The effect of treatment with a thiazide diuretic for 4 years on bone density in normal postmenopausal women.
CONCLUSIONS
We performed a 2-year extension of our previous 2-year randomized controlled trial of the effects of hydrochlorothiazide on bone mineral density. The improvements in bone density seen in the first 2 years were sustained throughout the extension study. Thiazides provide a further option in the prevention of postmenopausal bone loss.


BACKGROUND
Thiazide diuretics reduce urinary calcium excretion and therefore might prevent osteoporosis. Previously we reported a 2-year randomized controlled trial of hydrochlorothiazide treatment in 185 postmenopausal women that showed positive benefits of hydrochlorothiazide on bone density. Here, we report the results of a 2-year extension to that study.


METHODS
Of 185 healthy postmenopausal women, 122 agreed to continue in a double-blinded 2-year extension taking 50 mg hydrochlorothiazide or placebo daily. Measurements of bone density occurred every 6 months and of calcium metabolism at 2 and 4 years.


RESULTS
The improvements in bone density seen in the first 2 years of the trial were sustained throughout the extension. There were significant between-groups differences in the change in bone density over 4 years at the total body (0.9%, P<0.001), legs (1.0%, P=0.002), mid-forearm (1.1%, P=0.03), and ultradistal forearm (1.4%, P=0.04). At the lumbar spine (0.9%, P=0.76) and femoral neck (0.4%, P=0.53) the between-groups differences did not reach statistical significance.


CONCLUSIONS
Hydrochlorothiazide produces small positive benefits on cortical bone density that are sustained for at least the first 4 years of treatment. They provide a further option in the prevention of postmenopausal bone loss, especially for women with hypertension or a history of kidney stones.
Bolland
M J
MJ
Department of Medicine, University of Auckland, Auckland, New Zealand. osteo@auckland.ac.nz
Ames
R W
RW
Horne
A M
AM
Orr-Walker
B J
BJ
Gamble
G D
GD
Reid
I R
IR
D001774:Blood Chemical Analysis / Q000379:methods; D015519:Bone Density / Q000187:drug effects*; D001862:Bone Resorption / Q000503:physiopathology / Q000517:prevention & control; D002118:Calcium / Q000378:metabolism; D004311:Double-Blind Method; D005260:Female; D050723:Fractures, Bone / Q000517:prevention & control; D006801:Humans; D006852:Hydrochlorothiazide / Q000009:adverse effects / Q000627:therapeutic use*; D007867:Leg Bones / Q000502:physiology; D008134:Long-Term Care / Q000379:methods; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control; D017698:Postmenopause / Q000502:physiology*; D049993:Sodium Chloride Symporter Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D013131:Spine / Q000502:physiology; D016896:Treatment Outcome
D049993:Sodium Chloride Symporter Inhibitors; D006852:Hydrochlorothiazide; D002118:Calcium