Can Alendronate Suppress Aortic and Coronary Artery Calcification and Improve Bone Mineral Density in Chronic Peritoneal Dialysis Patients?

OBJECTIVES The purpose of this study is to determine if long-term use of alendronate can suppress coronary artery and aortic calcification in chronic PD patients. The effect of alendronate on bone mineral density in this patient group is also evaluated.

METHODS

1. Patients To be eligible for the study, patients have to meet all of the following criteria: (1) have received maintenance PD for more than 3 months at Far Eastern Memorial Hospital, (2) have high CPP level (≧55), and (3) have chest X-ray proven aortic calcification or coronary artery calcification proven before. Patients are excluded if they have any one of the following conditions: (1) had been hospitalized in recent 3 months due to severe comorbid diseases, (2) are hypersensitive to alendronate or any of its components, (3) have esophageal diseases (4) are not able to stand or sit upright for 30 minutes, (5) have refractory hypocalcemia, or (6) patients who are pregnant.

Each eligible participant has to give his/her written informed consent before the start of study. The study should be approved by the Institutional Review Board of the hospital. 2. Study Design The study is a prospective, randomized cross-over study. Fifty patients will be included. All participants are randomly allocated to either group 1 or group 2. Each group consists of 25 patients. Group 1 patients receive alendronate 70 mg once weekly since the first week till the 16th week of the study, while group 2 patients receive the same dose of drug every week since the 17th week till the 32nd week. Group 1 patients will not receive alendronate since the 17th week till the 32nd week, and group 2 patients will not receive alendronate since the first week till the 16 week. The extent of coronary artery and aortic calcification is evaluated by using multi-detector spiral computed tomography, whereas bone mineral density is measured by dual-energy X-ray absorptiometry. Both examinations are performed at week 0, 16 and 32 for each participant. Serum level of calcium should be kept within normal limits and serum level of phosphorus should be kept below 6 mg/dl.

（3）Administration of Alendronate One tablet of alendronate (70 mg per tablet) should be swallowed by each patient once every week with water at least 30 minutes before breakfast, beverage or medication of the day during the treatment period. Patients must not lie down for at least 30 minutes after taking the drug.