TY - JOUR

T1 - Risk of Stroke with Various Types of Menopausal Hormone Therapies

T2 - A National Cohort Study

AU - Løkkegaard, Ellen

AU - Nielsen, Lars Hougaard

AU - Keiding, Niels

PY - 2017

Y1 - 2017

N2 - Background and Purpose: Double-blind randomized studies on the effects of oral postmenopausal hormone therapies were stopped mainly because of increased risk of stroke. We aimed to assess the risk of all strokes and various subtypes associated with hormone therapy and explore the influence of regimens and routes of administration. Methods: A national historical cohort of women aged 51 to 70 years from 1995 to 2010 was established by linking 5 Danish registries. The National Registry of Medicinal Product Statistics provided information on hormone therapy exposure and the National Patient or Cause of Death Registries supplied data regarding stroke diagnoses (ischemic/hemorrhagic/subarachnoid hemorrhage). Multiply adjusted rate ratios with time-varying covariates were fitted in Poisson regression models. Results: Of the 980 003 included women, 20 199 suffered a stroke (78% ischemic, 12% hemorrhagic, and 10% subarachnoid hemorrhage). In total, 36% of women used hormone therapy. Current use conferred a relative rate of 1.16 (95% confidence interval, 1.12-1.22). Compared with never users, the increased rate ratio of all stroke with continuous, cyclic combined estrogen/progestin, and estrogen only oral therapies were 1.29 (95% confidence interval, 1.21-1.37), 1.11 (95% confidence interval, 1.04-1.20), and 1.18 (95% confidence interval, 1.10-1.26), respectively. The increased risk was because of ischemic stroke, but not hemorrhagic stroke. Transdermal application of hormone therapy was not associated with risk of stroke. Vaginal estrogen was associated with a decreased risk of stroke. Conclusions: In a national setting, we found an increased risk of stroke, based on ischemic stroke, with oral hormone therapies that was comparable to findings from randomized studies. We found no risk of stroke with transdermal application and a reduced risk with vaginal estrogen.

AB - Background and Purpose: Double-blind randomized studies on the effects of oral postmenopausal hormone therapies were stopped mainly because of increased risk of stroke. We aimed to assess the risk of all strokes and various subtypes associated with hormone therapy and explore the influence of regimens and routes of administration. Methods: A national historical cohort of women aged 51 to 70 years from 1995 to 2010 was established by linking 5 Danish registries. The National Registry of Medicinal Product Statistics provided information on hormone therapy exposure and the National Patient or Cause of Death Registries supplied data regarding stroke diagnoses (ischemic/hemorrhagic/subarachnoid hemorrhage). Multiply adjusted rate ratios with time-varying covariates were fitted in Poisson regression models. Results: Of the 980 003 included women, 20 199 suffered a stroke (78% ischemic, 12% hemorrhagic, and 10% subarachnoid hemorrhage). In total, 36% of women used hormone therapy. Current use conferred a relative rate of 1.16 (95% confidence interval, 1.12-1.22). Compared with never users, the increased rate ratio of all stroke with continuous, cyclic combined estrogen/progestin, and estrogen only oral therapies were 1.29 (95% confidence interval, 1.21-1.37), 1.11 (95% confidence interval, 1.04-1.20), and 1.18 (95% confidence interval, 1.10-1.26), respectively. The increased risk was because of ischemic stroke, but not hemorrhagic stroke. Transdermal application of hormone therapy was not associated with risk of stroke. Vaginal estrogen was associated with a decreased risk of stroke. Conclusions: In a national setting, we found an increased risk of stroke, based on ischemic stroke, with oral hormone therapies that was comparable to findings from randomized studies. We found no risk of stroke with transdermal application and a reduced risk with vaginal estrogen.

KW - estrogen

KW - hormonal therapy

KW - ischemic stroke

KW - menopause

KW - stroke

UR - https://doi.org/10.1161/STR.0000000000000167

U2 - 10.1161/STROKEAHA.117.017132

DO - 10.1161/STROKEAHA.117.017132

M3 - Journal article

C2 - 28626058

AN - SCOPUS:85021127244

VL - 48

SP - 2266

EP - 2269

JO - Stroke

JF - Stroke

SN - 0039-2499

IS - 8

ER -