Peter Burckhardt

Intravenous ibandronate in men with osteoporosis: An open pilot study over 2 years

In the treatment of osteoporosis, the tolerance of oral bisphosphonates is often low. The high potency of ibandronate allows iv bolus injections that can be repeated every 2 to 3 months. However, the best dose and time interval of the treatment with iv ibandronate is still debated. Efficacy of 2-mg ibandronate injected every 3 months was tested in men with osteoporosis over 2 yr, in a prospective, open study. Fourteen men with primary osteoporosis, mean age 57±12 yr (range: 40–73), received 2-mg ibandronate iv every 3 months over 2 yr. All got 1 g/day calcium and 880 UI/day vitamin D for 2 yr. Bone mineral density (BMD) increased after 2 yr by 6.7±1.5% (mean change±SEM) at lumbar spine (p<0.001), by 3.2±08% at trochanter (p<0.001) and by 1.4±1.1% at femoral neck (ns). Serum ß-crosslaps and osteocalcin decreased significantly by 30–45 and 30%, respectively, during the 2 yr of treatment. Serum calcium increased from the lower to the middle tertile of the normal range during the 2 yr of the study. The observed decrease of bone remodelling and the increase of BMD are of the same magnitude as those described with oral bisphosphonates. The increase of plasma calcium confirms the positive effect of the supplementation with calcium and vitamin D. These results suggest that 3 months are a good interval between two doses of iv ibandronate, when 2 mg are given.

Hypercalcemia of Malignancy

Hypercalcemia of malignancy (HCM) is the most common life-threatening metabolic complication of malignancy and affects 10 to 20% of patients with advanced cancer. In oncology units, its incidence varies between 0.5 and 10.9%. In more than half of the patients, it is associated with pulmonary and mammary cancers. In the presence of hypercalcemia, it is important to recognize co-existing conditions, like primary hyperparathyroidism, that could partially explain the elevation of serum calcium. HCM causes a series of symptoms which decrease quality of life. Constipation, nausea and vomiting, confusion and/or stupor, polyuria and polydipsia, as well as bone pain, are specific to HCM. The normalization of calcemia significantly improves all of these symptoms. However, HCM remains largely underdiagnosed in medical practice. Furthermore, specific treatment of HCM in the hospital is usually late, and patients are rarely given adequate rehydration.HCM should be treated as an emergency upon diagnosis. Patients with normalized calcium levels have a better quality of life and are usually able to return home. Treatments for patients with HCM include: (i) rapid rehydration with isotonic saline intravenously; (ii) intravenous bisphosphonates; and (iii) calcitonin in addition to bisphosphonates for patients whose levels of serum calcium are in the life-threatening range (≥4 mmo1/L). The most currently used bisphosphonates are clodronic acid and pamidronic acid; however, the increased convenience of a 15-minute infusion, greater efficacy (∼90%), and longer duration of response (∼30 days) should make zoledronic acid the new standard of treatment for patients with HCM. Corticosteroids are highly effective agents for the treatment of patients with hematological cancer and calcitriol-mediated hypercalcemia. Promising new treatments for patients with HCM include antibodies to parathyroid hormone-related peptide and osteoprotegrin.

Calcium revisited, part III: effect of dietary calcium on BMD and fracture risk

Food can be an excellent source of calcium. Dietary calcium is in general as well absorbed as calcium supplements, and exerts the same effects on bone. The main sources are dairy products, but also some vegetables and fruits contain considerable amounts of calcium. Mineral water can serve as a supplement. Cross-sectional, longitudinal and some interventional trials have shown positive effects on bone metabolism, bone density and bone loss. But the effect on fracture incidence is less certain, and that of milk, the most studied dairy product, still unproven.

Calcium revisited: part II calcium supplements and their effects.

Calcium supplements were tested in pregnancy and lactation, in childhood and adolescence, in pre- and postmenopausal women and in elderly persons with various effects on bone density and fracture incidence. They must be properly chosen and adequately used. In this case, the reported minor negative side-effects do not restrict their use. All these aspects are reviewed here.