Herblum Jordana, Dacouris Niki, Huang Michael, Zaltzman Jeffrey, Prasad G V Ramesh, Nash Michelle, Chen Lucy
Keenan Research Summer Student Program, St. Michael's Hospital, Toronto, ON, Canada.
Kidney and Metabolism Program, Unity Health Toronto, ON, Canada.
Can J Kidney Health Dis. 2021 Jun 15;8:20543581211021742. doi: 10.1177/20543581211021742. eCollection 2021.
Increased intrapatient variability (IPV) in tacrolimus levels is associated with graft rejection, de novo donor-specific antibodies, and graft loss. Medication nonadherence may be a significant contributor to high IPV.
The objective of this study is to determine the utility of tacrolimus IPV in detecting nonadherence by examining the relationship between self-reported adherence and tacrolimus coefficient of variability (COV), a measure of IPV.
Retrospective cohort study.
St. Michael's Hospital, Toronto, Ontario.
All patients who were at least 1-year post-kidney transplant as of March 31, 2019, prescribed tacrolimus as an immunosuppressant and had a self-reported adherence status. Patients were excluded from the primary analysis of examining the correlation between COV and self-reported adherence if they lacked a calculatable COV.
Self-reported adherence, COV, demographic data, transplant, and medication history.
A modified Basel Assessment of Adherence to Immunosuppressive Medications Scale (BAASIS) administered by healthcare professionals to assess self-reported adherence was used. The COV of tacrolimus trough levels was calculated and its correlation to BAASIS response was noted. The median COV was used as a cutoff to examine the characteristics of patients deemed "high COV" and "low COV."
A total of 591 patients fit the initial criteria; however, only 525 had a recent calculatable COV. Overall, 92.38% of the population were adherent by self-report. Primary analysis identified a COV of 25.2% and 29.6% in self-reported adherent and nonadherent patients, respectively, though the result was not significant ( = .2). Secondary analyses showed a significant correlation between younger age at transplant and at the time of adherence self-reporting with nonadherence ( = .01). In addition, there was a strong correlation between those nonadherent with routine post-transplant blood work and younger age ( < .01).
The limitations included modified nonvalidated BAASIS questionnaire, social desirability bias, BAASIS only administered in English, and patients with graft failure not active in clinic not being captured.
The COV should not be used as the sole method for determining medication adherence. However, COV may have some utility in capturing individuals who are not adherent to their blood work or patients who are having a poor response to tacrolimus and should be switched to another medication.
他克莫司血药浓度的患者内变异性（IPV）增加与移植排斥反应、新生供者特异性抗体及移植肾丢失相关。药物治疗依从性差可能是导致高IPV的一个重要因素。
本研究的目的是通过检查自我报告的依从性与他克莫司变异系数（COV，一种IPV测量指标）之间的关系，确定他克莫司IPV在检测依从性方面的效用。
回顾性队列研究。
安大略省多伦多市圣迈克尔医院。
截至2019年3月31日肾移植术后至少1年、服用他克莫司作为免疫抑制剂且有自我报告依从性状态的所有患者。如果患者缺乏可计算的COV，则排除在检查COV与自我报告依从性之间相关性的主要分析之外。
自我报告的依从性、COV、人口统计学数据、移植及用药史。
使用由医疗保健专业人员管理的改良版免疫抑制药物治疗依从性巴塞尔评估量表（BAASIS）来评估自我报告的依从性。计算他克莫司谷浓度的COV，并记录其与BAASIS反应的相关性。将COV的中位数用作临界值，以检查被视为“高COV”和“低COV”的患者特征。
共有591名患者符合初始标准；然而，只有525名患者近期有可计算的COV。总体而言，92.38%的患者自我报告为依从。主要分析发现，自我报告依从和不依从的患者中COV分别为25.2%和29.6%，尽管结果无统计学意义（P = 0.2）。二次分析显示，移植时及自我报告依从性时年龄较小与不依从之间存在显著相关性（P = 0.01）。此外，未按常规进行移植后血液检查的患者与年龄较小之间存在强相关性（P < 0.01）。
局限性包括改良的未经验证的BAASIS问卷、社会期望偏差、BAASIS仅以英语进行、未纳入移植肾失功且未在门诊就诊的患者。
COV不应作为确定药物治疗依从性的唯一方法。然而，COV在识别未按要求进行血液检查的个体或对他克莫司反应不佳且应换用其他药物的患者方面可能有一定作用。
