Date Published: September 6, 2011
Publisher: Hindawi Publishing Corporation
Author(s): Jonathan Heldt, Robert Torrey, Daniel Han, Pedro Baron, Christopher Tenggardjaja, Justin McLarty, Tekisha Lindler, D. Duane Baldwin.
Background. While tobacco use by a renal transplant recipient has been shown to negatively affect graft and patient survival, the effect of smoking on the part of the kidney donor remains unknown. Methods. 29 smoking donors (SD) and their recipients (SD-R) as well as 71 non-smoking donors (ND) and their recipients (ND-R) were retrospectively reviewed. Preoperative demographics and perioperative variables including serum creatinine (Cr) and glomerular filtration rate (GFR) were calculated and stratified by amount of tobacco exposure in pack-years. Clinical outcomes were analyzed with a Student’s t-test, chi-square, and multiple linear regression analysis (α = 0.05). Results. At most recent followup, SD-R’s had a significantly smaller percent decrease in postoperative Cr than ND-R’s (−57% versus −81%; P = 0.015)
and lower calculated GFR’s (37.0 versus 53.0 mL/min per 1.73 m2; P < 0.001). SD's had a larger percent increase in Cr than ND's at most recent followup (57% versus 40%; P < 0.001), with active smokers having a larger increase than those who quit, although this difference was not statistically significant (68% versus 52%; P = 0.055). Conclusions. Use of tobacco by kidney donors is associated with decreased posttransplant renal function, although smoking cessation can improve outcomes. Kidneys from donors who smoke should be used with caution.
Cigarette smoking is the leading preventable cause of death in the United States and is thought to be responsible for about one in five deaths annually, or approximately 438,000 deaths per year . The effects of tobacco use on the body are widespread, affecting primarily the cardiovascular  and pulmonary [3, 4] systems while exerting carcinogenic effects in multiple organ systems [5–8]. As with other organs, the kidney is susceptible to the pathogenic effects of tobacco use . During the last decade, a body of research has accumulated demonstrating the deleterious effects of recipient tobacco consumption upon graft function and patient outcomes [10–15]. However, the effect of cigarette smoking by the kidney donor has not previously been reported. The purpose of this study is to retrospectively compare renal function in donors with a history of tobacco use against donors who have never smoked as well as to evaluate their respective recipients’ renal function and graft outcomes.
A retrospective chart and database review was performed on 100 hand-assisted laparoscopic donors and their 100 recipients at a single university hospital from February 2003 through June 2005, with 29 smoking donors (SD) and their recipients (SD-R) as well as 71 non-smoking donors (ND) and their recipients (ND-R). Demographic data including age, body mass index (BMI), sex, and ethnicity were obtained and evaluated for all patients. Donor creatinine (Cr) levels were evaluated at 1 week, 3 months, and 6 months while recipient Cr levels were evaluated at 1 month, 6 months, and at 6 month intervals thereafter. In addition, levels of the immunosuppressive drugs cyclosporine A and tacrolimus were also compared in recipients at 1 week, 3 months, and 6 months.
There were no statistically significant differences between the groups with respect to age, BMI, sex, or presence of significant comorbidities such as hypertension and diabetes (Table 1). No patients in either donor group had hypertension requiring medication or hospitalization, as this comorbid condition would preclude kidney donation at our institution. Ethnicity in the donor group was also evaluated, but due to a prevalence of Hispanic (43%) and Caucasian (46%) patients, the relative effects of African-American (7%) and Asian (2%) race could not be accurately assessed. Thirteen patients in the SD group (45%) were actively smoking at the time of surgery while the remaining 16 had a past history of previous tobacco use but had quit smoking by the time of donation.
Tobacco use has been demonstrated to have pathologic effects on the kidney. Patients who smoke experience increased sympathetic nervous activity, leading to hypertension, hyperfiltration, albuminuria, and proximal tubular function damage, while also having a higher prevalence of chronic renal disease [9, 17]. Patients exposed to tobacco also have considerable changes in endothelial cell ultrastructure which increase the risk of atherosclerosis, hyperactive platelets which increase the chance of thrombogenesis, and an altered immune system leading to immune-mediated renal diseases [9, 17].
Donors who actively smoke or have a past history of tobacco use have a larger percent increase in Cr at one year following donation compared to donors who have never smoked. Recipients of kidneys from SDs showed significantly less improvement in long-term postoperative Cr and lower GFR’s when compared to recipients of ND kidneys. While smoking cessation by the donors can be protective, kidneys from donors with no history of smoking provide the best outcomes. Donors with prior tobacco exposure should be used with caution due to the negative impact upon both donor and recipient renal function.