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    Kidney Program Implements New Weight Policy for Transplant:
    Body Mass Index (BMI) Research Links Transplant Success to Weight

    by Steven Katznelson, M.D., Medical Director, Kidney Transplant Program, and Laura Miyashita

    During a kidney transplant evaluation doctors review an individual’s health to help predict his or her anticipated success with kidney transplant surgery. Specifically, doctors are looking for medical issues that may cause severe problems after transplant, including:

    • Presence of vascular disease

    • Ongoing infection

    • Recent malignancy (cancer)

    • Obesity
    “As researchers study these medical issues we continue to learn more about their impact on kidney transplantation,” says Steven Katznelson, M.D., medical director of California Pacific’s Kidney Transplant Program.

    Obesity’s Impact

    Recent published data describes the impact of obesity on successful kidney transplantation. Obesity, measured using body mass index or BMI (see BMI calculator at can lead to poor kidney transplant outcomes.

    Patients with a BMI greater than 35 at the time of transplant have up to a 40% increased loss of a kidney transplant and approximately a 30% increased risk of death after kidney transplant compared to patients with a lower BMI. Additionally, individuals who carry a lot of extra weight in the lower abdomen are at risk of having surgical wounds that heal poorly or become severely infected.

    California Pacific’s new BMI policy limits transplants to individuals with a BMI less than 35 to avoid unfavorable outcomes shown in recent data.

    New BMI Policy for Kidney Transplant Surgery

    After reviewing recent data surrounding obesity and transplant, California Pacific’s Kidney Team has developed a new policy regarding BMI cutoffs for its transplant candidates.“We will only transplant individuals with a BMI less than 35 to avoid outcomes such as kidney loss, severe wound infections, and an increased risk of death,” says Katznelson.

    California Pacific’s Kidney Team will, however, evaluate individuals with any level of BMI. “If patients come to us with a BMI over 40, we will set weight loss guidelines to get their BMI down to 40. At a BMI of 40, we will list patients for transplant but will set goals for weight loss down to a BMI of 35—the ‘transplant BMI’,” explains Katznelson. “If patients are unable to meet these goals they will be taken off of the wait list.”

    Sometimes individuals have an elevated BMI because of large muscle mass rather than excess fat (adipose). Because of this variation, the Kidney Team consider each individual on a case-by-case basis.

    article from Spring Summer 2011Kidney Review newsletter