Introduction: Osteonecrosis (ON) is a disabling disease, which often affects young adults after corticosteroid immunosuppression for organ transplantation. Reducing risk factors remains the only preventive measure for this condition. Our goal was to determine if diabetes has any influence in developing ON after kidney transplantation.

Materials and Methods: We identified 2881 renal transplantation patients with the following inclusion criteria: age > 16 years, no history of corticosteroid exposure. There were 1762 (61%) diabetics and 1119 (39%) non-diabetics. Mean age was 43 years (range, 16 to 77) and mean follow-up was 128 months (range, 36 to 242). Osteonecrosis free survivorship was defined as time from transplant to diagnosis of ON.

Results: Kaplan-Meier life table analysis at 5 years revealed that the incidence of ON was 4% for diabetics vs. 9% for non-diabetics (ON- free survivorship 96%, [95% confidence interval 0.952 to 0.970] vs. 91% [95% C.I. 0.896 to 0.929], respectively [p < 0.0001]). At 10 years, the ON incidence was 5% for diabetics vs. 10% for non-diabetics representing a 50% reduction.

Diabetes was the strongest independently predictive factor for ON-free survival (relative risk 0.47, p< 0.0001), while other factors were also independently significant but had a weaker relationship; (rejection episodes [RR 1.17, p=0.009], year of transplantation [RR 0.96, p=0.01]).

Discussion: Although the most common reason for renal transplantation, in adults, is diabetic nephropathy (61%), only a small fraction actually developed ON as compared to the non-diabetic population. The reason for this is unknown but might be related to lipid metabolism, high glucose levels, or neovascularization analogous to diabetic retinopathy.

Presence of diabetes is associated with a dramatic risk reduction in developing ON. The magnitude of the risk reduction was greatest for diabetes as compared to all other risk factors analyzed.

Introduction: The relationship between corticosteroids and osteonecrosis (ON) is well known. Limited data have suggested that statins modulate cholesterol metabolism and may protect against ON. We analyzed our, NIH supported, prospective renal transplant database to determine if statin usage reduces the incidence of corticosteroid-related osteonecrosis.

Materials and Methods: We identified 2881 renal transplantation patients who met our inclusion/exclusion criteria. There were 1752 male and 1129 female patients with mean age 43 years (range, 16 to 77). Mean follow-up was 128 months (range, 36 to 242 months). We identified 338 of 2881 patients as being on statins for over 1 year, commencing within 31 days of their transplant.

Results: Among the 338 patients on statins, 15 (4.4%) developed osteonecrosis vs. 180 of 2543 (7%) not on statins. Kaplan-Meier life table analysis of ON-free survival did not show a statistically significant relationship between statin exposure and development of ON (p=0.14, Log-Rank).

Discussion: We conclude that among our renal transplant patients, an association between statin usage and lower risk of osteonecrosis was not found, and if a reduction in incidence of ON actually exists, it is likely to be quite small. In addition, male gender and higher number of rejection episodes were independent predictive factors for ON.