Cor Vasa 2004, 45(1):20-23
Bone changes after heart transplantation
- 1 Ústav preventívnej a klinickej medicíny
- 2 Slovenský ústav srdcových a cievnych chorôb, Bratislava, Slovenská republika
Aim of study:
To determine the status of bone mass, biochemical parameters of mineral metabolism and markers of bone remodeling in heart transplant recipients.
Group of patients and method:
The group included 45 heart transplant recipients. We investigated the main biochemical markers of mineral metabolism in the serum (Ca, Mg, Pi, total ALP) and urine (Ca, Mg, Pi and their fractional excretion rates) of patients. Renal function was determined using creatinine clearance. The levels of intact parathyroid hormone (iPTH) were determined by IRMA; those of osteocalcin using ELISA and urinary N-telopeptide (NTx) by EIA. 25-OH vitamin D3 (calcidiol) levels were determined in serum by means of RIA. Bone mineral density (BMD) was measured using dual energy x-ray absorptiometry (DEXA) with a Lunar-DPXL device in the femoral neck and lumbar spine (L1-L4) regions. Statistical analysis was made using Statgraphics Version 5 software, with data evaluated by the t-test, Wilcoxon's test and ANOVA.
Results:
The levels of Ca, Mg, and Pi were within normal, Ca excretion/24 hours was decreased (2.06 ± 0.20 mmol/d). Total ALP activity was at the upper limit of normal (2,04 ± 0,19 µkat/L). The average urinary levels of iPTH (116.7 ± 10.1 pg/mL), osteocalcin (55.84 ± 5.19 ng/mL) and NTx (80.88 ± 14.51 nmol/mmol creatinine) were elevated. Patients showed moderate vitamin D deficiency (18.6 ± 2.2 ng/mL).
Densitometry documented osteopenia in 46% of patients, osteoporosis in 27% while normal BMD was present in 27% of patients. No correlation was demonstrated between the post-transplant period and severity of bone changes or cumulative prednisone dose.
Conclusion:
We have demonstrated that bone changes (osteopenia and/or osteoporosis) are present in more than 2/3 of heart transplant recipients. Factors contributing to the development of these changes in the pre-transplant period include physical inactivity, malnutrition, effect of therapy (heparin, loop diuretics, corticosteroids), hypogonadism, hepatic stasis, reduced renal function, and others, with immunosuppressive therapy after transplantation as an additional factor. It is therefore critical to provide heart transplant recipients but, most importantly, those scheduled for transplantation, with adequate prevention and management of these changes.
Keywords: Heart transplantation; Bone density; Intact parathyroid hormone; Vitamin D; Corticosteroids
Published: January 1, 2004 Show citation