title: The effect of treatment with a thiazide diuretic for 4 years on bone density in normal postmenopausal women.
abstract: 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.
authors.affiliation: Department of Medicine, University of Auckland, Auckland, New Zealand. osteo@auckland.ac.nz
authors.forename: M J
authors.initials: MJ
authors.lastname: Bolland
authors.forename: R W
authors.initials: RW
authors.lastname: Ames
authors.forename: A M
authors.initials: AM
authors.lastname: Horne
authors.forename: B J
authors.initials: BJ
authors.lastname: Orr-Walker
authors.forename: G D
authors.initials: GD
authors.lastname: Gamble
authors.forename: I R
authors.initials: IR
authors.lastname: Reid
mesh_terms: 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
chemical_list: D049993:Sodium Chloride Symporter Inhibitors; D006852:Hydrochlorothiazide; D002118:Calcium