泛。我们得出结论，肾移植受者的每日节律紊乱不一定可以通过昼夜变化的缺失来解释，也可以通过节律与波形相关参数的变化来解释，并且节律相位的改变是这些患者中最一致的发现。
