( CNN ) -- Carmichael Griffin did n't think anything of it when his face began to swell . He assumed he had just gained a couple of pounds . But when the swelling progressed to severe vomiting and frequent urination , he knew something was wrong . It turned out that both of his kidneys were failing . He was suffering from hypertension , a common ailment among African-American patients . `` My blood pressure had scarred my kidneys so much they were surprised I did n't have a stroke then , '' said Griffin , 32 . `` I was a walking time bomb . '' That was nearly 12 years ago . The Washington-based music producer and actor has been on dialysis and awaiting a kidney transplant since then . A study published this month by the American Journal of Kidney Diseases shows that African-American patients awaiting a new organ are less likely to get one than non-black patients . At the 275 transplant centers in the United States , African-Americans had at least a 35 % lower chance of receiving a live kidney donation , said Dr. Erin Hall of the Department of Surgery at the Johns Hopkins University School of Medicine . At some centers , African-Americans had a 76 % lower chance of getting an organ . The study surveyed 247,707 adults registered for first-time kidney transplants from 1995 to 2007 . About 92,000 people in the United States are on a waiting list for a kidney transplant . More than one-third are African-Americans , according to the National Kidney Foundation . In 2011 , 5,771 living donor transplants were performed , 813 on African-American patients . `` African-Americans had lower odds of obtaining living donor kidney transplantation at every transplant center in the country , '' Hall said . Living donor transplants -- donations of an organ or part of an organ from a live person -- are the best option . A kidney from a living donor usually starts to function immediately . In some cases , a kidney from a deceased donor may require a patient to remain on dialysis until it begins to function . The racial disparity may be attributed to education levels , economic factors or medical characteristics such as blood type , Hall said . Also , some centers may be more focused on deceased kidney transplants , she said . `` There 's also a higher prevalence of obesity and diabetes [ among African-Americans ] that would preclude you to become a donor , '' Hall said . Griffin believes there 's a lack of support and knowledge about kidney donation among African-Americans . He has asked family and friends for help , but to no avail . `` I am exhausted , '' he said . `` I have a couple of white friends who received transplants and a few black friends whose families donated it to them . Makes me wonder what I 'm doing wrong . '' He says more education is needed , that potential donors need to know that it 's not a life sentence for them . `` Of course living donor kidney transplantation involves not only the recipient of the kidney , but also the donor , '' Hall said . `` It could be the social networks of African-American populations . '' Hall advises frustrated African-American patients that it is never too late to take control of their medical care , and to continue to ask . She suggests patients educate themselves more on the process of living organ donation so that they become more comfortable speaking with potential donors . `` If we continue to fight for them , and they continue to fight for themselves , we can reach a good solution , '' Hall said . Griffin has stopped asking family and friends for an organ , but he continues to produce music and act . His hope is that he can one day do those things away from a dialysis machine .
Thousands of patients in the U.S. are in need of a kidney transplant . Study : African-Americans have lower odds of getting a live donor . Comment: