ACE genotype, body weight changes and target organ damage in renal transplant recipients

Background: Carriage of the angiotensin-converting enzyme (ACE) D-allele favors weight gain in mid-life and, possibly, cardiovascular complications; we aimed to verify the relationship between these conditions and ACE polymorphisms in the renal transplant (RTx) setting. Methods: ACE genotypes were evaluated in 169 RTx recipients (107 males, 62 females) and related to body mass index (BMI; kg/m²) changes 1 year after transplant, as well as to cardiovascular events and allograft loss. Allelic frequencies and body weights were compared with those of a control group (age- and sex-matched healthy blood donors). Results: Allelic frequencies were 0.639 and 0.669 for the D-allele, and 0.361 and 0.331 for the I-allele, in recipients and controls, respectively (p=NS). In the patient population, carriage of the I/* allele was associated with a BMI >23 at the time of RTx (p<0.005). In contrast, in the control group, higher BMI values tended to occur in D/* carriers. Moreover, BMI values were higher in the control group (24.7 ± 3.5 vs. 23.6 ± 3.3, p=0.003) but, 1 year after RTx, this difference was nullified. At multivariate analysis, the factors associated with weight gain after RTx were ACE D/D (odds ratio [OR] = 2.35, 95% confidence interval [95% CI], 1.00-5.49) and age at RTx ≤49 years (OR=2.82, 95% CI, 1.30-6.13); the factors associated with cardiovascular events and/or allograft loss were cyclosporine-based immunosuppressive regimen (p=0.002), history of smoking (p=0.005) and dyslipidemia (p<0.05). Conclusion: Body weight at the time of RTx and weight gain 1 year after RTx, but not cardiovascular complications and allograft loss, are related to the ACE I/D genotype of RTx recipients.