Effects of alendronate on bone turnover markers in early postmenopausal women

Alendronate sodium (Fosamax, Merck, Sharp & Dohme, Whitehouse Station, NJ, USA) is an aminobisphosphonate that can inhibit osteoclast-mediated bone resorption activity to reduce bone turnover rate and improve progressive gains in bone mass.

This was a randomized, double-blind, placebo-controlled study comparing the effects on bone turnover markers between daily treatment with alendronate sodium 10 mg and placebo. Forty early postmenopausal women completed three months of treatment. The bone turnover rate was determined by measuring the biochemical markers at baseline, week 6 and at the end of the three-month treatment period. All adverse events were recorded during each follow-up visit.

Patients receiving alendronate treatment had a significant decrease in urinary excretion of the bone resorption marker deoxypyridinoline (Dpd) as well as one of the bone formation markers, bone-specific alkaline phosphatase (AlkP-B). Patients receiving placebo tended to have increased urinary excretion of bone resorption and formation markers. At the end of three months, the mean percentage change of Dpd and AlkP-B from baseline in the group receiving 10 mg alendronate was 30.49% and 29.45% reduction, respectively. The placebo group had 2.39% and 1.52% increase, respectively. Overall, three biochemical markers (Dpd, AlkP-B and osteocalcin) differed significantly between the treatment and control groups after three months of treatment. The drug was well tolerated, without a significant increase in incidence of adverse effects such as gastrointestinal discomfort and esophageal irritation.

Bone turnover rate decreased quickly following drug administration. The incidence of adverse effects did not differ significantly between the alendronate and placebo groups. Alendronate is, therefore, recommended as an effective nonhormonal treatment for postmenopausal osteoporosis.