[Bone density and laboratory parameters of bone metabolism in patients with terminal heart disease].

PURPOSE

The purpose of this study was to assess bone mineral density (BMD) and parameters for bone metabolism in patients with end-stage heart disease awaiting heart transplantation to determine whether these patients are at increased risk of bone disease.

PATIENTS AND METHODS

39 adult men (mean age 52.3, range 21-65 years) with ischemic (41%), idiopathic (43.5%), valvular (2.5%) and diverse (13%) end-stage heart disease were studied prior to heart transplantation. BMD was measured using dual-energy x-ray absorptiometry at the lumbar spine (L2-L4) and at the upper femur (Ward's triangle and femoral neck). Renal and bone biochemical profiles, parathyroid hormone (PTH), 25-OH-vitamin D3, testosterone, alkaline bone phosphatase, osteocalcin, and deoxypyridinoline and calcium excretion were measured.

RESULTS

No fractures were found. Mean z-scores were -1.06 +/- 2.02 (mean +/- SD) at the lumbar spine, -1.12 +/- 2.03 at the femoral neck and -0.25 +/- 1.06 at Ward's triangle. Significantly decreased values were seen at the lumbar spine and at the femoral neck compared to age matched healthy controls. Mean values of serum creatinine and parathyroid hormone were elevated (114.4 +/- 29.5 mumol/l and 84.3 +/- 67.8 ng/l, respectively). 7 (18%), 10 (26%) and 22 (56%) of the 39 patients had values beneath the normal range of 25-OH-vitamin D3, testosterone and osteocalcin respectively. Mean urinary deoxypyridinoline/creatinine ratios were elevated (9.46 +/- 8.52 nmol/mmol, normal range 2.5-5). No correlation existed between osteocalcin and urinary deoxypyridinoline/creatinine ratio. Using a multiple linear regression model, serum PTH and cardiac ejection fraction (EF) weakly predicted BMD at the femoral neck (r2 = 0.26).

CONCLUSIONS

(1.) Lumbar spine and femoral neck BMD are low in patients awaiting heart transplantation. (2.) A low EF and a high PTH weakly correlate with a decrease in BMD at the femoral neck. (3.) In patients with end-stage heart failure the coupling of bone formation to bone resorption is frequently disturbed. (4.) Testosterone and 25-OH-vitamin D3 levels are low in a number of patients and in such cases replacement therapy may be appropriate.