Prevention of bone loss with alendronate in postmenopausal women under 60 years of age. Early Postmenopausal Intervention Cohort Study Group.
BACKGROUND
Estrogen-replacement therapy prevents osteoporosis in postmenopausal women by inhibiting bone resorption, but the balance between its long-term risks and benefits remains unclear. Whether other antiresorptive therapies can prevent osteoporosis in these women is also not clear.


METHODS
We studied the effect of 2.5 mg or 5 mg of alendronate per day or placebo on bone mineral density in 1174 postmenopausal women under 60 years of age. An additional 435 women who were prepared to receive a combination of estrogen and progestin were randomly assigned to one of the above treatments or open-label estrogen-progestin. The main outcome measure was the change in bone mineral density of the lumbar spine, hip, distal forearm, and total body measured annually for two years by dual-energy x-ray absorptiometry.


RESULTS
The women who received placebo lost bone mineral density at all measured sites, whereas the women treated with 5 mg of alendronate daily had a mean (+/-SE) increase in bone mineral density of 3.5+/-0.2 percent at the lumbar spine, 1.9+/-0.1 percent at the hip, and 0.7+/-0.1 percent for the total body (all P<0.001). Women treated with 2.5 mg of alendronate daily had smaller increases in bone mineral density. Alendronate did not increase bone mineral density of the forearm, but it slowed the loss. The responses to estrogen-progestin were 1 to 2 percentage points greater than those to the 5-mg dose of alendronate. Alendronate was well tolerated, with a safety profile similar to that of placebo or estrogen-progestin.


CONCLUSIONS
Alendronate prevents bone loss in postmenopausal women under 60 years of age to nearly the same extent as estrogen-progestin.
Hosking
D
D
Division of Mineral Metabolism, City Hospital, Nottingham, United Kingdom.
Chilvers
C E
CE
Christiansen
C
C
Ravn
P
P
Wasnich
R
R
Ross
P
P
McClung
M
M
Balske
A
A
Thompson
D
D
Daley
M
M
Yates
A J
AJ
D019386:Alendronate / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use*; D015519:Bone Density / Q000187:drug effects*; D004311:Double-Blind Method; D004338:Drug Combinations; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D005542:Forearm; D006801:Humans; D008159:Lumbar Vertebrae / Q000187:drug effects; D008525:Medroxyprogesterone / Q000494:pharmacology / Q000627:therapeutic use*; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control*; D010384:Pelvic Bones / Q000187:drug effects; D017698:Postmenopause; D045167:Progesterone Congeners / Q000494:pharmacology / Q000627:therapeutic use
D004338:Drug Combinations; D004966:Estrogens, Conjugated (USP); D045167:Progesterone Congeners; D008525:Medroxyprogesterone; D019386:Alendronate