Figure 1
November 1, 2005
We have repeatedly stressed the important influence of posttransplant hypertension on longterm kidney graft outcome, both in the CTS newsletters (1:1998 and 3:2004) and a peerreviewed publication (Kidney Int 1998; 53:217-222). We can now report to you on the impressive fact that the median blood pressure 1 year posttransplant as reported to the CTS study, which did not change in 1985-1998, began to decline significantly in temporal association with those publications.
Figure 1
Figure 1 shows the striking change in the 1-year systolic blood pressure (SBP) among patients transplanted after our findings were published. A very similar change was found when SBP was examined 2 and 3 years posttransplant (not shown). The key question, of course, is whether improved management of hypertension results in better graft survival. We have analyzed the available data and found evidence supporting the hypothesis that lowering patient blood pressure is beneficial to outcome.
Figure 2
Figure 2 shows an analysis in which patients with SBP > 140 mm Hg at 1 and 3 years were compared to patients with 1-year SBP > 140 mm Hg but improvement at 3 years to = 140 mm Hg. Patients with this decrease in SBP at 3 years had a significantly better longterm outcome.
Figure 3
Figure 3 demonstrates that this phenomenon was observed even when patient death was censored, indicating that hypertension has a direct damaging effect on the kidney.
However, we did find that mortality due to cardiovascular cause was significantly lower in those patients whose blood pressure had decreased, albeit only among relatively young patients < 50 years of age at time of transplantation. Overall, patient survival improved significantly in recipients whose SBP was successfully lowered (Figure 4).
Figure 4
Additional investigation at 5 years revealed that lasting improvement was achieved only when systolic pressure after lowering to = 140 mm Hg at 3 years was maintained at this low level to 5 years.
Figure 5
Patients in whom the pressure was reduced only temporarily (> = >, n = 929) benefitted very little, whereas patients in whom systolic pressure was maintained at = 140 mm Hg to 5 years (> = =, n = 1759) benefitted greatly. Even control of hypertension at 5 years after 3 years of hypertension was associated with improved longterm outcome (> > =, n = 1230) (Figure 5).
The results were confirmed by a Cox regression analysis, which demonstrated that the beneficial effect of blood pressure lowering was not an indirect result of confounding factors. Altogether, the positive effect of improved blood pressure control, even following a period of posttransplant hypertension, is very encouraging.
Credit is due to all centers who provided the yearly information on posttransplant blood pressure on which the CTS analysis was based. This effort made this important contribution towards the better understanding of blood pressure control in transplant recipients possible. Certainly, the current data provide encouragement for rigorously monitoring and treating posttransplant hypertension.
The following centers contributed data for this analysis:
Aachen, Adelaide (Queen Elizabeth), Ankara (Baskent University), Antalya, Augsburg, Baracaldo, Barcelona (Belvitge), Barcelona (Vall d'Hebron), Bari, Barquisimeto, Basel, Belfast, Belo Horizonte (HC UFMG), Belo Horizonte (Biocor), Berlin (Benjamin Franklin), Bern, Bochum, Bremen, Budapest, Buenos-Aires (Italiano), Buenos-Aires (Instituto de Nefrologia), Buenos-Aires (Sanatorio Mitre), Cambridge, Cape Town (Tygerberg), Cape Town (Christiaan Barnard Memorial), Cape Town (Groote Schuur), Caracas, Cardiff, Christchurch, Cincinnati, Cleveland, Cologne-Merheim, Cologne-Lindenthal, Dallas (Methodist), Dallas (St. Paul), Debrecen, Duesseldorf, Edmonton, Erlangen-Nuernberg, Essen, Florence, Frankfurt, Freiburg, Fulda, Geneva, Genova (Gaslini), Giessen, Glasgow, Goettingen, Grand Rapids, Guadalajara (Civil), Guadalajara (Mexico Americano), Halle, Hamilton, Hann-Muenden, Heidelberg (AUS), Heidelberg (GER), Homburg, Hong Kong (Caritas), Hong Kong (Kwong Wah), Hong Kong (Prince of Wales), Hong Kong (Princess Margaret), Hong Kong (Queen Elizabeth), Hong Kong (Queen Mary), Hong Kong (Tuen Mun), Istanbul, Izmir (Dokuz Eylul University), Izmir (SSK Tepecik), Jena, Kaiserslautern, Katowice, Kaunas, Kiel, Lausanne, Leicester, Leuven, Liege, Lille, Lima, Linz, Ljubljana, London (Royal), Louisville, Luebeck, Lyon, Maceio, Madrid (Fundacion Jimenez Diaz), Mainz, Manila (National Kidney and Transplant Institute), Manila (St. Luke's Medical Center), Mannheim, Mar del Plata, Maracaibo, Marburg, Mashad, Medellin, Melbourne (St. Vincent), Mexico City, Milan (Maggiore Policlinico), Milan (Niguarda), Milan (S. Raffaele), Muenster, Nancy, Nantes, New Delhi, New Orleans, Newcastle, Nijmegen, Nottingham, Omaha, Orlando, Oviedo, Padua, Pamplona, Pato Branco, Pavia, Pecs, Perth, Poitiers, Porto Alegre (Centro de Dialise e Transplante), Prague, Quebec, Regensburg, Reims, Rio de Janeiro, Rosario, Rostock, Santa Fe, Santander, Santiago (San Juan de Dios), Santiago (Pontificia Universidad), Sao Paulo (Beneficencia Portuguesa), Sao Paulo (Dom Silvero), Sao Paulo (Hospital Sao Paulo), Seoul, Shreveport, St. Gallen, Strasbourg, Stuttgart, Sydney (Concord), Sydney (Royal North Shore), Sydney (St. Vincent), Sydney (Westmead), Sydney (Royal Prince Alfred), Szeged, Tehran, Tel Aviv, Toulouse, Treviso, Tuebingen, Turin (S. Giovanni), Turin/Novara, Ulm, Uppsala, Urmia, Valdivia, Valencia (Dr Peset), Valencia (La Fe), Valhalla, Vicenza, Vilnius, Winnipeg, Wuerzburg, Zagreb, Zurich.
Please remember that the next deadline for shipping material for the CTS serum and DNA typing studies is
November 21/22, 2005.
Please inform us about shipping details (e-mail, fax, or telephone) so that we can follow up on shipments from our end.
The serum study shows impressive preliminary results. We would like to ask all participants to provide a current serum sample on all patients who are already enrolled in the study. Furthermore, even those centers who have not yet contributed are encouraged to enroll new patients. Details on enrollment and serum requests can be found on the CTS website (www.ctstransplant.org) under "Methodology", "Special Studies".
Thank you very much for your continued generous support of these important studies.
I would like to thank all the colleagues who have purchased CTS reagents over the years. The small profit derived by our laboratory from manufacturing these low-cost reagents is crucial to us for continuing this international study. The reagents are now officially CE-certified. If you have not thought about it, please consider contributing to the study by ordering CTS reagents. All profit from the sale of these reagents is used exclusively for study purposes.
We appreciate your continued suggestions for CTS website improvements, several of which were implemented during this past year. The fact that our site receives well over 200 visits from users per day substantiates the success of the CTS website endeavor. Nevertheless, improvements can always be made, so please do not hesitate to contact us if you have any suggestions for further changes.
During conversations at the ESOT congress in Geneva I noticed an apparent misunderstanding concerning the EBV questionnaires that were distributed recently. Even if only the recipient EBV status is known, the information will be very useful for epidemiological studies. Please provide the recipient information even if you do not have access to information on donor EBV. Your contribution will be highly appreciated.
Thank you for your continued support of the international collaborative transplant study.
Sincerely yours,