Introduction:

Weight gain after kidney transplant has been documented, among other factors, due to reduced physical activity in the early months, increased appetite, and the use of immunosuppressants and corticosteroids.

Objetives:

To understand post-transplant weight gain. Indeed, to determine the relationship between weight gain and comorbidities, as well as, to evaluate changes in body composition.

Material and Method:

Prospective study, September 2020 to April 2023. Weight measurements were taken at 0, 3, 6, and 12 months.

Results:

Ninety-two patients were analyzed, 68.5% male, with an average age of 58±18.5 years. Pre-transplant weight was 72.5 (±5.8) kg, and at 12 months, it was 75.10 (±15.7) kg. Differences were found between first-time and repeat transplants (p=0.020). In the analysis of repeated measures of weight (p=0.022), differences were observed between month 0 and the third month, month 0 and one year, and between the third month and one year.

In muscle mass (p<0.001), differences were seen when comparing month 0 with the third, sixth, and twelfth months. Fat mass differed when comparing the third month with the twelfth month, and visceral fat (p=0.032) differed when comparing the third month with the sixth and twelfth months.

Conclusion:

After a kidney transplant, weight gain occurs, especially after the sixth month, reaching 5% per year. Muscle mass increases more than fat mass. People who received kidneys from living donors, those with previous transplants, and those with hypertension and/or cardiovascular disease experience greater weight gain.