Alendronate in Primary Hyperparathyroidism: A Double- Blind, Randomized, Placebo-Controlled Trial

Primary hyperparathyroidism (PHPT) is often associated with reduced bone mineral density (BMD). A randomized, double-blind, placebo-controlled trial was conducted to de-termine whether alendronate (ALN), 10 mg daily, maintains or improves BMD in patients with PHPT. Eligible patients had asymptomatic PHPT and did not meet surgical guidelines or refused surgery. Forty-four patients randomized to placebo or active treatment arms were stratified for gender. At 12 months, patients taking placebo crossed over to active treat-ment. All patients were on active treatment in yr 2. The pri-mary outcome index, BMD, at the lumbar spine (LS), femoral neck, total hip, and distal one third radius was measured every 6 months by dual-energy x-ray absorptiometry. Cal-cium, phosphorous, PTH, bone-specific alkaline phosphatase (BSAP) activity, urinary calcium, and urinary N-telopeptid