Does hormone replacement therapy affect the use of prescription medicines in postmenopausal women: experience from the Estonian Postmenopausal Hormone Therapy Trial [ISRCTN35338757].
OBJECTIVE
To determine how postmenopausal hormone therapy (HRT) is related to the use of other prescription medication.


METHODS
Follow up of a randomised controlled trial with a blind subtrial of hormone therapy versus placebo and a nonblind subtrial of open label hormone therapy versus nontreatment.


METHODS
A total of 1823 postmenopausal women aged 50-64 at the time of sampling participated in the trial from 1999 to 2004.


METHODS
Use of prescription medication was identified by records in the central computerised database of the Estonian Health Insurance Fund.


METHODS
The use of 21 classes of prescription medication was compared in the hormone therapy arms and placebo or nontreatment trial arms. The influence of women's socio-economic characteristics on the intensity of concomitant medication use was also examined.


RESULTS
The proportion of women using any prescription medication besides hormone therapy did not differ between the arms. However, the type of prescribed drugs varied between the arms. After combining data from both hormone therapy arms, for women using HRT the combined hazard ratio was 1.26 (95% CI: 1.05-1.53) for the use of calcium channel blockers, 1.48 (95% CI: 1.10-1.99) for local vaginal treatment, 0.70 (95% CI: 0.50-0.99) for hypnotics and sedatives and 0.77 (95% CI: 0.60-0.99) for selective serotonin reuptake inhibitors (SSRIs). Women who were older, who had a higher body mass index, who were unemployed and who lived outside the capital used more prescription drugs in comparison with others.


CONCLUSIONS
Hormone therapy did not increase the overall use of prescription medication other than hormone therapy, but the types of drugs used in hormone therapy and nontherapy arms varied, with increased use of calcium channel blockers for hypertension and local vaginal treatments for vaginal candidiasis and decreased use of hypnotics, sedatives and SSRIs in the HRT arms.
Veerus
P
P
Department of Epidemiology and Biostatistics, National Institute for Health Development (TAI), Tallinn, Estonia. piret.veerus@tai.ee
Fischer
K
K
Hovi
S-L
SL
Karro
H
H
Hemminki
E
E
D004311:Double-Blind Method; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D004358:Drug Therapy; D005260:Female; D020249:Hormone Replacement Therapy / Q000706:statistics & numerical data*; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause / Q000187:drug effects*; D011379:Prognosis