We read with great interest the article by Wyld et al1 addressing circulatory death rates in kidney transplant recipients in New Zealand and Australia and applaud their effort to put focus on the number 1 disease leading to premature death in this population. The report is impressive with data on 16 329 kidney transplant recipients collected from 1988 until December 31, 2013, and includes an analysis of 5089 postengraftment deaths where they find 918 (18%) to be cardiac. It is reassuring to see that cardiovascular (CV) disease has been reduced by >40% during the period they cover, but it is depressing to see that CV risk remains dramatically elevated. The authors find that the risk of circulatory death was associated with older age, male sex, longer dialysis duration, previous graft failure, known coronary disease, and kidney failure due to diabetes or hypertension. We also read the nice commentary by Reed & Locke addressing the important opportunities for improvement in posttransplant care of all patients but particularly among women to reduce the gender disparities in transplant outcomes.2 We agree!
Unfortunately, the Australia and New Zealand registry data lack information on posttransplant hypertension (eg, whether blood-pressure [BP] targets were met), which is only briefly mentioned in the discussion section as a limiting factor. Posttransplant hypertension is a well-recognized risk factor for CV disease and contrary to age, sex, time in dialyses, and so on, a risk factor that can, and should be, treated. Previously, focus has been put on this risk factor among others quite elegantly by Opelz et al3 and as a “spin-off” of the Folic Acid for Vascular Outcomes Reduction in Transplantation trial.4 This knowledge is, however, often neglected, and it does not help much with Kidney Disease: Improving Global Outcomes guidelines as long as nephrologists repetitively remain more interested in individualizing calcineurin inhibitor concentration and graft function than focusing on the possibility of improved treatment of hypertension and thereby reduce CV morbidity and mortality. In publications focusing on BP treatment in a kidney transplant population, it is common to acknowledge that approximately 40%–50% do not reach the warranted target. Reasons for this can vary but nonadherence to prescribed antihypertensive medication is often mentioned. Due to different healthcare systems, lack of access may also be a contributing factor. We recently performed a nationwide registry study addressing BP treatment in renal transplant recipients.5 Annual forms were received from 98% (3407/3486) of the Norwegian kidney transplant recipients, with 52% reporting a BP > 130/80 mm Hg. As in the article by Wyld et al,1 the hypertensive recipients were found to be older, mostly male, with higher body mass index and plasma creatinine compared with the recipients reaching a BP < 130/80 mm Hg. To our surprise, 9% of the hypertensive recipients were not on any antihypertensive treatment! Only 7% reported unwanted side effects as a dose-limiting factor. We conclude that current BP control in kidney transplant recipients is suboptimal, with the potential for improved target achievement at a level of 75%–80%. This treatment is relatively cheap, easy to monitor, and will most likely also have a major impact on reducing CV mortality and morbidity in kidney transplant recipients. So, let us not forget, posttransplant hypertension matters!
1. Wyld MLR, De La Mata NL, Masson P, et al. Cardiac mortality in kidney transplant patients: a population-based cohort study 1988–2013 in Australia and New Zealand. Transplantation. 2021;105:413–422.
2. Reed RD, Locke JE. Cardiac mortality following kidney transplantation: progress made but still room for improvement. Transplantation. 2021;105:278–279.
3. Opelz G, Döhler B; Collaborative Transplant Study. Improved long-term outcomes after renal transplantation associated with blood pressure control. Am J Transplant. 2005;5:2725–2731.
4. Carpenter MA, John A, Weir MR, et al. BP, cardiovascular disease, and death in the folic acid for vascular outcome reduction in transplantation trial. J Am Soc Nephrol. 2014;25:1554–1562.
5. Onsøien MO, Midtvedt K, Reisæter AV, et al. Blood pressure treatment in kidney transplant recipients-can we improve? Transplant Direct. 2021;7:e688.