Resistance exercise training and alendronate reverse glucocorticoid-induced osteoporosis in heart transplant recipients.
BACKGROUND
Immunosuppression therapy with bolus glucocorticoids causes regional osteoporosis in the axial skeleton of heart transplant recipients (HTR). No preventive strategy is generally accepted for steroid-induced bone loss.


METHODS
To determine the efficacy of an anti-osteoporosis regimen that combined a bisphosphonate agent (alendronate sodium) with the osteogenic stimulus of mechanical loading, 25 HTRs were randomly assigned either to a group that received alendronate (10 mg/day) for 6 months (ALEN; n = 8), a group that received alendronate (10 mg/day) and performed specific resistance exercises for 6 months (ALEN + TRN; n = 8) or to a non-intervention control group (CONTR; n = 9). Alendronate was initiated at 2 months after transplantation. Bone mineral density (BMD) of the total body, femur neck and lumbar spine (L-2 and L-3) was measured by dual-energy X-ray absorptiometry before and 2, 5 and 8 months after transplantation. Resistance training consisted of lumbar extension exercise (MedX) performed 1 day/week and 8 variable resistance exercises (MedX) performed 2 days/week.


RESULTS
Pre-transplantation BMD values did not differ among the 3 groups. BMD of the total body, femur neck and lumbar vertebra were significantly decreased below baseline at 2 months after transplantation in CONTR (-2.6 +/- 0.9%, -5.1 +/- 1.8%, -12.5 +/- 4.2%, respectively), ALEN (-2.8 +/- 0.8%, -5.3 +/- 1.6%, -12.0 +/- 3.9%) and ALEN + TRN groups (-2.7 +/- 1.0%, -5.6 +/- 2.1%, -11.2 +/- 3.7%). CONTR had further significant losses of BMD after 3 and 6 months. ALEN had no further regional BMD losses after initiation of alendronate therapy. ALEN + TRN restored BMD of the whole body, femur neck and lumbar vertebra to within 0.9%, 2.1%, and 3.4% of pre-transplantation levels, respectively.


CONCLUSIONS
Resistance exercise plus alendronate was more efficacious than alendronate alone in restoring BMD in HTRs. Our results indicate that anti-osteoporosis therapy in this population should include both an anti-resorptive agent as well as an osteogenic stimulus, such as mechanical loading.
Braith
Randy W
RW
Center for Exercise Science, College of Health and Human Performance, University of Florida, PO Box 118206, Gainesville, FL 32611, USA. rbraith@hhp.ufl.edu
Magyari
Peter M
PM
Fulton
Michael N
MN
Aranda
Juan
J
Walker
Tracy
T
Hill
James A
JA
D019386:Alendronate / Q000627:therapeutic use*; D015519:Bone Density; D005081:Exercise Therapy; D005260:Female; D005938:Glucocorticoids / Q000009:adverse effects* / Q000627:therapeutic use; D006084:Graft Rejection / Q000453:epidemiology; D016027:Heart Transplantation / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000139:chemically induced* / Q000517:prevention & control*; D011183:Postoperative Complications / Q000139:chemically induced* / Q000517:prevention & control*; D013997:Time Factors
D005938:Glucocorticoids; D007166:Immunosuppressive Agents; D019386:Alendronate